Rotating biasable pedestal and electrostatic chuck in a semiconductor processing chamber - Patents.com

Abstract

Provided herein are embodiments of a substrate support. In some embodiments, a substrate support for use in a chemical vapor deposition (CVD) chamber includes a pedestal for supporting a substrate, the pedestal including a dielectric plate connected to a pedestal body, a rotary union connected to the pedestal, the rotary union including a stationary housing disposed around a rotor, a drive assembly connected to the rotary union, a coolant union connected to the rotary union and having a coolant inlet fluidly connected to a coolant channel disposed in the pedestal via a coolant line, an RF rotary joint connected to the coolant union and having an RF connector configured to connect the pedestal to an RF bias power supply, and an RF conduit extending from the RF connector through a central opening in the pedestal body to the pedestal for providing an RF bias to the pedestal.

Description

[Technical field]

[0001] TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate generally to substrate processing equipment. [Background technology]

[0002] A substrate processing system typically includes a processing chamber for performing a desired process, such as a deposition process, on one or more substrates disposed therein. Chemical vapor deposition (CVD) processing chambers are often used in the semiconductor industry to deposit thin films on substrates supported by a substrate support disposed in the CVD processing chamber. CVD processing chambers may employ plasma technology to perform flowable CVD gapfill processing. However, achieving high quality films in CVD gapfill processes is challenging as substrate feature sizes become smaller.

[0003] SUMMARY OF THE DISCLOSURE Accordingly, the present inventors have provided an embodiment of an improved substrate support for use in a CVD chamber. Summary of the Invention

[0004]

[0004] An embodiment of a substrate support is provided herein. In some embodiments, a substrate support for use in a chemical vapor deposition (CVD) chamber includes a pedestal for supporting a substrate, the pedestal including a dielectric plate connected to a pedestal body, a rotary union connected to the pedestal, the rotary union including a stationary housing disposed around a rotor, a drive assembly connected to the rotary union and configured to rotate the rotor to rotate the pedestal, a coolant union connected to the rotary union and having a coolant inlet fluidly connected to a coolant channel disposed in the pedestal via a coolant line, an RF rotary joint connected to the coolant union and having an RF connector configured to connect the pedestal to an RF bias power supply, and an RF conduit extending from the RF connector through a central opening in the pedestal body to the pedestal to provide an RF bias to the pedestal.

[0005]

[0005] In some embodiments, a substrate support for use in a chemical vapor deposition (CVD) chamber includes a pedestal supporting a substrate, the pedestal including a dielectric plate connected to a pedestal body and including a monopolar or bipolar electrode; a rotary union connected to the pedestal, the rotary union including a stationary housing disposed about the rotor; a drive assembly connected to the rotary union and configured to rotate the rotor to rotate the pedestal; a coolant union connected to the rotary union and having a coolant inlet fluidly connected to a coolant channel disposed in the pedestal via a coolant line; an RF rotary joint connected to the coolant union and having an RF connector configured to connect the pedestal to an RF bias power supply; an RF conduit extending from the RF connector to the pedestal through a central opening in the pedestal body; a bellows assembly disposed about the pedestal body; and a lift assembly connected to the bellows assembly and configured to selectively raise or lower the pedestal.

[0006] In some embodiments, a chemical vapor deposition (CVD) processing chamber includes a chamber body defining an interior space, a showerhead disposed in the interior space for supplying one or more process gases to the interior space, a substrate support disposed in the interior space opposite the showerhead, the substrate support comprising a pedestal for supporting a substrate, the pedestal including a dielectric plate connected to the pedestal body, a rotary union connected to the pedestal, the rotary union including a stationary housing disposed around a rotor, a drive assembly connected to the rotary union and configured to rotate the rotor to rotate the pedestal, a coolant union connected to the rotary union and having a coolant inlet fluidly connected to a coolant channel disposed in the pedestal via a coolant line, an RF rotary joint connected to the coolant union and having an RF connector, an RF conduit extending from the RF connector to the pedestal through a central opening in the pedestal body, and an RF bias power supply connected to the RF conduit and configured to share RF power to the dielectric plate via the RF conduit.

[0007]

[0007] Other and further embodiments of the present disclosure are described below.

