Cooled substrate support assembly for radio frequency environments

Abstract

A substrate support assembly is described herein, including a utility plate, a ground plate coupled to the utility plate, a fluid conduit disposed within the substrate support assembly and disposed through the utility plate and the ground plate, and a connector coupled to the ground plate, the ground plate housing a portion of the fluid conduit. The connector includes a biasing assembly and a fastener disposed in a pocket formed in the ground plate.

Description

TECHNICAL FIELD

[0001] Embodiments of the present disclosure generally relate to semiconductor chamber components, and more specifically to a cooled substrate support assembly for use in high frequency electric fields. BACKGROUND

[0002] For next generation very large scale integration (VLSI) and ultra large scale integration (ULSI) of semiconductor devices, reliably producing nanometer and smaller features is one of the key technical challenges. However, as the circuit technology limits are continually pushed, the size of the VLSI and ULSI interconnect technology is continually shrinking, placing higher demands on the processing capabilities. Reliably forming gate structures on substrates is important to the success of VLSI and ULSI and to the continuing efforts to increase circuit density and quality of individual substrates and dies.

[0003] To reduce manufacturing costs, integrated chip (IC) manufacturers are demanding higher throughput and better device yield and performance from each silicon substrate processed. Some of the manufacturing techniques being explored in current development for next generation devices require processing at low temperatures. Dry reactive ion etching uniformly maintains a substrate at low temperature, enabling ions to bombard a face-up surface of a material disposed on the substrate with reduced spontaneous etching, thereby forming a trench with smooth, vertical sidewalls. Additionally, selectivity of etching one material over another can be improved at low temperatures. For example, selectivity between silicon (Si) and silicon dioxide (SiO2) increases exponentially as temperature is decreased.

[0004] Operating a substrate support assembly to enable low temperature processing typically relies on the use of coolant that is circulated through the substrate support assembly. Because the conduits used to route the coolant across the substrate support assembly are simultaneously grounded and energized, the coolant and the conduits must have sufficient electrical insulation to prevent shorting. However, coolant flow within the insulated conduits can cause electrical charges to build up on the conduits over time that are sufficient to cause an electrical arc between the conduits and a grounded portion of the substrate support assembly. Moreover, cooling and heating of the substrate support assembly causes expansion and contraction that can cause leaks at the conduits. Arcing and / or coolant leaks can cause or result in many problems.

[0005] Therefore, there is a need for improved substrate support assemblies. SUMMARY

[0006] Described herein is a substrate support assembly including one or more fluid conduits for delivering fluid at low temperatures. The fluid conduits are configured to reduce arcing.

[0007] In one embodiment, a substrate support assembly is described herein, comprising: a utility plate; a ground plate coupled to the utility plate; a fluid conduit disposed within the substrate support assembly and disposed through the utility plate and the ground plate; and a connector coupled to the ground plate, the ground plate housing a portion of the fluid conduit. The connector includes a biasing assembly and a fastener disposed in a pocket formed in the ground plate.

[0008] In another embodiment, a substrate support assembly is described, comprising: a base assembly for supporting an electrostatic chuck; a utility plate coupled to the base assembly; a dielectric plate coupled to the utility plate; a ground plate coupled to the utility plate; a fluid conduit disposed within the substrate support assembly and disposed through the utility plate and the ground plate; and a connector coupled to the ground plate, the ground plate housing a portion of the fluid conduit. The connector includes a biasing assembly and a fastener disposed in a pocket formed in the ground plate. A sliding seal surrounds a body of the connector.

[0009] In another embodiment, a substrate support assembly is described herein, comprising: a substrate support assembly is described herein, comprising: a base assembly for supporting an electrostatic chuck; a utility plate coupled to the base assembly; a dielectric plate coupled to the utility plate; a ground plate coupled to the utility plate; a fluid conduit disposed within the substrate support assembly and disposed through the utility plate and the ground plate; and a connector coupled to the ground plate, the ground plate housing a portion of the fluid conduit. The connector includes a biasing assembly and a fastener disposed in a pocket formed in the ground plate. A sliding seal surrounds a body of the connector. BRIEF DESCRIPTION OF DRAWINGS

[0010] So that the manner in which the above-recited features of the present disclosure can be understood in detail, a brief description of the embodiments can be had, by reference to a

[0011] Figure 1 is a cross-sectional schematic view of an exemplary plasma processing chamber according to an embodiment.

[0012] Figure 2 is a schematic cross-sectional view of an exemplary substrate support assembly according to an embodiment.

[0013] Figure 3yes Figure 2 A cross-sectional view of a portion of the substrate support assembly.

[0014] Figure 4 It is an isometric diagram of the connector as disclosed in this article.

[0015] Figure 5 This is a schematic cross-sectional view illustrating one embodiment of a vacuum path through a substrate support assembly as described herein.

