High temperature detachable very high frequency (VHF) electrostatic chuck (ESC) for pvd chamber

Abstract

This document provides embodiments of a substrate support for use in a substrate processing chamber. In some embodiments, a substrate support includes: an upper assembly having a base plate assembly coupled to a lower surface of a cooling plate, wherein the base plate assembly includes a plurality of electrical feeds, and wherein the cooling plate includes a plurality of openings aligned with the plurality of electrical feeds; an electrostatic chuck disposed on the upper assembly and removably coupled to the cooling plate, wherein the electrostatic chuck has clamping electrodes disposed therein for a first pair of electrical feeds electrically coupled to the plurality of electrical feeds; and an inner tube coupled to the cooling plate and configured to provide an RF delivery path to the electrostatic chuck.

Description

[Technical Field]

[0001] The embodiments disclosed herein are largely related to substrate processing equipment. [Previous Technology]

[0002] Substrate supports are used to provide support for substrates within a substrate processing system, such as a plasma processing chamber. One type of substrate support includes an electrostatic chuck (ESC) coupled to a lower assembly. The ESC generally comprises one or more electrodes embedded in a ceramic chuck body to hold the substrate. The ESC can be removed from the lower assembly to reduce preventative maintenance time and lower replacement costs. However, in combination with higher temperatures (>400 degrees Celsius), conventional ESCs are known to be inefficient at RF frequencies of approximately 60 MHz. At this frequency and temperature, the ESC has high impedance, which prevents effective RF delivery through the ESC and results in lower throughput.

[0003] Thus, the inventors have provided an improved substrate support for high RF frequencies. [Summary of the Invention]

[0004] This document provides embodiments of a substrate support for a substrate processing chamber. In some embodiments, a substrate support for a substrate processing chamber includes: an upper assembly having a base plate assembly coupled to a lower surface of a cooling plate, wherein the base plate assembly includes a plurality of electrical feeds, and wherein the cooling plate includes a plurality of openings aligned with the plurality of electrical feeds; an electrostatic chuck disposed on the upper assembly and removably coupled to the cooling plate, wherein the electrostatic chuck has clamping electrodes disposed therein for a first pair of electrical feeds electrically coupled to the plurality of electrical feeds; and an inner tube coupled to the cooling plate and configured to provide an RF delivery path to the electrostatic chuck via at least one of the following: a gap between the electrostatic chuck and the cooling plate, or metallization of the back side of the electrostatic chuck.

[0005] In some embodiments, a substrate support for a substrate processing chamber includes: an upper assembly having a base plate assembly coupled to a cooling plate, wherein the base plate assembly includes a plurality of electrical feeds disposed around a back-side gas opening, and wherein the cooling plate includes a plurality of openings aligned with the plurality of electrical feeds; an electrostatic chuck disposed on the upper assembly and removably coupled to the cooling plate, wherein the electrostatic chuck has electrodes disposed therein that are electrically coupled to a first pair of electrical feeds; an inner tube coupled to the cooling plate and configured to provide an RF delivery path to the electrostatic chuck via at least one of: a gap between the electrostatic chuck and the cooling plate, or back-side metallization of the electrostatic chuck; and a first resistive heater embedded in the electrostatic chuck and electrically coupled to a second pair of electrical feeds.

[0006] In some embodiments, a processing chamber includes: a chamber body having a substrate support disposed within an internal volume of the chamber body, wherein the substrate support includes: an upper assembly having a base plate assembly coupled to a cooling plate, wherein the base plate assembly includes a plurality of electrical feeds disposed around a back-side gas opening, and wherein the cooling plate includes a plurality of openings aligned with the plurality of electrical feeds; an electrostatic chuck disposed on the upper assembly and removably coupled to the cooling plate, wherein the electrostatic chuck has electrodes disposed therein that are electrically coupled to a first pair of electrical feeds; and a support assembly having an inner tube coupled to the cooling plate and configured to provide an RF delivery path to the electrostatic chuck via at least one of: a gap between the electrostatic chuck and the cooling plate, or back-side metallization of the electrostatic chuck.

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

Implementation Method

[0019] This document provides an embodiment of a removable electrostatic chuck (ESC) for a physical vapor deposition (PVD) chamber operating at extremely high RF frequencies. The extremely high RF frequencies may be, for example, about 40 MHz or greater, or about 60 MHz or greater. The inventors have found that PVD chambers operating at extremely high frequencies can advantageously reduce the resistivity of the films deposited therein. The ESC can also operate at high temperatures (about 400 degrees Celsius or greater).

[0020] Figure 1 depicts a schematic side view of a processing chamber 100 with a substrate support according to at least some embodiments of the present disclosure. In some embodiments, the processing chamber 100 is a PVD chamber. However, other types of processing chambers configured for different processes can also be used or modified for use with the embodiments of the electrostatic chuck described herein.

