Cryogenically cooled rotatable electrostatic chuck

Abstract

Embodiments of the present disclosure relate to a rotatable electrostatic chuck. In some embodiments, the rotatable electrostatic chuck includes a dielectric disk having at least one chucking electrode and a plurality of coolant channels; a cryogenic manifold coupled to the dielectric disk and having a coolant inlet and a coolant outlet, both of which are fluidly coupled to the plurality of coolant channels; a shaft assembly coupled to the cryogenic manifold; a cryogenic supply chamber coupled to the shaft assembly; a supply tube coupled to the cryogenic supply chamber and the coolant inlet to supply a cryogenic medium to the plurality of coolant channels, wherein the supply tube extends through a central opening of the shaft assembly; and a return tube coupled to the coolant outlet and the cryogenic supply chamber, wherein the supply tube is disposed within the return tube.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to electrostatic chucks for holding substrates during microelectronic device fabrication processes. Background Art

[0002] The formation of certain devices on a substrate requires multiple layers of thin films that are deposited in a deposition chamber such as a physical vapor deposition (PVD) chamber. In some embodiments, the substrate needs to be rotated during the deposition process to obtain good film uniformity. The deposition of certain layers may also require cooling the substrate. In addition, the deposition process requires high vacuum pressure. Electrostatic chucks are typically used to electrostatically hold a substrate on a substrate support during a deposition process. Conventionally, an electrostatic chuck includes a ceramic body having one or more electrodes therein. Typical rotatable electrostatic chucks can only be used at room temperature or higher. However, the inventors have observed that certain processes require cooling the substrate to a temperature significantly lower than that possible with current electrostatic chucks.

[0003] Accordingly, the inventors provide embodiments of improved rotatable electrostatic chucks. Summary of the invention

[0004] Embodiments of the present disclosure generally relate to a rotatable electrostatic chuck. In some embodiments, the electrostatic chuck includes a dielectric disk having a support surface for supporting a substrate and an opposing second surface, wherein at least one chucking electrode is disposed between the support surface and the second surface within the dielectric disk, and wherein a plurality of coolant channels are disposed within the dielectric disk; a cryogenic manifold coupled to the second surface of the dielectric disk and having a coolant inlet and a coolant outlet, wherein the coolant inlet and the coolant outlet are both fluidly coupled to the plurality of coolant channels; a shaft assembly coupled to the cryogenic manifold at a first end thereof, wherein the shaft assembly includes a central opening extending through the shaft assembly; and a cryogenic supply chamber disposed at a position of the shaft assembly relative to the first end thereof. a supply pipe coupled at a first end thereof to the cryogenic supply chamber to receive a cryogenic medium and coupled at a second end thereof to a coolant inlet to supply the cryogenic medium to a plurality of coolant channels, wherein the supply pipe extends through the central opening and is concentric with the shaft assembly; and a return pipe coupled at a first end thereof to the coolant outlet and coupled at a second end thereof to the cryogenic supply chamber to return the cryogenic medium to the cryogenic supply chamber after the cryogenic medium flows through the plurality of coolant channels, wherein the return pipe extends through the central opening and is concentric with the supply pipe, and wherein the supply pipe is disposed within the return pipe.

[0005] In some embodiments, an electrostatic chuck includes a dielectric disk having a support surface for supporting a substrate and an opposing second surface, wherein at least one clamping electrode is disposed between the support surface and the second surface within the dielectric disk, and wherein a plurality of coolant channels are disposed within the dielectric disk; a cryogenic manifold coupled to the second surface of the dielectric disk and having a coolant inlet and a coolant outlet, wherein both the coolant inlet and the coolant outlet are fluidly coupled to the plurality of coolant channels; a shaft assembly coupled to the cryogenic manifold at a first end thereof, wherein the shaft assembly includes a central opening extending through the shaft assembly; a cryogenic supply chamber coupled to the shaft assembly at a second end of the shaft assembly opposite the first end; a vacuum pump fluidly coupled to the cryogenic supply chamber to maintain the cryogenic supply chamber at a vacuum pressure; and a supply tube, the supply tube A supply pipe is coupled to the cryogenic supply chamber at a first end thereof to receive a cryogenic medium, and is coupled to a coolant inlet at a second end of the supply pipe to supply the cryogenic medium to a plurality of coolant channels, wherein the supply pipe extends through the central opening and is concentric with the shaft assembly; an insulation layer disposed on an outer surface of the supply pipe; a return pipe, which is coupled to the coolant outlet at a first end thereof and is coupled to the cryogenic supply chamber at a second end thereof to return the cryogenic medium to the cryogenic supply chamber after the cryogenic medium flows through the plurality of coolant channels, wherein the return pipe extends through the central opening and is concentric with the supply pipe, and wherein the supply pipe is disposed within the return pipe; a slip ring, which is coupled to the second end of the shaft assembly to cause power from a power source to be coupled to at least one clamping electrode; and a drive assembly, which is coupled to the shaft assembly to rotate the shaft assembly and the dielectric disk.

