Fluid conduits and flanges for high bias applications

Abstract

Described herein are methods and apparatus for cooling a semiconductor chamber component including a power supply region, a ground region, and a fluid conduit disposed within the semiconductor chamber component and passing through the power supply region and the ground region, the fluid conduit comprising a ceramic material.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 412,266, filed September 30, 2022, which is incorporated herein by reference in its entirety. [Background technology]

[0002] FIELD OF THE DISCLOSURE

[0002] Embodiments of the present disclosure relate generally to semiconductor chamber components, and more particularly to cooled substrate support assemblies for use in radio frequency fields.

[0003] 2. Description of Related Art

[0003] Reliable fabrication of sub-nanometer features is one of the key challenges in the next generation of very large scale integration (VLSI) and ultra-large scale integration (ULSI) semiconductor devices. However, as circuit technology limits are pushed, ever-shrinking dimensions place increasing demands on VLSI and ULSI interconnect technology for processing power. Reliable formation of gate structures on substrates is critical to the success of VLSI and ULSI, as well as to the continuing effort to increase circuit density and quality on individual substrates and dies.

[0004] To reduce manufacturing costs, integrated chip (IC) manufacturing demands higher throughput and better device yield and performance for every silicon substrate processed. Several manufacturing techniques being explored for next-generation devices currently under development require processing at cryogenic temperatures. Dry reactive ion etching of a substrate maintained uniformly at cryogenic temperatures allows ions to bombard the upward-facing surface of a material deposited on the substrate with minimal spontaneous etching, resulting in trenches with smooth, vertical sidewalls. Furthermore, the selectivity of etching one material over another can be improved at cryogenic temperatures. For example, the selectivity between silicon (Si) and silicon dioxide (SiO2) increases exponentially as temperature decreases.

[0005]

[0005] The operation of a substrate support assembly to enable cryogenic processing often relies on the use of a coolant circulated through the substrate support assembly. Because the conduits used to route the coolant span the grounded and powered portions of the substrate support assembly, the coolant must be sufficiently electrically insulated to prevent electrical shorting of the substrate support assembly components to ground. However, in high bias power applications, the high direct current (DC) voltages and ohmic heating generated in high bias radio frequency (RF) power applications can cause cracks in the conduits. In other words, in high bias power applications, the conduits can experience significant parasitic current losses, potentially causing cracks in the conduits.

[0006]

[0006] Therefore, there is a need for an improved substrate support assembly including a conduit design that can withstand high bias power processing recipes while a cryogenically flowing coolant flows therethrough.

[0006] Described herein, in accordance with one embodiment, is a method and apparatus for cooling a semiconductor chamber. The semiconductor chamber component includes a power supply region, a ground region, and a fluid conduit disposed within the semiconductor chamber component and passing through the power supply region and the ground region, the fluid conduit comprising a ceramic material. Summary of the Invention

[0007]

[0007] Described herein, according to one embodiment, is a method and apparatus for cooling a semiconductor chamber component including a power supply region, a ground region, and a fluid conduit disposed within the semiconductor chamber component and passing through the power supply region and the ground region, the fluid conduit comprising a ceramic material.

[0008]

[0008] In another embodiment, the substrate support assembly includes a facility plate, an insulator plate disposed between the ground plate and the facility plate, a fluid conduit disposed within the substrate support assembly through the facility plate and the insulator plate, and a connector coupled to the ground plate that accommodates a portion of the fluid conduit, the connector having a central opening with an inner diameter of between about 0.7 inches and about 0.8 inches.

[0009] In another embodiment, a substrate support assembly includes a facilities plate, a ground plate coupled to the facilities plate, a fluid conduit disposed within the substrate support assembly through the facilities plate and the ground plate, the fluid conduit having an outer surface surrounded by a polytetrafluoroethylene sleeve, and a connector coupled to the ground plate that houses a portion of the fluid conduit. The connector couples a tubular member of the fluid conduit to the ground plate. The connector and the fluid conduit comprise the same ceramic material.

