FIELD OF THE INVENTION 0001 The present invention relates to a positive-working photosensitive composition that is used in the production step of semiconductors such as IC, the production of circuit boards of liquid crystals, thermal heads, etc., and other photo-fabrication steps.

BACKGROUND OF THE INVENTION 0002 A positive-working photoresist is applied in a thickness of from 0.5 to 2 m on a substrate such as semiconductor wafers, glass, ceramics, and metals by spin coating or roller coating. Thereafter, the photoresist is heated, dried, and printed with a circuit pattern or the like through an exposure mask upon irradiation with ultraviolet rays or the like. After the exposure, the photoresist is baked, if desired and then developed to form a positive image. Further, by etching using this positive image as a mask, a pattern-like processing can be carried out on the substrate. Examples of representative application fields include the production step of semiconductors such as IC, the production of circuit boards of liquid crystals, thermal heads, etc., and other photo-fabrication steps. 0003 Hitherto, in order to enhance a resolving power and obtain image reproduction with a good pattern shape, it is considered that the use of a resist having high contrast ( value) is advantageous, and technologies for the development of resist compositions adapted to such purpose have been carried out. An extremely large number of publications disclose such technologies. Especially, with respect to resins as a major component of positive-working photoresists, many patents have been applied regarding the monomer compositions, molecular weight distributions, synthesis methods, etc., thereby realizing certain results. Further, with respect to photosensitive materials as another major component, compounds having a varied structure, which are seemed to be effective for revealing high contrast, are disclosed. When a positive-working photoresist is designed utilizing these technologies, it may be possible to develop resists having a super-high resolving power, which can resolve a pattern having a dimension equal to the wavelength of light. 0004 However, in integrated circuits, the degree of integration increases more and more. In the production of semiconductor substrates of ULSI, etc., it has become necessary to undergo processing of hyperfine patterns having a line width of 0.5 m or less. 0005 On the other hand, there have been made various attempts to further increase the resolving power by a super resolution technology such as exposure technology and mask technology. In the super resolution technology, various resolution technologies are studied on light sources, masks, pupils, and images. As to the light sources, there is a technology for increasing the resolving power by using a light source having a shape different from the conventional circle, called modified illumination. As the masks, there is reported a technology for controlling even a phase shift using a phase shift mask, i.e., giving a phase shift to light transmitting through the mask and utilizing well its interference to obtain a high resolving power (for example, Tokuhisa Ito, Optics of Steppers (1) to (4): Optical Technology Contact, Vol. 27, No. 12, 762 (1988), Vol. 28, No. 1, 59 (1990), Vol. 28, No. 2, 108 (1990) and Vol. 28, No. 3, 165 (1990), JP-A-58-173744, JP-A-62-50811, JP-A-62-67514, JP-A-1-147458, JP-A-1-283925, and JP-A-2-211451 (The term JP-A as used herein means an unexamined published Japanese Patent application)). 0006 Further, as disclosed in JP-A-8-15851, a resist exposure mode using a halftone mode phase shift mask is particularly watched as a practical technology for improving a space image and contrast of a projected image. However, in a light intensity distribution of the exposing light reaching the resist, not only a main peak but also a so-called sub-peak (side lobe light) are generated, and areas of the resist that should not be originally exposed are exposed. Especially, the higher the degree of coherence (), the larger the sub-peak is. When the sub-peak is thus generated, in the positive-working resists, irregularities caused by the sub-peak are formed in the exposed and developed resist, and hence, such is not preferred. 0007 In the light of the above, in the projection optical system of optical lithography, various devices for attenuation are made, and combinations with various super resolution technologies are eagerly studied (for example, Halftone Type Phase Shift Mask and Annular Illumination: C. N. Ahn, et al., SPIE, Vol. 2440, 222 (1995), and T. Ogawa, et al., SPIE, Vol. 2726, 34 (1996)). 0008 However, in the case where the super resolution technology is applied, in the conventional positive-working photoresists, there has already been reported the case where the resolving power is deteriorated, the exposure margin or exposure latitude is insufficient, or irregularities (film thickness reduction) are generated, whereby the resist performance is rather deteriorated. For example, C. L. Lin, et al. report that when the modified illumination is used, the pattern pitch dependency is deteriorated by the influence of the optical proximity effect (SPIE, Vol. 2726, 437 (1996)); and N. Samarakone, et al. and I. B. Hur, et al. point out a problem that when a contact hole pattern is formed using a halftone type phase shift mask, the surroundings of the hole pattern become irregular by the influence of a side lobe light (SPIE, Vol. 2440, 61 (1995) and SPIE, Vol. 2440, 278 (1995)). In order to reduce the influence of the side lobe light, there is made a device for surface-processing the exposed positive-working resist with an alkali (T. Yasuzato, et al., SPIE, Vol. 2440, 804 (1995)). However, there is still a problem that the process is complicated. 0009 JP-A-11-109632 discloses that a resin containing a polar group-containing alicyclic functional group and an acid-decomposable group is used as a radiation-sensitive material. 0010 Further, JP-A-9-73173, JP-A-9-90637, and JP-A-10-161313 disclose resist materials using an acid-sensitive compound containing an alkali-soluble group protected by an alicyclic group-containing structure and a structural unit in which the alkali-soluble group is released by an acid to make it alkali-soluble. 0011 JP-A-10-130340 discloses a chemically amplified resist containing a terpolymer having a specific repeating structural unit having a norbornene structure in the main chain thereof. 0012 Japanese Patent No. 3,042,618 discloses a photoresist composition containing a polymer obtained by copolymerizing a lactone structure-containing (meth)acrylate derivative with other polymerizable compound. 0013 JP-A-2001-81139 proposes an improvement in resistance to dry etching by the use of a resin containing a repeating unit having a specific oxygen-containing alicyclic structure such as a lactone skeleton in the main chain thereof. 0014 JP-A-11-305444 discloses a resin containing a repeating structural unit having an adamantane structure in the side chains thereof and maleic anhydride as a repeating structural unit. 0015 JP-A-2001-13688 proposes a composition a repeating unit having a norbornene structure in the main chain thereof, a repeating unit having a maleic anhydride structure, and a repeating unit having a hydroxyl group in the side chains thereof for the purpose of providing radiation-sensitive resin compositions having superior transparency, resistance to dry etching, sensitivity, resolution, pattern shape, and preservability. JP-A-2001-209181 proposes a composition containing a resin containing a repeating unit having a norbornene structure in the main chain thereof and a repeating unit having a maleic anhydride structure. 0016 JP-A-2001-200016 discloses a composition containing a copolymer of an alkyl vinyl ether monomer and maleic anhydride for the purpose of improving the adhesion to a lower film and resistance to dry etching. 0017 JP-A-11-38628 discloses a composition containing a copolymer of a vinyl ether and a maleic ester for the purpose of improving the sensitivity, pattern profile, and adhesiveness to substrate. 0018 However, even by using these conventional resist materials, it was difficult to realize the performance satisfactorily with respect to edge roughness and development defect. 0019 Further, even by using these conventional resist materials, the resistance to side lobe light was not satisfactory during the formation a contact hole pattern using a halftone mode phase shift mask, and there was a problem in the pitch dependency (i.e., defocus latitude depended on line pitch). The pitch dependency as referred to herein means that the resolution properties are different between non-dense areas and dense areas.

SUMMARY OF THE INVENTION 0020 Accordingly, an object of the present invention is to solve the problems in performance-enhancing technologies of micro photo-fabrication using far ultraviolet rays, especially ArF excimer laser beams and to provide a positive-working photosensitive composition improved in edge roughness and development defect. 0021 Another object of the present invention is to solve the problems in performance-enhancing technologies of micro photo-fabrication using far ultraviolet rays, especially ArF excimer laser beams and to provide a positive-working photosensitive composition having low pitch dependency and superior and broad side lobe margin. 0022 A further object the present invention is to solve the problems in performance-enhancing technologies of micro photo-fabrication using far ultraviolet rays, especially ArF excimer laser beams and to provide a positive-working photosensitive composition having superior halftone phase shift mask aptitude (resistance to side lobe light) and improved in development defect and a positive-working photosensitive composition not only having the foregoing performance but also preventing pattern collapse and forming a good profile. 0023 The foregoing objects of the present invention are achieved by positive-working photosensitive compositions having the following configurations. 0024 (1) A positive-working photosensitive composition comprising: 0025 (A) at least one compound of: 0026 a compound to generate an acid upon irradiation with actinic rays or radiations, which is selected from a compound represented by the following general formula (A2I) and a compound represented by the following general formula (A2 II), 0027 a compound to generate an aromatic sulfonic acid substituted with at least one fluorine atom and/or a group having at least one fluorine atom, upon irradiation with actinic rays or radiations, and 0028 a compound to generate an acid upon irradiation with actinic rays or radiations, which is represented by the following general formula (SI); and 0029 (B) a resin having a repeating unit represented by the following general formula (I) and a repeating unit represented by the following general formula (II), which is decomposed by the action of an acid to increase its solubility in an alkaline developing solution. 1

0030 In the general formula (A2I), R1c to R5c each independently represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom; R6c and R7c each independently represents a hydrogen atom, an alkyl group, or an aryl group; Rx and Ry each independently represents an alkyl group, a 2-oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group, or a vinyl group; and any two or more of R1c to R7c, and Rx and Ry may be taken together to form a ring structure, and the ring structure may contain an oxygen atom, a sulfur atom, an ester bond, or an amide group. 0031 In the general formula (A2II), R1b to R3b each independently represents an alkyl group, and the alkyl group may be a 2-oxoalkyl group having >CO at the 2-position thereof; and two of R1b to R3b may be taken together (i.e., may be bonded) to form a ring structure. 0032 In the general formulae (A2I) and (A2II), X represents an anion. 2

0033 In the general formula (SI), Rs4 to Rs6 each independently represents an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an acyl group, an acyloxy group, a nitro group, a halogen atom, a hydroxyl group, or a carboxyl group; 1 represents from 1 to 5, m represents from 0 to 5, n represents from 0 to 5, and when (1mn)1, then R34 represents an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an acyl group, or an acyloxy group; Xs represents RSO3; and R represents an aliphatic hydrocarbon group or an aromatic hydrocarbon group. 3

0034 In the general formula (I), R1a represents a hydrogen atom or an optionally substituted hydrocarbon group; R2a represents an optionally substituted hydrocarbon group; and R1a and R2a may be taken together to form a ring. 0035 In the general formula (II), Z represents O or N(R3a); R3a represents a hydrogen atom, a hydroxyl group, an alkyl group, a haloalkyl group, or OSO2R4a; and R4a represents an alkyl group, a haloalkyl group, a cycloalkyl group, or a camphor residue. 0036 (2) The positive-working photosensitive composition as set forth in (1) as above, further comprising (C) a mixed solvent containing at least one member selected from a solvent group A: propylene glycol monoalkyl ether alkoxylates and at least one member selected from a solvent group B: propylene glycol monoalkyl ethers, alkyl lactates, and alkyl alkoxypropionates, or a mixed solvent containing at least one member selected from the solvent group A and at least one member selected from a solvent group C: -butyrolactone, ethylene carbonate, and propylene carbonate. 0037 (3) A positive-working photosensitive composition comprising (A) at least one compound to generate an acid upon irradiation with actinic rays or radiations, which is selected from a compound represented by the following general formula (A2I) and a compound represented by the following general formula (A2II); and (B) a resin having a repeating unit represented by the following general formula (I) and a repeating unit represented by the following general formula (II), which is decomposed by the action of an acid to increase its solubility in an alkaline developing solution. 4

0038 In the general formula (A2I), R1c to R5c each independently represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom; R6c and R7c each independently represents a hydrogen atom, an alkyl group, or an aryl group; Rx and Ry each independently represents an alkyl group, a 2-oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group, or a vinyl group; and any two or more of R1c to R7c and Rx and Ry may be taken together to form a ring structure, and the ring structure may contain an oxygen atom, a sulfur atom, an ester bond, or an amide group. 0039 In the general formula (A2II), R1b to R3b each independently represents an alkyl group, and the alkyl group may be a 2-oxoalkyl group having >CO at the 2-position thereof; and two of R1b to R3b may be taken together to form a ring structure. 0040 In the general formulae (A2I) and (A2II), X represents an anion. 5

0041 In the general formula (I), R1a represents a hydrogen atom or an optionally substituted hydrocarbon group; R2a represents an optionally substituted hydrocarbon group; and R1a and R2a may be taken together to form a ring. 0042 In the general formula (II), Z represents O or N(R3a); R3a represents a hydrogen atom, a hydroxyl group, an alkyl group, a haloalkyl group, or OSO2R4a; and R4a represents an alkyl group, a haloalkyl group, a cycloalkyl group, or a camphor residue. 0043 In addition, the following configurations can be enumerated as preferred embodiments. 0044 (4) The positive-working photosensitive composition as set forth in (1) as above, wherein the acid-decomposable resin contains a repeating unit having a group that is decomposed by the action of an acid, represented by any one of the following general formulae (pI) to (pV). 6

0045 In the foregoing formulae, R11 represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a sec-butyl group; Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with the carbon atoms; R12 to R16 each independently represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R12 to R14, and any one of R15 and R16 each represents an alicyclic hydrocarbon group; R17 to R21 each independently represents a hydrogen atom or a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R17 to R21 represents an alicyclic hydrocarbon atom and that any one of R19 and R21 represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms; R22 to R25 each independently represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R22 to R25 represents an alicyclic hydrocarbon atom and that R23 and R24 may be taken together to form a ring. 0046 (5) The positive-working photosensitive composition as set forth in (3) or (4) as above, wherein the resin (B) further contains a repeating unit having a lactone residue or an alicyclic lactone reside. 0047 (6) A positive-working photosensitive composition comprising (A) a compound to generate an aromatic sulfonic acid substituted with at least one fluorine atom and/or a group having at least one fluorine atom, upon irradiation with actinic rays or radiations; and (B) a resin (acid-decomposable resin) having a repeating unit represented by the following general formula (I) and a repeating unit represented by the following general formula (II), which is decomposed by the action of an acid to increase its solubility in an alkaline developing solution. 7

0048 In the general formula (I), R1a represents a hydrogen atom or an optionally substituted hydrocarbon group; R2a represents an optionally substituted hydrocarbon group; and R1a and R2a may be taken together to form a ring. 0049 In the general formula (II), Z represents O or N(R3a); R3a represents a hydrogen atom, a hydroxyl group, an alkyl group, a haloalkyl group, or OSO2R4a; and R4a represents an alkyl group, a haloalkyl group, a cycloalkyl group, or a camphor residue. 0050 In addition, the following configurations can be enumerated as preferred embodiments. 0051 (7) The positive-working photosensitive composition as set forth in (6) as above, wherein the acid-decomposable resin contains a repeating unit having a group that is decomposed by the action of an acid, represented by any one of the following general formulae (pI) to (pV). 8

0052 In the foregoing formulae, R11 represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a sec-butyl group; Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with the carbon atoms; R12 to R16 each independently represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R12 to R14, and any one of R15 and R16 each represents an alicyclic hydrocarbon group; R17 to R21 each independently represents a hydrogen atom or a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R17 to R21 represents an alicyclic hydrocarbon group and that any one of R19 and R21 represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms; R22 to R25 each independently represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R22 to R25 represents an alicyclic hydrocarbon atom and that R23 and R24 may be taken together to form a ring. 0053 (8) The positive-working photosensitive composition as set forth in (6) or (7) as above, wherein the resin (B) further contains a repeating unit having a lactone residue or an alicyclic lactone reside. 0054 (9) The positive-working photosensitive composition as set forth in any one of (6) to (8) as above, wherein the compound (A) is a compound represented by any one of the following general formulae (A1I) to (A1III). 9

0055 In the foregoing formulae, R1 to R37, which may be the same or different, each independently represents a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a hydroxyl group, a halogen atom, or an SR38 group; R38 represents a linear, branched or cyclic alkyl group or an aryl group; two or more of R1 to R15, R16 to R27, or R28 to R37 may be taken together to form a ring containing one or two or more members selected from a simple bond, carbon, oxygen, sulfur, and nitrogen; and X represents an anion of an aromatic sulfonic acid such as benzenesulfonic acid, naphthalenesulfonic acid, and anthracenesulfonic acid, having at least one member selected from at least one fluorine atom, a linear, branched or cyclic alkyl group substituted with at least one fluorine atom, a linear, branched or cyclic alkoxy group substituted with at least one fluorine atom, an acyl group substituted with at least one fluorine atom, an acyloxy group substituted with at least one fluorine atom, an alkyl- or arylsulfonyl group containing at least one fluorine atom, an alkyl- or arylsulfonyloxy group containing at least one fluorine atom, an alkyl- or arylsulfonylamino group containing at least one fluorine atom, an aryl group substituted with at least one fluorine atom, an aralkyl group substituted with at least one fluorine atom, and an alkoxycarbonyl group substituted with at least one fluorine atom. 0056 (10) A positive-working photosensitive composition comprising (A) a compound to generate an acid upon irradiation with actinic rays or radiations, which is represented by the following general formula (SI); (B) a resin having a repeating unit represented by the following general formula (I) and a repeating unit represented by the following general formula (II), which is decomposed by the action of an acid to increase its solubility in an alkaline developing solution; and (C) a mixed solvent containing at least one member selected from a solvent group A: propylene glycol monoalkyl ether alkoxylates and at least one member selected from a solvent group B: propylene glycol monoalkyl ethers, alkyl lactates, and alkyl alkoxypropionates, or a mixed solvent containing at least one member selected from the solvent group A and at least one member selected from a solvent group C: -butyrolactone, ethylene carbonate, and propylene carbonate. 10