[0006] In some embodiments, a processing chamber includes a chamber body having an interior volume; and an electrostatic chuck disposed within a lower portion of the interior volume. The electrostatic chuck includes a dielectric disk having a support surface for supporting a substrate and an opposing second surface, wherein at least one chucking electrode is disposed within the dielectric disk between the support surface and the second surface, and wherein a plurality of coolant channels are disposed within the dielectric disk; a cryogenic manifold coupled to the second surface of the dielectric disk and having a coolant inlet and a coolant outlet, the coolant inlet and the coolant outlet both being fluidly coupled to the plurality of coolant channels; a shaft assembly coupled to the cryogenic manifold at a first end thereof, wherein the shaft assembly includes a central opening extending through the shaft assembly; and a cryogenic supply chamber disposed within the shaft assembly relative to the first surface of the dielectric disk. a supply pipe coupled at a first end thereof to the cryogenic supply chamber to receive a cryogenic medium, and coupled at a second end of the supply pipe to a coolant inlet to supply the cryogenic medium to a plurality of coolant channels, wherein the supply pipe extends through the central opening and is concentric with the shaft assembly; and a return pipe coupled at a first end thereof to the coolant outlet, and coupled at a second end of the return pipe to the cryogenic supply chamber to return the cryogenic medium to the cryogenic supply chamber after the cryogenic medium flows through the plurality of coolant channels, wherein the return pipe extends through the central opening and is concentric with the supply pipe, and wherein the supply pipe is disposed within the return pipe.

[0007] Other and further embodiments of the present disclosure are described in more detail below. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The illustrative embodiments of the present disclosure, briefly summarized above and discussed in more detail below, can be understood by reference to the embodiments of the present disclosure depicted in the accompanying drawings. However, the accompanying drawings depict only typical embodiments of the present disclosure and are therefore not to be considered limiting of the scope of the invention, as the present disclosure may admit to other equally effective embodiments.

[0009] Figure 1 A schematic side view of a processing chamber suitable for having an electrostatic chuck is depicted in accordance with at least some embodiments of the present disclosure.

[0010] Figure 2A A schematic cross-sectional view of an upper portion of an electrostatic chuck is depicted in accordance with at least some embodiments of the present disclosure.

[0011] Figure 2B A schematic cross-sectional view of a lower portion of an electrostatic chuck is depicted in accordance with at least some embodiments of the present disclosure.

[0012] Figure 2C Depiction Figure 2B A close-up schematic cross-sectional view of a portion of an electrostatic chuck.

[0013] For ease of understanding, the same reference numerals are used as much as possible to designate common identical elements in the drawings. The drawings are not drawn to scale and may be simplified for clarity. Elements and features of one embodiment may be advantageously incorporated into other embodiments without further description. DETAILED DESCRIPTION

[0014] Embodiments of a rotatable electrostatic chuck (ESC) with cryogenic cooling are provided herein. The innovative electrostatic chuck provides a cryogenic cooling medium to a rotating ESC, thereby advantageously allowing the rotating ESC to be used in processes requiring lower temperatures than is possible with a conventional rotatable ESC using conventional cooling methods.

[0015] Figure 1 is a schematic cross-sectional view of a processing chamber (e.g., a plasma processing chamber) according to some embodiments of the present disclosure. In some embodiments, the plasma processing chamber is a physical vapor deposition (PVD) processing chamber. However, other types of processing chambers configured for different processes may also use or be modified for use in conjunction with embodiments of the innovative electrostatic chuck described herein.