[0021] The processing chamber 100 is a vacuum chamber suitably configured to maintain a subatmospheric pressure within its internal volume 120 during substrate processing. The processing chamber 100 includes a chamber body 106 covered by a cover 104 that encloses a processing volume 119 located in the upper portion of the internal volume 120. The processing chamber 100 may also include processing shields 105 externally connected to the various chamber components to prevent unwanted reactions between such components and the ionized processing material. The chamber body 106 and the cover 104 may be made of metal, such as aluminum. The chamber body 106 may be grounded via coupling to a ground 115.

[0022] A substrate support 124 is disposed within an internal volume 120 to support and hold a substrate 122, such as a semiconductor wafer, for example, or other such substrates that can be electrostatically held. The substrate support 124 may be substantially contained within an electrostatic chuck 150 disposed on a base 136. The electrostatic chuck 150 may be made of a ceramic material. The base 136 is coupled to a support assembly 103 for supporting the base 136 and the electrostatic chuck 150.

[0023] The support assembly 103 generally includes a hollow inner tube 112 and a bellows assembly 110 disposed around the inner tube 112. The inner tube 112 is configured to provide an RF delivery path from the RF bias power supply 117 to the electrostatic chuck 150. The inner tube 112 also provides conduits for supplying, for example, backside gas, process gas, fluid, coolant, power, an auto capacitive tuner (ACT), or the like, to the electrostatic chuck 150. The bellows assembly 110 may include an outer tube 114 disposed around the inner tube 112. In some embodiments, the outer tube 114 is configured to provide an RF return path from the base 136. In some embodiments, the lower end of the inner tube 112 may protrude beyond the lower end of the outer tube 114 to facilitate electrical connection between the inner tube 112 and the outer tube 114.

[0024] The electrostatic chuck 150 includes one or more clamping electrodes 154 disposed therein. The temperature of the electrostatic chuck 150 can be adjusted to control the temperature of the substrate 122. For example, the electrostatic chuck 150 can be heated using one or more embedded heating elements (e.g., see Figure 5), such as resistance heaters. In some embodiments, the thickness of the electrostatic chuck 150 may be about 6.0 mm or less.

[0025] In some embodiments, the inner tube 112 is coupled to a lifting mechanism 113, such as an actuator or motor, which provides vertical movement of the electrostatic chuck 150 between an upper processing position (as shown in Figure 1) and a lower transfer position (not shown).

[0026] The bellows assembly 110 is coupled between the electrostatic chuck 150 and the bottom surface 126 of the processing chamber 100 to provide a flexible seal that allows vertical movement of the electrostatic chuck 150 while preventing vacuum loss from within the processing chamber 100. The bellows assembly 110 may also include a lower bellows flange 164 that contacts an O-ring 165 or other suitable sealing element that contacts the bottom surface 136 to help prevent loss of chamber vacuum. The bellows assembly 110 may facilitate or partially define the RF return path from the lower assembly 220.

[0027] The inner tube 112 provides conduits for coupling the back-side gas supply 141, the clamping power supply 140, and the heater power supply 160 to the electrostatic chuck 150. The back-side gas supply 141 is disposed outside the chamber body 106 and supplies gas to the electrostatic chuck 150 via gas conduit 146 to control the temperature or pressure and / or temperature or pressure distribution on the support surface of the electrostatic chuck 150 during use. In some embodiments, the RF power supply 174 and the RF bias power supply 117 are coupled to the electrostatic chuck 150 via a corresponding RF matching network (RF matching network 116 is shown only). In some embodiments, the substrate support 124 may alternatively include AC, DC, or RF bias power.

[0028] The RF delivery path and RF return path are arranged coaxially along the support assembly 103. For example, the RF delivery path extends along an inner tube 112 that serves as an RF electrode. The inner tube 112 can be maintained at a constant temperature. The RF return path extends along an outer tube 114 disposed around the inner tube 112. The arrangement of the inner tube 112 and the outer tube 114 creates a neutral or field-free region within the inner tube 112, reducing RF losses due to RF coupling caused by electrostatic chuck wiring, heater wiring, thermocouple wiring, and the like.

[0029] The substrate lifting member 130 may include a lifting pin 109 mounted on a platform 108 connected to a shaft 111, which is coupled to a second lifting mechanism 132 for raising and lowering the substrate lifting member 130, such that the substrate 122 can be placed on or removed from an electrostatic chuck 150. The electrostatic chuck 150 may include a through-hole to receive the lifting pin 109. A bellows assembly 131 is coupled between the substrate lifting member 130 and the bottom surface 126 to provide a flexible seal that maintains a vacuum in the processing chamber during vertical movement of the substrate lifting member 130.

[0030] Processing chamber 100 is coupled to and in fluid communication with vacuum system 184, which includes a throttle valve (not shown) and a vacuum pump (not shown) for evacuating processing chamber 100. The pressure inside processing chamber 100 can be adjusted by regulating the throttle valve and / or the vacuum pump. Processing chamber 100 is also coupled to and in fluid communication with processing gas supplier 118, which supplies one or more processing gases to processing chamber 100 for processing substrate 122 disposed therein.