[0016] Figure 6A and Figure 6B They are respectively used as having, for example Figure 3 and Figure 5 The cross-sectional view of the upper and lower end guides of the tubular member described herein.

[0017] Figure 7 This is a partial isometric view of one embodiment of a spring seal.

[0018] For ease of understanding, the same reference numerals are used as much as possible to indicate the same elements common in the figures. It is conceivable that elements and features of one embodiment may be advantageously incorporated into other embodiments without further description. Detailed Implementation

[0019] The embodiments described herein provide a substrate support assembly that enables electrostatic chucks (ESCs) to operate at low temperatures, maintaining a substrate disposed thereon at a suitable low-temperature processing temperature while keeping other surfaces of the processing chamber at different temperatures. The low-temperature processing temperature (i.e., substrate temperature) is intended to refer to a temperature below -10 degrees Celsius at the substrate support.

[0020] Although the substrate support assembly is described below as being in an etching process chamber, it can be used in other types of plasma process chambers, such as physical vapor deposition chambers, chemical vapor deposition chambers, ion implantation chambers, and other systems where it is desirable to maintain the processed substrate at a low processing temperature. However, it should be noted that the substrate support assembly and chamber components described herein can be used at other processing temperatures.

[0021] Figure 1is a cross-sectional schematic view of an exemplary plasma processing chamber 100, shown configured as an etch chamber having a substrate support assembly 101. As described above, the substrate support assembly 101 can be used in other types of plasma processing chambers, such as plasma processing chambers, anneal chambers, physical vapor deposition chambers, chemical vapor deposition chambers, and ion implantation chambers, among others, as well as other systems requiring the ability to uniformly maintain a surface of a workpiece (e.g., substrate 124) at a low temperature processing temperature. Dry reactive ion etching maintains the substrate 124 at a low temperature processing temperature enables ions to bombard a top-facing surface of a material disposed on the substrate 124 with reduced spontaneous etching, thereby forming a trench having smooth, vertical sidewalls. For example, as ions continuously bombard a top-facing surface of a low-k dielectric material to form a trench having smooth, vertical sidewalls, diffusion of ions disposed in pores of the low-k dielectric material disposed on the substrate 124 uniformly maintained at a low temperature processing temperature is reduced. Additionally, at a low temperature processing temperature, selectivity of etching one material over another material can be improved. For example, as temperature decreases, selectivity between silicon (Si) and silicon dioxide (SiO2) increases exponentially.

[0022] The plasma processing chamber 100 includes a chamber body 102 having sidewalls 104, a bottom 106, and a lid 108 to enclose a processing region 110. An injection apparatus 112 is coupled to the sidewalls 104 and / or the lid 108 of the chamber body 102. A gas panel 114 is coupled to the injection apparatus 112 to allow process gases to be provided into the processing region 110. The injection apparatus 112 can be one or more nozzles or inlet ports, or alternatively, a showerhead. Process gases, as well as any process byproducts, are removed from the processing region 110 through a drain port 116 formed in the sidewalls 104 or the bottom 106 of the chamber body 102. The drain port 116 is coupled to a pumping system 140, which includes a throttle valve and a pump to control the vacuum level within the processing region 110. The pumping system 140 is also used to remove process byproducts through the drain port 116.

[0023] The process gases can be energized to form a plasma within the processing region 110. The process gases can be energized by capacitively or inductively coupling RF power to the process gases. In one embodiment, which can be combined with other embodiments described herein, a plurality of coils 118 are disposed above the lid 108 of the plasma processing chamber 100 and are coupled to an RF power source 122 through a matching circuit 120, as depicted in FIG. 1. Figure 1

[0024] ​The substrate support assembly 101 is disposed in a processing region 110 below the injection apparatus 112. The substrate support assembly 101 includes an electrostatic chuck (ESC) 103 and an ESC base assembly 105. The ESC base assembly 105 is coupled to the ESC 103 and a facility plate 107. The facility plate 107, which is supported by a ground plate 111, is configured to facilitate electrical, cooling, heating, and gas connections with the substrate support assembly 101. The ground plate 111 is supported by a bottom 106 of the processing chamber. A dielectric plate 109 electrically insulates the facility plate 107 from the ground plate 111.

[0025] The ESC base assembly 105 includes a base channel 115 fluidly coupled to a cryogenic chiller 117. The cryogenic chiller 117 provides a base fluid (such as a refrigerant) to the base channel 115 such that the ESC base assembly 105, and thus the substrate 124, can be maintained at a predetermined cryogenic temperature. Similarly, the facility plate 107 includes a facility channel 113 (further described in detail in Figure 2 ) fluidly coupled to a chiller 119. The chiller 119 provides a facility fluid to the facility channel 113 such that the facility plate 107 is maintained at a predetermined temperature. In one example, the base fluid maintains the ESC base assembly 105 at a temperature that is lower than the temperature of the facility plate 107.