0057 In the general formula (SI), Rs4 to Rs6 each independently represents an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an acyl group, an acyloxy group, a nitro group, a halogen atom, a hydroxyl group, or a carboxyl group; 1 represents from 1 to 5, m represents from 0 to 5, n represents from 0 to 5, and when (1mn)1, then Rs4 represents an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an acyl group, or an acyloxy group; Xs represents RSO3; and R represents an aliphatic hydrocarbon group or an aromatic hydrocarbon group. 0058 In the general formula (I), R1a represents a hydrogen atom or an optionally substituted hydrocarbon group; R2a represents an optionally substituted hydrocarbon group; and R1a and R2a may be taken together to form a ring. 0059 In the general formula (II), Z represents O or N(R3a); R3a represents a hydrogen atom, a hydroxyl group, an alkyl group, a haloalkyl group, or OSO2R4a; and R4a represents an alkyl group, a haloalkyl group, a cycloalkyl group, or a camphor residue. 0060 (11) The positive-working photosensitive composition as set forth in (10) as above, further comprising (F) a fluorine-based surfactant and/or a silicon-based surfactant. 0061 According to this embodiment set forth in (11) as above, the formation of a good profile is more ensured without causing pattern collapse. 0062 In addition, the following configurations can be enumerated as preferred embodiments. 0063 (12) The positive-working photosensitive composition as set forth in (10) or (11) as above, wherein the acid-decomposable resin contains a repeating unit having a group that is decomposed by the action of an acid, represented by any one of the following general formulae (pI) to (pV). 11

0064 In the foregoing formulae, R11 represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a sec-butyl group; Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with the carbon atoms; R12 to R16 each independently represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R12 to R14, and any one of R15 and R16 each represents an alicyclic hydrocarbon group; R17 to R21 each independently represents a hydrogen atom or a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R17 to R21 represents an alicyclic hydrocarbon atom and that any one of R19 and R21 represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms; R22 to R25 each independently represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R22 to R25 represents an alicyclic hydrocarbon atom and that R23 and R24 may be taken together to form a ring. 0065 (13) The positive-working photosensitive composition as set forth in any one of (10) to (12) as above, wherein the resin (B) further contains a repeating unit having a lactone residue or an alicyclic lactone reside. 0066 (14) The positive-working photosensitive composition as set forth in any one of (10) to (13) as above, wherein the mixed solvent (C) is a mixed solvent containing at least one member selected from the solvent group A, at least one member selected from the solvent group B, and at least one member selected from the solvent group C.

DETAILED DESCRIPTION OF THE INVENTION 0067 1 (A) Compound to Generate an Acid Upon Irradiation with Actinic Rays or Radiations: 0068 In the present invention, as the compound (A) to generate an acid upon irradiation with actinic rays or radiations (photo acid generator) is used at least one member selected from a compound having a phenacylsulfonium salt structure and a compound having a sulfonium salt structure not having an aromatic ring, each of which compounds generates an acid upon irradiation with actinic rays or radiations. 0069 As the compound having a phenacylsulfonium salt structure, which generates an acid upon irradiation with actinic rays or radiations, can be enumerated a compound represented by the following general formula (A2I). 12

0070 In the general formula (A2I), R1c to R5c each independently represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom; R6c and R7c each independently represents a hydrogen atom, an alkyl group, or an aryl group; Rx and Ry each independently represents an alkyl group, a 2-oxoalkyl group, an alkoxycarbonylmethyl group, an allyl group, or a vinyl group; any two or more of R1c to R7c, and Rx and Ry may be taken together to form a ring structure, and the ring structure may contain an oxygen atom, a sulfur atom, an ester bond, or an amide group; and X represents an anion (such as a sulfonic anion, carboxylic anion, and a sulfonylimide anion). 0071 The alkyl group represented by R1c to R5c may be linear, branched or cyclic. Examples include an alkyl group having from 1 to 10 carbon atoms, and preferably a linear or branched alkyl group having from 1 to 5 carbon atoms (such as a methyl group, an ethyl group, a linear or branched propyl group, a linear or branched butyl group, and a linear or branched pentyl group,) or a cyclic alkyl group having from 3 to 8 carbon atoms (such as a cyclopentyl group and a cyclohexyl group). 0072 The alkoxy group represented by R1c to R5c may be linear, branched or cyclic. Examples include an alkoxy group having from 1 to 10 carbon atoms, and preferably a linear or branched alkyl group having from 1 to 5 carbon atoms (such as a methox group, an ethoxy group, a linear or branched propoxy group, a linear or branched butoxy group, and a linear or branched pentoxy group,) or a cyclic alkoxy group having from 3 to 8 carbon atoms (such as a cyclopentyloxy group and a cyclohexyloxy group). 0073 Preferably, any one of R1c to R5c represents a linear, branched or cyclic alkyl group or a linear, branched or cyclic alkoxy group, and more preferably, the total sum of carbon atoms of R1c to R5c is from 2 to 15. Thus, the solvent solubility is enhanced, whereby the generation of particles is inhibited during the preservation. 0074 With respect to the alkyl group represented by R6c and R7c, the same alkyl groups as in R1c to R5c can be enumerated. Examples of the aryl group include an aryl group having from 6 to 14 carbon atoms (such as a phenyl group). 0075 As the alkyl group represented by Rx and Ry, the same alkyl groups as in R1c to R5c can be enumerated. 0076 As the 2-oxyalkyl group can be enumerated the alkyl groups as in R1c to R5c, in which, however, >CO is present at the 2-position thereof. 0077 With respect to the alkoxy group in the alkoxy-carbonylmethyl group, the same alkoxy groups as in R1c to R5c can be enumerated. 0078 As the group formed when Rx and Ry are taken together can be enumerated a butylene group and a pentylene group. 0079 In the compound represented by the general formula (A2I), the stereostructure is fixed by the formation of a ring, whereby the photo-decomposability is enhanced. With respect to the case where any two of R1c to R7c are taken together to form a ring structure, the case where any one of R1c to R5c and any one of R6c and R7c are taken together to become a simple bond or a connecting group, thereby forming a ring is preferred. Especially, the case where R5c and R6c or R7c are taken together to become a simple bond or a connecting group, thereby forming a ring is preferred. 0080 Examples of the connecting group include an optionally substituted alkylene group, an optionally substituted alkenylene group, O, S, CO, CONR (wherein R represents a hydrogen atom, an alkyl group, or an acyl group), and a group comprising a combination of two or more of these groups, with an optionally substituted alkylene group, an oxygen atom-containing alkylene group and a sulfur atom-containing alkylene group being preferred. Examples of the substituent include an alkyl group (preferably having from 1 to 5 carbon atoms), an aryl group (preferably from 6 to 10 carbon atoms, such as a phenyl group), and an acyl group (such as ones having from 2 to 11 carbon atoms). 0081 Further, a connecting group for forming a from 5-membered to 7-membered ring, such as a methyl group, an ethylene group, a propylene group, CH2O, and CH2S, is preferred, with a connecting group for forming a 6-membered ring, such as an ethylene group, CH2O, and CH2S, being particularly preferred. By forming the 6-membered ring, a carbonyl plane becomes more perpendicular to the CS -bond, whereby the photo-decomposability is enhanced by the orbital interaction. 0082 The compound may be a compound having two or more structures represented by the formula (A2I), bound to each other at any one of the positions of R1c to R7c and Rx and Ry via a simple bond or a connecting group. 0083 X preferably represents a sulfonic anion, and more preferably an alkanesulfonic anion substituted with a fluorine atom at the 1-position thereof, or a benzenesulfonic acid substituted with an electron attractive group. The alkane moiety of the alkanesulfonic anion may be substituted with a substituent such as an alkoxy group (such as ones having from 1 to 8 carbon atoms) and a perfluoroalkoxy group (such as ones having 1 to 8 carbon atoms). Examples of the electron attractive group include a chlorine atom, a bromine atom, a nitro group, a cyano group, an alkoxycarbonyl group, an acyloxy group, and an acyl group. 0084 More preferably, X represents a perfluoroalkanesulfonic anion having from 1 to 8 carbon atoms, particularly preferably a perfluorooctanesulfonic anion, and most preferably a perfluorobutanesulfonic anion or a trifluoromethanesulfonic anion. By using this compound, the decomposition rate of the acid-decomposable group is enhanced, the sensitivity is superior, and the diffusibility of the generated acid is controlled, whereby the resolving power is enhanced. 0085 Illustrative Examples of the compound having a phenacylsulfonium salt structure, which can be used in the present invention, will be described below, but it should not be construed that the present invention is limited thereto. 13

14

15

16

17

18

19

20

0086 As the compound having a sulfonium salt structure not having an aromatic ring, which generates an acid upon irradiation with actinic rays or radiations, can be enumerated an alkylsulfonium salt compound represented by the following general formula (A2II). 21

0087 In the general formula (A2II), R1b to R3b each independently represents an alkyl group, and the alkyl group may be a 2-oxoalkyl group having >CO at the 2-position thereof; two of R1b to R3b may be taken together to form a ring structure; and X represents an anion. The alkyl group represented by R1b to R3b may be linear, branched or cyclic. Preferred examples include a linear or branched alkyl group having from 1 to 10 carbon atoms (such as a methyl group, an ethyl group, a propyl group, a butyl group, and a pentyl group) and a cyclic alkyl group having from 3 to 10 carbon atoms (such as a cyclopentyl group, a cyclohexyl group, and a norbornyl group). 0088 The 2-oxoalkyl group represented by R1b to R3b may be linear, branched or cyclic. Preferred examples the foregoing alkyl groups in which, however, >CO is present at the 2-position thereof. 0089 R1b to R3b may be further substituted with a halogen atom, an alkoxy group (such as ones having from 1 to 5 carbon atoms) a hydroxyl group, or a nitro group. 0090 Two of R1b to R3b may be taken together to form a ring structure. The ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group therein. As the group formed when two R1b to R3b are taken together can be enumerated an alkylene group (such as a butylene group and a pentylene group). 0091 From the viewpoint of photo reactivity, a group having a carbon-carbon double bond or a carbon-oxygen double bond may be present in the alkyl chain of any one of R1b to R3b. 0092 For example, X represents a sulfonic anion, and preferably an alkanesulfonic anion substituted with a fluorine atom at the 1-position thereof, or a benzenesulfonic acid substituted with an electron attractive group. More preferably, X represents a perfluoroalkanesulfonic anion having from 1 to 8 carbon atoms, and most preferably a perfluorobutanesulfonic anion or a a perfluorooctaine sulfonic anion. By using this compound, the decomposition rate of the acid-decomposable group is enhanced, the sensitivity is superior, and the diffusibility of the generated acid is controlled, whereby the resolving power is enhanced. 0093 Examples of the electron attractive group include a chlorine atom, a bromine atom, a nitro group, a cyano group, an alkoxycarbonyl group, an acyloxy group, and an acyl group. 0094 At least one of R1b to R3b of the compound represented by the general formula (A2II) may take a structure bonding to at least one of R1b to R3b of other compound represented by the general formula (A2II). 0095 Illustrative Examples of the compound having a alkylsulfonium salt structure, which can be used in the present invention, will be described below, but it should not be construed that the present invention is limited thereto. 22

23

24

0096 As the compound to generate an aromatic sulfonic acid substituted with at least one fluorine atom and/or a group having at least one fluorine atom, upon irradiation with actinic rays or radiations can be enumerated a compound to generate an aromatic sulfonic acid substituted with at least one fluorine atom, a compound to generate an aromatic sulfonic acid substituted with a group having at least one fluorine atom, and a compound to generate an aromatic sulfonic acid substituted with both of at least one fluorine atom and a group having at least one fluorine atom. Examples of the aromatic sulfonic acid include benzenesulfonic acid, naphthalene-sulfonic acid, and anthracenesulfonic acid. 0097 As the component (A) are particularly preferable compounds represented by the following general formulae (A1I) to (A1III). 25

0098 In the foregoing formulae, R1 to R37, which may be the same or different, each independently represents a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a hydroxyl group, a halogen atom, or an SR38 group; R38 represents a linear, branched or cyclic alkyl group or an aryl group; two or more of R1 to R15, R16 to R27, or R28 to R37 may be taken together to form a ring containing one or two or more members selected from a simple bond, carbon, oxygen, sulfur, and nitrogen; and X represents an anion of an aromatic sulfonic acid such as benzenesulfonic acid, naphthalenesulfonic acid, and anthracenesulfonic acid, having at least one member selected from at least one fluorine atom, a linear, branched or cyclic alkyl group substituted with at least one fluorine atom, a linear, branched or cyclic alkoxy group substituted with at least one fluorine atom, an acyl group substituted with at least one fluorine atom, an acyloxy group substituted with at least one fluorine atom, an alkyl- or arylsulfonyl group containing at least one fluorine atom, an alkyl- or arylsulfonyloxy group containing at least one fluorine atom, an alkyl- or arylsulfonylamino group containing at least one fluorine atom, an aryl group substituted with at least one fluorine atom, an aralkyl group substituted with at least one fluorine atom, and an alkoxycarbonyl group substituted with at least one fluorine atom. 0099 In the general formulae (A1I) to (A1III), examples of the linear or branched alkyl group represented by R1 to R38 include ones having from 1 to 4 carbon atoms, which may be substituted, such as a methyl group, an ethyl group, a propyl group, n-butyl group, a sec-butyl group, and a t-butyl group. Examples of the cyclic alkyl group represented by R1 to R38 include ones having from 3 to 8 carbon atoms, which may be substituted, such as a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group. 0100 Examples of the linear or branched alkoxy group represented by R1 to R37 include ones having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a hydroxyethoxy group, a propoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, and a t-butoxy group. 0101 Examples of the cyclic alkoxy group represented by R1 to R37 include a cyclopropyloxy group, a cyclopentyloxy group, and a cyclohexyloxy group. 0102 Examples of the halogen atom represented by R1 to R37 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. 0103 Examples of the aryl group represented by R38 include ones having from 6 to 14 carbon atoms, which may be substituted, such as a phenyl group, a tolyl group, a methoxyphenyl group, and a naphthyl group. 0104 Examples of the substituent include an alkoxy group having from 1 to 4 carbon atoms, a halogen atom (such as a fluorine atom, a chlorine atom, and an iodine atom), an aryl group having from 6 to 10 carbon atoms, an alkenyl group having from 2 to 6 carbon atoms, a cyano group, a hydroxyl group, a carboxy group, an alkoxycarbonyl group, and a nitro group. 0105 Examples of the ring containing one or two or more members selected from a simple bond, carbon, oxygen, sulfur, and nitrogen, which is formed when two or more of R1 to R15, R16 to R27, or R28 to R37 are taken together, include a furan ring, a dihydrofuran ring, a pyran ring, a trihydropyran ring, a thiophene ring, and a pyrrole ring. 0106 In the general formulae (A1I) to (A1III), X represents an anion of an aromatic sulfonic acid such as benzenesulfonic acid, naphthalenesulfonic acid, and anthracenesulfonic acid, having at least one member selected from at least one fluorine atom, a linear, branched or cyclic alkyl group substituted with at least one fluorine atom, a linear, branched or cyclic alkoxy group substituted with at least one fluorine atom, an acyl group substituted with at least one fluorine atom, an acyloxy group substituted with at least one fluorine atom, an alkyl- or arylsulfonyl group containing at least one fluorine atom, an alkyl- or arylsulfonyloxy group containing at least one fluorine atom, an alkyl- or arylsulfonylamino group containing at least one fluorine atom, an aryl group substituted with at least one fluorine atom, an aralkyl group substituted with at least one fluorine atom, and an alkoxycarbonyl group substituted with at least one fluorine atom. 0107 As the linear, branched or cyclic alkyl group represented by X are preferable ones having from 1 to 12 carbon atoms, which are substituted with from 1 to 25 fluorine atoms. Specific examples include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, a 2,2,2-trifluoroethyl group, a heptafluoropropyl group, a heptafluoroisopropyl group, a perfluorobutyl group, a perfluorooctyl group, a perfluorododecyl group, and a perfluorocyclohexyl group. Of these is preferable a perfluoroalkyl group having from 1 to 4 carbon atoms, all hydrogen atoms of which are substituted with a fluorine atom. 0108 As the linear, branched or cyclic alkoxy group represented by X are preferable ones having from 1 to 12 carbon atoms, which are substituted with from 1 to 25 fluorine atoms. Specific examples include a trifluoromethoxy group, a pentafluoroethoxy group, a pentafluoroisopropyloxy group, a perfluorobutoxy group, a perfluorooctyloxy group, a perfluorododecyloxy group, and a perfluorocyclohexyloxy group. Of these is preferable a perfluoroalkoxy group having from 1 to 4 carbon atoms, all hydrogen atoms of which are substituted with a fluorine atom. 0109 As the acyl group represented by X are preferable ones having from 2 to 12 carbon atoms, which are substituted with from 1 to 23 fluorine atoms. Specific examples include a trifluoroacetyl group, a fluoroacetyl group, a pentafluoropropionyl group, and a pentafluorobenzoyl group. 0110 As the acyloxy group represented by X are preferable ones having from 2 to 12 carbon atoms, which are substituted with from 1 to 23 fluorine atoms. Specific examples include a trifluoroacetoxy group, a fluoroacetoxy group, a pentafluoropropionyloxy group, and a pentafluorobenzoyloxy group. 0111 As the alkyl- or arylsulfonyl group represented by X are preferable ones having from 1 to 12 carbon atoms, which contain from 1 to 25 fluorine atoms. Specific examples include a trifluoromethanesulfonyl group, a pentafluoroethanesulfonyl group, a perfluorobutanesulfonyl group, a perfluorooctanesulfonyl group, a pentafluorobenzenesulfonyl group, and a 4-trifluoromethylbenzenesulfonyl group. 0112 As the alkyl- or arylsulfonyloxy group represented by X are preferable ones having from 1 to 12 carbon atoms, which contain from 1 to 25 fluorine atoms. Specific examples include a trifluoromethanesulfonyloxy group, a perfluorobutanesulfonyloxy group, and a 4-trifluoromethylbenzenesulfonyloxy group. 0113 As the alkyl- or arylsulfonylamino group represented by X are preferable ones having from 1 to 12 carbon atoms, which contain from 1 to 25 fluorine atoms. Specific examples include a trifluoromethanesulfonylamino group, perfluorobutanesulfonylamino group, a perfluorooctanesulfonylamino group, and a pentafluorobenzenesulfonylamino group. 0114 As the aryl group represented by X are preferable ones having from 6 to 14 carbon atoms, which are substituted with from 1 to 9 fluorine atoms. Specific examples include a pentafluorophenyl group, a 4-trifluoromethylphenyl group, a pentafluoronaphthyl group, a nonafluoroanthranyl group, a 4-fluorophenyl group, and a 2,4-difluorophenyl group. 0115 As the aralkyl group represented by X are preferable ones having from 7 to 10 carbon atoms, which are substituted with from 1 to 15 fluorine atoms. Specific examples include a pentafluorophenylmethyl group, a pentafluorophenylethyl group, a perfluorobenzyl group, and a perfluorophenethyl group. 0116 As the alkoxycarbonyl group represented by X are preferable ones having from 2 to 13 carbon atoms, which are substituted with from 1 to 25 fluorine atoms. Specific examples include a trifluoromethoxycarbonyl group, a pentafluoroethoxycarbonyl group, a pentafluorophenoxycarbonyl group, a perfluorobutoxycarbonyl group, and a perfluorooctyloxycarbonyl group. 0117 Most preferred examples of X include a benzenesulfonic anion substituted with a fluorine atom and a benzenesulfonic anion substituted with a trifluoromethyl group. Of these are particularly preferable a pentafluorobenzenesulfonic anion, a 2-, 3- or 4-trifluoromethylbenzenesulfonic anion, and a 3,5-bistrifluoromethylbenzenesulfonic anion. 0118 The aromatic sulfonic acid having a fluorine-containing substituent may be further substituted with, for example, a linear, branched or cyclic alkoxy group, an acyl group, an acyloxy group, a sulfonyl group, a sulfonyloxy group, a sulfonylamino group, an aryl group, an aralkyl group, an alkoxycarbonyl group (the range of carbon atoms of these groups is the same as defined above), a halogen atom (excluding a fluorine atom), a hydroxyl group, or a nitro group. 0119 Preferred Illustrative Examples of the component (A) represented by the general formula (A1I) will be described below. 26