[0008]

[0008] The embodiments of the present disclosure, briefly summarized above and described in more detail below, can be understood by reference to the exemplary embodiments of the present disclosure illustrated in the accompanying drawings. However, since the present disclosure is open to other equally effective embodiments, the accompanying drawings depict only typical embodiments of the present disclosure and therefore should not be considered as limiting the scope. [Brief description of the drawings]

[0009] [Figure 1]

[0009] FIG. 1 shows a cross-sectional schematic diagram of an apparatus for depositing a film according to at least some embodiments of the present disclosure. [Diagram 2]

[0010] 1 shows a cross-sectional schematic view of a substrate support according to at least some embodiments of the present disclosure. [Diagram 3]

[0011] 1 illustrates a cross-sectional view of a pedestal of a substrate support in accordance with at least some embodiments of the present disclosure. [Figure 4]

[0012] 1 shows a cross-sectional schematic view of a substrate support according to at least some embodiments of the present disclosure. [Diagram 5]

[0013] 1 illustrates a cross-sectional view of a pedestal of a substrate support in accordance with at least some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010]

[0014] For ease of understanding, the same reference numbers have been used, where possible, to designate identical elements common to the figures. The figures are not drawn to scale and may be simplified for clarity. Elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

[0011]

[0015] Provided herein are embodiments of a substrate support. The substrate support provided herein advantageously includes a rotating biasable pedestal for use in a CVD processing chamber. The combination of the rotating and biasing features of the pedestal improves gap filling of high aspect ratio features, gap filling uniformity, and high density film quality. The substrate support includes a radio frequency (RF) rotary joint configured to provide continuous wave or pulsed RF bias power to the pedestal.

[0012]

[0016] FIG. 1 shows a cross-sectional schematic view of an apparatus 100 for depositing a film according to at least some embodiments of the present disclosure. The apparatus 100 generally includes a chemical vapor deposition (CVD) chamber 101 for depositing a layer according to embodiments of the present disclosure. In some embodiments, the apparatus 100 may include a dual or twin chamber configuration with two CVD chambers 101, as shown in FIG. 1. In some embodiments, the twin chamber has two separate internal spaces (one substrate per processing region for processing two substrates) such that the flow rate obtained in each region is about half the flow rate entering the apparatus 100. In some embodiments, the apparatus 100 is stand-alone. In some embodiments, the apparatus 100 is part of a multi-chamber processing tool.

[0013]

[0017] The apparatus 100 has a chamber body 102 that defines separate interior spaces 118, 120. Each of the interior spaces 118, 120 has a substrate support 128 disposed therein for supporting the substrate 115 within the CVD chamber 101. In some embodiments, the substrate support 128 includes a heating element (not shown). Preferably, each substrate support 128 is movably disposed in one of the interior spaces 118, 120 by a support shaft 126 that extends through a bottom of the chamber body 102 and is connected to a lift assembly 103.

[0014]

[0018] The interior spaces 118, 120 also generally include a gas distribution assembly 108 disposed through the chamber lid 104 to supply gases to the interior spaces 118, 120. In some embodiments, the gas distribution assembly 108 of each processing region includes a gas inlet passage 140 that supplies gases from a gas flow controller 119 into the showerhead 142. The gas flow controller 119 is typically used to control and adjust the flow rates of different process gases into the CVD chamber 101. Other flow control components may include liquid flow injection valves and liquid flow controllers (not shown) when liquid precursors are used. In some embodiments, the showerhead 142 includes an annular base plate 148, a faceplate 146, and a blocker plate 144 between the annular base plate 148 and the faceplate 146. The showerhead 142 includes a number of openings (not shown) through which gas mixtures are injected during processing.

[0015]

[0019] An RF (radio frequency) power supply 125 provides a bias potential to the showerhead 142 to facilitate the generation of a plasma between the showerhead assembly and the substrate support 128. In some embodiments, the RF power supply 125 is connected to the showerhead 142 through an RF match network 124. During a plasma enhanced chemical vapor deposition process, the substrate support 128 can function as a cathode to generate an RF bias in the chamber body 102. The substrate support 128 is advantageously electrically connected to a bias power supply 150 to generate a bias voltage on the substrate 115 in the CVD chamber 101. Typically, an RF voltage is applied to the cathode while the chamber body 102 is electrically grounded. Power applied to the substrate support 128 creates a substrate bias in the form of a negative voltage on the top surface of the substrate 115. The negative voltage is used to attract ions from the plasma formed in the CVD chamber 101 to the top surface of the substrate 115. In some embodiments, the bias power supply 150 is connected to the substrate support 128 through an RF match network 152.