[0010]

[0010] In order that the features of the present disclosure as described above may be understood in detail, a more detailed description of the present disclosure, briefly summarized above, will be had by reference to embodiments. Some embodiments are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings illustrate only exemplary embodiments of the present disclosure and therefore should not be considered as limiting its scope, as the present disclosure may admit of other equally effective embodiments. [Brief explanation of the drawings]

[0011] [Figure 1]1 is a schematic cross-sectional view of an exemplary plasma processing chamber. [Figure 2A]

[0012] 1 is a schematic cross-sectional view of an exemplary plasma processing chamber. [Figures 2B-2D] 1 is a schematic cross-sectional view of an exemplary plasma processing chamber. [Figure 3]

[0013] 3 is a cross-sectional view of a portion of the substrate support assembly of FIG. 2. [Figure 4A]

[0014] 1 is a schematic diagram of a connector disclosed herein. [Figure 4B] 1 is a schematic diagram of a connector disclosed herein. [Figure 5]

[0015] 1 is a schematic cross-sectional view illustrating one embodiment of a connector through a substrate support assembly as described herein. DETAILED DESCRIPTION OF THE INVENTION

[0012]

[0016] For ease of understanding, where possible, the same reference numerals have been used to designate identical elements that are common to multiple figures. It is envisioned that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

[0013]

[0017] Embodiments described herein provide a substrate support assembly that enables cryogenic operation of an electrostatic chuck (ESC) whereby a substrate disposed thereon is maintained at a cryogenic processing temperature suitable for processing, while other surfaces of the processing chamber are maintained at another temperature. Cryogenic processing temperature (i.e., the temperature of the substrate) is intended to refer to a temperature below −10° C. at the substrate support.

[0014]

[0018] Also described herein are substrate support assemblies that include one or more conduits for conveying fluid within the substrate support assembly between a powered portion and a grounded portion of the substrate support assembly that are less susceptible to arcing and cracking at high bias power levels. The conduits described herein are less susceptible to arcing and cracking at high bias power levels compared to conduits used in conventional substrate support assemblies, thereby significantly improving the reliability, service intervals, and useful life of the substrate support assembly. While the conduits are primarily described as implemented in substrate support assemblies configured to enable cryogenic operation, the conduits may be utilized in other substrate support assemblies or other semiconductor processing chamber components, where a fluid is conveyed in a conduit that traverses the grounded and powered portions of the processing chamber component.

[0015]

[0019] Also described herein is a substrate support assembly including one or more fluid conduits for conveying a fluid at cryogenic temperatures, the fluid conduits configured to reduce arcing, reduce RF current loss to the fluid conduits due to insufficient tube impedance, reduce ohmic heating due to parasitic currents, and reduce breakage of the fluid conduits caused by thermal expansion of components of the substrate support assembly.

[0016]

[0020] The substrate support assemblies described may be utilized in multiple types of plasma processing chambers, such as etch chambers, physical vapor deposition chambers, chemical vapor deposition chambers, ion implantation chambers, plasma processing chambers, annealing chambers, among others, and other systems where it is desirable to process substrates maintained at cryogenic processing temperatures. However, it should be noted that the substrate support assemblies and chamber components described herein may be utilized at other processing temperatures.

[0017]

[0021] FIG. 1 is a schematic cross-sectional view of an exemplary plasma processing chamber 100 having a substrate support assembly 101. The described substrate support assembly 101 can be utilized when the ability to uniformly maintain a surface or workpiece, such as a substrate 124, at a cryogenic processing temperature is desirable. Dry reactive ion etching of a substrate 124 maintained at a cryogenic processing temperature allows ions to bombard the upward-facing surface of a material disposed on the substrate 124 with less spontaneous etching, forming trenches with smooth, vertical sidewalls. For example, while ion diffusion within the pores of a low-k dielectric material disposed on a substrate 124 maintained uniformly at a cryogenic processing temperature is reduced, ions continue to bombard the upward-facing surface of the low-k dielectric material, forming trenches with smooth, vertical sidewalls. Furthermore, the etch selectivity of one material over another can be improved at cryogenic processing temperatures. For example, the selectivity between silicon (Si) and silicon dioxide (SiO) increases exponentially as temperature decreases.

[0018]

[0022] The plasma processing chamber 100 includes a chamber body 102 having sidewalls 104, a bottom 106, and a lid 108 that surround a processing region 110. An injector 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 injector 112 to enable delivery of process gases to the processing region 110. The injector 112 may be one or more nozzles or inlet ports, or alternatively, a showerhead. The process gases, along with any process by-products, are removed from the processing region 110 through exhaust ports 116 formed in the sidewalls 104 or bottom 106 of the chamber body 102. The exhaust ports 116 are coupled to a pumping system 140, which includes a throttle valve and a pump that are utilized to control the vacuum level within the processing region 110.