[0031] Target 138 is disposed opposite to substrate support 124 in processing volume 119 to at least partially define the processing volume therebetween. Target 138 includes a cathode surface defined by the processing volume of the surface facing target 138. Substrate support 124 has a support surface having a plane substantially parallel to the sputtering surface of target 138. Target 138 is connected to one or both of DC power supply 190 and / or RF power supply 174. DC power supply 190 can apply a bias voltage to target 138 relative to processing shield 105.

[0032] The target 138 includes a sputtering plate 142 mounted to a backing plate 144. The sputtering plate 142 contains material to be sputtered onto the substrate 122. The backing plate 144 is made of a metal, such as, for example, stainless steel, aluminum, copper-chromium, or copper-zinc. The backing plate 144 may be made of a material with sufficiently high thermal conductivity to dissipate the heat generated in the target 138, which is formed by eddies generated in the sputtering plate 142 and the backing plate 144, and also by the bombardment of the sputtering plate 142 by high-energy ions from the generated plasma.

[0033] In some embodiments, the processing chamber 100 includes a magnetic field generator 156 for forming a magnetic field around the target 138 to improve sputtering of the target 138. Capacitor-generated plasma can be enhanced by the magnetic field generator 156, wherein, for example, a plurality of magnets 151 (e.g., permanent magnets or electromagnetic coils) can provide a magnetic field in the processing chamber 100 having a rotating magnetic field having an axis of rotation perpendicular to the plane of the substrate 122. The magnetic field generator 156 may include a motor assembly for rotating the plurality of magnets 151. The magnetic field generator 156 can generate a magnetic field near the target 138 to increase the ion density in the processing volume 119 for improving sputtering of the target material. The plurality of magnets 151 can be disposed in a cavity 153 in the cover 104. A coolant (such as water) can be disposed in or circulated through the cavity 153 to cool the target 138.

[0034] The processing chamber 100 includes a processing sleeve 102 external to each chamber component to prevent unwanted reactions between such components and the ionized processing material. The processing sleeve 102 includes a processing shield 105 surrounding the substrate support 124 and the target 138 to at least partially define the processing volume 119. For example, the processing shield 105 may define the outer boundary of the processing volume 119. In some embodiments, the processing shield 105 is made of a metal, such as aluminum.

[0035] In some embodiments, the processing assembly 102 includes a deposition ring 170 resting on the outer edge of the electrostatic chuck 150. In some embodiments, the processing assembly 102 includes a cover ring 180 disposed on the processing shield 105 to form a tortuous airflow path therebetween. In some embodiments, in the processing position, the radially inward of the cover ring 180 rests on the deposition ring 170 to reduce or prevent plasma leakage therebetween.

[0036] In some embodiments, a plurality of grounding loops 172 are provided between the processing shield 105 and the base 136. The grounding loops 172 may generally comprise loops of conductive material, or alternatively, loops of conductive strips, spring members, or the like, configured to ground the processing shield 105 to the base 136 when the substrate support 124 is in the processing position. In some embodiments, the plurality of grounding loops 172 are coupled to the outer lip of the base 136 such that, in the processing position, the grounding loops 172 contact the processing shield 105 to ground the processing shield 105. In some embodiments, in the transfer position, the grounding loops 172 are spaced apart from the processing shield 105.

[0037] Processing chamber 100 is coupled to and in fluid communication with vacuum system 19, which includes a throttle valve (not shown) and a vacuum pump (not shown) for evacuating processing chamber 100. The pressure inside processing chamber 100 can be adjusted by regulating the throttle valve and / or the vacuum pump. Processing chamber 100 is also coupled to and in fluid communication with processing gas supplier 118, which supplies one or more processing gases to processing chamber 100 for processing substrate 122 disposed therein. Slit valve 148 is coupled to chamber body 106 and aligned with an opening in the side wall of chamber body 106 to facilitate the transfer of substrate 122 in and out of chamber body 106.

[0038] In use, when the DC power supply 190 supplies power to the target 138 and other chamber components connected to the DC power supply 190, the RF power supply 174 excites sputtering gas (e.g., from the process gas supply 118) to form a plasma of the sputtering gas. The formed plasma impacts and bombards the sputtering surface of the target 138 to sputter material from the target 138 onto the substrate 122. In some embodiments, the frequency of the RF energy supplied by the RF power supply 174 may vary from about 2 MHz to about 60 MHz or higher. In some embodiments, a plurality of RF power supplies (i.e., two or more) may be provided to provide RF energy at more than a plurality of frequencies. Additional RF power supplies (e.g., RF bias power supply 117) may also be used to supply bias to the substrate support 124 to attract ions from the plasma toward the substrate 122. The RF bias power supply 117 can supply RF power in the ultra-high frequency range, for example, about 13 MHz or higher, or about 40 or about 60 MHz or higher.