27

28

29

30

0120 Preferred Illustrative Examples of the component (A) represented by the general formula (A1II) will be described below. 31

32

0121 Preferred Illustrative Examples of the component (A) represented by the general formula (A1III) will be described below. 33

34

0122 Compounds represented by the following general formulae (A1IV) to (A1VII) are also preferred as the component (A) of the present invention. 35

0123 In the general formulae (A1IV) to (A1VII), Ra and Rb, which may be the same or different, each independently represents an optionally substituted linear, branched or cyclic alkyl group, an optionally substituted aryl group, an optionally heteroaryl group, or an optionally substituted aralkyl group, provided that at least one of Ra and Rb represents a phenyl group, a naphthalene group, or an anthracene group, each of which is substituted with at least one fluorine atom and/or a group having at least one fluorine atom; Rc represents a phenyl group, a naphthalene group, or an anthracene group, each of which is substituted with at least one fluorine atom and/or a group having at least one fluorine atom; Rd represents an optionally substituted linear, branched or cyclic alkyl group, an optionally substituted aryl group, an optionally heteroaryl group, or an optionally substituted aralkyl group; R represents a hydrogen atom, an optionally substituted linear, branched or cyclic alkyl group, a nitro group, or an alkoxy group; and A represents a substituted or unsubstituted alkylene group, arylene group or alkenylene group. 0124 Preferred Illustrative Examples of the component (A) represented by the general formulae (A1IV) to (A1VII) will be described below. 36

37

38

0125 A compound represented by the following general formula (A1VIII) is also preferred as the component (A) of the present invention. 39

0126 In the general formula (A1VIII), R1c to R7c, Rx, and Ry are respectively synonymous with R1c to R7c, Rx, and Ry in the general formula (A2I) as described later. 0127 In the general formula (A1VIII), X is synonymous with X in the foregoing general formulae (A1I) to (A1III). 0128 Preferred Illustrative Examples of the component (A) represented by the general formula (A1VIII) will be described below. 40

0129 Synthesis examples of representative photo acid generators will be described below. Other photo acid generators can be synthesized in the same manner as in these synthesis examples. 0130 (Synthesis of Tetramethylammonium Pentafluorobenzenesulfonate) 0131 Pentafluorobenzenesulfonyl chloride (25 g) was dissolved in 100 mL of methanol under ice cooling, and 100 g of a 25% tetramethylammonium hydroxide aqueous solution was gradually added to the solution. The mixture was stirred at room temperature for 3 hours to obtain a solution of tetramethylammonium pentafluorobenzenesulfonate. This solution was used for salt exchange with a sulfonium salt and an iodonium salt. 0132 (Synthesis of Triphenylsulfonium Pentafluorobenzenesulfonate: Synthesis of Illustrative Example (A1I-1)) 0133 Diphenyl sulfoxide (50 g) was dissolved in 800 mL of benzene, 200 g of aluminum chloride was added to the solution, and the mixture was refluxed for 24 hours. The reaction mixture was gradually poured into 2 L of water, 400 mL of concentrated hydrochloric acid was added thereto, and the mixture was heated at 70 C. for 10 minutes. The resulting aqueous solution was rinsed with 500 mL of ethyl acetate, and after filtration, 200 g of ammonium iodide dissolved in 400 mL of water was added thereto. 0134 A deposited powder was collected by filtration, rinsed successively with water and ethyl acetate, and then dried to obtain 70 g of triphenylsulfonium iodide. 0135 Triphenylsulfonium iodide (30.5 g) was dissolved in 1,000 mL of methanol, 19.1 g of silver oxide was added to the solution, and the mixture was stirred at room temperature for 4 hours. The resulting solution was filtered, and an excessive amount of the tetramethylammonium pentafluorobenzenesulfonate as synthesized above was added thereto. The reaction mixture was concentrated and dissolved in 500 mL of dichloroethane. The solution was rinsed successively with a 5% tetramethylammonium hydroxide aqueous solution and water. An organic phase was dried over anhydrous sodium sulfate and concentrated to obtain triphenylsulfonium pentafluorobenzenesulfonate. 0136 (Synthesis of Triarylsulfonium Pentafluorobenzenesulfonates: Synthesis of mixture of Illustrative Examples (A1I-9) and (A1II-1)) 0137 In 500 mL of water was dissolved 50 g of a triarylsulfonium chloride (50% triphenylsulfonium chloride aqueous solution, made by Fluka), and an excessive amount of a solution of tetramethylammonium pentafluorobenzenesufonate was added to the solution to deposit an oily substance. A supernatant was removed by decantation, and the obtained oily substance was rinsed with water and dried to obtain a triarylsulfonium pentafluorobenzenesulfonate (containing Illustrative Examples (A1I-9) and (A1II-1) as major components) 0138 (Synthesis of di(4-t-amylphenyl)iodonium Pentafluorobenzenesulfonate: Synthesis of Illustrative Example (A1III-1)) 0139 To a mixture of 60 g of t-amylbenzene, 39.5 g of potassium iodide, 81 g of acetic anhydride, and 170 mL of dichloromethane was gradually added dropwise 66.8 g of concentrated sulfuric acid under ice cooling. After stirring under ice cooling for 2 hours, the mixture was further stirred at room temperature for 10 hours. To the reaction mixture was added 500 mL of water under ice cooling, and the mixture was extracted with dichloromethane. An organic phase was rinsed successively with sodium hydrogencarbonate and water and then concentrated to obtain di(4-t-amylphenyl)iodonium sulfate. This sulfate was added to an excessive amount of a solution of tetramethylammonium pentafluorobenzenesulfonate. To this solution was added 500 mL of water, and the mixture was extracted with dichloromethane. An organic phase was rinsed successively with a 5% tetramethylammonium hydroxide aqueous solution and water and then concentrated to obtain di(4-t-amylphenyl)iodonium pentafluorobenzenesulfonate. 0140 The compound (photo acid generator) to generate an acid upon irradiation with actinic rays or radiations, as represented by the following general formula (SI), which is contained in the composition of the present invention, will be described below. 41

0141 In the general formula (SI), examples of the alkyl group represented by Rs4 to Rs6 include ones having from 1 to 25 carbon atoms, which may be substituted, such as a methyl group, an ethyl group, a propyl group, n-butyl group, an isopropyl group, a sec-butyl group, a t-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a t-amyl group, a decanyl group, a dodecanyl group, and a hexadecanyl group. Examples of the cycloalkyl group represented by Rs4 to Rs6 include ones having from 3 to 25 carbon atoms, which may be substituted, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a cyclododecanyl group, and a cyclohexadecanyl group. Examples of the alkoxy group represented by Rs4 to Rs6 include ones having from 1 to 25 carbon atoms, which may be substituted, such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, a t-butoxy group, a pentyloxy group, a t-amyloxy group, an n-hexyloxy group, an n-octyloxy group, and an n-dodecaneoxy group. 0142 Examples of the alkoxycarbonyl group represented by Rs4 to Rs6 include ones having from 2 to 25 carbon atoms, which may be substituted, such as a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, an isopropoxycarbonyl group, an n-butoxycarbonyl group, an isobutoxycarbonyl group, a sec-butoxycarbonyl group, a t-butoxycarbonyl group, a pentyloxycarbonyl group, a t-amyloxycarbonyl group, an n-hexyloxycarbonyl group, an n-octyloxycarbonyl group, and an n-dodecaneoxycarbonyl group. Examples of the acyl group represented by Rs4 to Rs6 include ones having from 1 to 25 carbon atoms, which may be substituted, such as a formyl group, an acetyl group, a butyryl group, a valeryl group, a hexanoyl group, an octanoyl group, a t-butylcarbonyl group, and a t-amylcarbonyl group. Examples of the acyloxy group represented by Rs4 to Rs6 include ones having from 2 to 25 carbon atoms, which may be substituted, such as an acetoxy group, an ethylyloxy group, a butyryloxy group, a t-butyryloxy group, a t-amylyloxy group, an n-hexanecarbonyloxy group, an n-octanecarbonyloxy group, an n-dodecanecarbonyloxy group, and an n-hexadecanecarbonyloxy group. Examples of the halogen atom represented by Rs4 to Rs6 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. 0143 Examples of the substituent on these groups include an alkoxy group having from 1 to 4 carbon atoms, a halogen atom (such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom), an acyl group having from 2 to 5 carbon atoms, an acyloxy group having from 2 to 5 carbon atoms, a cyano group, a hydroxyl group, a carboxy group, an alkoxycarbonyl group having from 2 to 5 carbon atoms, and a nitro group. 0144 When (1mn)1, then R34 represents an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted alkoxy group, an optionally substituted alkoxycarbonyl group, an optionally substituted acyl group, or an optionally substituted acyloxy group. In this case, Rs4 preferably has 2 or more carbon atoms, and more preferably 4 or more carbon atoms. 0145 Among them, as the alkyl group represented by Rs4 to Rs6 are preferable a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a t-butyl group, an n-pentyl group, a t-amyl group, an n-hexyl group, an n-octyl group, and a decanyl group, each of which may be substituted; as the cycloalkyl group represented by Rs4 to Rs6 are preferable a cyclohexyl group, a cyclooctyl group, and a cyclododecanyl group, each of which may be substituted; as the alkoxy group represented by Rs4 to Rs6 are preferable a methoxy group, an ethoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a t-butoxy group, a pentyloxy group, a t-amyloxy group, an n-hexyloxy group, an n-octyloxy group, and an n-dodecaneoxy group, each of which may be substituted; as the alkxoycarbonyl group represented by Rs4 to Rs6 are preferable a methoxycarbonyl group, an ethoxycarbonyl group, an isopropoxycarbonyl group, an n-butoxycarbonyl group, a sec-butoxycarbonyl group, a t-butoxycarbonyl group, a pentyloxycarbonyl group, a t-amyloxycarbonyl group, an n-hexyloxycarbonyl group, an n-octyloxycarbonyl group, and an n-dodecaneoxycarbonyl group, each of which may be substituted; as the acyl group represented by Rs4 to Rs6 are preferable a formyl group, an acetyl group, a butyryl group, a valeryl group, a hexanoyl group, an octanoyl group, a t-butylcarbonyl group, and a t-amylcarbonyl group, each of which may be substituted; and as the acyloxy group represented by Rs4 to Rs6 are preferable an acetoxy group, an ethylyloxy group, a butyryloxy group, a t-butyryloxy group, a t-amylyloxy group, an n-hexanecarbonyloxy group, and an n-octanecarbonyloxy group, each of which may be substituted. 0146 More preferably, specific examples of the substituents Rs4 to Rs6 include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a t-butyl group, an n-pentyl group, a t-amyl group, an n-hexyl group, an n-octyl group, a cyclohexyl group, a methoxy group, an ethoxy group, an isopropoxy group, an n-butoxy group, a t-butoxy group, a pentyloxy group, a t-amyloxy group, a hexyloxy group, an n-octyloxy group, a methoxycarbonyl group, an ethoxycarbonyl group, an n-butoxycarbonyl group, a t-butoxycarbonyl group, a t-amyloxycarbonyl group, a hexyloxycarbonyl group, an n-octyloxycarbonyl group, a formyl group, an acetyl group, a butyryl group, a hexanoyl group, an octanoyl group, a t-butylcarbonyl group, a t-amylcarbonyl group, an acetoxy group, an ethylyloxy group, a butyryloxy group, a t-butyryloxy group, a t-amylyloxy group, an n-hexanecarbonyloxy group, an n-octanecarbonyloxy group, a hydroxyl group, a chlorine atom, a bromine atom, and a nitro group. 0147 These groups may be substituted. Preferred examples of the substituent include a methoxy group, an ethoxy group, a t-butoxy group, a chlorine atom, a bromine atom, a cyano group, a hydroxyl group, a methoxycarbonyl group, an ethoxycarbonyl group, a t-butoxycarbonyl group, and a t-amyloxycarbonyl group. 0148 l, m and n each presents from 1 to 3. 0149 In the sulfonium compound represented by the general formula (SI) to be used in the present invention, a sulfonic acid having a specific structure, RSO3 as described above is used as a counter anion, X. As the aliphatic hydrocarbon group represented by R are preferable an optionally substituted linear or branched alkyl group and an optionally substituted cyclic alkyl group, each having from 1 to 20 carbon atoms. As the aromatic hydrocarbon group represented by R is preferable an optionally substituted aromatic group having from 6 to 14 carbon atoms. 0150 Examples of the alkyl group represented by R include a methyl group, an ethyl group, a propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-octyl group, a 2-ethylhexyl group, a decyl group, and a dodecyl group, each of which may be substituted; and examples of the cyclic alkyl group represented by R include a cyclopentyl group, a cylohexyl group, a cyclooctyl group, a cyclododecyl group, an adamantyl group, a norbornyl group, a camphor group, a tricyclodecanyl group, and menthyl group, each of which may be substituted. Examples of the aromatic group include a phenyl group and a naphthyl group, each of which may be substituted. 0151 As the substituent are preferable an alkyl group, an alkoxy group, and an alkoxycarbonyl group, each having from 1 to 15 carbon atoms, and a halogen atom. Specific examples include a methyl group, t-butyl group, a methoxy group, an ethoxy group, a t-butoxy group, a chlorine atom, a bromine atom, a cyano group, a hydroxyl group, a methoxycarbonyl group, an ethoxycarbonyl group, a t-butoxycarbonyl group, and a t-amyloxycarbonyl group. 0152 Specific examples of R include a methyl group, a trilfuoromethyl group, an ethyl group, a pentafluoroethyl group, a 2,2,2-trifluoroethyl group, an n-propyl group, an n-butyl group, a nonafluorobutyl group, an n-pentyl group, an n-hexyl group, an n-octyl group, a heptadecafluorooctyl group, a 2-ethylhexyl group, a decyl group, a dodecyl group, a cyclopentyl group, a cyclohexyl group, a camphor group, a phenyl group, a naphthyl group, a pentafluorophenyl group, a p-toluyl group, a p-fluorophenyl group, a p-chlorophenyl group, a p-hydroxyphenyl group, a p-methoxyphenyl group, a dodecylphenyl group, a mesityl group, a triisopropylphenyl group, a 4-hydroxy-1-naphthyl group, and a 6-hydroxy-2-naphthyl group. 0153 More preferably, specific examples of R include a methyl group, a trilfuoromethyl group, an ethyl group, a pentafluoroethyl group, a 2,2,2-trifluoroethyl group, an n-butyl group, a nonafluorobutyl group, an n-hexyl group, an n-octyl group, a heptadecafluorooctyl group, a 2-ethylhexyl group, a camphor group, a phenyl group, a naphthyl group, a pentafluorophenyl group, a p-toluyl group, a p-fluorophenyl group, a p-chlorophenyl group, a p-methoxyphenyl group, a dodecylphenyl group, a mesityl group, a triisopropylphenyl group, a 4-hydroxy-1-naphthyl group, and a 6-hydroxy-2-naphthyl group. 0154 The total sum of carbon atoms of the acid as generated is preferably from 1 to 30, more preferably from 1 to 28, and further preferably from 1 to 25. When the total sum of carbon atoms of the acid is less than 1, the pattern formation may possibly be hindered such that the acid becomes in a t-top shape, whereas when it exceeds 30, the development residue is possibly generated, and hence, such is not preferred. 0155 Illustrative Examples of the compound represented by the general formula (SI) will be described below, but it should not be construed that the present invention is limited thereto. These compounds may be used singly or in admixture of two or more thereof. 42