[0019]

[0023] The process gas may be excited to form a plasma in the process region 110. The process gas may be excited by capacitively or inductively coupling RF power to the process gas. In an embodiment shown in FIG. 1, which can be combined with other embodiments described herein, multiple coils 118 are positioned above the lid 108 of the plasma processing chamber 100 and coupled to an RF power source 122 via a matching network 120.

[0020]

[0024] The substrate support assembly 101 is positioned in a processing region 110 below the implanter 112. The substrate support assembly 101 includes an ESC 103 and an ESC base assembly 105. The ESC base assembly 105 is coupled to the ESC 103 and an equipment plate 107. The equipment plate 107 is supported by a ground plate 111 and is configured to facilitate electrical, cooling, heating, and gas connections to the substrate support assembly 101. The ground plate 111 is supported by the bottom 106 of the processing chamber. An insulator plate 109 insulates the equipment plate 107 from the ground plate 111. The ground plate 111 represents a ground region of the substrate support assembly 101. The ESC 103, the ESC base assembly 105, the equipment plate 107, and the insulator plate 109 represent a power feed region of the substrate support assembly 101.

[0021]

[0025] ESC base assembly 105 includes base channel 115 coupled to cryocooler 117. Cryocooler 117 supplies a base fluid, such as a refrigerant, to base channel 115, thereby maintaining ESC base assembly 105, and consequently substrate 124, at a predetermined cryogenic temperature. Similarly, facilities plate 107 includes facilities channel 113 coupled to chiller 119. Chiller 119 supplies facilities fluid to facilities channel 113 such that facilities plate 107 is maintained at a predetermined temperature. In one embodiment, the base fluid maintains ESC base assembly 105 at a temperature lower than the temperature of facilities plate 107.

[0022]

[0026] 2A , the cryocooler 117 is in fluid communication with the base channel 115 via a base inlet conduit 123 connected to an inlet 254 of the base channel 115 and via a base outlet conduit 125 connected to an outlet 256 of the base channel 115 so that the ESC base assembly 105 is maintained at a predetermined cryogenic temperature. In one embodiment, which can be combined with other embodiments described herein, the cryocooler 117 is coupled to a bounding box to control the flow rate of a base fluid. The base fluid comprises a composition that remains liquid at cryogenic temperatures below −50° C. at operating pressure. The base fluid is generally insulating, so that no electrical path is formed through the base fluid as it circulates through the substrate support assembly 101. Non-limiting examples of suitable facility fluids include fluorinated heat transfer fluids. The cryocooler 117 provides the base fluid, which is circulated through the base channel 115 of the ESC base assembly 105. The base fluid flowing through the base channel 115 enables the ESC base assembly 105 to be maintained at a cryogenic temperature, which helps to control the lateral temperature profile of the ESC 103 so that a substrate 124 disposed on the ESC 103 is uniformly maintained at a cryogenic processing temperature. In one embodiment, which can be combined with other embodiments described herein, the cryocooler 117 is operable to maintain a cryogenic temperature of less than about −50° C.

[0023]

[0027] The cooler 119 is in fluid communication with the facility channels 113 via a facility inlet conduit 127 connected to an inlet 240 of the facility channel 113 and a facility outlet conduit 129 connected to an outlet 242 of the facility channel 113 so that the facility plate 107 is maintained at a predetermined ambient temperature. In one embodiment, which can be combined with other embodiments described herein, the cooler 119 is coupled to a bounding box to control the flow rate of the facility fluid. The facility fluid may include a material capable of maintaining an ambient temperature between about −10° C. and about 60° C. The cooler 119 supplies the facility fluid that is circulated through the facility channels 113 of the facility plate 107. The facility fluid is generally insulating so that no electrical paths are formed through the facility fluid as it circulates 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 channels 113 allows the facility plate 107 to be maintained at a predetermined ambient temperature, which helps to maintain the insulator plate 109 at a predetermined ambient temperature.

[0024]

[0028] 1 , ESC 103 has a support surface 130 and a bottom surface 132 opposite support surface 130. In one embodiment, which can be combined with other embodiments described herein, ESC 103 is fabricated from a ceramic material such as alumina (Al2O3), aluminum nitride (AlN), or other suitable material. Alternatively, ESC 103 can be fabricated from a polymer such as polyimide, polyetheretherketone, polyaryletherketone, or the like.