[0026] The ESC 103 has a support surface 130 and a bottom surface 132 opposite the support surface 130. In one embodiment, which can be combined with other embodiments described herein, the ESC 103 is made of a ceramic material, such as aluminum oxide (AI2O3), aluminum nitride (AIN), or other suitable material. Alternatively, the ESC 103 can be made of a polymer, such as polyimide, polyether ether ketone, polyaryletherketone, or the like.

[0027] A bonding layer 133 is provided at the interface between the bottom surface 132 of the ESC 103 and the top surface 134 of the ESC base assembly 105. The ESC 103 and the ESC base assembly 105 are selected from materials having substantially similar coefficients of thermal expansion (CTE). The ESC 103 can be made of aluminum oxide (AI2O3) or aluminum nitride (AIN). The ESC base assembly 105 can be made of aluminum (Al), molybdenum (Mo), ceramic, or combinations of the above. Example materials for the bonding layer 133 include indium (In), Al, silicone (including Si), perfluoropolymers, or combinations and alloys of the above. In one application, an alloy of Mo and Al (about 50% to 40% aluminum) is used for the ESC base assembly 105 with the CTE of the aluminum oxide ESC. Due to the small difference in CTE of the ESC 103 and the ESC base assembly 105 from about 90 degrees Celsius to about -200 degrees Celsius during operation, the bonding layer 133 allows stress to be absorbed. The bonding layer 133 can be mixed with ceramic powder to improve the thermal conductivity that provides improved heat transfer from the ESC 103 and the ESC base assembly 105 via conduction, thereby enhancing the operation of the ESC 103.

[0028] The ESC 103 includes a chucking electrode 126 disposed in the ESC 103. The chucking electrode 126 can be configured as a monopolar or bipolar electrode, or other suitable arrangement. The chucking electrode 126 is coupled through an RF filter and a utility plate 107 to a chucking power source 135 that provides DC power to electrostatically secure the substrate 124 to the support surface 130 of the ESC 103. The RF filter prevents RF power used to form a plasma (not shown) within the plasma processing chamber 100 from damaging electrical equipment or creating an electrical hazard outside of the chamber.

[0029] The ESC 103 includes one or more resistive heaters 128 embedded in the ESC 103. The resistive heaters 128 are used to control the temperature of the ESC 103 cooled by the ESC base assembly 105 so that a low temperature process temperature suitable for processing a substrate 124 disposed on a support surface 130 of the substrate support assembly 101 can be maintained. The resistive heaters 128 are coupled to a heater power source 136 through the facility plate 107 and an RF filter. The RF filter prevents RF power used to form a plasma (not shown) within the plasma processing chamber 100 from damaging electrical equipment or creating an electrical hazard outside of the chamber. The heater power source 136 can provide 500 Watts or more of power to the resistive heaters 128. The heater power source 136 includes a controller (not shown) for controlling the operation of the heater power source 136, which is typically set to heat the substrate 124 to a predetermined low temperature. In one embodiment, which can be combined with other embodiments described herein, the resistive heaters 128 include a plurality of laterally separated heating zones, where the controller enables at least one zone of the resistive heaters 128 to be preferentially heated relative to the resistive heaters 128 located in one or more other zones. For example, the resistive heaters 128 can be arranged concentrically in a plurality of separated heating zones. The resistive heaters 128 maintain the substrate 124 at a low temperature process temperature suitable for processing. In one embodiment, which can be combined with other embodiments described herein, the low temperature process temperature is less than about -10 degrees Celsius. For example, the low temperature process temperature is between about -10 degrees Celsius and about -150 degrees Celsius, including as low as about -200 degrees Celsius.

[0030] The cryogenic cooler 117 is coupled to the substrate inlet conduit 123 via an inlet 254 Figure 2 ) to the substrate channel 115 and is coupled to the substrate outlet conduit 125 via an outlet 256 Figure 2The substrate outlet conduit 125 is in fluid communication with the substrate channel 115, allowing the ESC substrate assembly 105 to be maintained at a predetermined cryogenic temperature. In one embodiment, which may be combined with other embodiments described herein, a cryogenic cooler 117 is coupled to an interface box to control the temperature of the substrate fluid. The substrate fluid includes components that maintain the liquid at a cryogenic temperature below -50 degrees Celsius at operating pressures. The substrate fluid is typically dielectric or electrically insulating, such that no electrical path is formed across the substrate fluid when it circulates through the substrate support assembly 101. Non-limiting examples of suitable substrate fluids include fluorinated heat transfer fluids. The cryogenic cooler 117 provides substrate fluid circulating through the substrate channel 115 of the ESC substrate assembly 105. The substrate fluid flowing through the substrate channel 115 enables the ESC substrate assembly 105 to be maintained at a cryogenic temperature, which helps control the lateral temperature distribution of the ESC 103, allowing the substrate 124 disposed on the ESC 103 to be uniformly maintained at the cryogenic processing temperature. In one embodiment that can be combined with other embodiments described herein, the cryogenic cooler 117 is a single-stage cooler operable to maintain a cryogenic temperature below about -50 degrees Celsius. In another embodiment that can be combined with other embodiments described herein, the cryogenic cooler 117 is a two-stage cooler that utilizes refrigerant within a two-stage cooler to maintain the base fluid at a cryogenic temperature below -50 degrees Celsius.