43

44

45

46

0156 An addition amount of the photo acid generator represented by the general formula (SI) is usually in the range of from 0.001 to 20% by weight, preferably from 0.01 to 15% by weight, and more preferably from 0.1 to 10% by weight on a basis of the solids content in the composition. When the addition amount of the photo acid generator is less than 0.001% by weight, the sensitivity becomes low, whereby the pattern formation is liable to become difficult. On the other hand, when it exceeds 20% by weight, the light absorption of the resist becomes too high, whereby the profile is liable to become worse, or the process (especially, baking) margin or exposure margin is liable to become narrow. 0157 The compound represented by the general formula (SI) can be synthesized by, for example, a method in which a substituted or unsubstituted phenyl sulfoxide is reacted with an aryl Grignard reagent such as an aryl magnesium bromide, and the obtained triarylsulfonium halide is subjected to salt exchange with a corresponding sulfonic acid. 0158 Further, the compound represented by the general formula (SI) can be synthesized by, for example, a method in which a substituted or unsubstituted phenyl sulfoxide is condensed and subjected to salt exchange with a corresponding aromatic compound in the presence of an acid catalyst such as methanesulfonic acid/diphosphorus pentoxide and aluminum chloride, or a method in which a diaryliodonium salt and a diaryl sulfide are condensed and subjected to salt exchange in the presence of a catalyst such as copper acetate. 0159 The salt exchange can be carried out by a method in which a halide is first introduced and then exchanged to a sulfonate using a silver reagent such as silver oxide, or by using an ion exchange resin. As the sulfonic acid or sulfonate that is used for the salt exchange, commercially available materials can be used. Alternatively, it can be obtained by hydrolysis of a commercially available sulfonic halide. 0160 The foregoing component (A) may be used singly or in admixture of two or more thereof. 0161 The total amount of the component (A) is usually from 0.1 to 20% by weight, preferably from 0.3 to 15% by weight, and more preferably from 0.5 to 10% by weight on a basis of the solids content of the positive-working photosensitive composition according to the present invention. 0162 Especially, in the case where the component (A) is a combination of at least one of the compound (phenacylsulfonium salt) represented by the general formula (A2I) and the compound (sulfonium salt not having an aromatic ring) represented by the general formula (A2II) with the aromatic sulfonic acid substituted with at least one fluorine atom and/or a group having at least one fluorine atom, the edge roughness and development defect are improved. 0163 A weight ratio of the both to be added is usually from 1/99 to 99/1, preferably from 5/95 to 95/5, and more preferably from 10/90 to 90/10. 0164 When the compound (photo acid generator) to generate an acid upon irradiation with actinic rays or radiations, which is represented by the general formula (SI), is used as the component (A), an addition amount of other photo acid generator than the component (A), which may be used in combination, is usually 1,000% by weight or less, preferably 700% by weight or less, and more preferably 500% by weight or less on a basis of the photo acid generator represented by the general formula (SI). 0165 In the present invention, a compound other than the foregoing specific component (A), which is decomposed upon irradiation with actinic rays or radiations to generate an acid, may be used in combination. 0166 An amount of the photo acid generator that may be used in combination is usually from 100/0 to 5/95, preferably from 95/5 to 7/93, and more preferably from 90/10 to 10/90 in terms of molar ratio of the total amount of the component (A) to other acid generator. 0167 As the photo acid generator other than the component (A), which can be used in combination, can be properly selected and usedphoto initiators of photo cationic polymerization, photo initiators of photo radical polymerization, light decoloring agents of dyes, light discoloring agents, and compounds to generate an acid by known lights used for microresists (such as ultraviolet rays of from 400 to 200 nm and far ultraviolet rays, and particularly preferably g-rays, h-ryas, i-rays, and KrF excimer laser beams), ArF excimer laser beams, electron beams, X rays, molecular rays, or ion beams, or mixtures thereof. 0168 For example, there can be enumerated onium salts such as diazonium salts, ammonium salts, phosphonium salts, iodonium salts, sulfonium salts, selenonium salts, and arsonium salts, organic halides, organic metal/organic halides, photo acid generators having an o-nitrobenzyl type protective group, compounds that are photo-decomposed to generate a sulfonic acid, represented by iminosulfonate, disulfone compounds, diazoketo sulfones, and diazodisulfone compounds. 0169 Further, polymer compounds in which a group or compound to generate an acid by light is introduced in the main chain or side chains thereof can be used. 0170 In addition, the compounds to generate an acid by light, as described in, for example, V. N. R. Pillai, Synthesis, (1), 1 (1980), A. Abad, et al., Tetrahedron Lett., (47), 4555 (1971), D. H. R. Barton, et al., J. Chem. Soc., (C), 329 (1970), U.S. Pat. No. 3,779,778, and European Patent No. 126,712 can be used. 0171 Among the compounds that are decomposed upon irradiation with actinic rays or radiations to generate an acid, other photo acid generators that are particularly effectively used will be described below. 0172 (1) Oxazole derivative represented by the following general formula (PAG1) or S-triazine derivative represented by the following general formula (PAG2), each of which is substituted with a trihalomethyl group: 47

0173 In the general formulae, R201 represents a substituted or unsubstituted aryl group or alkenyl group; R202 represents a substituted or unsubstituted aryl group, alkenyl group or alkyl group, or C(Y)3; and Y represents a chlorine atom or a bromine atom. 0174 (2) Iodonium salt represented by the following general formula (PAG3) or sulfonium salt represented by the following general formula (PAG4): 48

0175 In the general formulae, Ar1 and Ar2 each independently represents a substituted or unsubstituted aryl group; and R203 R204, and R205 each independently represents a substituted or unsubstituted alkyl group or aryl group. 0176 Z represents a counter anion. Examples of the counter anion represented by Z include perfluoroalkanesulfonic anions such as BF4, AsF6, PF6, SbF6, SiF6, ClO4, and CF3SO3; a pentafluorobenzenesulfonic anion; condensed polynucleic aromatic sulfonic anions such as a naphthalene-1-sulfonic anion; an anthraquinonesulfonic anion; and a sulfonic group-containing dyes. But, it should not be construed that the present invention is limited thereto. 0177 Two of R203, R204, and R205, and Ar1 and Ar2 may be each taken together via a simple bond or a substituent. 0178 Illustrative Examples of these other photo acid generators will be described below, but it should not be construed that the present invention is limited thereto. 49

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0179 In the foregoing formulae, Ph represents a phenyl group. 0180 The onium salts represented by the general formulae (PAG3) and (PAG4) are known and can be synthesized by the methods as described in, for example, U.S. Pat. Nos. 2,807,648 and 4,247,473 and JP-A-53-101,331. 0181 (3) Disulfone derivative represented by the following general formula (PAG5) or iminosulfonate derivative represented by the following general formula (PAG6): 57

0182 In the general formulae, Ar3 and Ar4 each independently represents a substituted or unsubstituted aryl group; R206 represents a substituted or unsubstituted alkyl group or aryl group; and A represents a substituted or unsubstituted alkylene group, alkenylene group or arylene group. 0183 Illustrative Examples of these other photo acid generators will be described below, but it should not be construed that the present invention is limited thereto. 58

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62

0184 (4) Diazodisulfone derivative represented by the following general formula (PAG7): 63

0185 In general formula, R represents a linear, branched or cyclic alkyl group or an optionally substituted aryl group. 0186 Illustrative Examples of these other photo acid generators will be described below, but it should not be construed that the present invention is limited thereto. 64

0187 <Synthesis Examples of Photo Acid Generator>0188 The synthesis examples of representative photo acid generators will be described below. Other photo acid generators can be synthesized in the same manner as in these synthesis examples. 0189 (Synthesis of Tetramethylammonium Pentafluorobenzenesulfonate) 0190 Pentafluorobenzenesulfonyl chloride (25 g) was dissolved in 100 mL of methanol under ice cooling, and 100 g of a 25% tetramethylammonium hydroxide aqueous solution was gradually added to the solution. The mixture was stirred at room temperature for 3 hours to obtain a solution of tetramethylammonium pentafluorobenzenesulfonate. This solution was used for salt exchange with a sulfonium salt and an iodonium salt. 0191 (Synthesis of Phenacyltetrahydrothiophenium Perfluorobutanesulfonate: Synthesis of Illustrative Example (A2I-1)) 0192 In 400 mL of acetonitrile was dissolved 53.2 g of tetrahydrothiophene. To this solution was gradually added a solution of 100 g of phenacyl bromide dissolved in 300 mL of acetonitrile. The mixture was stirred at room temperature for 3 hours to deposit a powder. The reaction mixture was poured into 1,500 mL of ethyl acetate, and the powder was collected by filtration and dried to obtain 137 g of phenacyltetrahydrothiophenium bromide. 0193 Potassium perfluorobutanesulfonate (60 g) was dissolved in a mixed solvent of 200 mL of water and 200 mL of methanol. To this solution was added a solution of 49.5 g of phenacyltetrahydrothiophenium bromide dissolved in 300 mL of water. This aqueous solution was extracted twice with 200 mL of chloroform, and an organic phase was rinsed with water and concentrated to obtain a crude product, to which was then added 300 mL of distilled water. The mixture was heated at 100 C. for 30 minutes and then cooled to deposit a solid. The solid was collected by filtration and re-slurried with diisopropyl ether to obtain 77 g of phenacyltetrahydrothiophenium perfluorobutanesulfonate. 0194 (Synthesis of Phenacyltetrahydrothiophenium Perfluorooctanesulfonate: Synthesis of Illustrative Example (A2I-3)) 0195 Phenacyltetrahydrothiophenium bromide was subjected to salt exchange with perfluorooctanesulfonic acid in the same manner as described above. 0196 (Synthesis of Phenacyltetrahydrothiophenium Trifluoromethanesulfonate: Synthesis of Illustrative Example (A2I-2)) 0197 Phenacyltetrahydrothiophenium bromide was subjected to salt exchange with trifluoromethanesulfonic acid in the same manner as described above. 0198 (Synthesis of Illustrative Example (A2II-11)) 0199 In 100 mL of acetonitrile was dissolved 11.8 g of tetrahydrothiophene. To this solution was gradually added 20 g of 1-bromo-3,3-dimethyl-2-butanone. The mixture was stirred at room temperature for 2 days to deposit a powder. To the reaction mixture was 100 mL of ethyl acetate, and the powder was collected by filtration and rinsed with ethyl acetate, followed by drying to obtain 24 g of 2-oxo-3,3-dimethylbutyltetrahydrothiophenium bromide. 0200 Potassium perfluorobutanesulfonate (10 g) was dissolved in a mixed solvent of 500 mL of water and 100 mL of methanol. To this solution was added a solution of 7.75 g of 2-oxo-3,3-dimethylbutyltetrahydrothiophenium bromide dissolved in 50 mL of methanol. This aqueous solution was extracted twice with 100 mL of chloroform, and an organic phase was rinsed with water and concentrated to obtain an oily material. To this oily material was added ethyl acetate for re-concentration, to obtain a solid. The solid was collected by filtration and re-slurried with diisopropyl ether to obtain 9 g of 2-oxo-3,3-dimethylbutyltetrahydrothiophenium perfluorobutanesulfonate. 0201 2-Oxocyclohexylmethyl(2-norbornyl)sulfonium trifluoromethanesulfonate (A2II-1) can be synthesized according to Synthesis Example 1 of JP-A-8-27102. 0202 2 Acid-Decomposable Resin (Component (B)): 0203 The resin (component (B)) that is used in the present invention is a resin having a repeating unit represented by the following general formula (I) and a repeating unit represented by the following general formula (II), which is decomposed by the action of an acid to increase its solubility in an alkaline developing solution (this resin will be hereunder abbreviated as acid-decomposable resin). 65

0204 In the general formula (I), R1a represents a hydrogen atom or an optionally substituted hydrocarbon group; R2a represents an optionally substituted hydrocarbon group; and R1a and R2a may be taken together to form a ring. 0205 The hydrocarbon group represented by R1a preferably has from 1 to 10 carbon atoms, and particularly preferably from 1 to 5 carbon atoms, and examples thereof include an alkyl group (preferably a methyl group). R1a preferably represents a hydrogen atom or a methyl group. 0206 The hydrocarbon group represented by R2a preferably has from 1 to 20 carbon atoms, and particularly preferably from 1 to 10 carbon atoms, and examples thereof include an alkyl group and a cycloalkyl group. 0207 The hydrocarbon group represented by R1a and R2a may be substituted. The substituent preferably has from 1 to 30 carbon atoms. Examples of the substituent include a hydroxyl group, a halogen atom, an alkoxy group, an acyl group, an acylcarbonyl group, and an acyloxy group. 0208 The ring structure in these substituents may contain a hetero atom or may have a substituent such as a hydroxyl group, an alkyl group (preferably one having from 1 to 5 carbon atoms) and an alkoxy group (preferably one having from 1 to 5 carbon atoms). 0209 Examples of the ring formed when R1a and R2a are taken together include from 4- to 8-membered rings such as a tetrahydrofuran ring and a tetrahydropyran ring. This ring structure may have a substituent as described above. 0210 Specific examples of the repeating unit represented by the general formula (I) will be described below, but it should not be construed that the present invention is limited thereto. 66

0211 The acid-decomposable resin of the present invention further contains a repeating unit represented by the following general formula (II). 67

0212 In the general formula (II), Z represents O or N(R3a); R3a represents a hydrogen atom, a hydroxyl group, an alkyl group, a haloalkyl group, or OSO2R4a; and R4a represents an alkyl group, a haloalkyl group, a cycloalkyl group, or a camphor residue. 0213 The alkyl group represented by R3a and R4a is preferably a linear or branched alkyl group having from 1 to 10 carbon atoms, more preferably a linear or branched alkyl group having from 1 to 6 carbon atoms, and further preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or a t-butyl group. 0214 Examples of the haloalkyl group represented by R3a and R4a include a trifluoromethyl group, a nanofluorobutyl group, a pentadecafluorooctyl group, and a trichloromethyl group. Examples of the cycloalkyl group represented by R4a include a cyclopentyl group, a cyclohexyl group, and a cylooctyl group. 0215 The alkyl group and haloalkyl group represented by R3a and R4a and the cycloalkyl group and camphor residue represented by R4a may be each substituted. Examples of the substituent include a hydroxyl group, a carboxyl group, a cyano group, a halogen atom (such as a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom), an alkoxy group (preferably one having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group), an acyl group (preferably one having from 2 to 5 carbon atoms, such as a formyl group and an acetyl group), an acyloxy group (preferably one having from 2 to 5 carbon atoms, such as an acetoxy group), and an aryl group (preferably one having from 6 to 14 carbon atoms, such as a phenyl group). 0216 Specific exmples of the repeating unit represented by the general formula (II) will be described below, but it should not be construed that the present invention is limited thereto. 68

