228 allows for a sharper angle to be formed compared to existing J-shaped rods. This may allow for a more compact rod assembly 220 compared to existing solutions.

In an embodiment, the second electrical path 226 may be surrounded by an electrically insulating first liner 231, such as a polymeric material. In an embodiment, the first liner 231 may be applied over the second electrical path 226 with a powder based overmolding process. For example, a powder is applied over the second electrical path 226 (i.e., the segments 226_A-Cand the conductive bridge 228), and the powder is converted into a polymeric coating through the application of a high temperature and a high pressure. Such an overmolding process allows for excellent contact between the first liner 231 and the second electrical path 226. As such, air gaps are avoided and capacitance is reduced. In some embodiments, the first liner 231 may comprise polytetrafluoroethylene (PTFE).

In an embodiment, the first electrical path 239 is provided over the first liner 231. In an embodiment, the first electrical path 239 may comprise an electrically conductive shell that surrounds the second electrical path 226 and the first liner 231. The first electrical path 239 may be used to deliver an RF bias to the chuck (not shown in FIG. 2A). In an embodiment, the first electrical path 239 is shown as a monolithic shell. However, it is to be appreciated that the first electrical path 239 may also be modular, as will be described in greater detail below with respect to FIG. 2B. The first electrical path 239 and the second electrical path 226 may comprise electrically conductive material, such as copper or the like. In an embodiment, a second liner 232 is provided over an outer surface of the first electrical path 239. The second liner 232 may also be formed with an overmolding process, similar to the first liner 231.

In an embodiment, a housing 225 may be provided around the first electrical path 239. The housing 225 may also be an electrically conductive material. For example, the housing 225 may comprise aluminum in some embodiments. In an embodiment, the housing 225 may be configured to be held at a ground potential. As shown, an air gap 235 is provided between the second liner 232 and the housing 225. The addition of the air gap 235 further reduces capacitance in some embodiments.

The overall structure of the rod assembly 220 enables significantly improved capacitance performance compared to existing solutions. That is, a capacitance between the first electrical path 239 and the housing 225 is significantly reduced. This allows for improved electrical efficiency (e.g., reduced leakage to ground). Additionally, the electrical insulation between conductive layers (e.g., the second electrical path 226, the first electrical path 239, and the housing 225) allows for improved resistance to arcing and/or the like. As such, higher voltages can be supplied along the rod assembly 220. For example, voltages up to approximately 10 kV can be supplied along the rod assembly 220.

Referring now to FIG. 2B, a cross-sectional illustration of the corner region 223 of the rod assembly 220 is shown, in accordance with an embodiment. As shown, the bridge 228 may be overmolded with a third liner 241. The third liner 241 may be coupled to the first liner 231 with a fusing process or the like. Accordingly, while shown as distinct components in FIG. 2B, it is to be appreciated that the first liner 231 and the third liner 241 may appear as a monolithic part that surrounds the second segment 226_B, the bridge 228, and the third segment 226_C. However, the fusing process between the first liner 231 and the third liner 241 allows for easier manufacture and assembly of the rod assembly 220.

Additionally, the first electrical path 239 may include an electrically conductive coupler 242 at the corner region 223. The use of such a coupler 242 allows for a modular construction that enables the first electrical path 239 to have linear tubes. As such, the tube for the first electrical path 239 does not need to be bent into shape, as is the case in existing RF rod solutions. In an embodiment, the coupler 242 and other portions of the corner region 223 may be embedded within an insulating corner reinforcement 248. The insulated corner reinforcement may be formed from a plurality of individual parts that are fitted together, as will be described in greater detail below. As shown, the insulating corner reinforcement 248 may directly contact a portion of the housing 225. As such, the air gap 235 may not be continuous along an interior surface of the housing 225 in some embodiments.

Referring now to FIG. 3A, a cross-sectional illustration of a portion of rod assembly 320 is shown, in accordance with an embodiment. In FIG. 3A, a corner region of the first electrical path 339 is shown in isolation in order to more clearly illustrate an interface between the first electrical path 339_A-Band the coupler 342. In an embodiment, the horizontal portion of the first electrical path 339_Aand the vertical portion of the first electrical path 339 may comprise external notches 361, and the coupler 342 may comprise protrusions 362 that fit into the notches 361. In such an embodiment, the notches 361 and the protrusions 362 secure the horizontal and vertical portions of the first electrical path 339_A-Bto the coupler 342 in order to provide a secure connection that allows for improved electrical coupling between the components. In some embodiments, only the mechanical coupling of the notches 361 and the protrusions 362 are necessary to provide the desired electrical conductivity along the first electrical path 339. However, in other embodiments, a brazing, welding, or other fusion process may be used (alone or in combination with a mechanical coupling) in order to provide the desired electrical conductivity along the first electrical path 339. While a particular example of a notch 361 and protrusion 362 architecture is shown in FIG. 3A, it is to be appreciated that any suitable mechanical coupling may be used between the horizontal and vertical portions of the first electrical path 339_A-Band the coupler 342.

Referring now to FIG. 3B, a cross-sectional illustration of a portion of a rod assembly 320 is shown, in accordance with an additional embodiment. In FIG. 3B, the outer housing 325 and the insulating corner reinforcement 348 are shown in greater detail. As shown, the insulating corner reinforcement 348 may comprise a plurality of discrete components 348_Aand 348_B. In such an embodiment, the multiple components may be press fit together in order to surround the corner region of the interior first electrical path and second electrical path (both omitted for simplicity). For example, a mechanical coupling region