[0031] Cooler 119 is connected to inlet 240 via facility passage 113. Figure 2 The facility inlet conduit 127 and the outlet 242 connected to the facility passage 113 Figure 2 The facility outlet conduit 129 is in fluid communication with the facility channel 113, allowing the facility plate 107 to be maintained at a predetermined ambient temperature. In one embodiment, which may be combined with other embodiments described herein, the cooler 119 is coupled to an interface box to control the temperature of the facility fluid. The facility fluid may include a material capable of maintaining an ambient temperature between about -10 degrees Celsius and about 60 degrees Celsius. The cooler 119 provides facility fluid circulating through the facility channel 113 of the facility plate 107. The facility fluid is typically dielectric or electrically insulating, such that no electrical path is formed through the facility fluid when circulating through the substrate support assembly 101. Non-limiting examples of suitable facility fluids include fluorinated heat transfer fluids. The facility fluid flowing through the facility channel 113 enables the facility plate 107 to be maintained at a predetermined ambient temperature, which helps to maintain the dielectric plate 109 at a predetermined ambient temperature.

[0032] Figure 2This is a schematic cross-sectional view of an exemplary substrate support assembly 101 according to an embodiment. The substrate support assembly 101 is configured to enable the ESC 103 to operate at low temperatures, such that a substrate 124 disposed thereon is maintained at a low-temperature processing temperature. The ESC 103 is coupled to the ESC base assembly 105. An adsorption electrode 126 is coupled to an adsorption power source 135 via a first insulated wire 204 disposed through a first hole 208 in the lower insulator 212 of the facility plate 107 and the upper insulator 214 of the ESC base assembly 105. One or more resistance heaters 128 are coupled to a heater power source 136 via a second insulated wire 206 disposed through a second hole 210 in the lower insulator 212 of the facility plate 107 and the upper insulator 214 of the ESC base assembly 105. In some embodiments, the ESC base assembly 105 includes an upper plate 215 and a lower plate 217. A thermal insulation 227 is provided between the upper plate 215 and the lower plate 217. The upper plate 215 may be made of Mo, while the lower plate 217 may be made of Al. In one embodiment, which may be combined with other embodiments described herein, the thermal insulation 227 comprises a material containing polyamide-imide (PAI) or polyimide (PI).

[0033] Facility plate 107 includes a plate portion 229 and a wall portion 230. The plate portion 229 of facility plate 107 is coupled to ESC base assembly 105 using one or more first screw assemblies 220, such that a vacuum region 222 exists between ESC base assembly 105 and facility plate 107. Each of the one or more first screw assemblies 220 includes a bolt 224 that contacts facility plate 107 via biasing element 226 and is inserted into a threaded hole 228 in ESC base assembly 105.

[0034] The bias element 226 is used to generate force when compressed. Suitable bias elements 226 include coil springs, spring forming elements, and elastomers. In one example, the bias element 226 is a plurality of Belleville washers. The bias element 226 is compressed by tightening the bolt 224, so that the facility plate 107 is pressed (i.e., preloaded) against the ESC base assembly 105.

[0035] During operation, the ESC base assembly 105 is typically maintained in an RF hot state. Facility plate 107 includes wall portions 230 and is coupled to the ESC 103 by a seal 232. In one embodiment, which may be combined with other embodiments described herein, the lower insulator 212 of facility plate 107 maintains a vacuum region 222 via the seal 232. The wall portions 230 coupled to the ESC 103 by the seal 232 protect the material of the ESC base assembly 105 from potential corrosion and / or erosion resulting from contact with process gases.

[0036] Vacuum zone 222 is defined by ESC 103, ESC base assembly 105, facility plate 107, and seal 232. Vacuum zone 222 prevents condensation on the cooled back side of ESC 103 by having a structure independent of processing zone 110. Figure 1 The pressure (shown in the figure) is used to prevent process gases from entering the substrate support assembly 101 and to provide thermal insulation between the ESC substrate assembly 105 and the facility plate 107. In one embodiment, which may be combined with other embodiments described herein, the facility plate 107 comprises an aluminum-containing material.