[0039] Figure 2 depicts a schematic side view of a substrate support 124 according to at least some embodiments of the present disclosure. A base 136 may include an upper assembly 210 and a lower assembly 220. The upper assembly 210 generally includes a base plate assembly 208 coupled to a cooling plate 212. In some embodiments, the base plate assembly 208 includes a plurality of electrical feeds 214 coupled to a base plate 216 and extending through openings in the base plate 216.

[0040] The cooling plate 212 includes a plurality of openings 218 aligned with a plurality of electrical feeds 214. In some embodiments, the plurality of openings 218 are disposed in a central region of the cooling plate 212. In some embodiments, the central region includes a central protrusion 230 extending from a lower surface of the cooling plate 212. In some embodiments, the plurality of electrical feeds 214 are disposed in the central protrusion 230 of the cooling plate 212. In some embodiments, the central protrusion 230 is dish-shaped, and the outer diameter of the central protrusion 230 is substantially similar to the outer diameter of the base plate 216.

[0041] An electrostatic chuck 150 is disposed above the upper assembly 210 and removably coupled to a cooling plate 212. In some embodiments, terminals 222 extend from the lower surface of the electrostatic chuck 150, which is opposite to and aligned with each of the plurality of electrical feeds 214, to electrically couple each of the electrical feeds 214 to electronic components disposed in the electrostatic chuck 150 (e.g., clamping electrode 154, heater element 508, or the like). In some embodiments, a flexible connector 228 is disposed in each of the plurality of openings 218 and configured to couple each terminal 222 to each corresponding electrical feed of the plurality of electrical feeds 214. The flexible connector 228 is configured to maintain the electrical connection between the terminals 222 and the plurality of electrical feeds 214 during thermal expansion and / or contraction between the upper assembly 210 and the electrostatic chuck 150. The flexible connector 228 may include a first end 830 (see Figure 8) and a second end 832, the first end having a first opening facing the electrostatic chuck 150 to receive one of the terminals 222, and the second end having a second opening at a second end facing the substrate 216 to receive a conductive core of one of a plurality of electrical feeds 214.

[0042] In some embodiments, the electrostatic chuck 150 includes five terminals 222 and the substrate assembly 208 includes five of a plurality of electrical feeds 214, two or a first pair for electrically coupling one or more clamping electrodes 154, two or a second pair for a single-zone heater, and a center tab configured to measure the floating voltage of the substrate 122 when a voltage is applied (e.g., when a bias or voltage from an RF power supply to an ACT is applied). In some embodiments, the electrostatic chuck 150 includes seven terminals 222, two for one or more clamping electrodes 154, four for a dual-zone heater, and one for a center tab. The electrostatic chuck 150 and the upper assembly 210 may be configured to accommodate more or fewer terminals 222 than five to seven. In some embodiments, the central region 232 of the electrostatic chuck 150 includes an interface ring 236 extending from its lower surface. The terminals 222 may be arranged radially outward around the interface ring 236. In some embodiments, terminal 222 extends into a corresponding opening in a plurality of openings 218 in cooling plate 212.

[0043] Figure 5 depicts a close-up cross-sectional side view of the upper portion 500 of the substrate support 124 according to at least some embodiments of the present disclosure. One or more heater elements 508 may be disposed in the electrostatic chuck 150 to heat the electrostatic chuck 150 along one or more heating zones. One or more heater elements 508 are coupled to a heater power supply 160. In some embodiments, a gap 510 is disposed between the electrostatic chuck 150 and the cooling plate 212 to advantageously minimize heat transfer between the electrostatic chuck 150 and the cooling plate 212.

[0044] In use, the gap 510 is evacuated via, for example, a vacuum system 184 to create a vacuum gap. The gap 510 is large enough to minimize contact heat transfer, while small enough to allow RF coupling from the cooling plate 212 to the electrostatic chuck 150 through the gap 510. In some embodiments, the gap 510 is about 0.002 to about 0.006 inches. In some embodiments, the cooling plate 212 includes a plurality of minimum contact area (MCA) pads 506 to support the electrostatic chuck 150. In some embodiments, the plurality of MCA pads 506 comprises about 5 to about 15 MCA pads. In some embodiments, the MCA pads 506 are arranged along two or more concentric circles. For example, in some embodiments, the MCA pads 506 comprise 3 pads along an inner concentric circle and 6 pads along an outer concentric circle. In some embodiments, the MCA pads 506 are arranged at regular intervals. In some embodiments, at least some of the MCA pads 506 are aligned along a common radius of the cooling plate 212.

[0045] Figure 6 depicts the interface between an electrostatic chuck 150 and a cooling plate 212 according to at least some embodiments of the present disclosure. The electrostatic chuck 150 is removably coupled from the cooling plate 212 to enhance replaceability and ease of cleaning. In some embodiments, the electrostatic chuck 150 is coupled to the cooling plate 212 at a central region 232 such that a lower surface 512 of the electrostatic chuck 150 is spaced apart from an upper surface 518 of the cooling plate 212. In some embodiments, the electrostatic chuck 150 is coupled to the cooling plate 212 via a fastener 602 that extends through a central through-hole 632 in the central region 232 of the electrostatic chuck 150 and into the cooling plate 212. In some embodiments, the central through-hole 632 includes a wedge-shaped portion 634 for supporting the head of the fastener 602.