[0016] The chamber 100 is a vacuum chamber that is suitably adapted to maintain a subatmospheric pressure within a chamber interior volume 120 during substrate processing. The chamber 100 includes a chamber body 106 covered by a lid 104 that surrounds a processing volume 119 located in an upper portion of the chamber interior volume 120. The chamber 100 may also include one or more shields 105 that surround various chamber components to prevent undesirable reactions between such components and ionized processing materials. The chamber body 106 and lid 104 may be made of a metal such as aluminum. The chamber body 106 may be grounded via a coupling to ground 115.

[0017] The substrate support 124 is disposed within the chamber interior volume 120 to support and hold a substrate S, such as a semiconductor wafer, or other such substrates that can be electrostatically held. The substrate support 124 may generally include an electrostatic chuck 150 (see below). FIG. 2A to FIG. 2B 1 and 12 ) and a hollow support shaft 112 for supporting the electrostatic chuck 150. The hollow support shaft 112 provides a conduit to provide the electrostatic chuck 150, for example, with process gases, fluids, coolants, power, or the like.

[0018] In some embodiments, the hollow support shaft 112 is coupled to a lifting mechanism 113, such as an actuator or a motor, which provides a lifting mechanism for the electrostatic chuck 150 to be moved in an upper processing position (eg, Figure 1The bellows assembly 110 is disposed about the hollow support shaft 112 and is coupled between the electrostatic chuck 150 and the bottom surface 126 of the chamber 100 to provide a resilient seal that allows vertical movement of the electrostatic chuck 150 while preventing loss of vacuum within the chamber 100. The bellows assembly 110 also includes a lower bellows flange 164 that contacts an O-ring 165 or other suitable sealing element that contacts the bottom surface 126 to help prevent loss of chamber vacuum.

[0019] The hollow support shaft 112 provides a conduit for coupling a fluid source 142, a gas source 141, a chucking power source 140, and an RF source (e.g., an RF plasma power source 170 and an RF bias power source 117) to the electrostatic chuck 150. In some embodiments, the RF plasma power source 170 and the RF bias power source 117 are coupled to the electrostatic chuck via corresponding RF matching networks (only the RF matching network 116 is shown). In some embodiments, the substrate support may alternatively include AC, DC, or RF bias power.

[0020] The substrate lifter 130 may include lift pins 109 mounted on a platform 108 coupled to a shaft 111 coupled to a second lift mechanism 132 for raising and lowering the substrate lifter 130 so that a substrate “S” may be placed on or removed from an electrostatic chuck 150. The electrostatic chuck 150 includes through holes for receiving the lift pins 109. A bellows assembly 131 is coupled between the substrate lifter 130 and the bottom surface 126 to provide a resilient seal that maintains the chamber vacuum during vertical movement of the substrate lifter 130.

[0021] The chamber 100 is coupled to and in fluid communication with a vacuum system 114, which includes a throttle valve (not shown) and a vacuum pump (not shown) for exhausting the chamber 100. The pressure within the chamber 100 can be adjusted by adjusting the throttle valve and / or the vacuum pump. The chamber 100 is also coupled to and in fluid communication with a process gas source 118, which can supply one or more process gases to the chamber 100 for processing a substrate disposed therein.

[0022] In operation, for example, a plasma 102 may be generated in the chamber interior volume 120 to perform one or more processes. The plasma 102 may be generated by coupling power from a plasma power source (e.g., an RF plasma power source 170) to a process gas via one or more electrodes proximate to or within the chamber interior volume 120 to ignite the process gas and generate the plasma 102. In some embodiments, bias power may also be provided from a bias power source (e.g., an RF bias power source 117) via a capacitively coupled bias plate (described below) to one or more electrodes (described below) disposed within the electrostatic chuck 150 to attract ions from the plasma toward the substrate S.

[0023] In some embodiments, such as where the chamber 100 is a PVD chamber, a target 166 can be disposed above the substrate and within the chamber interior volume 120, the target comprising source material to be deposited on the substrate S. The target 166 can be supported by a grounded conductive portion of the chamber 100, such as an aluminum adapter through a dielectric isolator. In other embodiments, the chamber 100 can include multiple targets in a multi-cathode arrangement for depositing different material layers using the same chamber.