0217 In the acid-decomposable resin of the present invention, a group that is decomposed by the action of an acid to become alkali-soluble may be contained in the repeating unit represented by the foregoing general formula (I) or (II) or in other repeating unit. 0218 Examples of the group that is decomposed by the action of an acid include groups represented by COOA0 and OB0. Further, examples of the group containing the same include R0COOA0 and ArOB0. 0219 Here, A0 represents C(R01) (R02) (R03), Si(R01) (R02) (R03) C(R04) (R05)OR06, or a lactone group; and B0 represents -A0 or COO-A0. 0220 R01, R02, R03, R04, and R05, may be the same or different, each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, or an aryl group; and R06 represents an alkyl group, a cyclic alkyl group, or an aryl group, provided that at least two of R01 to R03 represent a group other than a hydrogen atom and that two groups of R01 to R03, and R04 to R06 may be taken together to form a ring. R0 represents a simple bond or an optionally substituted aliphatic or aromatic hydrocarbon group having a valence of 2 or more; and Ar represents an aromatic group having a valence of 2 or more, which may be substituted with a monocyclic or polycyclic substituent. 0221 Here, as the alkyl group is preferable one having from 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, and a t-butyl group; as the cycloalkyl group is preferable one having from 3 to 30 carbon atoms, such as a cyclopropyl group, a cyclobutyl group, a cylohexyl group, and an adamantyl group; as the alkenyl group is preferable one having from 2 to 4 carbon atoms, such as a vinyl group, a propenyl group, an allyl group, and a butenyl group; and as the aryl group is preferable one having from 6 to 14 carbon atoms, such as a phenyl group, a xylyl group, a toluyl group, a cumenyl group, a naphthyl group, and an anthracenyl group. As the cyclic alkyl group is enumerated one having from 3 to 30 carbon atoms, and specific examples thereof include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, a norbornyl group, a bornyl group, a tricyclodecanyl group, a dicyclopentenyl group, a norbornane epoxy group, menthyl group, an isomenthyl group, a neomenthyl group, a tetracyclododecanyl group, and a steroid residue. As the aralkyl group is enumerated one having from 7 to 20 carbon atoms, which may be substituted, and specific examples thereof include a benzyl group, a phenethyl group, and a cumyl group. 0222 Examples of the substituent include a hydroxyl group, a halogen atom (such as fluorine, chlorine, bromine, and iodine), a nitro group, a cyano group, the above-described alkyl group, an alkoxy group (such as a methoxy group, an ethoxy group, a hydroxyethoxy group, a propoxy group, a hydroxypropoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, and a t-butoxy group), an alkoxycarbonyl group (such as a methoxycarbonyl group and an ethoxycarbonyl group), an aralkyl group (such as a benzyl group, a phenethyl group, and a cumyl group), an aralkyloxy group, an acyl group (such as a formyl group, an acetyl group, a butyryl group, a benzoyl group, a cyanamyl group, and a valeryl group), an acyloxy group (such as a butyryloxy group), the above-described alkenyl group, an alkenyloxy group (such as a vinyloxy group, a propenyloxy group, an allyloxy group, and a butenyloxy group), the above-described aryl group, an aryloxy group (such as a phenoxy group), and an aryloxycarbonyl group (such as a benzoyloxy group). 0223 As the lactone group are enumerated the following structures. 69

0224 In the formulae, Ra, Rb, and Rc each independently represents a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms, and n represents an integer of from 2 to 4. 0225 In the case where ArF excimer laser beams are used as the exposure source, it is preferred to use a group represented by C (O)X1R0 as the group that is decomposed by the action of an acid. Here, examples of R0 include a tertiary alkyl group (such as a t-butyl group and a t-amyl group), an isobornyl group, a 1-alkoxyethyl group (such as a 1-ethoxyethyl group, a 1-butoxyethyl group, a 1-isobutoxyethyl group, and a 1-cyclohexyloxyethyl group), an alkoxymethyl group (such as a 1-methoxymethyl group and a 1-ethoxymethyl group), a tetrahydropyranyl group, a tetrahydrofuranyl group, a trialkylsilyl-group, a 3-oxocyclohexyl group, and the above-described lactone group. X1 represents an oxygen atom or a sulfur atom, and preferably an oxygen atom. 0226 Especially, it is preferred that the acid-decomposable resin contains a repeating unit having an acid-decomposable group represented by any one of the following general formulae (pI) to (pV). By containing this repeating unit, the image forming properties and the resistance to dry etching are enhanced. 70

0227 In the foregoing formulae, R11 represents a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a sec-butyl group; Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with the carbon atoms; R12 to R16 each independently represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R12 to R14, and any one of R15 and R16 each represents an alicyclic hydrocarbon group; R17 to R21 each independently represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R17 to R21 represents an alicyclic hydrocarbon atom and that any one of R19 and R21 represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms; R22 to R25 each independently represents a linear or branched alkyl group or an alicyclic hydrocarbon group, each having from 1 to 4 carbon atoms, provided that at least one of R22 to R25 represents an alicyclic hydrocarbon atom and that R23 and R24 may be taken together to form a ring. 0228 In the general formulae (pI) to (pV), the alkyl group represented by R12 to R25 is a linear, branched alkyl group having from 1 to 4 carbon atoms, which may be substituted or unsubstituted. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group. 0229 Examples of the substituent of the alkyl group include an alkoxy group having from 1 to 4 carbon atoms, a halogen atom (such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom), an acyl group, an acyloxy group, a cyano group, a hydroxyl group, a carboxy group, an alkoxycarbonyl group, and a nitro group. 0230 The alicyclic hydrocarbon group represented by R11 to R25 and the alicyclic hydrocarbon group formed by Z together with the carbon atoms may be monocyclic or polycyclic. Specifically, the alicyclic hydrocarbon group is a group having a monocyclic, bicyclic, tricyclic or tetracyclic structure having 5 or more carbon atoms, preferably one having from 6 to 30 carbon atoms, and particularly preferably one having from 7 to 25 carbon atoms. The alicyclic hydrocarbon group may be substituted. 0231 Examples of the structure of the alicyclic moiety of the alicyclic hydrocarbon group will be described below. 71

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0232 In the present invention, preferred examples of the alicyclic moiety include an adamntyl group, a noradamntyl group, a decalin residue, a tricyclodecanyl group, a tetracyclododecanyl group, a norbornyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, and a cyclododecanyl group, with an admantyl group, a decalin residue, a norbonyl group, a cedrol group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group, a cyclododecanyl group, and a tricyclodecanyl group being more preferred. 0233 Examples of the alicyclic hydrocarbon group include an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a carboxyl group, and an alkoxycarbonyl group. 0234 Examples of the alkyl group include a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group, with a methyl group, an ethyl group, a propyl group, and an isopropyl group being more preferred. 0235 Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group. 0236 Examples of the alkoxy group include ones having from 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. 0237 Specific examples of the monomer having a repeating unit represented by any one of the foregoing general formulae (pI) to (pV) will be described below. 76

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80

0238 From the standpoint of enhancing the contact hole resolution and the defocus latitude, it is preferred to contain a repeating unit having a lactone residue. From the standpoint of reducing the development defect, it is preferred to contain a repeating unit having an alicyclic lactone residue. 0239 The alicyclic lactone as referred to herein means a structure in which a cyclic hydrocarbon group is condensed with a lactone ring, or a structure in which one of cycloalkane rings of a polycyclic hydrocarbon group (cyclic hydrocarbon ring comprising a combination of two or more cycloalkane rings) is substituted with a lactone ring. 0240 As the lactone residue is enumerated (a1) butyrolactone; and as the alicyclic lactone are enumerated (a2) norbornane lactone, (a3) cyclohexane lactone, and (a4) adamantane lactone. 0241 As the repeating unit (a1) having a lactone residue can be enumerated a repeating unit represented by the following general formula (BL). 81

0242 In the general formula (BL), R1 represents a hydrogen atom or a methyl group; W represents a single group or a combination of two or more groups selected from the group consisting of a simple bond, an alkylene group, an ether group, a thioether group, a carbonyl group, and an ester group; Ra, Rb, Rc, Rd, and Re each independently represents a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms; m and n each independently represents an integer of from 0 to 3; and (mn) is from 2 to 6. 0243 In the general formula (BL), examples of the alkyl group having from 1 to 4 carbon atoms, represented by Ra to Re, include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group. 0244 As the alkylene group represented by W is enumerated a group represented by the following general formula.

C(Rf)(Rg)r

0245 In the formula, Rf and Rg, which may be the same or different, each independently represents a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, or an alkoxy group. As the alkyl group is preferable a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group, with a methyl group, an ethyl group, a propyl group, and an isopropyl group being more preferred. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group. Examples of the alkoxy group include ones having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. r represents an integer of from 1 to 10. 0246 Examples of the substituent of the alkyl group include a carboxyl group, an acyloxy group, a cyano group, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, an alkoxy group, a substituted alkoxy group, an acetylamide group, an alkoxycarbonyl group, and an acyl group. 0247 Examples of the alkyl group include a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclopentyl group. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group. Examples of the substituent of the substituted alkoxy group include an alkoxy group. Examples of the alkoxy group include ones having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the acyloxy group include an acetoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. 0248 Specific examples of the monomer having the repeating unit represented by the general formula (BL) will be described below, but it should not be construed that the present invention is limited thereto. 82

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0249 In the acid-decomposable resin of the present invention, as the monomer of norbornane lactone (a2) and the monomer of cyclohexane lactone (a3) are preferable those having a repeating unit having each of groups represented by the following general formulae (V-1) to (V-2) and (V-3) to (V-4). 0250 As the repeating unit having the norbornane lactone (a2) are enumerated repeating units having a group represented by the following general formula (V-1) or (V-2). 86

0251 In the general formulae (V-1) to (V-2), R1b to R5b each independently represents a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, or an optionally substituted alkenyl group; and two of R1b to R5b may be taken together to form a ring. 0252 As the repeating unit having the norbornane lactone (a3) are enumerated repeating units having a group represented by the following general formula (V-3) or (V-4). 87

0253 In the general formulae (V-3) to (V-4), R1b to R5b each independently represents a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, or an optionally substituted alkenyl group; and two of R1b to R5b may be taken together to form a ring. 0254 In the general formulae (V-1) to (V-4), examples of the alkyl group represented by R1b to R5b include a linear or branched alkyl group, which may be substituted. 0255 The linear or branched alkyl group is preferably a linear or branched alkyl group having from 1 to 12 carbon atoms, and more preferably a linear or branched alkyl group having from 1 to 10 carbon atoms, with a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a t-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group being most preferred. 0256 As the cycloalkyl group represented by R1b to R5b are preferable ones having from 3 to 8 carbon atoms, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. 0257 As the alkenyl group represented by R1b to R5b are preferable ones having from 2 to 6 carbon atoms, such as a vinyl group, a propenyl group, a butenyl group, and a hexenyl group. 0258 As the ring formed when two of R1b to R5b are taken together are enumerated from 3- to 8-membered rings such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, and a cyclooctane ring. 0259 In the general formulae (V-1) to (V-4), R1b to R5b may be each connected to any of the carbon atoms constituting the cyclic skeleton. 0260 Examples of the substituent, with which the foregoing alkyl group, cycloalkyl group or alkenyl group may be substituted, include an alkoxy group having from 1 to 4 carbon atoms, a halogen atom (such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom), an acyl group having from 2 to 5 carbon atoms, an acyloxy group having from 2 to 5 carbon atoms, a cyano group, a hydroxyl group, a carboxy group, an alkoxycarbonyl group having from 2 to 5 carbon atoms, and a nitro group. 0261 As the repeating unit having each of the groups represented by the general formulae (V-1) to (V-4) can be enumerated a repeating unit represented by the following general formula (AI). 88

0262 In the general formula (AI), Rb0 represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group having from 1 to 4 carbon atoms. As the preferred substituent, with which the alkyl group represented by Rb0 may be substituted, are enumerated those enumerated above as the preferred substituent, with which the alkyl group represented by R1b in the general formulae (V-1) to (V-4) may be substituted. 0263 Examples of the halogen atom represented by Rb0 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Rb0 preferably represents a hydrogen atom. 0264 A represents a simple bond, an ether group, an ester group, a carbonyl group, an alkylene group, or a divalent group comprising a combination of these groups. 0265 B2 represents a group represented by any one of the general formulae (V-1) to (V-4). In A, examples of the divalent group comprising a combination are as follows. 89

0266 In the above formulae, Rab and Rbb, which may be the same or different, each independently represents a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, or an alkoxy group. 0267 As the alkyl group is preferable a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group, with a methyl group, an ethyl group, a propyl group, and an isopropyl group being more preferred. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group having from 1 to 4 carbon atoms. 0268 As the alkoxy group can be enumerated ones having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. r represents an integer of from 1 to 10, and preferably from 1 to 4. m represents an integer of from 1 to 3, and preferably 1 or 2. 0269 Specific examples of the repeating unit represented by the general formula (AI) will be described below, but it should not be construed that the present invention is limited thereto. 90

91

92

93

94

95

96

97

0270 As the adamantane lactone (a4) is preferable a repeating unit represented by the following general formula (AL). 98

0271 In the general formula (AL), A represents a single group or a combination of two or more groups selected from the group consisting of a simple bond, an alkylene group, a cycloalkylene group, an ether group, a thioether group, a carbonyl group, and an ester group; and R represents a hydrogen atom, an alkyl group having from 1 to 4 carbon atoms, a cyano group, or a halogen atom. 0272 In the general formula (AL), as the alkylene group represented by A is enumerated a group represented by the following general formula.

C(Rnf)(Rng)r

0273 In the formula, Rnf and Rng, which may be the same or different, each independently represents a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, or an alkoxy group. As the alkyl group is preferable a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group, with a methyl group, an ethyl group, a propyl group, and an isopropyl group being more preferred. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group. Examples of the alkoxy group include ones having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. r represents an integer of from 1 to 10. 0274 In the general formula (AL), examples of the cycloalkylene group represented by A include ones having from 3 to 10 carbon atoms, such as a cyclopentylene group, a cyclohexylene group, and a cyclooctylene group. 0275 The bridged alicyclic ring containing Z may be substituted. Examples of the substituent include a halogen atom, an alkoxy group (preferably one having from 1 to 4 carbon atoms), an alkoxycarbonyl group (preferably one having from 1 to 5 carbon atoms), an acyl group (such as a formyl group and a benzoyl group), an acyloxy group (such as a propylcarbonyloxy group and a benzoyloxy group), an alkyl group (preferably one having from 1 to 4 carbon atoms), a carboxyl group, a hydroxyl group, and an alkylsulfonylsulfamoyl group (such as CONHSO2CH3). The alkyl group as the substituent may be further substituted with, for example, a hydroxyl group, a halogen atom, or an alkoxy group (preferably one having from 1 to 4 carbon atoms). 0276 In the general formula (AL), the oxygen atom of the ester group binding to A may be bound at any position of the carbon atoms constituting the bridged alicyclic ring structure containing Z. 0277 Specific examples of the repeating unit represented by the general formula (AL) will be described below, but it should not be construed that the present invention is limited thereto. 99

100

0278 Further, in the acid-decomposable resin of the present invention, especially from the standpoint of improving the edge roughness, it is preferred to contain a repeating unit represented by the following general formula (III). 101

0279 In the general formula (III), R30 represents a hydrogen atom or a methyl group; and R31 to R33 each independently represents a hydrogen atom, a hydroxyl group, or an alkyl group, provided that at least one of R31 to R33 represents a hydroxyl group. 0280 From the standpoint that a broad exposure margin is obtained during the formation of a hole pattern by under exposure, it is more preferred that in the repeating unit represented by the general formula (III), two of R31 to R33 represent a hydroxyl group. 0281 Specific examples of the repeating unit represented by the general formula (III) will be described below, but it should not be construed that the present invention is limited thereto. 102

0282 In addition, from the standpoint of enhancing the heat resistance and the etching resistance, it is preferred to contain a repeating unit represented by the following general formula (IV). 103

0283 In the general formula (IV), R1 to R4 each independently represents a hydrogen atom, a halogen atom, a cyano group, COOH, an optionally substituted hydrocarbon group, COOR5, C(O)X-A-R6, or a group that is decomposed by the action of an acid; at least two of R1 to R4 may be taken together to form a ring; R5 represents an optionally substituted hydrocarbon group or a lactone residue; R6 represents a hydrogen atom, COOH, COOR5, CN, a hydroxyl group, an optionally substituted alkoxy group, an optionally substituted hydrocarbon group, or a lactone residue; X represents an oxygen atom, a sulfur atom, NHSO2, or NHSO2NH; A represents a single group or a combination of two or more groups selected from the group consisting of a simple bond, an alkylene group, a cycloalkylene group, an ether group, a thioether group, a carbonyl group, an ester group, a sulfonamide group, and N-sulfonylamide group; and n represents 0 or 1. 0284 The structure of the group that is decomposed by the action of an acid is represented by C(O)X1Rp. 0285 In the formula, examples of Rp include a tertiary alkyl group (such as a t-butyl group and a t-amyl group), an isobornyl group, a 1-alkoxyethyl group (such as a 1-ethoxyethyl group, a 1-butoxyethyl group, a 1-isobutoxyethyl group, and a 1-cyclohexyloxyethyl group), an alkoxymethyl group (such as a 1-methoxymethyl group and a 1-ethoxymethyl group), a 3-oxoalkyl group, a tetrapyranyl group, a tetrahydrofuranyl group, a trialkylsilyl ester group, a 3-oxocyclohexyl ester group, a 2-methyl-2-adamantyl group, a mevalonic lactone residue, and a 2-(-butyrolactonyloxycarbonyl)-2-propyl group; and X1 represents an oxygen atom, a sulfur atom, NH, NHSO2, or NHSO2NH. 0286 Examples of the halogen atom represented by R1 to R4 include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. 0287 As the hydrocarbon group represented by R1 to R4, R5, and R6 are preferable a linear, branched or cyclic alkyl group and a bridged hydrocarbon group. 0288 The linear or branched alkyl group is preferably a linear or branched alkyl group having from 1 to 10 carbon atoms, more preferably a linear or branched alkyl group having from 1 to 6 carbon atoms, and further preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or a t-butyl group. 0289 Examples of the cyclic alkyl group and the bridged hydrocarbon group include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, a 2-methyl-2-adamantyl group, a norbornyl group, a bornyl group, an isobornyl group, a tricyclodecanyl group, a dicyclopentenyl group, a norbornane epoxy group, a menthyl group, an isomenthyl group, a neomenthyl group, and a tetracyclodecanyl group. 0290 Examples of the ring formed when at least two of R1 to R4 are taken together include ones having from 5 to 12 carbon atoms, such as a lactone ring, cyclopentene, cyclohexene, cycloheptane, and cyclooctane. 0291 As the alkoxy group represented by R6 are preferable ones having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. 0292 The foregoing hydrocarbon group and alkoxy group may be further substituted. Examples of the substituent include a hydroxyl group, a carboxyl group, a cyano group, a halogen atom (such as a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom), an alkoxy group (preferably one having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group), an acyl group (such as a formyl group and an acetyl group), and an acyloxy group (such as an acetoxy group). 0293 As the alkylene group represented by A is enumerated a group represented by the following general formula.