[0046] In some embodiments, fastener 602 secures the electrostatic chuck 150 to the cooling plate 212. In some embodiments, the cooling plate 212 includes a cavity 608 formed in the bottom surface of a central recess 314. In some embodiments, a nut plate 606 is disposed in the cavity 608. In some embodiments, fastener 602 extends through nut plate 606 and the external threads of fastener 602 engage with threaded openings 610 in the cooling plate 212 to couple the electrostatic chuck 150 to the cooling plate 212.

[0047] To remove the electrostatic chuck 150 from the cooling plate 212, fastener 602 can be removed. In some embodiments, to disengage the electrical contacts between the electrostatic chuck 150 and the base plate assembly 208, the nut plate 606 includes external threads of an engagement tool (not shown) for upward lifting of the internal threads 612 of the nut plate 606. When the nut plate 606 is lifted, it pushes against the electrostatic chuck 150 and disengages from all electrical contacts. In some embodiments, when the cooling plate 212 includes the MCA pad 506, the interface ring 236 of the electrostatic chuck 150 may be spaced apart from the wall of the central recess 314 and the nut plate 606. In some embodiments, when the cooling plate 212 does not include the MCA pad 506, the nut plate 606 may provide a contact area only between the electrostatic chuck 150 and the cooling plate 212, thereby advantageously minimizing thermal coupling. In some embodiments, the nut plate 606 may contact the interface ring 236 to support the central region 232 of the electrostatic chuck 150 and the MCA pad 506 may support the peripheral region of the electrostatic chuck 150.

[0048] In some embodiments, the central through-hole 632 is coupled to a gas conduit 146 for supplying back-side gas from the back-side gas supplier 141 to the upper surface of the electrostatic chuck 150. In some embodiments, the fastener 602 includes a gas passage 638 disposed therethrough for providing a flow path for the back-side gas to the upper surface of the electrostatic chuck 150. A gas plug (not shown) may be disposed in the central through-hole 632 above the fastener 602.

[0049] Figure 7A depicts a back-side metallization pattern on the back side of an electrostatic chuck 150 according to at least some embodiments of the present disclosure. Figure 7B depicts a schematic side view of an electrostatic chuck 150 having a back-side metallization pattern according to at least some embodiments of the present disclosure. In some embodiments, RF is coupled from a cooling plate 212 to the electrostatic chuck 150 via a back-side metallization 702, which physically contacts the cooling plate 212 to provide RF coupling. The back-side metallization 702 eliminates the need for a gap 510 and improves RF delivery. The back-side metallization 702 may contain any suitable metal for RF coupling.

[0050] In some embodiments, one or more RF contacts 720 may be disposed between the back metallization 702 and the cooling plate 212, such that the RF delivery path extends from one or more RF contacts 720 to the back metallization 702 and the back metallization 702 does not contact the cooling plate 212 at all, thereby reducing thermal coupling. In some embodiments, one or more RF contacts are disposed along the ring 710. The back metallization 702 may comprise any suitable pattern disposed on the lower surface 512 of the electrostatic chuck 150. For example, the back metallization 702 may comprise a plurality of branches 718 extending from the central region 232 to the outer region 730 or outer surface 732 of the electrostatic chuck 150. In some embodiments, the plurality of branches 718 extend in a non-linear manner. In some embodiments, second plurality of branches 728 are disposed between the plurality of branches 718 in the outer region 730. In some embodiments, each plurality of branches 718 and each second plurality of branches 728 has one or more RF contacts 720.

[0051] Returning to Figure 2, the support assembly 103 includes an inner tube 112 coupled to a cooling plate 212 and configured to provide an RF delivery path to the electrostatic chuck 150 via at least one of the following: a gap 510 between the electrostatic chuck 150 and the cooling plate 212 or a back-side metallization 702 of the electrostatic chuck 150. A gas conduit 146 extends through the inner tube 112. In some embodiments, a back-side gas supply 141 is fluidly coupled to the lower surface 512 of the electrostatic chuck 150 via the following: a gas conduit 146 of the base plate assembly 208, a gas opening 268 through the cooling plate 212, and a central through-hole 632 of the electrostatic chuck 150. In some embodiments, a temperature measuring device 266 extends through the inner tube 112. In some embodiments, the temperature measuring device 266 extends through the base plate 216 and through the cooling plate 212 into the electrostatic chuck 150. In some embodiments, the temperature measuring device 266 extends into the interface ring 236 of the electrostatic chuck 150. In some embodiments, the temperature measuring device 266 extends through the central protrusion 230 of the cooling plate 212. The temperature measuring device 266 may be a thermocouple, an optical temperature measuring device, or the like.