[0024] A controllable DC power supply 168 may be coupled to the chamber 100 to apply a negative voltage or bias to the target 166. An RF bias power supply 117 may be coupled to the substrate support 124 to induce a negative DC bias on the substrate S. Additionally, in some embodiments, a negative DC self-bias may be formed on the substrate S during processing. In some embodiments, an RF plasma power supply 170 may also be coupled to the chamber 100 to apply RF power to the target 166 to facilitate control of the radial distribution of the deposition rate on the substrate S. In operation, ions in the plasma 102 generated in the chamber 100 react with source material from the target 166. The reaction causes the target 166 to emit atoms of the source material, which are then directed toward the substrate S, thereby depositing material.

[0025] Will refer to FIG. 2A to FIG. 2C The following description is given. Figure 2A A schematic cross-sectional view of an upper portion of electrostatic chuck 200 is depicted in accordance with at least some embodiments of the present disclosure. Figure 2B A schematic cross-sectional view of a lower portion of electrostatic chuck 200 is depicted in accordance with at least some embodiments of the present disclosure. Figure 2C Depiction Figure 2B2 is a schematic close-up cross-sectional view of a portion of an electrostatic chuck of FIG. The electrostatic chuck 200 includes a dielectric disk 202 having a support surface 204 for supporting a substrate, an opposing second surface 206, and at least one clamping electrode 208 disposed within the dielectric disk 202 between the support surface 204 and the second surface 206. The dielectric disk 202 further includes a plurality of coolant channels 210 also disposed within the dielectric disk 202 between the support surface 204 and the second surface 206. The plurality of coolant channels 210 may be formed in the dielectric disk 202, or may include non-permeable lines to prevent leakage of the cryogenic medium. Figure 2A As shown, the upper portion of the electrostatic chuck 200 is disposed within a housing 221 having a dish-like shape. The housing 221 also includes additional features necessary for the process flow, such as housing lift pin holes 223 ( Figure 2A These housing lift pin holes align with corresponding disk lift pin holes 225 to allow corresponding lift pins 240 ( Figure 2A A) is shown in FIG. 1 , passing through the support surface 204 and lifting the substrate off the support surface.

[0026] In some embodiments, a cryogenic manifold 212 is coupled to the second surface 206 of the dielectric disk 202. The cryogenic manifold 212 includes a coolant inlet 214 and a coolant outlet 216, both of which are fluidly coupled to the plurality of coolant channels 210. A shaft assembly 218 is coupled to the cryogenic manifold 212 at a first end 220 of the shaft assembly 218. The shaft assembly 218 includes a central opening 222 extending through the shaft assembly 218, through which the cryogenic medium supply / return tube (discussed below) extends. The shaft assembly 218 includes a shaft 224 and a flexure coupling 226. The shaft 224 and the flexure coupling 226 include a first central channel 228 and a second central channel 230, respectively, which together form the central opening 222. The flexure coupling 226 is configured to maintain the dielectric disk 202 substantially horizontal during rotation of the electrostatic chuck 200.

[0027] A drive assembly 227 is coupled to the shaft assembly 218 to rotate the shaft assembly 218 and the dielectric disk 202. A slip ring 232 (discussed below) is coupled to the first end 234 of the shaft 224 to facilitate coupling of power from a power source 236 to various components of the electrostatic chuck 200, such as, for example, one or more chucking electrodes 208, one or more thermocouples 241, etc. In some embodiments, one or more power couplings 243 (first power couplings) may extend through a portion of the slip ring 232 that rotates and into the bottom of the shaft 224. The power coupling 243 is electrically coupled to a second power coupling 245 that extends through a lower portion of a flexure coupling 226 and into an upper portion of the shaft 224. The flexure coupling 226 is coupled to a second end 242 of the shaft 224 opposite the slip ring 232. In some embodiments, a bearing assembly 233 is disposed about the flexure coupling 226 to provide additional support / rigidity to the upper portion of the electrostatic chuck 200 , especially during rotation.

[0028] A cryogenic supply chamber 244 is coupled to the shaft assembly 218 at a second end 247 opposite the first end 220 of the shaft assembly 218 to supply a cryogenic medium to the dielectric disk 202. The cryogenic medium supplied to the dielectric disk 202 by the cryogenic supply chamber 244 is between about 5 Kelvin and about 293 Kelvin. In some embodiments, the cryogenic medium may be liquid nitrogen, liquid helium mixed refrigerant gas, or the like.