C(Rb)(Rc)r

0294 In the formula, Rb and Rc, which may be the same or different, each independently represents a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, or an alkoxy group. As the alkyl group is preferable a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group, with a methyl group, an ethyl group, a propyl group, and an isopropyl group being more preferred. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom, and an alkoxy group (preferably one having from 1 to 4 carbon atoms). Examples of the alkoxy group include ones having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom. r represents an integer of from 1 to 10. 0295 As the lactone residue represented by R5 and R6 can be enumerated by a Y group represented by any of the following formulae: 104

0296 In the general formulae, R21 to R30 each independently represents a hydrogen atom or an alkyl group; and a and b each represents 1 or 2. 0297 Examples of the alkyl group represented by R21 to R30 include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group. 0298 The alkyl group represented by R21 to R30 may be substituted. Examples of the substituent include a hydroxyl group, a carboxyl group, a cyano group, a halogen atom (such as a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom), an alkoxy group (preferably one having from 1 to 4 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group), an acyl group (preferably one having from 2 to 5 carbon atoms, such as a formyl group and an acetyl group), an acyloxy group (preferably one having from 2 to 5 carbon atoms, such as an acetoxy group), and an aryl group (preferably from 6 to 14 carbon atoms, such as a phenyl group). 0299 Specific examples of the repeating unit represented by the general formula (IV) will be described below, but it should not be construed that the present invention is limited thereto. 105

106

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112

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0300 The acid-decomposable resin as the component (B) can contain various repeating structural units other than the foregoing repeating units, for the purposes of enhancing the resistance to dry etching and standard development aptitude, the adhesiveness to substrate and the resist profile, and regulating the general characteristics required for resists, such as resolving power, heat resistance, and sensitivity. 0301 As these repeating structural units, repeating structural units corresponding to the monomers as described below can be enumerated, but it should not be construed that the present invention is limited thereto. 0302 By this, it is possible to finely adjust the performance required for the acid-decomposable resin, especially 0303 (1) solubility in coating solvent, 0304 (2) film forming properties (glass transition point), 0305 (3) alkali-development properties, 0306 (4) film thickness reduction (hydrophilicity, hydrophobicity, and selection of alkali-soluble group), 0307 (5) adhesiveness to substrate in unexposed area, and 0308 (6) resistance to dry etching. 0309 Examples of such monomers include compounds having one addition polymerizable unsaturated bond, selected from acrylic esters, methacrylic esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, and vinyl esters. 0310 A content of the repeating unit represented by the general formula (I) in the acid-decomposable resin is preferably from 2 to 50% by mole, more preferably from 4 to 45% by mole, and most preferably from 6 to 40% by mole in the whole of the repeating structural units. 0311 A content of the repeating unit represented by the general formula (II) is preferably from 15 to 60% by mole, more preferably from 20 to 55% by mole, and most preferably from 25 to 50% by mole in the whole of the repeating structural units. 0312 The total sum of the repeating units having the acid-decomposable group is preferably from 20 to 70% by mole, more preferably from 25 to 65% by mole, and most preferably from 30 to 60% by mole in the whole of the repeating structural units. 0313 A content of the repeating unit represented by any of the general formulae (pI) to (pVI) is preferably from 10 to 60% by mole, more preferably from 15 to 50% by mole, and most preferably from 20 to 40% by mole in the whole of the repeating structural units. 0314 A content of the repeating unit represented by the general formula (III) is preferably from 3 to 40% by mole, more preferably from 5 to 35% by mole, and most preferably from 8 to 40% by mole in the whole of the repeating structural units. 0315 A content of the repeating unit represented by the general formula (IV) is preferably from 3 to 40% by mole, more preferably from 5 to 35% by mole, and most preferably from 8 to 40% by mole in the whole of the repeating structural units. 0316 A content of the repeating unit having a lactone residue or an alicyclic lactone is preferably from 5 to 50% by mole, more preferably from 10 to 40% by mole, and most preferably from 12 to 30% by mole in the whole of the repeating structural units. 0317 When the composition according to the present invention is used for ArF exposure, it is preferred from the standpoint of transparency to ArF light that the resin does not have an aromatic group. 0318 The acid-decomposable resin that is used in the present invention can be synthesized in a customary manner (such as radical polymerization). For example, as the general synthesis method, the monomer species are charged at once or on the way of the reaction into a reaction vessel; if desired, the monomers are dissolved in a reaction solvent such as ethers (e.g., tetrahydrofuran, 1,4-dioxane, diisoporpyl ether), ketones (e.g., methyl ethyl ketone, methyl isobutyl ketone), ester solvents (e.g., ethyl acetate), and solvents dissolving the composition according to the present invention therein as described later (e.g., propylene glycol monomethyl ether acetate), to form a uniform solution; and polymerization of the solution is initiated by heating, if desired in an inert gas atmosphere such as nitrogen and argon using a commercially available radical initiator (such as an azo-based initiator and a peroxide). If desired, the initiator is supplemented or dividedly added. After completion of the reaction, the reaction mixture is added to a solvent, and the desired polymer is recovered by a powder or solid recovery method. A reaction concentration is 20% by weight or more, preferably 30% by weight or more, and more preferably 40% by weight or more. A reaction temperature is from 10 C. to 150 C., preferably from 30 C. to 120 C., and more preferably from 50 C. to 100 C. 0319 A weight average molecular weight of the acid-decomposable resin according to the present invention is from 1,000 to 200,000, preferably from 3,000 to 50, 000, and more preferably from 5,000 to 30, 000 in terms of a conversion value to polystyrene by the GPC method. When the weight average molecular weight is less than 1,000, deterioration in heat resistance and resistance to dry etching is found, and hence, such is not so desired. On the other hand, when the weight average molecular weight exceeds 200,000, there are generated undesired results such that the development properties are deteriorated and that the viscosity becomes extremely high, leading to deterioration in film forming properties. 0320 In the positive-working photoresist composition for far ultraviolet exposure according to the present invention, a compounding amount of the acid-decomposable resin according to the present invention in the whole of the composition is preferably from 40 to 99.99% by weight, and more preferably from 50 to 99.97% by weight in the solids content of the total resists. 0321 In the solvent are dissolved the solid components such as the photo acid generator (A) and the resin (B) are dissolved in an amount of preferably from 3 to 25% by weight, more preferably from 5 to 22% by weight, and most preferably from 7 to 20% by weight in terms of solid concentration. 0322 3 Mixed Solvent (Component (C)): 0323 The positive-working photosensitive composition according to the present invention contains a mixed solvent as the component (C). As this mixed solvent is enumerated a mixed solvent containing at least one member selected from propylene glycol monoalkyl ether alkoxylates (sometimes referred to as solvent group A), at least one member selected from propylene glycol monoalkyl ethers, alkyl lactates, and alkyl alkoxypropionates (sometimes referred to as solvent group B), and/or at least one member selected from -butyrolactone, ethylene carbonate, and propylene carbonate (sometimes referred to as solvent group C). That is, as the component (C) can be used a combination of the solvent group A and the solvent group B, a combination of the solvent group A and the solvent group C, and a combination of the solvent group A, the solvent group B and the solvent group C. 0324 Preferred examples of the propylene glycol monoalkyl ether alkoxylates include propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, propylene glycol monoethyl ether acetate, and propylene glycol monoethyl ether propionate. 0325 Preferred examples of the propylene glycol monoalkyl ethers include propylene glycol monomethyl ether and propylene glycol monoethyl ether. Preferred examples of the alkyl lactates include methyl lactate and ethyl lactate. Preferred examples of the alkyl alkoxypropionates include ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, and methyl 3-ethoxypropionate. 0326 A weight ratio of the solvent group A to the solvent group B (A:B) to be used is preferably from 90:10 to 15:85, more preferably from 85:15 to 20:80, and most preferably from 80:20 to 25:75. 0327 A weight ratio of the solvent group A to the solvent group C (A:C) to be used is preferably from 99.9:0.1 to 75:25, more preferably from 99:1 to 80:20, and most preferably from 97:3 to 85:15. 0328 In the case where these three kinds of solvents are combined, a weight ratio of the solvent group C to be used is preferably from 0.1 to 25% by weight, more preferably from 1 to 20% by weight, and most preferably from 3 to 17% by weight of the whole of the solvents. 0329 In the present invention, in the mixed solvent are dissolved the solid components of the composition containing the foregoing respective components are dissolved in an amount of preferably from 3 to 25% by weight, more preferably from 5 to 22% by weight, and most preferably from 7 to 20% by weight in terms of solid concentration. 0330 In the present invention, preferred examples of the combination in the mixed solvent containing the propylene glycol monoalkyl ether carboxylate include: 0331 Propylene glycol monomethyl ether acetatepropylene glycol monomethyl ether; 0332 Propylene glycol monomethyl ether acetateethyl lactate; 0333 Propylene glycol monomethyl ether acetate3-ethoxyethyl propionate; 0334 Propylene glycol monomethyl ether acetate-butyrolactone; 0335 Propylene glycol monomethyl ether acetateethylene carbonate; 0336 Propylene glycol monomethyl ether acetatepropylene carbonate; 0337 Propylene glycol monomethyl ether acetatepropylene glycol monomethyl ether-butyrolactone; 0338 Propylene glycol monomethyl ether acetateethyl lactate-butyrolactone; 0339 Propylene glycol monomethyl ether acetate3-ethoxyethyl propionate-butyrolactone; 0340 Propylene glycol monomethyl ether acetatepropylene glycol monomethyl etherethylene carbonate; 0341 Propylene glycol monomethyl ether acetateethyl lactateethylene carbonate; 0342 Propylene glycol monomethyl ether acetate3-ethoxyethyl propionateethylene carbonate; 0343 Propylene glycol monomethyl ether acetatepropylene glycol monomethyl etherpropylene carbonate; 0344 Propylene glycol monomethyl ether acetateethyl lactate propylene carbonate; and 0345 Propylene glycol monomethyl ether acetate3-ethoxyethyl propionate propylene carbonate. 0346 Of these combinations of solvents are particularly preferable: 0347 Propylene glycol monomethyl ether acetatepropylene glycol monomethyl ether-butyrolactone; 0348 Propylene glycol monomethyl ether acetateethyl lactate-butyrolactone; 0349 Propylene glycol monomethyl ether acetate3-ethoxyethyl propionate-butyrolactone; 0350 Propylene glycol monomethyl ether acetatepropylene glycol monomethyl etherethylene carbonate; 0351 Propylene glycol monomethyl ether acetateethyl lactateethylene carbonate; 0352 Propylene glycol monomethyl ether acetate3-ethoxyethyl propionateethylene carbonate; 0353 Propylene glycol monomethyl ether acetatepropylene glycol monomethyl etherpropylene carbonate; 0354 Propylene glycol monomethyl ether acetateethyl lactatepropylene carbonate; and 0355 Propylene glycol monomethyl ether acetate3-ethoxyethyl propionatepropylene carbonate. 0356 To each of the foregoing mixed solvents of the present invention may be added other nonessential solvent so far as the effects of the present invention are not inhibited. An amount of such other solvent to be added is generally 30 parts by weight or less based on 100 parts by weight of each of the mixed solvents of the present invention. Examples of other solvents include ethylene dichloride, cyclohexanone, cyclopentanone, methyl ethyl ketone, toluene, N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran, and solvents described below, in addition to the solvents as enumerated above as essential solvents of the mixed solvent. 0357 <Acid-Decomposable Dissolution Inhibiting Compound (Component (D))>0358 It is preferred that the positive-working photosensitive composition according to the present invention contains (D) a dissolution inhibiting low-molecular weight compound having a group that is decomposed by the action of an acid to increase its solubility in an alkaline developing solution and having a molecular weight of 3,000 or less (sometimes referred to as acid-decomposable dissolution inhibiting compound (D)). 0359 Especially, in order that the transmission of 220 nm or less is not lowered, an alicyclic or aliphatic compound containing an acid-decomposable group, such as cholic acid derivatives containing an acid-decomposable group as described in Proceeding of SPIE, 2724, 355 (1996), is preferred as the acid-decomposable dissolution inhibiting compound (D). As the acid-decomposable group and the alicyclic structure, the same as in the acid-decomposable resin as described above can be applied. 0360 An amount of the acid-decomposable dissolution inhibiting compound (D) to be added is preferably from 3 to 50% by weight, and more preferably from 5 to 40% by weight on a basis of the solids content of the whole of the composition of the positive-working photosensitive composition. 0361 Specific examples of the acid-decomposable dissolution inhibiting compound (D) will be described below, but it should not be construed that the present invention is limited thereto. 120

0362 <Nitrogen-Containing Basic Compound (Component (E))>0363 In order to reduce the lapsing change in performance from the exposure to the heating, it is preferred that the positive-working photosensitive composition according to the present invention contains (E) a nitrogen-containing basic compound. 0364 As the structure of the nitrogen-containing basic compound (E) are preferable structures as represented by the following general formulae (A) to (E). 121

0365 In the general formula, R250, R251, and R252 each independently represents a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms, an aminoalkyl group having from 1 to 6 carbon atoms, a hydroxyalkyl group having from 1 to 6 carbon atoms, or a substituted or unsubstituted aryl group having from 6 to 20 carbon atoms; and R250 and R251 may be taken together to form a ring. 122