[0016]

[0020] During processing, the process gas is radially dispersed across the substrate surface to perform the gap-fill process. A plasma is formed from one or more process gases or gas mixtures by applying RF energy from an RF power source 125 to a showerhead 142, which acts as a powered electrode. Film deposition occurs when the substrate 115 is exposed to the plasma and reactive gases provided therein. Typically, the chamber walls 112 are grounded. The RF power source 125 may provide single or mixed frequency RF signals to the showerhead 142 to promote decomposition of any gases introduced into the interior spaces 118, 120.

[0017]

[0021] The system controller 134 controls the functions of various components such as the RF power supply 125, bias power supply 150, lift assembly 103, gas flow controller 119, and other associated chamber and / or process functions. The system controller 134 executes system control software stored in memory 138, which in a preferred embodiment is a hard disk drive and may include analog and digital input / output boards, interface boards, and stepper motor controller boards. Optical and / or magnetic sensors are generally used to move and determine the position of the movable mechanical assemblies. The above description of the CVD chamber 101 is primarily for illustrative purposes, and other plasma processing chambers may also be employed to carry out embodiments of the present invention.

[0018]

[0022] During deposition on the substrate 115, a controlled plasma is typically formed in the chamber adjacent to the substrate 115 by RF energy applied to a showerhead using an RF power supply 125, as depicted in FIG. 1. Alternatively or additionally, RF power may be supplied to the substrate support 128. The plasma may be generated using high frequency RF (HFRF) power as well as low frequency RF (LFRF) power (e.g., dual frequency RF), constant RF, pulsed RF, or any other suitable plasma generating technique. The RF power supply 125 may provide a single frequency RF between about 1 MHz and about 300 MHz. In addition, the RF power supply 125 may also provide a single frequency LFRF between about 300 Hz and about 1,000 kHz to provide mixed frequencies and promote decomposition of reactive species in the process gases introduced into the process chamber. The RF power may be cycled or pulsed to reduce heating of the substrate and increase porosity of the deposited film. Suitable RF powers may range between about 10 W and about 5,000 W, preferably between about 200 W and about 3,000 W. Suitable LFRF powers may range between about 0 W and about 5,000 W, preferably between about 0 W and about 500 W.

[0019]

[0023] During deposition, the bias power supply 150 can be configured to provide between about 1 kW and about 3 kW of power. In some embodiments, the bias power supply 150 can be configured to provide bias power at a single frequency RF of about 0.5 MHz to about 30 MHz, for example, the frequency range can be from about 0.5 MHz to about 15 MHz. In some embodiments, the bias power supply 150 can be configured to provide bias power at multiple RF frequencies. In some embodiments, during deposition, the substrate 115 can be maintained at a temperature between about -20°C and about 100°C.

[0020]

[0024] FIG. 2 illustrates a cross-sectional schematic view of a substrate support 128 in accordance with at least some embodiments of the present disclosure. The substrate support 128 includes a pedestal 204 having a support surface 268 for supporting a substrate 115. The pedestal 204 generally includes a dielectric plate 206 connected to a pedestal body 210. In some embodiments, as shown in FIGS. 2 and 3, the pedestal 204 includes a monopolar electrode 208 disposed within the dielectric plate 206. The pedestal body 210 includes a ground plate 216 connected to a stem 218. In some embodiments, the ground plate 216 includes a plurality of coolant channels 214 for flowing a coolant. The coolant can be any suitable coolant, such as water, glycol, polyether fluid, etc. The pedestal body 210 includes a central opening 222 extending through the ground plate 216 and the stem 218. The stem 218 provides a conduit for supplying, for example, backside gases, fluids, coolants, power, etc. to the remainder of the pedestal 204 .

[0021]

[0025] In some embodiments, a bellows assembly 212 is disposed about the pedestal body 210. For example, the bellows assembly 212 can be disposed about the stem 218 and through the floor 202 of the chamber wall 112. The bellows assembly 212 can include an upper flange 224 connected to the floor 202 to provide a flexible seal that allows for vertical positioning of the pedestal 204 while preventing loss of vacuum from within the CVD chamber 101. A lift assembly, for example, the lift assembly 103, is connected to the bellows assembly 212 and is configured to selectively raise or lower the pedestal 204 within the interior spaces 118, 120 between a processing position (shown in FIG. 1 ) and a lower transfer position (not shown).