[0037] Facility channel 113 of facility panel 107 is machined within the facility panel and sealed using cover 238. In one example, cover 238 is soldered to facility panel 107 to seal facility channel 113. Inlet 240 of facility channel 113 is in fluid communication with inlet conduit 244, which is disposed through dielectric plate 109 and ground plane 111. Outlet 242 of facility channel 113 is in fluid communication with outlet conduit 246, which is disposed through dielectric plate 109 and ground plane 111. Inlet conduit 244 and outlet conduit 246 have connection inlet 250 connected to facility inlet conduit 127 and connection outlet 252 connected to facility outlet conduit 129. During operation, facility panel 107 is typically maintained in an RF hot state.

[0038] The base channel 115 of the ESC base assembly 105 includes an inlet 254 in fluid communication with an inlet conduit 258 disposed through the facility plate 107, dielectric plate 109, and ground plane 111. The outlet 256 of the base channel 115 is in fluid communication with an outlet conduit 260 disposed through the facility plate 107, dielectric plate 109, and ground plane 111. The inlet conduit 258 and outlet conduit 260 are disposed within a vacuum region 222 of the substrate support assembly 101. The inlet conduit 258 and outlet conduit 260 are connected to corresponding interface blocks 270. In one embodiment, which can be combined with other embodiments described herein, the interface block 270 is made of stainless steel. The inlet conduit 258 includes a fluid inlet conduit 266 and a vacuum channel 262. The jacketed outlet conduit 260 includes a fluid outlet conduit 268 and a vacuum channel 264. Figure 3 The interface block 270 is described in more detail.

[0039] Inlet conduit 258 and outlet conduit 260 include a base inlet 272, a vacuum channel 276, a base outlet 274, and a vacuum channel 278. Base inlet 272 connects fluid inlet conduit 266 to base inlet conduit 123. Base outlet 274 connects fluid outlet conduit 268 to base outlet conduit 125. Vacuum channel 276 is connected to vacuum conduit 280, which is in fluid communication with vacuum source 284, and vacuum channel 278 is connected to vacuum conduit 282, which is also in fluid communication with vacuum source 284. Both vacuum channels 276 and 278 are in fluid communication with vacuum region 222. Coupling vacuum source 284 to vacuum region 222 allows the pressure to be maintained in vacuum region 222 to be independent of the pressure in processing region 110. In one embodiment, which may be combined with other embodiments described herein, fluid inlet conduit 266 and fluid outlet conduit 268 are coupled to ESC base assembly 105 via seal 232 to maintain pressure in vacuum region 222.

[0040] The substrate support assembly 101 also includes one or more lift pin assemblies 286 for receiving lift pins (not shown) for raising the substrate 124 above the support surface 130 of the ESC 103 to facilitate robotic transport into and out of the plasma processing chamber 100. Each of the one or more lift pin assemblies 286 includes a lift pin guide 288 disposed through the ESC 103, the ESC base assembly 105, the facility plate 107, the dielectric plate 109, and the ground plane 111. A portion 290 of the lift pin guide 288 disposed through the ESC base assembly 105 is surrounded by a threaded bushing 292 that holds the lift pin guide 288 in place. The lift pin guide 288 is coupled to the ESC 103 via a seal 232 to maintain chamber vacuum and insulation. In one embodiment that can be combined with other embodiments described herein, ESC 103 includes one or more gas passages (not shown) for providing a back-side heat transfer gas (such as helium) to the back side of the substrate 124 and the support surface 130 of ESC 103.

[0041] Figure 3 yes Figure 2 A cross-sectional view of a portion of the substrate support assembly 101. Interface block 270 includes connector 300, which facilitates coupling of fluid outlet conduit 268 to the substrate support assembly 101. Specifically, connector 300 couples the tubular member 305 of fluid outlet conduit 268 to ground plane 111. Although not shown or described in detail, fluid inlet conduit 266 includes... Figure 3 The dedicated interface connection (i.e., interface block 270), connector (i.e., connector 300), and tubular member (i.e., tubular member 305) described herein.

[0042] Connector 300 includes a body 302, which is coupled to ground plane 111 by at least one fastener 310 (such as a screw or bolt). Figure 3 The cross-sectional view shows only one fastener, but the connector 300 is coupled to the ground plane 111 using up to approximately three fasteners. A portion of the ground plane 111 includes a pocket 315 formed therein. Figure 3 In the cross-sectional view, only one pocket is shown, but the number of pockets is equal to the number of fasteners used with connector 300. A biasing assembly 320 coupled to fastener 310 is located in the pocket 315. The biasing assembly 320 includes a plurality of spring forming elements 325 biased against each other, as well as fastener 310 and pocket 315. Each of the spring forming elements 325 compresses and expands based on the temperature of the substrate support assembly 101. For example, when refrigerant is supplied to the substrate support assembly 101 (e.g., when the substrate support assembly 101 is cooled), the spring forming element 325 expands. When the substrate support assembly 101 is not cooled, the spring forming element 325 compresses. Therefore, the biasing assembly 320 (one or a combination of connector 300, spring forming elements 325, and pocket 315) allows connector 300 to move at least perpendicularly (in the Z direction) relative to ground plane 111 during use. Each of the spring forming elements 325 may be a disc spring washer, such as a Bainck washer.