0366 In the general formulae, R253, R254, R255 and R256 each independently represents an alkyl group having 1 to 6 carbon atoms. 0367 Preferred specific examples include substituted or unsubstituted guanidines, substituted or unsubstituted aminopyridines, substituted or unsubstituted aminoalkylpyridines, substituted or unsubstituted aminopyrrolidines, substituted or unsubstituted indazoles, substituted or unsubstituted pyrazoles, substituted or unsubstituted pyrazines, substituted or unsubstituted pyrimidines, substituted or unsubstituted purines, substituted or unsubstituted imidazolines, substituted or unsubstituted pyrazolines, substituted or unsubstituted piperazines, substituted or unsubstituted aminomorpholines, substituted or unsubstituted aminoalkylmorpholines, mono-, di- and trialkylamines, substituted or unsubstituted anilines, substituted or unsubstituted piperidines, and mono- or diethanolamine. Preferred examples of the substituent include an amino group, an aminoalkyl group, an alkylamino group, an aminoaryl group, an arylamino group, an alkyl group, an alkoxy group, an acyl group, an acyloxy group, an aryl group, an aryloxy group, a nitro group, a hydroxyl group, and a cyano group. 0368 Especially preferred compounds are guanidine, 1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, 2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2-(aminomethyl)pyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, 2-amino-5-methylpyridine, 2-amino-6-methylpyridine, 3-aminoethylpyridine, 4-aminoethylpyridine, 3-aminopyrrolidine, piperazine, N-(2-aminoethyl) piperazine, N-(2-aminoethyl)piperidine, 4-amino-2,2,6,6-tetramethylpiperidine, 4-piperidinopiperidine, 2-iminopiperidine, 1-(2-aminoethyl)pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5-amino-3-methyl-1-p-tolylpyrazole, pyrazine, 2-(aminomethyl)-5-methylpyrazine, pyrimidine, 2,4-diaminopyrimidine, 4,6-dihydropyrimidine, 2-pyrazoline, 3-pyrazoline, N-aminomorpholine, N-(2-aminoethyl)morpholine, 1,5-diazabicyclo4.3.0nonan-5-ene, 1,8-diazabicyclo-5.4.0undecan-7-ene, 2,4,5-triphenylimidazole, tri-(n-butyl)amine, tri(n-octyl)amine, N-phenyldiethanolamine, N-hydroxyethylpiperidine, 2,6-diisopropylaniline, and N-cyclohexyl-N-morpholinoethylthiourea. However, it should not be construed that the present invention is limited thereto. 0369 The nitrogen-containing basic compound (E) may be used singly or in admixture of two or more thereof. An amount of the nitrogen-containing basic compound (E) to be used is usually from 0.001 to 10% by weight, and preferably from 0.01 to 5% by weight on a basis of the solids content of the photosensitive resin composition. When the amount of the nitrogen-containing basic compound (E) is less than 0.001% by weight, the effect by the nitrogen-containing basic compound (E) is not obtained. On the other hand, when it exceeds 10% by weight, the sensitivity is liable to be lowered, or the development properties in unexposed areas are liable to become worse. 0370 <Fluorine-Based and/or Silicon-Based Surfactant (Component (F))>0371 It is preferred that the positive-working photosensitive resin composition according to the present invention contains any one of fluorine-based and/or silicon-based surfactants (such as fluorine-based surfactants, silicon-based surfactants, and surfactants containing both a fluorine atom and a silicon atom), or two or more thereof. 0372 When the positive-working photosensitive composition according to the present invention contains the. surfactant (F) it is possible to give a resist pattern having good sensitivity and resolution and good adhesiveness, which is less in development defect, during using an exposure light source of 250 nm or less, especially 220 nm or less. 0373 As the surfactant (F) can be enumerated the surfactants disclosed in JP-A-62-36663, JP-A-61-226746, JP-A-61-226745, JP-A-62-170950, JP-A-63-34540, JP-A-7-230165, JP-A-8-62834, JP-A-9-54432, JP-A-9-5988, and U.S. Pat. Nos. 5,405,720, 5,360,692, 5,529,881, 5,296,330, 5,436,098, 5,576,143, 5,294,511 and 5,824,451. Further, the following commercially available surfactants can also be used as they stand. 0374 Examples of the commercially available surfactants that can be used include fluorine-based surfactants or silicon-based surfactants, such as Eftop EF301 and EF303 (produced by Shin Akita Kasei Co., Ltd.), Fluorad FC430 and FC431 (produced by Sumitomo 3M Limited), Megafac F171, F173, F176, F189 and R08 (produced by Dainippon Ink and Chemicals, Inc.), Surflon S-382, SC101, SC102, SC103, SC104, SC105 and SC106 (produced by Asahi Glass Co., Ltd.), and Troy Sol S-366 (produced by Troy Chemical Co., Ltd.). Further, a polysiloxane polymer, KP-341 (produced by Shin-Etsu Chemical Co., Ltd.) can also be used as the silicon-based surfactant. 0375 An amount of the surfactant to be used is preferably from 0.0001 to 2% by weight, and more preferably from 0.001-to 1% by weight on a basis of the whole amount (excluding the solvent) of the positive-working photosensitive composition. 0376 <Alkali-Soluble Resin (Component (G))>0377 The positive-working photoresist composition according to the present invention can contain a resin (G) an acid-decomposable group-free resin that is insoluble in water and soluble in an alkaline developing solution. The addition of the resin (G) enhances the sensitivity. 0378 In the present invention, novolak resins having a molecular weight of from about 1,000 to 20,000 and polyhydroxystyrene derivatives having a molecular weight of from about 3,000 to 50,000 can be used as the resin (G). Since these resins have a large absorption to light of 250 nm or less, it is preferred to use them after partial hydrogenation or in an amount of 30% by weight or less of the whole amount of the resins. 0379 Further, resins containing a carboxyl group as the alkali-soluble group can be used. It is preferred that in order to enhance the resistance to dry etching, the carboxyl group-containing resin has a monocyclic or polycyclic alicyclic hydrocarbon group. Concretely, there can be enumerated copolymers of a methacrylic ester and (meth)acrylic acid having an alicyclic hydrocarbon structure that does not exhibit acid decomposability, and resins of a (meth)acrylic ester of an alicyclic hydrocarbon group having a terminal carboxyl group. 0380 <Other Substances>0381 If desired, the positive-working photosensitive composition according to the present invention can further contain a dye, a plasticizer, other surfactant than the component (F), a photosensitizer, and a compound to promote the dissolution in the developing solution. 0382 A dissolution promoting compound to the developing solution, which can be used in the present invention, is a low-molecular weight compound having two or more phenolic OH groups or one or more carboxyl groups and having a molecular weight of 1,000 or less. In the case where the compound has a carboxyl group, the compound is preferably an alicyclic or aliphatic compound for the same reason as described above. 0383 An amount of the dissolution promoting compound to be added is preferably from 2 to 50% by weight, and more preferably from 5 to 30% by weight to the resin (B) that is decomposed by the action of an acid to increase its solubility in the alkaline developing solution. When the addition amount of the dissolution promoting compound exceeds 50% by weight, the development residue becomes worse, and there is generated a new defect that the pattern deforms during the development. Thus, such is not preferred. 0384 Such a phenol compound having a molecular weight of 1,000 or less can be readily synthesized by those skilled in the art while referring to the methods disclosed in, for example, JP-A-4-122938, JP-A-2-28531, U.S. Pat. No. 4,916,210, and European Patent No. 219,294. 0385 Specific examples of the carboxyl group-containing alicyclic or aliphatic compound include carboxylic acid derivatives having a steroid structure (such as cholic acid, deoxycholic acid, and lithocholic acid), adamantane carboxylic acid derivatives, adamantane dicarbxoylic acid, cylclohexane carboxylic acid, and cyclohexane dicarboxylic acid. However, it should not be construed that the present invention is limited thereto. 0386 In the present invention, other surfactant than the fluorine-based and/or silicon-based surfactant (F) can be added. Concretely, examples include nonionic surfactants such as polyoxyethylene alkyl ethers (such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether), polyoxyethylene alkylaryl ethers (such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether), polyoxyethylene/polyoxypropylene block copolymers, sorbitan fatty acid esters (such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan triolate, and sorbitan tristearate), and polyoxyethylene sorbitan fatty acid esters (such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan triolate, and polyoxyethylene sorbitan tristearate). 0387 These surfactants may be used singly or in admixture of two or more thereof. 0388 <Using Method>0389 The photosensitive composition according to the present invention is a mixture of the foregoing components dissolved in a predetermined solvent and is applied on a predetermined support. As the solvent to be used are preferable ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, -butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, methylpyruvate, ethyl pyruvate, propyl pyruvate, N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, and tetrahydrofuran. These solvents may be used singly or in admixture. 0390 Of these are more preferable cyclohexanone, 2-heptanone, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, ethyl lactate, and ethyl ethoxypropionate. These solvents are used singly or as a mixture of two in a weight ratio of from 1/9 to 9/1. 0391 The positive-working photosensitive composition dissolved in a solvent is applied on a predetermined support in the following manner. 0392 That is, the foregoing photosensitive composition is applied on a substrate such as ones used for the production of precision integrated circuit elements (e.g., silicon/silicon dioxide coating films) by a proper coating method using, a spinner, a coater, etc. 0393 After the application, the photosensitive composition is exposed with light through a predetermined mask, baked, and then developed. Thus, there can be obtained a good resist pattern. The exposure light as referred to herein means far ultraviolet rays preferably having a wavelength of 250 nm or less, and more preferably 220 m or less. Specific examples include KrF excimer laser beams (248 nm), ArF excimer laser beams (193 nm), F2 excimer laser beams (157 nm), X rays, and electron beams. 0394 As the developing solution to be used in the development step can be used alkaline aqueous solutions such as inorganic alkalis (such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and ammonia water), primary amines (such as ethylamine and n-propylamide), secondary amines (such as diethylamine and di-n-butylamine), tertiary amines (such as triethylamine and methyldiethylamine), alcoholamines (such as dimethylethanolamine and triethanolamine), quaternary ammonium salts (such as tetramethylammonium hydroxide and tetraethylammonium hydroxide), and cyclic amines (such as pyrrole and piperidine). 0395 In addition, proper amounts of alcohols and surfactants may be added to the alkaline aqueous solution.

EXAMPLES 0396 The present invention will be specifically described below with reference to the Examples, but it should not be construed that the present invention is limited thereto. 0397 Synthesis of Resin (1): 0398 In a reaction vessel were charged acetoxyethyl vinyl ether, maleic anhydride, and t-butyl norbornenecarboxylate in a molar ratio of 10/50/40, and the mixture was dissolved in tetrahydrofuran to prepare a solution having a solids content of 40%. This solution was heated at 65 C. under a nitrogen stream. When the reaction temperature became stable, 1 mole % of a radical initiator, V-601 (produced by Wako Pure Chemical Industries, Ltd.) was added to the mixture to start the reaction. Fourteen hours after the heating, the reaction mixture was diluted two times with tetrahydrofuran and added to a hexane/ethyl acetate (9/1) mixed solvent in an amount of 10 times by volume the reaction mixture, to deposit a white powder. The deposited powder was collected by filtration and dissolved in tetrahydrofuran, followed by re-precipitation in a hexane/ethyl acetate (9/1) mixed solvent in an amount of 10 times by volume. A deposited white powder was collected by filtration and dried to obtain the desired resin (1). 0399 The obtained resin (1) was subjected to molecular weight analysis by GPC and found to have a weight average molecular weight of 9,200 in terms of a conversion value to polystyrene. Further, the NMR spectral analysis revealed that the resin (1) had a composition of acetoxyethyl vinyl ether/maleic anhydride/t-butyl norbornenecarboxylate of 12/51/37 in terms of a molar ratio. 0400 Resins (2) to (12) as shown in Table 1 were synthesized in the same manner as in the synthesis of the resin (1). In Table I-1, the repeating unit is in the order from the left side of the structural formula. 1TABLE I-1FourthThird repeatingrepeating unitVinylMaleicunit from thefrom the leftResinetheranhydrideleft sidesideMw213493357,800310503737,1004124632108,30051135411310,90061642429,7007133534129,30089374688,8009153619307,600101640341010,200111131421610,800121432441010,900

0401 The structures of the resins (1) to (12) are shown below. 123

124

125

Examples I-1 to I-12 and Comparative Examples I-1 and I-2 0402 <Preparation of Resist>0403 (Preparation and Evaluation Of Positive-Working Resist Composition) 0404 Each resin (2 g) as shown in Table I-2, which was synthesized in the foregoing synthesis example, a photo acid generator (in an amount as shown in Table I-2), an organic basic compound (4 mg), and optionally, a surfactant (5 mg) were compounded and dissolved in a solvent as shown in Table I-2 such that the solids content became 12% by weight. Thereafter, the solution was filtered by a 0.1 m micro-filter to prepare positive-working resist compositions of Examples I-1 to I-12 and Comparative Examples I-1 and I-2. Incidentally, in Table I-2, when plural solvents were used, the ratio means a weight ratio. 2TABLE I-2BasicSolventPhoto acidcom-Surfac-(weightResingenerator (mg)poundtantratio)Example(1) 2 gA2I-1/PAG4036 E3W3A2I-120/30Example(2) 2 gA2II-8/PAG4-39 E3W4A2I-225/32Example(3) 2 gA2I-8/PAC4-6 E3W5A2I-35/45Example(4) 2 gA2I-54/PAG4-48 E3W5A2I-48/43Example(5) 2 gA2II-12/PAC4-52 E3W5A1I-525/30Example(6) 2 gA2I-13/PAG4-50 E4W1A1I-630/28Example(7) 2 gA2II-20/PAC4-48 E5W2A1I-720/33Example(8) 2 gA2I-18/PAC4-41 E6W5A1I-835/23Example(9) 2 gA2II-10/PAG4-45 E1W5AlI-910/37Example(10) 2 gA2I-23/PAG4-48 E2W5A2/A4 I-1023/3480/20Example(11) 2 gA2I-50/PAG4-52 E4W5A1/A3 I-116/4592/8Example(12) 2 gA2I-49/PAG4-39 E5W5A2/A3/I-125/42A4 80/3/17Com-(1) 2 gPAC4-5 20E7A1parativeExampleI-1Com-R1 2 gPAC4-36 20E8A1parativeExampleI-2

0405 (Explanation of Table I-2) 0406 The resin R1 is a resin having the following repeating unit, as prepared according to Synthesis Example 6 (Sample No. 2) of JP-A-2001-200016. 126

0407 The symbols regarding the surfactant have the following meanings. 0408 W1: Megafac F176 (produced by Dainippon Ink and Chemicals, Inc.) (fluorine-based) 0409 W2: Megafac R08 (produced by Dainippon Ink and Chemicals, Inc.) (fluorine-based and silicon-based) 0410 W3: Polysiloxane polymer, KP-341 (produced by Shin-Etsu Chemical Co., Ltd.) 0411 W4: Polyoxyethylene nonylphenyl ether 0412 W5: Troy Sol S-366 (produced by Troy Chemical Industries, Inc.) 0413 The symbols regarding the basic compound have the following meanings. 0414 E1: 1,5-Diazabicyclo4.3.0-5-nonene (DBN) 0415 E2: Bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate 0416 E3: Trioctylamine 0417 E4: Triphenyl imidazole 0418 E5: Antipyrine 0419 E6: 2,6-Diisopropylaniline 0420 E7: Triisobutylamine 0421 E8: Triisodecylamine 0422 The symbols regarding the solvent have the following meanings. 0423 A1: Propylene glycol methyl ether acetate 0424 A2: 2-Heptanone 0425 A3: -Butyrolatone 0426 A4: Butyl acetate 0427 (Evaluation Test) 0428 Line Edge Roughness0429 First of all, ARC-29 (produced by Brewer Science Limited) was applied in a thickness of 85 nm on a silicon wafer utilizing a spin coater and then dried. The obtained positive-working photoresist composition was applied on the silicon wafer and baked at 130 C. for 90 seconds to form a coating film having a film thickness of 0.30 m. 0430 The thus obtained wafer was exposed using an ArF excimer laser stepper (ArF Exposure Unit 9300, produced by ISI) having a resolution mask installed therein, while changing the exposure amount. Thereafter, the wafer was heated in a clean room at 130 C. for 90 seconds, developed with a tetramethylammonium hydroxide developing solution (2.38% by weight) for 60 seconds, rinsed with distilled water, and then dried to obtain a pattern. 0431 With respect to a range of an edge of 5 m in the longitudinal direction of a line pattern of 125 nm obtained from a minimum exposure amount necessary for reproducing a line pattern of 125 nm (line/space1/1) in the mask, a distance from the standard line at which the edge should be present was measured at 50 points using S9220 (produced by Hitachi, Ltd.), to determine a standard deviation, from which was calculated a 3 value. The smaller the 3 value, the better the performance is. 0432 Development Defect A0433 First of all, ARC-29 (produced by Brewer Science Limited) was applied in a thickness of 85 nm on a silicon wafer utilizing a spin coater and then dried. The obtained positive-working photoresist composition was applied on the silicon wafer and baked at 130 C. for 90 seconds to form a coating film having a film thickness of 0.30 m. 0434 Next, the thus obtained wafer was exposed using an ArF excimer laser stepper (ArF Exposure Unit 9300, produced by ISI) through a test mask of a 20 m contact hole pattern (hole duty ratio1:3) and heated at 130 C. for 90 seconds. Subsequently, the wafer was subjected to paddle development with 2.38% by weight TMAH (tetramethylammonium hydroxide aqueous solution) for 60 seconds, rinsed with pure water for 30 seconds, and then spin dried. The obtained sample was measured for the number of development defects by KLA-2112 (produced by KLA-Tencor Corporation), and the obtained primary data value was made the number of development defects. 0435 Development Defect B0436 First of all, ARC-29 (produced by Brewer Science Limited) was applied in a thickness of 85 nm on a silicon wafer utilizing a spin coater and then dried. The obtained positive-working photoresist composition was applied on the silicon wafer and baked at 130 C. for 90 seconds to form a coating film having a film thickness of 0.30 m. 0437 The thus obtained wafer was exposed with ArF excimer laser beams (wavelength: 193 nm, an ArF stepper produced by ISI) and heated at 130 C. for 90 seconds. Subsequently, the wafer was developed with a 2.38% by weight tetramethylammonium hydroxide aqueous solution and rinsed with distilled water to form a 0.20 m contact hole pattern (pitch: 1/3). The obtained resist pattern was measured for the number of development defects by KLA-2112 (produced by KLA-Tencor Corporation), and the obtained primary data value was made the number of development defects. On the basis of the data, the defects were observed by SEM, and the number of defects which will become extreme obstacles in the formation of the contact hole (defects clogging the holes: killer defects) was counted. 3TABLE 1-3Line edgeDevelopmentDevelopmentroughnessdefect Adefect B(nm)(number)(number)Example7420I-1Example7510I-2Example8922I-3Example8741I-4Example6320I-5Example6300I-6Example6310I-7Example6290I-8Example7691I-9Example6280I-10Example71043I-11Example7892I-12Compara-17122023tiveExampleI-1Compara-18136032tiveExampleI-2

0438 It can be understood from the results shown in Table 1-3 that the compositions according to the present invention are superior in various characteristics. 0439 The present invention can provide a positive-working photosensitive composition having improved line edge roughness and development defect. Accordingly, the positive-working photosensitive composition according to the present invention is suitably used for micro photo-fabrication using far ultraviolet rays, especially ArF excimer laser beams.