[0022]

[0026] The rotary union 230 is connected to the pedestal 204 and configured to facilitate rotation of the pedestal 204. The rotary union 230 generally includes a stationary housing 226 disposed about a rotor 232. The rotor 232 is connected to the pedestal 204 such that the pedestal 204 rotates with the rotor 232. The rotor 232 may rotate relative to the stationary housing 226 using any suitable means. For example, one or more first bearings 234 may be disposed between the rotor 232 and the stationary housing 226 to facilitate rotation therebetween. In some embodiments, the lift assembly 103 is connected to the stationary housing 226 and configured to raise or lower the rotary union 230 relative to the floor 202 to raise or lower the pedestal 204. In some embodiments, the stationary housing 226 includes a central opening 228. In some embodiments, the stem 218 extends at least partially through the central opening 228.

[0023]

[0027] In some embodiments, rotary union 230 includes a second stationary housing 236 disposed about a lower portion of rotor 232. In some embodiments, second stationary housing 236 is connected to a lower portion of stationary housing 226. One or more first bearings 234 may be disposed between stationary housing 226 and rotor 232, second stationary housing 236 and rotor 232, or both.

[0024]

[0028] The drive assembly 238 is connected to the rotary union 230 and configured to rotate the rotor 232, which in turn rotates the pedestal 204, via any suitable means. For example, the drive assembly 238 may include a motor connected to one or more belts, pulleys, tracks, or gears. In some embodiments, the drive assembly 238 is configured to rotate the pedestal 204 at a rotational speed of about 10 revolutions per minute or less. In some embodiments, the drive assembly 238 is connected to the rotor 232 through an opening in the second stationary housing 236. In some embodiments, the drive assembly 238 is connected to the rotor 232 through an opening in the stationary housing 226 or a gap between the stationary housing 226 and the second stationary housing 236.

[0025]

[0029] The coolant union 240 is connected to the rotary union 230 and rotates therewith. The coolant union 240 includes a coolant inlet 244 fluidly connected to the coolant channel 214 of the pedestal 204. For example, a coolant line 248 may extend from the coolant inlet 244 through the coolant union 240, through the rotor 232, and through the stem 218 to the coolant channel 214. A coolant source 242 may be connected to the coolant inlet 244 to flow a coolant, such as any of the coolants described above, through the coolant channel 214 to control the temperature of the pedestal 204. A coolant return line (not shown) may extend from the coolant channel 214 back to the coolant union 240. In some embodiments, an upper portion of the coolant union 240 is disposed within a portion of the second stationary housing 236 of the rotary union 230. In some embodiments, one or more second bearings 246 are disposed between the coolant union 240 and the second stationary housing 236 to facilitate rotational movement therebetween.

[0026]

[0030] The RF rotary joint 250 is connected to the coolant union 240 and is configured to connect the bias power supply 150 to the pedestal 204. In some embodiments, the RF rotary joint 250 generally includes an RF housing 254 and an RF connector 252 disposed within the RF housing 254. In some embodiments, the RF connector 252 includes an upper portion 256 and a lower portion 258, the lower portion 258 being configured to rotate relative to the upper portion 256 via suitable means, such as via one or more bearings disposed therebetween. In some embodiments, the upper portion 256 and the lower portion 258 are a single component. In some embodiments, the upper portion 256 and the lower portion 258 include features to facilitate quick connection or disconnection therebetween. In some embodiments, an RF elbow connector 260 is connected at one end to the lower portion 258 and at an opposite end to the bias power supply. In some embodiments, the RF connector 252 is configured to provide a single channel RF connection. In some embodiments, the RF connector 252 is configured to provide RF power of about 0.8 kW to about 1.2 kW at frequencies between about 0.5 MHz and about 15 MHz.

[0027]

[0031] In some embodiments, a lower portion of the coolant union 240 extends into the RF housing 254. In some embodiments, the RF rotary joint 250 includes an insulating adapter ring 264 disposed about a lower portion of the coolant union 240. In some embodiments, the RF rotary joint 250 includes a mounting ring 262 connected to the insulating adapter ring 264. The RF connector 252 can be attached to the mounting ring 262 to connect the RF connector 252 to the coolant union 240.