[0029] To facilitate delivery of the cryogenic medium from the cryogenic supply chamber 244 to the dielectric disk 202, a supply tube 246 is coupled to the cryogenic supply chamber 244 at a first end 248 of the supply tube 246 and is coupled to the coolant inlet 214 of the cryogenic manifold 212 at a second end 250 of the supply tube 246 to supply the cryogenic medium to the plurality of coolant channels 210. In some embodiments, the supply tube 246 extends through the central opening 222 and is concentric with the shaft assembly 218.

[0030] To facilitate the return of the cryogenic medium to the cryogenic supply chamber 244 after the cryogenic medium flows through the plurality of coolant channels 210, a return pipe 252 is coupled to the coolant outlet 216 of the cryogenic manifold 212 at a first end 254 of the return pipe 252, and is coupled to the cryogenic supply chamber 244 at a second end 256 of the return pipe 252. In some embodiments, and as Figure 2A , Figure 2B As shown, the return pipe 252 extends through the central opening 222 and is disposed within and concentric with the supply pipe 246. In some embodiments, in order to minimize or substantially prevent heat transfer between the cryogenic medium flowing through the supply pipe 246 and the used cryogenic medium flowing through the return pipe 252, as shown in FIG. Figure 2CThe illustrated insulation layer 258 may be disposed on the outer surface of the supply tube 246. In some embodiments, the insulation layer 258 may be a coating, such as polytetrafluoroethylene, ceramic, or the like. In some embodiments, the insulation layer 258 may alternatively be a ceramic tube, wherein the supply tube 246 is inserted into the ceramic tube.

[0031] The cryogenic supply chamber 244 includes a chamber body 260 defining an interior volume 262. A feedthrough block 264 coupled to a cooler 266 for supply and return of a cryogenic medium is disposed within the interior volume 262. The feedthrough block 264 includes a feedthrough inlet 268, which is fluidly coupled to the supply tube 246, and a feedthrough outlet 270, which is fluidly coupled to the return tube 252. Since the cryogenic medium flowing through the feedthrough block 264 is at such a low temperature, ice or frost may accumulate on the feedthrough block 264. To avoid such ice accumulation, a vacuum pump 272 is fluidly coupled to the interior volume 262 via a vacuum port 274 formed in the chamber body 260 to maintain the interior volume 262 at a vacuum pressure. In some embodiments, the vacuum pump 272 is a roughing pump that is configured to maintain the pressure in the interior volume at approximately a rough vacuum pressure. While the supply tube 246 and the return tube 252 rotate, the feed-through block 264 remains stationary.

[0032] In some embodiments, the electrostatic chuck 200 may further include a sealing tube 276 coupled to the lower portion of the return tube 252 and concentric with the return tube 252. The sealing tube 276 is configured to seal the effective volume of the cryogenic supply chamber 244 at a rough vacuum pressure from the processing volume (e.g., the processing volume 119) at a processing pressure. To achieve such a seal, the sealing tube 276 includes a ceiling portion 278 and an open bottom end 280, the ceiling portion being coupled to the lower portion of the return tube 252. In some embodiments, the ceiling portion 278 is welded to the return tube 252. The return tube 252 extends through a portion of the sealing tube 276 and terminates at a point within the sealing tube 276. In some embodiments, an annular seal 261 may be disposed around the bottom of the sealing tube 276 to isolate the rough vacuum environment below the annular seal 261 from the processing vacuum environment above the annular seal 261.

[0033] In some embodiments, a bellows 282 is coupled to a lowermost surface 284 of the return tube 252 and is disposed within the sealing tube 276. The bellows 282 fluidly couples the return tube 252 to the feedthrough outlet 270. The bellows 282 is configured to compensate for thermal expansion of the return tube 252, any misalignment of the return tube 252 relative to the supply tube 246, and any relaxation caused by inertia caused by the rotation of the electrostatic chuck 200. In some embodiments, the bellows 282 is formed of stainless steel.