[0043] Connector 300 also includes an annular pouch 330 defining a portion of a dynamic or sliding seal 335. The sliding seal 335 also includes a resilient seal 340, such as an O-ring. The sliding seal 335 allows the connector 300 to move vertically relative to the ground plane 111 during use and maintains a vacuum or negative pressure from ambient or atmospheric pressure. For example, during use of the substrate support assembly 101, a gap 345 formed along the length of the tubular member 305 between the outer surface of the tubular member 305 and portions of the connector 300, dielectric plate 109, and ground plane 111 is maintained under vacuum pressure. Conversely, the outer surface 350 of the connector 300 is in fluid communication with ambient or atmospheric conditions. Therefore, the sliding seal 335 includes an hermetically tight seal to maintain pressure within and without the connector 300. Additionally, during use, the temperature of the substrate support assembly 101 near the sliding seal 335 is at or near room temperature, which prevents deterioration of the resilient seal 340.

[0044] Connector 300 is also coupled to the lower surface 355 of ground plane 111 by thermal pad 360. Thermal pad 360 is a thermally conductive gel material in pad form. Thermal pad 360 includes silicone material. Connector 300 also includes one or more first or lower channels 365 and one or more second or upper channels 370. Although in Figure 3The cross-sectional view shows only one of the lower channels 365 and one of the upper channels 370; the connector 300 may have three, four, or more of each of the lower channels 365 and each of the upper channels 370. As will be explained in more detail below, the lower channels 365 and the upper channels 370 allow for vacuum pumping around the tubular member 305. For example, negative pressure can be provided through the gap 345 by pumping through the lower channels 365 and the upper channels 370.

[0045] The tubular member 305 includes a channel 375 formed along its length for allowing refrigerant to flow to the cryogenic cooler 117. The tubular member 305 also includes an end guide 380 and a spring seal 385. (See below) Figure 5 As shown, the tubular member 305 includes end guides 380 and spring seals 385 at both ends. As will be shown in more detail in FIG. 6, the end guides 380 hold the spring seals 385 in place and / or limit compression of the spring seals 385. The ends of the end guides 380 also prevent the tubular member 305 from tilting due to the radial expansion and contraction of the substrate support assembly 101. For example, the end guides 380 allow the tubular member 305 to move laterally in the X / Y plane (during use of the substrate support assembly 101, e.g., radial expansion and contraction). The end guides 380 also allow vacuum pumping while minimizing arcing at the interface of the tubular member 305 with the connector 300 and ESC 103.

[0046] Figure 4 This is an isometric view of the connector 300 disclosed herein. The connector 300 includes a central opening 400, the dimensions of which are configured to receive (e.g., ...). Figure 3 (As shown in the diagram) a tubular member 305. Additionally, the connector 300 also includes a flange 405. The flange 405 includes a plurality of through holes 410, each through hole 410 being adapted to receive (e.g., Figure 3 (As shown) Fastener 310. Connector 300 also includes a first or upper shoulder 415 and a second or lower shoulder 420. (as shown) Figure 3 The annular bag portion 330 shown is defined between the upper shoulder portion 415 and the lower shoulder portion 420.

[0047] Figure 5 This is a schematic cross-sectional view illustrating one embodiment of a vacuum path 500 passing through the substrate support assembly 101. The vacuum path 500 in... Figure 5The vacuum path 500 is indicated by an arrow. It is a conductive path from the first end 505 of the tubular member 305 to the second end 510 of the tubular member 305. The conductive path includes flow through a void space 515 in or around the end guide 380 to a gap 345. In some embodiments, a portion of the outer surface of the tubular member 305 includes a sleeve 520. The sleeve 520 includes a gap 525 formed between the outer surface of the sleeve 520 and the ESC base assembly 105, the dielectric plate 109, and the ground plane 111. In some embodiments, the gap 345 is a first or inner channel 530, and the gap 525 is a second or outer channel 535. Seals 540 (such as O-rings) and sliding seals 335 seal the conductive paths extending through the various layers of the tubular member 305.

[0048] In some embodiments, the inner channel 530 includes a spiral or helical channel 545, which includes a portion formed in the outer surface of the tubular member 305 and the inner surface of the sleeve 520.

[0049] The conductive path also flows through a port 555 formed in the sleeve 520, which is in fluid communication with the inner channel 530 and / or the outer channel 535. The conductive path also extends into the connector 300 via a plurality of longitudinal channels 560, which are in fluid communication with the lower channel 365 of the connector 300.

[0050] like Figure 5 As shown, both the first end 505 and the second end 510 include a spring seal 385. The spring seal 385 comprises a coil spring made of a metallic material, such as stainless steel wrapped in soft plastic. Figure 7 An example of spring seal 385 is shown in the image. Similarly, as... Figure 5 As shown, both the first end 505 and the second end 510 of the tubular member 305 include an end guide 380.