[0028]

[0032] The RF conduit 270 extends from the RF connector 252 through the central opening 222 of the pedestal body 210 to the pedestal 204 and provides RF bias power to the pedestal 204. The RF conduit 270 rotates with the pedestal 402. In some embodiments, the RF conduit 270 extends from the mounting ring 262 to the monopolar electrode 208 in the dielectric plate 206. In some embodiments, the RF conduit 270 is a metal rod that extends through the coolant union 240 and the rotary union 230. In some embodiments, the metal rod is made of brass. In some embodiments, the metal rod is silver plated. In some embodiments, the RF conduit 270 is located in the center of the substrate support 128. In some embodiments, the coolant line 248 (and the coolant return line) are located radially outward of the RF conduit 270.

[0029]

[0033] In some embodiments, an insulator tube 272 is disposed around the RF conduit 270 to insulate the RF conduit 270. In some embodiments, the insulator tube 272 is made of a polymeric material, such as polytetrafluoroethylene (PTFE). In some embodiments, the insulator tube 272 extends from the mounting ring 262 to the dielectric plate 206.

[0030]

[0034] In some embodiments, a ground tube 274 is disposed around at least a portion of the insulating tube 272 and connected to a ground to facilitate grounding of the pedestal body 210. In some embodiments, the ground tube 274 extends from the RF connector 252 to the pedestal body 210. In some embodiments, the ground tube 274 includes a tubular portion and an upper flange extending radially outward from the tubular portion. In some embodiments, the upper flange of the ground tube 274 is disposed between the pedestal body 210 and the rotor 232. In some embodiments, the upper flange of the ground tube 274 includes one or more openings corresponding to the coolant line 248 (and the coolant return line). In some embodiments, the ground tube 274 is made of aluminum. In some embodiments, the ground tube 274 is coated with nickel.

[0031]

[0035] FIG. 3 illustrates a cross-sectional view of the pedestal 204 of the substrate support 128 according to at least some embodiments of the present disclosure. In some embodiments, the pedestal 204 includes an insulator plate 302 disposed between the dielectric plate 206 and the grounded plate 216 of the pedestal body 210 to insulate the dielectric plate 206, which is RF hot, from the grounded plate 216, which may be grounded. In some embodiments, the dielectric plate 206 is made of a ceramic material. In some embodiments, the dielectric plate 206 is made of aluminum nitride (AlN). The monopolar electrode 208 may include a plate, mesh, or the like. A metallic rod connector 304 is disposed between the RF conduit 270 and the monopolar electrode 208 and configured to electrically connect the RF conduit 270 to the monopolar electrode 208. In some embodiments, the rod connector 304 has a recess 312 to accommodate the upper end of the RF conduit 270. In some embodiments, the rod connector 304 has an inverted U-shaped cross-section. In some embodiments, the wall formed by the recess 312 of the rod connector 304 is disposed between the RF conduit 270 and the insulator tube 272 .

[0032]

[0036] In some embodiments, the pedestal 204 includes an upper edge ring 308 having an annular shape and disposed on a peripheral edge of the dielectric plate 206. The upper edge ring 308 is configured to surround the substrate 115 and to help guide or direct the plasma proximate to the edge of the substrate 115. The upper edge ring 308 may also help prevent damage to the dielectric plate 206 by shielding the dielectric plate 206 from the plasma during use. In some embodiments, the upper edge ring 308 is made of a ceramic material, such as aluminum oxide.

[0033]

[0037] In some embodiments, the pedestal 204 includes a lower edge ring 306 having an annular shape and disposed on an outer sidewall of the dielectric plate 206. The lower edge ring 306 is configured to surround and shield the dielectric plate 206 from the plasma during use. In some embodiments, the lower edge ring 306 is made of a ceramic material, such as aluminum oxide. In some embodiments, the lower edge ring 306 rests on the insulator plate 302 such that only the support surface 268 of the dielectric plate 206 is exposed to the plasma.