[0034] To facilitate cooling transfer to a substrate disposed above the dielectric disk 202, the electrostatic chuck 200 further includes a backside gas delivery system 286 fluidly coupled to the dielectric disk 202 to supply a backside gas to a plurality of backside gas outlets 288 formed through the support surface 204 near the periphery of the dielectric disk 202. In some embodiments, the backside gas delivery system 286 includes a rotary feedthrough 290 disposed about and concentric with the axis 224, a backside gas conduit 292 coupled to the second end 242 of the axis 224, and a backside gas manifold 294 coupled to the backside gas conduit 292 opposite the axis 224. The rotary feedthrough 290 includes a stationary housing 251 and a cylindrical portion 253 disposed within the housing and rotatable. Two annular bearing assemblies 255, 257 are disposed between the housing 251 and the cylindrical portion 253. The rotary feedthrough 290 further includes a backside gas coupling 296 to facilitate coupling of a backside gas source to the rotary feedthrough 290. The backside gas manifold 294 is disposed between the cryogenic manifold 212 and the flexure coupling 226 and includes a manifold channel 298 that fluidly couples the backside gas conduit 292 to the backside gas inlet 203 in the dielectric disk 202 along with corresponding conduits 299 formed in the cryogenic manifold 212 and aligned with the manifold channel 298. The shaft 224 includes a backside gas channel 265 to fluidly couple the backside gas coupling 296 to the backside gas conduit 292.

[0035] In some embodiments, the shaft 224 includes an annular recess 229 formed in the outer surface 231 of the shaft 224 and disposed adjacent to the backside gas coupling 296. The backside gas passage 265 fluidly couples the annular recess 229 to the backside gas conduit 292, such that backside gas from the backside gas coupling 296 flows into the annular recess 229, through the backside gas passage 265 of the shaft 224, through the backside gas conduit 292, through the backside gas inlet 203, and through the plurality of backside gas outlets 288. To prevent backside gas leakage, a first annular seal 239 is disposed above the backside gas coupling 296 and a second annular seal 249 is disposed below the backside gas coupling 296, both of which are disposed between the housing 251 and the cylindrical portion 253. In some embodiments, the first annular seal element 239 and the second annular seal element 249 are ferrofluidic seals. In addition, the third annular sealing element 235 is arranged around the axis 224 above the back gas coupling 296, and the fourth annular sealing element 237 is arranged around the axis 224 below the back gas coupling 296, so that the rough vacuum pressure environment below the third annular sealing element 235 and the fourth annular sealing element 237 is fluidly isolated from the processing vacuum pressure environment above the third annular sealing element 235 and the fourth annular sealing element 237.

[0036] In order to control the cooling rate of the substrate disposed above the dielectric disk 202, the flow rate of the backside gas and the clamping force provided by the clamping electrode are controlled to achieve the required pressure below the substrate and the substrate clamping that produces the desired cooling rate. One or more thermocouples 241 can monitor the temperature of the dielectric disk 202. The cryogenic medium supply to the plurality of coolant channels 210 and the flow rate of the backside gas are controlled based on the temperature readings provided by the thermocouples 241.

[0037] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof.

Claims

1. An electrostatic chuck, comprising: a dielectric disk having a support surface and an opposing second surface, the support surface being configured to support a substrate, wherein at least one clamping electrode is disposed within the dielectric disk between the support surface and the second surface, and wherein a plurality of coolant channels are disposed entirely within the dielectric disk; a cryogenic manifold coupled to the second surface of the dielectric disk beneath the coolant channels and having a coolant inlet and a coolant outlet, both of which are fluidly coupled to the plurality of coolant channels; a shaft assembly coupled to the cryogenic manifold at a first end thereof, wherein the shaft assembly includes a central opening extending through the shaft assembly, wherein the shaft assembly includes a flexure coupling at the first end of the shaft assembly and a shaft coupled to the flexure coupling, wherein the flexure coupling and the shaft are configured to maintain the dielectric disk substantially horizontal during rotation; a backside gas manifold disposed between the cryogenic manifold and the flexure coupling, the backside gas manifold having manifold channels aligned with corresponding conduits formed in the cryogenic manifold to fluidly couple the backside gas conduits to backside gas inlets in the dielectric disk; a cryogenic supply chamber coupled to the shaft assembly at a second end of the shaft assembly opposite the first end; a supply tube coupled to the cryogenic supply chamber at a first end thereof to receive a cryogenic medium and coupled to the coolant inlet at a second end of the supply tube to supply the cryogenic medium to the plurality of coolant passages, wherein the supply tube extends through the central opening and is concentric with the shaft assembly; and a return tube coupled at a first end thereof to the coolant outlet and coupled at a second end of the return tube to the cryogenic supply chamber to return the cryogenic medium to the cryogenic supply chamber after the cryogenic medium flows through the plurality of coolant channels, wherein the return tube extends through the central opening and is concentric with the supply tube, and wherein the supply tube is disposed within the return tube and the backside gas conduit is spaced apart from an exterior of the supply tube; a bearing assembly disposed about the flexure coupling and vertically disposed between the flexure coupling and the dielectric disk; as well as A drive assembly is coupled to the shaft assembly and is configured to rotate the shaft assembly and the dielectric disk.