[0052] In some embodiments, the lower assembly 220 of the base 136 includes a ceramic block 224 disposed on a housing 226 of the lower assembly 220. In some embodiments, the housing 226 includes an outer lip 246 surrounding the ceramic block 224. In some embodiments, the housing 226 includes an outer wedge 248 extending radially outward from the outer lip 246. The outer wedge 248 may provide coupling surfaces for a plurality of grounding loops 172. The housing 226 is coupled to the outer tube 114. In some embodiments, the housing 226 is disposed on a bellows weldment 258 coupled to the bellows assembly 110.

[0053] In some embodiments, the cooling plate 212 includes a coolant channel 240 for circulating cooling therein to control the temperature of the electrostatic chuck 150. A coolant supply line 242 may extend from the coolant supplier 280 to the coolant channel 240. In some embodiments, the coolant supply line 242 extends through the inner tube 112. The cooling plate 212 is discussed in more detail below with reference to Figures 3 and 4.

[0054] In some embodiments, the lower assembly 220 of the base 136 includes an RF delivery tray 250 coupled at its lower end to the inner tube 112 and at its upper end to the cooling plate 212. In some embodiments, the RF delivery tray 250 has a bowl-shaped form extending from the inner tube 112 toward the ceramic block 224. In some embodiments, a central protrusion 230 of the base plate 216 and the cooling plate 212 may be disposed within the RF delivery tray 250. In some embodiments, the RF delivery tray 250 includes an outer lip 252 extending radially outward from the upper portion of the RF delivery tray 250. In some embodiments, the outer lip 252 is disposed between the cooling plate 212 and the ceramic block 224. In some embodiments, the lower assembly 220 includes a base plate 216 coupled within the RF delivery tray 250 and a cover plate 254 configured to cover a plurality of electrical feedthroughs 214. In some embodiments, the cover plate 254 is made of a polymer material.

[0055] In some embodiments, the RF delivery path extends from the inner tube 112 to the RF delivery tray 250 to the outer surface of the cooling plate 212 to the upper surface 518 of the cooling plate 212 and to the electrostatic chuck 150. In some embodiments, the RF return path extends from the processing volume 119 to the upper surface of the housing 226 to the outer tube 114. The ceramic block 224 is configured to electrically isolate the RF delivery path from the RF return path. In some embodiments, the housing 226 is made of metal, such as aluminum. In some embodiments, the inner tube 112 is made of metal, such as aluminum.

[0056] Figure 3 depicts an isometric top view of a cooling plate 212 according to at least some embodiments of the present disclosure. In some embodiments, the cooling plate 212 is made of stainless steel or aluminum. In some embodiments, the upper surface 518 of the cooling plate 212 has a varying emissivity depending on the need to control heat loss. For example, the upper surface 518 may have a higher emissivity at the central portion 310 compared to the peripheral portion 320 to further help control the temperature uniformity across the electrostatic chuck 150. The higher emissivity can be achieved via any suitable process, such as by machining, sanding, anodizing, or the like.

[0057] The cooling plate 212 may include a plurality of radial channels 304 on its upper surface 518 to help evacuate air disposed between the cooling plate 212 and the electrostatic chuck 150 to create a vacuum therebetween. In some embodiments, the upper surface 518 includes a central recess 314 to receive the interface ring 236 of the electrostatic chuck 150. In some embodiments, one radial channel 304A of the plurality of radial channels 304 may extend into the central recess 314 to help evacuate air disposed between the interface ring 236 and the cooling plate 212. In some embodiments, the plurality of radial channels 304 includes six channels. In some embodiments, the plurality of radial channels 304 extend through openings 218 of the plurality of electrical feedthroughs 214. The cooling plate 212 may include an opening 306 to receive a lifting pin 109.

[0058] Figure 4 depicts an isometric bottom view of a cooling plate 212 according to at least some embodiments of the present disclosure. In some embodiments, the lower surface 402 of the cooling plate 212 includes a central protrusion 230 and a coolant channel 240 disposed around the central protrusion 230. The coolant channel 240 may extend along any suitable path for cooling the cooling plate 212. In some embodiments, the coolant channel 240 extends in a wavy or non-circular manner. In some embodiments, the coolant channel 240 includes an inlet 420 and an outlet 422. In some embodiments, the cooling plate 212 includes one or more alignment features 412 for aligning the cooling plate 212 with the base plate 216. In some embodiments, the central protrusion 230 includes an opening 406 for a temperature measuring device 266. In some embodiments, a gas opening 268 through the cooling plate 212 may include one or more bends to provide sufficient separation between the gas opening 268 and the temperature measuring device 266. An O-ring groove 430 may be disposed around the gas opening 268 to seal the gas opening 268.

[0059] Figure 8 depicts an isometric top view of a base plate assembly 208 according to at least some embodiments of the present disclosure. In some embodiments, a base plate 216 of the base plate assembly 208 includes a plurality of fastener openings 810 for coupling the base plate 216 to a cooling plate 212. The base plate 216 includes a gas opening 812 coupled to a gas conduit 146. The gas opening 812 is aligned with a gas opening 268 of the cooling plate 212. In some embodiments, a plurality of electrical feedthroughs 214 may be disposed near the outer surface of the base plate 216. O-ring grooves 818 may be disposed around each of the plurality of electrical feedthroughs 214 to seal the plurality of openings 218 of the cooling plate 212. O-ring grooves 806 may be disposed around a temperature measuring device 266. Figure 8 depicts a flexible connector 228. In some embodiments, the flexible connector 228 includes a plurality of slits 834 for allowing a first end 830 to move relative to a second end 832.