[0051] Figure 6A and Figure 6B These are cross-sectional views of the upper guide 600A and the lower guide 600B, respectively. The upper guide 600A and the lower guide 600B can be used as... Figure 3 and Figure 5 The end guide 380 having a tubular member 305 as described herein.

[0052] The upper guide 600A and the lower guide 600B include a tubular body 602 made of a metallic material (such as stainless steel). The tubular body 602 includes a first end 605 and a second end 610 opposite to the first end 605. The tubular body 602 includes an inner diameter 615, the size of which is configured to receive either the first end 505 or the second end 510 of the tubular member 305 (e.g., stainless steel).Figure 5 (As shown in the diagram). The tubular body 600 includes an inner wall 620 and an outer wall 625. A cone 630 is shown at the interface between the second end 610 and the inner wall 625.

[0053] The tubular body 602 of the upper guide 600A includes a flange 635 at its first end 605. The flange 635 extends radially outward from the outer wall 625. The flange 635 includes a first surface 645, a side surface 650, and a second surface 655. The first surface 645 is generally orthogonal to the plane of the inner wall 620 or the outer wall 625. The side surface 650 is generally parallel to the plane of the inner wall 620 or the outer wall 625. The second surface 655 is generally parallel to the first surface 645. An interface 660 transitions the second surface 655 to the outer wall 625.

[0054] The first surface 645 of the upper guide 600A includes a contact surface 640 adapted to contact the ESC base assembly 105 (at one end of the tubular member 305) and the connector 300 (at the other end of the tubular member 305). Similar to the upper guide 600A, the lower guide 600B includes a first surface 645. The contact surface 640 includes a coating 665. The coating 665 is a polymeric material, such as a fluoropolymer, including but not limited to materials based on perfluoroalkoxyalkanes (PFAs).

[0055] Figure 7 This is a schematic partial isometric view of one embodiment of the spring seal 385. The spring seal 385 includes a sealing assembly 700. The sealing assembly 700 includes a polymer body 705 having a spring 710 disposed in a channel 715 within the polymer body 705. Although Figure 7 The sealing assembly 700 is shown as a face seal, but embodiments described herein may include a piston (i.e., radial) seal or a metal seal having polytetrafluoroethylene (PTFE) as the polymer body 705. The seal described herein provides for sealing the vacuum region 222 at temperatures between about -260 degrees Celsius and about 290 degrees Celsius. In one embodiment, which may be combined with other embodiments described herein, the spring 710 comprises a material containing stainless steel, a nickel alloy, a nickel-chromium alloy, and a cobalt-chromium-nickel-molybdenum alloy. The sealing assembly 700 allows sealing of ESC 103 at low temperatures. The sealing assembly 700 is operable at temperatures between about -260 degrees Celsius and about 290 degrees Celsius.

[0056] As described in this article, the end guide 380 is as follows Figure 5The vacuum path 500 described herein provides flow. The end guide 380 prevents excessive compression of the spring seal 385 (in the longitudinal (length) direction of the tubular member 305) but allows limited lateral movement of the tubular member 305. However, radial expansion and contraction of the substrate support assembly 101 due to temperature changes during use will cause the tubular member 305 to tilt or become stuck. Tilting or sticking may cause refrigerant fluid leakage. However, coating 665 is used to reduce friction between the mating surfaces of the ESC substrate assembly 105 and the tubular member 305, on which the end guide 380 is located. Therefore, during use, when the substrate support assembly 101 expands or contracts, coating 665 allows the tubular member 305 to slide relative to the mating surfaces. Additionally, coating 665 is dielectric, which minimizes or eliminates arcing in or along the vacuum path 500.

[0057] Although the foregoing is directed to examples of this disclosure, other and further examples of this disclosure may be devised without departing from the basic scope of this disclosure, and the scope of this disclosure is determined by the following claims.

Claims

1. A substrate support assembly, comprising: The main body, the main body includes: An electrostatic chuck substrate assembly having a channel configured for fluid coupling to a cryogenic cooler; Facility plate, the facility plate being disposed below the electrostatic chuck base assembly; and A grounding plate, the grounding plate being coupled to the bottom surface of the facility plate; A tubular member having a fluid conduit disposed through the tubular member, the tubular member being disposed through the facility plate and the ground plane and fluidly coupled to the electrostatic chuck base assembly, the tubular member having a first end guide disposed at a first end extending beyond the bottom surface of the ground plane and a spring seal, the first end guide being disposed around the tubular member and extending beyond the first end of the tubular member; and A connector coupled to the bottom surface of a ground plane, the connector accommodating a portion of the tubular member, a first end guide and a spring seal disposed below the bottom surface of the ground plane and within the connector, the first end guide contacting the tubular member and the connector in a manner that restricts axial compression of the spring seal, the spring seal providing an axial seal between the spring seal and the connector, the connector including a biasing assembly and a fastener disposed in a pocket formed in the ground plane.