Examples II-1 to II-12 and Comparative Examples II-1 and II-2 0440 <Preparation of Resist>0441 (Preparation and Evaluation of Positive-Working Resist Composition) 0442 Each resin (in an amount as shown in Table II-2) as shown in Table II-2, which was synthesized in the foregoing synthesis example, a photo acid generator (in an amount as shown in Table II-2), an organic basic compound (4 mg), and optionally, a surfactant (5 mg) were compounded and dissolved in a solvent as shown in Table II-2 such that the solids content became 12% by weight. Thereafter, the solution was filtered by a 0.1 m micro-filter to prepare positive-working resist compositions of Examples II-1 to II-12 and Comparative Examples II-1 and II-2. Incidentally, in Table II-2, when plural solvents were used, the ratio means a weight ratio. 4TABLE II-2Photo acidBasicOthergeneratorcom-Surfac-addi-Resin(mg)poundtanttiveSolventExample(1)A1I-7 45E3W5A1II-12 gExample(2)A1I-26/E3W2C1A2II-21.7 gPAG4-39 330 mg11/39Example(3)A1VIII-3/E4W3C3A1II-31.7 gPAG4-6 8/40300 mgExample(4)A1I-9 43E5W5A2II-42 gExample(5)A1II-5/E1W5A1/II-52 gPAG4-41 A3 13/329/1Example(6)A1I-14/E2W1A1/II-62 gPAG4-52 A4 12/4095/5Example(7)A1I-22/E6W2A1II-72 gPAG4-48 9/36Example(8)A1I-8/E5W1A1/II-82 gPAG4-52/A5 PAG-7-3 80/2010/32/4Example(9)A1I-17 44E3W4C2A1II-91.7 g300 mgExample(10)A1III-1/E3W5A2II-102 gPAG4-52/A2I-65 4/36/10Example(11)A1I-25/E3W5A1II-112 gPAG4-45 12/36Example(12)A1I-20/E3W5A1II-122 gPAG4-48 10/32Compara-R1PAG4-5 20E7A1tive2 gExampleII-1Compara-(1)PAG4-36 20E8A1tive2 gExampleII-2

0443 (Explanation of Table II-2) 0444 The resin R1 is a resin having the following repeating unit, as prepared according to Synthesis Example 6 (Sample No. 2) of JP-A-2001-200016. 127

0445 The symbols regarding the surfactant have the following meanings. 0446 W1: Megafac F176 (produced by Dainippon Ink and Chemicals, Inc.) (fluorine-based) 0447 W2: Megafac R08 (produced by Dainippon Ink and Chemicals, Inc.) (fluorine-based and silicon-based) 0448 W3: Polysiloxane polymer, KP-341 (produced by Shin-Etsu Chemical Co., Ltd.) 0449 W4: Polyoxyethylene nonylphenyl ether 0450 W5: Troy Sol S-366 (produced by Troy Chemical Industries, Inc.) 0451 The symbols regarding the basic compound have the following meanings. 0452 E1: 1,5-Diazabicyclo4.3.0-5-nonene (DBN) 0453 E2: Bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate 0454 E3: Trioctylamine 0455 E4: Triphenyl imidazole 0456 E5: Antipyrine 0457 E6: 2,6-Diisopropylaniline 0458 E7: Triisobutylamine 0459 E8: Triisodecylamine 0460 The symbols regarding the solvent have the following meanings. 0461 A1: Propylene glycol methyl ether acetate 0462 A2: 2-Heptanone 0463 A3: Ethylethoxy propionate 0464 A4: -Butyrolatone 0465 A5: Butyl acetate 0466 The symbols regarding other additive have the following meanings. 0467 C1: t-Butyl lithocholate 0468 C2: t-Butyl cholate 0469 C3: t-Butyl hydroxyadamantanecarboxylate 0470 (Evaluation Test) 0471 Pitch Dependency(i.e., Defocus Latitude Depended on Line Pitch)0472 First of all, ARC-29 (produced by Brewer Science Limited) was applied in a thickness of 85 nm on a silicon wafer utilizing a spin coater and then dried. The obtained positive-working photoresist composition was applied on the silicon wafer and dried at 130 C. for 90 seconds to prepare a positive-working photoresist film having a film thickness of 300 nm. The thus obtained wafer was exposed with ArF excimer laser beams (wavelength: 193 nm, NA0.6, an ArF stepper produced by ISI) and then heated at 130 C. for 90 seconds. Subsequently, the wafer was developed with a 2.38% by weight tetramethylammonium hydroxide aqueous solution and rinsed with distilled water to obtain a resist pattern profile. 0473 The obtained resist pattern was observed by a scanning electron microscope to obtain the following evaluation. 0474 At the same exposure amount as the exposure amount necessary for reproducing a mask pattern of 0.125 m (line/space 1/1), a coefficient of fluctuation from 0.125 m (0.125L1)100/0.125 (%) wherein L1 (side chain) represents a line width of a 0.125 m isolated pattern was made an index of pitch dependency. The smaller the value, the smaller the pitch dependency is, that is, the pitch dependency becomes better. 0475 Evaluation Method of Resistance to Side Lobe Light by Halftone Mask Exposure0476 ARC-29 (produced by Brewer Science Limited) was applied in a thickness of 85 nm on a silicon wafer utilizing a spin coater and then dried. The obtained positive-working photoresist composition was applied on the silicon wafer and dried at 130 C. for 90 seconds to prepare a positive-working photoresist film having a film thickness of 300 nm. Next, the thus obtained wafer was exposed by an ArF stepper (produced by ISI) through a halftone mask (transmission: 80%) of a 0.165 m contact hole pattern (hole duty ratio1:3) and then heated at 130 C. for 60 seconds. Subsequently, the wafer was subjected to paddle development with 2.38% by weight TMAH for 60 seconds, rinsed with pure water for 30 seconds, and then spin dried to obtain an image. During this operation, a ratio of Elimit/Eopt wherein Eopt represents an optimum exposure amount necessary for reproducing an isolated contact hole (mask) having a diameter of 0.165 m to 0.140 m, and Elimit represents a minimum exposure amount necessary for transferring the side lobe light onto the resist substrate was made an index of resistance to side lobe light. The value of Comparative Example II-1 was standardized to be 1, and the resistance to side lobe light of each of Examples II-1 to II-12 and Comparative Example II-2 was relatively evaluated. As the value increases, the resistance to side lobe light is superior, whereas as the value decreases, the resistance to side lobe light is inferior. 5TABLE II-3Pitch dependency (%)Side lobe marginExample II-1321.9Example II-2331.9Example II-3341.8Example II-4332.1Example II-5281.9Example II-6261.9Example II-7291.8Example II-8301.9Example II-9452.0Example II-10302.1Example II-11281.9Example II-12271.9Comparative901.0Example II-1Comparative731.2Example II-2

0477 It can be understood from the results shown in Table II-3 that the compositions according to the present invention are superior in various characteristics. 0478 The present invention can provide a positive-working photosensitive composition that is small in pitch dependency and has an improved broad side lobe margin. Accordingly, the positive-working photosensitive composition according to the present invention is suitably used for micro photo-fabrication using far ultraviolet rays, especially ArF excimer laser beams.

Examples III-1 to III-12 and Comparative Examples III-1 and III-2 0479 <Preparation of Resist>0480 (Preparation and Evaluation of Positive-Working Resist Composition) 0481 Each resin (2 g) as shown in Table III-2, which was synthesized in the foregoing synthesis example, a photo acid generator (in an amount as shown in Table III-2), an organic basic compound (4 mg), and optionally, a surfactant (5 mg) were compounded and dissolved in a solvent as shown in Table III-2 such that the solids content became 12% by weight. Thereafter, the solution was filtered by a 0.1 m micro-filter to prepare positive-working resist compositions of Examples III-1 to III-12 and Comparative Examples III-1 and III-2. Incidentally, in Table III-2, when plural solvents were used, the ratio means a weight ratio. 6TABLE III-2BasicPhoto acidcom-Surfac-ResingeneratorpoundtantSolventExample(1)SI-8 42 mgE7W5S1/S5 8/2III-1Example(2)SI-33/A2I-65 E2W3S1/S6 8/2III-220 mg/50 mgExample(3)SI-11 50 mgE1W4S1/S5 7/3III-3Example(4)SI-9 50 mgE3W1S1/S7 85/15III-4Example(5)SI-35/A2I-13 E4W2S1/58 9/1III-522 mg/49 mgExample(6)SI-9/A2I1-9 E5W5S1/S2 85/15III-626 mg/56 mgExample(7)SI-33 41 mgE6W5S1/S6/S9 III-770/25/5Example(8)SI-4 45 mgE8W5S1/S6/S7 III-B68/26/6Example(9)SI-35 43 mgE2W5S1/S4/S6 8/1/1III-9Example(10)SI-9/A2II-11 E2W5S1/S4/S7 5/4/1III-1030 mg/36 mgExample(11)SI-35/A2I-13 E2W5S1/S3/S8 7/2/1III-1130 mg/22 mgExample(12)SI-32 42 mgE2/E5 W5S1/S5/S7 III-121/180/15/5Compara-(1)PAG1 40 mgE7NilS1tiveExampleIII-1Compara-R1PAG2 40 mgE8NilS1tiveExampleIII-2

0482 (Explanation of Table III-2) 0483 The resin R1 is a resin having the following repeating unit, as prepared according to Synthesis Example 6 (Sample No. 2) of JP-A-2001-200016. 128

0484 The photo acid generators are those illustrated previously. However, PAG1 and PAG2 used in Comparative Examples III-1 and III-2 are as follows. 129

0485 The symbols regarding the surfactant have the following meanings. 0486 W1: Megafac F176 (produced by Dainippon Ink and Chemicals, Inc.) (fluorine-based) 0487 W2: Megafac R08 (produced by Dainippon Ink and Chemicals, Inc.) (fluorine-based and silicon-based) 0488 W3: Polysiloxane polymer, KP-341 (produced by Shin-Etsu Chemical Co., Ltd.) 0489 W4: Polyoxyethylene nonylphenyl ether 0490 W5: Troy Sol S-366 (produced by Troy Chemical Industries, Inc.) 0491 The symbols regarding the basic compound have the following meanings. 0492 E1: 1,5-Diazabicyclo4.3.0-5-nonene (DBN) 0493 E2: N,N-Bis(2-hydroxyethyl)aniline 0494 E3: Trioctylamine 0495 E4: Triphenyl imidazole 0496 E5: Antipyrine 0497 E6: 2,6-Diisopropylaniline 0498 E7: Triisobutylamine 0499 E8: Triisodecylamine 0500 The symbols regarding the solvent have the following meanings. 0501 S1: Propylene glycol methyl ether acetate 0502 S2: Ethyl lactate 0503 S3: Butyl acetate 0504 S4: 2-Heptanone 0505 S5: Propylene glycol monomethyl ether 0506 S6: Ethyl ethoxypropionate 0507 S7: -Butyrolatone 0508 S8: Ethylene carbonate 0509 S9: Propylene carbonate 0510 (Evaluation Test) 0511 Development Defect0512 First of all, ARC-29 (produced by Brewer Science Limited) was applied in a thickness of 85 nm as an antireflection film on a silicon wafer utilizing a spin coater and then dried. The obtained positive-working photoresist composition was applied on the silicon wafer and baked at 130 C. for 90 seconds to form a coating film having a film thickness of 0.40 m. 0513 Next, the thus obtained wafer was exposed using an ArF excimer laser stepper (ArF Exposure Unit 9300, produced by ISI) through a test mask of a 20 m contact hole pattern (hole duty ratio1:3) and heated at 130 C. for 90 seconds. Subsequently, the wafer was subjected to paddle development with 2.38% by weight TMAH (tetramethylammonium hydroxide aqueous solution) for 45 seconds, rinsed with pure water for 20 seconds, and then spin dried. The number of development defects remaining on the antireflection film of the thus obtained sample was measured by KLA-2112 (produced by KLA-Tencor Corporation), and the obtained primary data value was made the number of development defects. 0514 Resistance to Side Lobe Light0515 ARC-29 (produced by Brewer Science Limited) was applied in a thickness of 85 nm as an antireflection film on a Bare Si substrate utilizing a spin coater. Thereafter, each resist film was applied in a film thickness of 0.40 m and dried at 130 C. for 60 seconds by a vacuum adsorption type hot plate. Next, the resist film was exposed by an ArF stepper (produced by ISI) through a halftone mask (transmission: 80%) of a 0.180 m contact hole pattern (hole duty ratio1:3) and then heated at 130 C. for 60 seconds. Subsequently, the resist film was subjected to paddle development with 2.38% by weight TMAH for 60 seconds, rinsed with pure water for 30 seconds, and then spin dried to obtain an image. During this operation, a ratio of Elimit/Eopt wherein Eopt represents an optimum exposure amount necessary for reproducing an isolated contact hole (mask) having a diameter of 0.18 m to 0.14 m, and Elimit represents a minimum exposure amount necessary for transferring the side lobe light onto the resist substrate was made an index of resistance to side lobe light. The value of Comparative Example III-1 was standardized to be 1, and the resistance to side lobe light of each of Examples III-1 to III-12 and Comparative Example III-2 was relatively evaluated. As the value increases, the resistance to side lobe light is superior, whereas as the value decreases, the resistance to side lobe light is inferior. 0516 Profile0517 ARC-29 (produced by Brewer Science Limited) was applied in a thickness of 85 nm as an antireflection film on a Bare Si substrate utilizing a spin coater. Thereafter, each resist film was applied in a film thickness of 0.30 m and dried at 130 C. for 60 seconds by a vacuum adsorption type hot plate. Next, the resist film was exposed by an ArF stepper (produced by ISI) through a mask of 0.130 m line-and-space (line/space1/10) and then heated at 130 C. for 60 seconds. Subsequently, the resist film was subjected to paddle development with 2.38% by weight TMAH for 60 seconds, rinsed with pure water for 30 seconds, and then spin dried to obtain an image. A cross-section of the obtained pattern was observed and evaluated by an scanning electron microscope (SEM). 0518 Pattern Collapse0519 ARC-29 (produced by Brewer Science Limited) was applied in a thickness of 85 nm as an antireflection film on a Bare Si substrate utilizing a spin coater. Thereafter, each resist film was applied in a film thickness of 0.30 m and dried at 130 C. for 60 seconds by a vacuum adsorption type hot plate. Next, the resist film was exposed by an ArF stepper (produced by ISI) through a mask of 0.130 m line-and-space (line/space1/10) and then heated at 130 C. for 60 seconds. Subsequently, the resist film was subjected to paddle development with 2.38% by weight TMAH for 60 seconds, rinsed with pure water for 30 seconds, and then spin dried to obtain an image. A maximum line width at which pattern collapse was generated during the overexposure was made an index of pattern collapse. 0520 The results obtained are shown in Table III-3. 7TABLE III-3PatternDevelopmentSide lobecollapsedefectmarginProfile(nm)Example351.21Rectangle90III-1Example331.20Rectangle90III-2Example481.19Rectangle95III-3Example361.20Rectangle90III-4Example321.21Rectangle90III-5Example341.21Rectangle90III-6Example281.24Rectangle85III-7Example281.25Rectangle85III-8Example321.21Rectangle90III-9Example311.20Rectangle90III-10Example271.25Rectangle85III-11Example261.25Rectangle85III-12Comparative2801.06Film120ExamplethicknessIII-1reductionComparative4701.03Film122.5ExamplethicknessIII-2reduction

0521 It can be understood from the results shown in Table III-3 that the compositions according to the present invention are superior in various characteristics. 0522 The present invention can provide a positive-working photosensitive composition that is remarkably improved in development defect and resistance to side lobe light and a positive-working photosensitive composition that can form a good profile without causing pattern collapse. Accordingly, the positive-working photosensitive composition according to the present invention is suitably used for micro photo-fabrication using far ultraviolet rays, especially ArF excimer laser beams. 0523 The entitle disclosure of each and every foreign patent application from which the benefit of foreign priority has been claimed in the present application is incorporated herein by reference, as if fully set forth herein. 0524 While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.