[0060] Although the foregoing relates to embodiments of the present disclosure, other and further embodiments of the present disclosure may be designed without departing from its basic scope. [Simplified Explanation of the Diagram]

[0008] The embodiments of this disclosure, which have been briefly summarized above and discussed in more detail below, can be understood by referring to the illustrative embodiments of this disclosure depicted in the accompanying drawings. However, the drawings only show typical embodiments of this disclosure and are therefore not to be considered as limiting the scope, as this disclosure may allow for other equivalent and effective embodiments.

[0009] Figure 1 depicts a schematic side view of a processing chamber with a substrate support according to at least some embodiments of the present disclosure.

[0010] Figure 2 depicts a schematic side view of a substrate support according to at least some embodiments of the present disclosure.

[0011] Figure 3 depicts an isometric top view of a cooling plate according to at least some embodiments of the present disclosure.

[0012] Figure 4 depicts an isometric bottom view of a cooling plate according to at least some embodiments of the present disclosure.

[0013] Figure 5 depicts a close-up cross-sectional side view of the upper part of a substrate support according to at least some embodiments of the present disclosure.

[0014] Figure 6 depicts the interface between an electrostatic chuck and a cooling plate according to at least some embodiments of the present disclosure.

[0015] Figure 7A depicts a back-side metallization pattern on the back side of an electrostatic chuck according to at least some embodiments of the present disclosure.

[0016] Figure 7B depicts a schematic side view of an electrostatic chuck with a back-side metallized pattern according to at least some embodiments of the present disclosure.

[0017] Figure 8 depicts an isometric top view of a base plate according to at least some embodiments of the present disclosure.

[0018] For ease of understanding, the same element symbols have been used to identify common elements in the figures where possible. The figures 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. [Biomaterial Storage]

[0062] Domestic storage information (please note in order of storage institution, date, and number): None. International storage information (please note in order of storage country, institution, date, and number): None.

Claims

1. A substrate support for a substrate processing chamber, comprising: an upper assembly having a base plate assembly coupled to a lower surface of a cooling plate, wherein the base plate assembly includes a plurality of electrical feeds, and wherein the cooling plate includes a plurality of openings aligned with the plurality of electrical feeds; an electrostatic chuck disposed on the upper assembly and removably coupled to the cooling plate, wherein the electrostatic chuck has a clamping electrode disposed therein and electrically coupled to a first pair of electrical feeds; and an inner tube coupled to the cooling plate and configured to provide an RF delivery path to the electrostatic chuck via at least one of: a gap between the electrostatic chuck and the cooling plate, or back-side metallization of the electrostatic chuck; wherein at least one of the following is present: The electrostatic chuck is coupled to the cooling plate at a central region such that a lower surface of the electrostatic chuck is separated from an upper surface of the cooling plate, or further includes an outer tube disposed around the inner tube and a lower assembly having a ceramic block disposed on a housing, wherein the outer tube is coupled to the housing to provide an RF return path, and wherein the ceramic block is disposed between the housing and the cooling plate to isolate the RF delivery path from the RF return path, or the electrostatic chuck has an interface ring extending from a lower surface of the electrostatic chuck, wherein the interface ring includes a A central through-hole, fluidly coupled to an opening in the cooling plate and configured to allow backside gas to flow through, or a thermocouple configured to pass through a central protrusion of the cooling plate and extend into the electrostatic chuck, or further comprising a flexible connector including an opening at a first end to receive a terminal extending from a lower surface of the electrostatic chuck and an opening at a second end to receive a conductive core of one of the plurality of electrical feeds, or wherein the lower surface of the cooling plate includes a central protrusion and a coolant channel disposed around the central protrusion.

2. The substrate support as claimed in claim 1, wherein the electrostatic chuck is coupled to the cooling plate at the central region of the electrostatic chuck, such that the lower surface of the electrostatic chuck is spaced apart from the upper surface of the cooling plate.

3. The substrate support as claimed in claim 1, wherein the outer tube is disposed around the inner tube; and the lower assembly has the ceramic block disposed on the housing, wherein the outer tube is coupled to the housing to provide the RF return path, and wherein the ceramic block is disposed between the housing and the cooling plate to isolate the RF delivery path from the RF return path.

4. The substrate support as claimed in claim 1, wherein the electrostatic chuck has an interface ring extending from the lower surface of the electrostatic chuck, wherein the interface ring includes an opening fluidly coupled to the cooling plate and a central through-hole configured to allow back-side gas to flow through it.