[0034]

[0038] In some embodiments, the pedestal 204 includes one or more lift pins 330 disposed therein for selectively raising or lowering the substrate 115 from or onto the pedestal 204. For example, the one or more lift pins 330 extend through the ground plate 216 and the dielectric plate 206 of the pedestal body 210. In some embodiments, the one or more lift pins 330 include a wider upper portion 332, a wider lower portion 336, and a narrower central portion 334. In some embodiments, the dielectric plate 206 includes one or more recesses 328 corresponding to the wider upper portions 332 of the one or more lift pins 330 such that when in the upper processing position, the wider upper portions 332 extend completely into the one or more recesses 328 such that the substrate 115 rests directly on the support surface 268. When the pedestal 204 is moved to the lower transfer position (as shown in FIG. 3 ), the wider lower portions 336 of the one or more lift pins 330 are pressed against the floor 202 of the CVD chamber 101 and the wider upper portions 332 of the one or more lift pins 330 are lifted above the support surface 268. In some embodiments, the lower surface of the ground plate 216 includes one or more second recesses 324 that correspond to the wider lower portions 336. In some embodiments, the wider upper portions 332 have a smaller outer diameter than the wider lower portions 336.

[0035]

[0039] 4 illustrates a cross-sectional schematic view of a substrate support according to at least some embodiments of the present disclosure. In some embodiments, as shown in FIG. 4, the pedestal 204 includes a bipolar electrode disposed within a dielectric plate 206 configured to electrostatically chuck the substrate 115, or an electrostatic chuck having one or more chuck electrodes 406. Cross-hatching of the dielectric plate 206 is not shown in FIG. 4 to improve visibility of the chuck electrode(s) 406. The chuck electrode(s) 406 are connected to a DC power supply 410 configured to provide DC power to the chuck electrode(s) 406. In some embodiments, the dielectric plate 206 is made of aluminum oxide.

[0036]

[0040] In some embodiments, the pedestal 204 includes a cooling plate 412 disposed between the dielectric plate 206 and the ground plate 216. The cooling plate 412 may be made of a metal, such as aluminum. In some embodiments, the ground plate 216 includes an outer lip 404 that extends upwardly from the ground plate 216 at a peripheral edge of the ground plate 216 to surround the cooling plate 412. In some embodiments, the cooling plate 412, rather than the ground plate 216, includes a number of coolant channels 214 for flowing coolant. In some embodiments, the coolant line 248 may extend from the coolant inlet 244 through the coolant union 240, through the rotor 232, through the stem 218, through the ground plate 216, and into the coolant channel 214. In some embodiments, the coolant line 248 extends through the ground tube 274. A coolant return line (not shown) may extend from the coolant channel 214 back to the coolant union 240.

[0037]

[0041] In some embodiments, the RF rotary joint 250 is configured to provide between about 0.5 kW and about 3 kW of RF power from the bias power supply 150 to the pedestal 204. In some embodiments, the RF rotary joint 250 is configured to provide three or more channels. In some embodiments, the RF conduit 270 includes a metal tube having a central opening 448. The RF conduit 270 is connected to the bias power supply 150 and includes a first channel. In some embodiments, one or more electrical lines 422 extend from the RF rotary joint 250 to the one or more chuck electrodes 406 through the central opening 448 of the metal tube. The one or more electrical lines 422 may include a DC conduit 422A for providing DC power to the one or more chuck electrodes 406. The DC conduit 422A may include two conduits corresponding to the second and third channels. The two DC conduits 422A may be electrical wires, cables, or the like. The one or more electrical lines 422 may also include a fiber optic cable 422B, as described in more detail below, for transmitting temperature readings of the one or more chuck electrodes 406.

[0038]

[0042] In some embodiments, the RF rotary joint 250 includes an RF connector 252 having a fixed portion 444 and a rotating portion 442, the rotating portion 442 configured to rotate with the pedestal 204 and the RF conduit 270. One or more third bearings 428 may be disposed between the rotating portion 442 and the fixed portion 444 to facilitate rotation therebetween. In some embodiments, the bias power supply 150 is connected to an RF input 452 of the fixed portion 444. In some embodiments, the one or more third bearings 428 are configured to connect RF bias power from the RF input 452 to the rotating portion 442 to the RF conduit 270 connected to the rotating portion 442.

[0039]

[0043] In some embodiments, the RF rotary joint 250 includes a purge gas inlet 416 fluidly connected to a central opening 448 of the metal tube and configured to purge the central opening 448 with a purge gas to prevent accumulation of moisture or contamination within the central opening 448. The purge gas inlet 416 may be connected to a purge source 420 having an inert gas, such as nitrogen, argon, helium, or the like.