2. The electrostatic chuck of claim 1, further comprising: A slip ring is coupled to the shaft at an end of the shaft opposite the flexure coupling to facilitate coupling of power from a power source to the at least one clamping electrode.

3. The electrostatic chuck of claim 1, further comprising a housing having a disk-like shape disposed around the dielectric disk and the cryogenic manifold.

4. The electrostatic chuck of claim 1, further comprising: a backside gas delivery system fluidly coupled to the dielectric disk, wherein the backside gas delivery system comprises: a rotary feedthrough disposed about and concentric with the axis and having a backside gas coupling, wherein the rotary feedthrough includes a stationary housing and a rotatable cylindrical portion disposed within the housing, and wherein two annular bearing assemblies are disposed between the stationary housing and the rotatable cylindrical portion; the backside gas conduit coupled to the second end of the shaft; and the backside gas manifold coupled to the backside gas conduit opposite the axis, A backside gas passage is formed through the shaft to fluidly couple the backside gas coupling to the backside gas conduit.

5. The electrostatic chuck of claim 4, wherein the shaft includes an annular recess formed in an outer surface of the shaft, wherein the annular recess is disposed adjacent the backside gas coupling, and wherein the backside gas channel fluidly couples the annular recess to the backside gas conduit.

6. The electrostatic chuck of claim 4, further comprising: a first annular sealing element disposed above the back gas coupling between the stationary housing and the rotatable cylindrical portion; and a second annular sealing element disposed below the back gas coupling between the stationary housing and the rotatable cylindrical portion, The first annular sealing element and the second annular sealing element are configured to prevent leakage of backside gas supplied through the backside gas coupling.

7. The electrostatic chuck of any one of claims 1 to 6, wherein the cryogenic supply chamber comprises: a chamber body defining an interior volume; and A feedthrough block has a feedthrough inlet and a feedthrough outlet, the feedthrough inlet being fluidly coupled to the supply tube and the feedthrough outlet being fluidly coupled to the return tube.

8. The electrostatic chuck of claim 7, further comprising: A vacuum pump is fluidly coupled to the interior volume via a vacuum port formed in the chamber body to maintain the interior volume at a vacuum pressure.

9. The electrostatic chuck of claim 7, further comprising: A sealing tube coupled to a lower portion of the return tube and arranged to be concentric with the return tube, wherein the return tube extends through a portion of the sealing tube, wherein the sealing tube includes a ceiling portion and an open bottom end, and wherein the ceiling portion is coupled to the lower portion of the return tube to seal off the effective volume of the low-temperature supply chamber.

10. The electrostatic chuck of claim 9, further comprising: A bellows is coupled to a lowermost surface of the return tube and disposed within the sealing tube, wherein a volume fluid within the bellows is coupled to the feed-through outlet.

11. The electrostatic chuck of claim 10, wherein the bellows is formed of stainless steel and is welded to the lowermost surface of the return tube.

12. The electrostatic chuck of any one of claims 1 to 6, further comprising: A heat insulating layer is disposed on an outer surface of the supply pipe.

13. A processing chamber comprising: a chamber body having an interior volume; and The electrostatic chuck of claim 1, wherein the electrostatic chuck is disposed within a lower portion of the interior volume.

14. The processing chamber of claim 13, further comprising: A cooler is coupled to the cryogenic supply chamber to supply a cryogenic medium to the electrostatic chuck via the cryogenic supply chamber.

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