5. The substrate support as claimed in claim 1, wherein the cooling plate is made of stainless steel or aluminum.

6. The substrate support as claimed in claim 1, wherein the thermocouple is disposed through the central protrusion of the cooling plate and extends into the electrostatic chuck.

7. The substrate support as claimed in claim 1, wherein the flexible connector includes an opening at the first end for receiving the terminal extending from the lower surface of the electrostatic chuck and an opening at the second end for receiving the conductive core of one of the plurality of electrical feeds.

8. The substrate support as claimed in claim 1, wherein the lower surface of the cooling plate includes the central protrusion and the coolant channel disposed around the central protrusion.

9. The substrate support as claimed in claim 8, wherein the outer diameter of the central protrusion is substantially similar to the outer diameter of the substrate assembly.

10. A substrate support for a substrate processing chamber, comprising: an upper assembly having a base plate assembly coupled to a cooling plate, wherein the base plate assembly includes a plurality of electrical feeds disposed around a back-side gas opening, and wherein the cooling plate includes a plurality of openings aligned with the plurality of electrical feeds; an electrostatic chuck disposed on the upper assembly and removably coupled to the cooling plate, wherein the electrostatic chuck has an electrode disposed therein and electrically coupled to a first pair of electrical feeds; an inner tube coupled to the cooling plate and configured to provide an RF delivery path to the electrostatic chuck via at least one of: a gap between the electrostatic chuck and the cooling plate, or back-side metallization of the electrostatic chuck; and a first resistive heater embedded in the electrostatic chuck and electrically coupled to a second electrode of the electrical feeds; wherein at least one of the following is present: Compared to a peripheral portion, an upper surface of the cooling plate has a higher emissivity at a central portion; or a lower surface of the electrostatic chuck includes a metallized pattern to provide RF contact with the cooling plate; or a lower surface of the electrostatic chuck includes an interface ring and five terminals disposed around the interface ring and aligned with the plurality of electrical feedthroughs; or the electrostatic chuck is coupled to the cooling plate via a fastener extending through a central region of the electrostatic chuck, wherein the fastener extends through a nut plate and the external thread of the fastener engages with a threaded opening in the cooling plate to couple the electrostatic chuck to the cooling plate.

11. The substrate support as claimed in claim 10, wherein the upper surface of the cooling plate has the higher emissivity at the central portion compared to the peripheral portion.

12. The substrate support as claimed in claim 10, wherein the lower surface of the electrostatic chuck includes the metallization pattern to provide RF contact with the cooling plate.

13. The substrate support as claimed in claim 10, wherein the lower surface of the electrostatic chuck includes the interface ring and five terminals disposed around the interface ring and aligned with the plurality of electrical feeds.

14. The substrate support as claimed in claim 10, wherein the electrostatic chuck is coupled to the cooling plate via a fastener extending through the central region of the electrostatic chuck, wherein the fastener extends through the nut plate and the external thread of the fastener engages with the threaded opening in the cooling plate to couple the electrostatic chuck to the cooling plate.

15. A processing chamber comprising: a chamber body having a substrate support disposed within an internal volume of the chamber body, wherein the substrate support includes: an upper assembly having a base plate assembly coupled to a cooling plate, wherein the base plate assembly includes a plurality of electrical feeds disposed around a back-side gas opening, and wherein the cooling plate includes a plurality of openings aligned with the plurality of electrical feeds; an electrostatic chuck disposed on the upper assembly and removably coupled to the cooling plate, wherein the electrostatic chuck has an electrode disposed therein and electrically coupled to a first pair of electrical feeds; and a support assembly having an inner tube coupled to the cooling plate and configured to provide an RF delivery path to the electrostatic chuck via at least one of: a gap between the electrostatic chuck and the cooling plate, or back-side metallization of the electrostatic chuck; wherein at least one of the following is present: The device further includes a lower component comprising a ceramic block disposed on a housing, wherein the housing includes an outer lip surrounding the ceramic block; or the plurality of electrical feeds disposed in a central protrusion of the cooling plate; or a flexible connector disposed between the electrostatic chuck and each electrical feed to allow thermal expansion of the electrostatic chuck while maintaining electrical coupling.

16. The processing chamber as claimed in claim 15, wherein the lower assembly includes the ceramic block disposed on the housing, wherein the housing includes the outer lip surrounding the ceramic block.

17. The processing chamber as claimed in claim 16, further comprising a processing shield disposed around the substrate support, wherein a plurality of grounding loops are coupled to the housing and configured to contact the processing shield when the substrate support is in an upper processing position.

18. The processing chamber as claimed in claim 15, wherein the plurality of electrical feeds are disposed in the central protrusion of the cooling plate.

19. The processing chamber as claimed in claim 15 further includes a back-side gas supply fluidly coupled to a lower surface of the electrostatic chuck via a central through-hole of the electrostatic chuck and a gas conduit of the base plate assembly.

20. The processing chamber as claimed in claim 15, wherein the flexible connector is disposed between the electrostatic chuck and each electrical feedthrough to allow thermal expansion of the electrostatic chuck while maintaining electrical coupling.

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