[0040]

[0044] In some embodiments, the DC power supply 410 may be connected to a DC power input 446 in the stationary portion 444 of the RF rotary joint 250. In some embodiments, the DC power input 446, the purge gas inlet 416, and the RF input 452 are arranged around the RF rotary joint 250 along the same horizontal plate. In some embodiments, the DC power input 446, the purge gas inlet 416, and the RF input 452 are arranged around the RF rotary joint 250 along approximately 90 degree intervals. In some embodiments, the RF rotary joint 250 includes a fiber optic rotary joint 438. In such embodiments, an optical signal from the one or more chuck electrodes 406 is transmitted to the fiber optic rotary joint 438 via a fiber optic cable 422B of the one or more electrical lines 422 and then transmitted to a receiver 450 configured to process the optical signal to determine a temperature reading of the one or more chuck electrodes 406.

[0041]

[0045] In some embodiments, the substrate support 128 is configured to supply a backside gas to the support surface 268. In some embodiments, the rotary union 230 includes a backside gas inlet 414. In some embodiments, the substrate support 128 includes a backside gas line 434 that extends from the backside gas inlet 414 to the support surface 268, i.e., the upper surface, of the pedestal 204. The backside gas inlet 414 is coupled to a backside gas source 430. In some embodiments, the backside gas source 430 includes an inert gas, such as, for example, helium, nitrogen, argon, or the like.

[0042]

[0046] In some embodiments, the backside gas inlet 414 is located on an outer sidewall of the stationary housing 226 of the rotary union 230. However, the backside gas inlet 414 may be located on any other suitable surface of the rotary union 230. In some embodiments, the backside gas line 434 extends radially inward from the stationary housing 226 to a location within the rotor 232, then extends upward from a location within the rotor 232 to an upper surface of the rotor 232, through the ground tube 274, through the stem 218, through the ground plate 216, and into a backside gas channel 432 disposed within the cooling plate 412. The backside gas channel 432 extends substantially horizontally through the cooling plate 412 in any suitable pattern. The backside gas line 434 includes a plurality of second backside gas channels 418 that extend upward from the backside gas line 432 to the support surface 268 of the pedestal 204. In some embodiments, the backside gas channels 432 are disposed vertically above the coolant channels 214 .

[0043]

[0047] 5 illustrates a cross-sectional view of the pedestal 204 of the substrate support 128 in accordance with at least some embodiments of the present disclosure. In some embodiments, an insulator plate 502 is disposed between the cooling plate 412 and the grounded plate 216 to insulate the grounded plate 216 from the cooling plate 412, which is connected to the bias power supply 150 via an RF conduit 270. In some embodiments, a bonding layer 504 is disposed between the dielectric plate 206 and the cooling plate 412. In some embodiments, a seal 518 is disposed between the dielectric plate 206 and the cooling plate 412 around the bonding layer 504.

[0044]

[0048] In some embodiments, the RF conduit 270 includes an upper flange 526 that extends radially outward from the metal tube. In some embodiments, the upper flange 526 is disposed within the cooling plate 412. In some embodiments, an insulator plug 516 is disposed within the cooling plate 412 vertically above the RF conduit 270. In some embodiments, the DC conduit 422A extends from a central opening 448 of the RF conduit 270 through the insulator plug 516 to the chuck electrode(s) 406. In some embodiments, a porous plug 510 is disposed within the insulator plate 502 and cooling plate 412 around the lift pin(s) 330 to reduce or prevent arcing at the opening in the pedestal 204 for the lift pin(s) 330.

[0045]

[0049] In some embodiments, the pedestal 204 includes an upper edge ring 508 having an annular shape and disposed about the outer peripheral edge of the dielectric plate 206. In some embodiments, the upper edge ring 508 functions similarly and is made of similar materials as the upper edge ring 308 described above with respect to Figure 3. In some embodiments, the upper edge ring 508 includes a protrusion 532 on its bottom surface.