2. The substrate support assembly of claim 1, wherein the biasing assembly includes a plurality of spring forming members coupled between the fastener and the pocket portion.

3. The substrate support assembly of claim 1, wherein the connector includes a sliding seal surrounding the body of the connector.

4. The substrate support assembly of claim 1, wherein the connector includes one or more vacuum channels formed in the connector.

5. The substrate support assembly of claim 1, further comprising an electrostatic chuck disposed on the electrostatic chuck substrate assembly, wherein the electrostatic chuck has an RF electrode.

6. The substrate support assembly of claim 5, further comprising a bonding layer at the interface between the bottom surface of the electrostatic chuck and the top surface of the electrostatic chuck substrate assembly.

7. The substrate support assembly of claim 1, wherein the connector is coupled to the lower surface of the ground plane by a thermal pad.

8. The substrate support assembly of claim 1, further comprising a second end guide disposed at a second end of the fluid conduit, the second end guide contacting the electrostatic chuck substrate assembly and comprising a friction-reducing coating disposed on the second end guide.

9. The substrate support assembly of claim 8, wherein the first end guide includes a friction-reducing coating disposed on the first end guide.

10. A substrate support assembly, comprising: A base assembly for supporting an electrostatic chuck; Facility panel, the facility panel being coupled to the base assembly; Dielectric plate, the dielectric plate being coupled to the facility plate; A grounding plate, the grounding plate being coupled to the facility plate; A tubular member having a fluid conduit disposed through the tubular member, the tubular member being disposed through the facility plate and the ground plane and fluidly coupled to the electrostatic chuck base assembly, the tubular member having a first end guide disposed at a first end extending beyond the bottom surface of the ground plane and a spring seal, the first end guide being disposed around the tubular member and extending beyond the first end of the tubular member; as well as A connector coupled to the bottom surface of a ground plane, the connector accommodating a portion of the tubular member, a first end guide and a spring seal disposed below the bottom surface of the ground plane and within the connector, the first end guide contacting the tubular member and the connector in a manner that restricts axial compression of the spring seal, the spring seal providing an axial seal between the spring seal and the connector, the connector including a biasing assembly and fasteners, and a sliding seal disposed in a pocket formed in the ground plane, the sliding seal surrounding the body of the connector.

11. The substrate support assembly of claim 10, further comprising a bonding layer disposed on the top surface of the substrate assembly.

12. The substrate support assembly of claim 10, wherein the connector is coupled to the lower surface of the ground plane by a thermal pad.

13. The substrate support assembly of claim 10, further comprising a second end guide disposed at a second end of the fluid conduit, the second end guide contacting the electrostatic chuck substrate assembly and comprising a friction-reducing coating disposed on the second end guide.

14. The substrate support assembly of claim 13, wherein the first end guide includes a friction-reducing coating disposed on the first end guide.

15. The substrate support assembly of claim 10, further comprising a sleeve provided around the fluid conduit.

16. The substrate support assembly of claim 15, wherein the sleeve includes a gap formed between the outer surface of the sleeve and the substrate assembly, the dielectric plate and the ground plane.

17. A substrate support assembly, comprising: electrostatic chuck; A base assembly coupled to the electrostatic chuck, the base assembly having a base channel configured to allow flow of a cryogenic fluid for cooling the electrostatic chuck; A facility plate coupled to the base assembly, the facility plate having facility channels configured to allow temperature-controlled fluid to flow through the facility channels; Dielectric plate, the dielectric plate being coupled to the facility plate; A grounding plate, the grounding plate being coupled to the facility plate; A tubular member having a fluid conduit disposed through the tubular member, the tubular member being disposed through the facility plate and the grounding plate, the tubular member having a first end guide and a spring seal disposed at a first end extending beyond the bottom surface of the grounding plate; as well as A connector coupled to the bottom surface of a ground plane, the connector receiving a portion of the tubular member, a first end guide and a spring seal disposed below the bottom surface of the ground plane and within the connector, the first end guide contacting the tubular member and the connector in a manner that restricts axial compression of the spring seal, the spring seal providing an axial seal between the spring seal and the connector, the connector including a biasing assembly and fasteners, and a sliding seal disposed in a pocket formed in the ground plane, the sliding seal surrounding the body of the connector.

18. The substrate support assembly of claim 17, further comprising a bonding layer disposed on the top surface of the substrate assembly.

19. The substrate support assembly of claim 17, wherein the connector is coupled to the lower surface of the ground plane by a thermal pad.

20. The substrate support assembly of claim 17, further comprising a second end guide disposed at a second end of the fluid conduit, the fluid conduit being fluidly coupled to the base channel, wherein the second end guide includes a friction-reducing coating disposed on the second end guide.

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