[0046]

[0050] In some embodiments, the pedestal 204 includes a lower edge ring 506 having an annular shape and disposed around an outer sidewall of the dielectric plate 206. The lower edge ring 506 is configured to surround the dielectric plate 206 and may advantageously reduce the possibility of arcing between the dielectric plate 206 and the outer lip 404 of the ground plate 216. In some embodiments, the lower edge ring 506 is made of a similar material as the lower edge ring 306. In some embodiments, the top surface of the lower edge ring 506 may include a recess for mating with the protrusion 532 of the upper edge ring 508.

[0047]

[0051] While the forgoing is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof.

Claims

1. 1. A substrate support for use in a chemical vapor deposition (CVD) chamber, comprising: a pedestal for supporting a substrate, the pedestal including a dielectric plate connected to a pedestal body; a rotary union connected to the pedestal, the rotary union including a stationary housing disposed about a rotor; a drive assembly connected to the rotary union and configured to rotate the rotor and thus the pedestal; a coolant union connected to the rotary union and having a coolant inlet fluidly connected via a coolant line to a coolant channel disposed within the pedestal; an RF rotary joint having an RF connector connected to the coolant union and configured to connect the pedestal to an RF bias power source; an RF conduit extending from the RF connector through a central opening in the pedestal body to the pedestal for providing an RF bias to the pedestal; A substrate support comprising:

2. The substrate support of claim 1 , wherein the dielectric plate includes a monopolar electrode, and the RF conduit extends to the monopolar electrode.

3. The substrate support of claim 1 , wherein the RF conduit is a metal rod that extends through the coolant union and the rotary union.

4. The substrate support of claim 1 , further comprising an insulator tube disposed around the RF conduit.

5. The substrate support of claim 4 , further comprising a ground tube disposed around the insulator tube and extending from the RF rotary joint towards the pedestal.

6. The substrate support of claim 1 , wherein the dielectric plate includes one or more chuck electrodes disposed within the dielectric plate.

7. 7. The substrate support of claim 6, wherein the RF conduit comprises a metal tube having a central opening, and further comprising two DC conduits extending from the RF rotary joint through the central opening of the metal tube to the one or more chuck electrodes for supplying DC power to the one or more chuck electrodes.

8. The substrate support of claim 7 , wherein the RF rotary joint comprises a purge gas inlet fluidly connected to the central opening of the metal tube and configured to purge the central opening with a purge gas.

9. The substrate support of claim 1 , wherein the rotary union includes a backside gas inlet, and the substrate support includes a backside gas line extending from the backside gas inlet to an upper surface of the pedestal.

10. 10. The substrate support of claim 1, further comprising: a bellows assembly disposed about the pedestal body; and a lift assembly connected to the bellows assembly and configured to selectively raise or lower the pedestal within a processing chamber.

11. The substrate support of claim 1 , further comprising one or more lift pins extending through the pedestal and configured to lift the substrate off an upper surface of the pedestal.

12. The substrate support of claim 1 , wherein the pedestal comprises a monopolar or bipolar electrode.

13. Substrate support according to any one of claims 1 to 9, wherein the RF rotary joint comprises a fibre optic rotary joint.

14. The substrate support of claim 1 , wherein the pedestal further comprises an insulator plate disposed between the dielectric plate and the pedestal body.

15. 1. A chemical vapor deposition (CVD) processing chamber comprising: a chamber body defining an interior space; a showerhead disposed in the interior space for supplying one or more process gases to the interior space; A substrate support according to any one of claims 1 to 9, arranged in the interior space opposite the showerhead; 1. A CVD processing chamber comprising:

16. 16. The CVD processing chamber of claim 15, wherein the dielectric plate includes one or more chuck electrodes disposed within the dielectric plate, and further including a DC power supply connected to the one or more chuck electrodes for providing DC power to the one or more chuck electrodes.

17. 16. A twin CVD processing chamber comprising two of the CVD processing chambers of claim 15, the twin CVD processing chamber having a single gas flow controller for supplying one or more process gases to each of the two CVD processing chambers.

18. 16. The CVD processing chamber of claim 15, wherein the coolant lines are disposed radially outward of the RF conduits.

19. 16. The CVD processing chamber of claim 15, further comprising a lift assembly connected to the pedestal and configured to selectively raise or lower the pedestal within the interior volume.

20. 20. The CVD processing chamber of claim 19, further comprising one or more lift pins extending through the pedestal, the one or more lift pins including a wider upper portion, a wider lower portion, and a narrow center portion.

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