[0025]

[0029] A chuck electrode 126 is disposed within the ESC 103. The chuck electrode 126 may be configured as a unipolar or bipolar electrode, or in any other suitable arrangement. The chuck electrode 126 is coupled to a chuck power supply 134 via an RF filter and fixture plate 107, which provides DC power for electrostatically clamping the substrate 124 to the support surface 130 of the ESC 103. The RF filter prevents the RF power utilized to form a plasma (not shown) within the plasma processing chamber 100 from damaging or causing electrical interference to electrical equipment outside the chamber.

[0026]

[0030] The ESC 103 includes one or more resistive heaters 128 embedded therein. The resistive heaters 128 are utilized to control the temperature of the ESC 103, which is cooled by the ESC base assembly 105, thereby maintaining a cryogenic processing temperature suitable for processing a substrate 124 disposed on the support surface 130 of the substrate support assembly 101. The resistive heaters 128 are coupled to a heater power supply 136 via a fixture plate 107 and an RF filter. The RF filter prevents RF power utilized to form a plasma (not shown) within the plasma processing chamber 100 from damaging or causing electrical interference to electrical equipment outside the chamber. The heater power supply 136 is capable of supplying 500 watts or more of power to the resistive heaters 128. The heater power supply 136 includes a controller 138 utilized to control the operation of the heater power supply 136, which is generally configured to maintain a predetermined cryogenic temperature for the substrate 124. In one embodiment, which can be combined with other embodiments described herein, the resistive heater 128 includes multiple laterally separated heating zones, and the controller enables preferential heating of at least one zone of the resistive heater 128 relative to resistive heaters 128 located in one or more of the other zones. For example, the resistive heaters 128 may be concentrically arranged within the multiple separated heating zones. The resistive heater 128 maintains the substrate 124 at a cryogenic processing temperature suitable for processing. In one embodiment, which can be combined with other embodiments described herein, the cryogenic processing temperature is less than about −10° C. For example, the cryogenic processing temperature is between about −10° C. and about −150° C.

[0027]

[0031] The substrate support assembly 101 may include one or more temperature probe assemblies disposed therein that are utilized to provide feedback to balance the heating and cooling provided by the ESC base assembly 105 and the resistive heaters 128 of the ESC 103 to maintain a desired substrate processing temperature.

[0028] Ceramic Refrigerant Feed Tube

[0032] Returning to FIG. 2A , the exemplary substrate support assembly 101 is configured to enable cryogenic operation of the ESC 103 such that a substrate 124 disposed thereon is maintained at a cryogenic processing temperature. The ESC 103 is coupled to the ESC base assembly 105. In one embodiment, which may be combined with other embodiments described herein, the ESC 103 is secured to the ESC base assembly 105 with a bonding layer 202. The bonding layer 202 may include an organic or inorganic material. In some embodiments, which may be combined with other embodiments described herein, the bonding layer 202 may include an epoxy or metallic material. The chuck electrode 126 is coupled to the chuck power supply 134 via a first insulated wire 204 disposed through a first bore 212 in a lower insulator of the equipment plate 107 and an upper insulator 214 of the ESC base assembly 105.

[0029]

[0033] Facilities plate 107 includes plate portion 229 and wall portion 230. Plate portion 229 of ESC base assembly 105 is coupled to facilities plate 107 using one or more first screw assemblies such that a vacuum region 222 exists between ESC base assembly 105 and facilities plate 107.

[0030]

[0034] The facilities plate 107 includes a wall 230 coupled to the ESC 103 by a seal 232. In one embodiment that can be combined with embodiments described herein, a lower insulator of the facilities plate 107 maintains a vacuum region 222 via the seal 232. The wall 230 coupled to the ESC by the seal 232 protects the materials of the ESC base assembly 105 from potential corrosion and / or erosion due to contact with process gases. The vacuum region 222 is defined by the ESC 103, the ESC base assembly 105, the facilities plate 107, and the seal 232. The vacuum region 222 prevents condensation on the backside of the cooling plate, prevents process gases from entering the substrate support assembly 101 by having a pressure that is independent of the pressure in the processing region 110, and provides thermal insulation between the ESC base assembly 105 and the facilities plate 107. In one embodiment that can be combined with other embodiments described herein, the facilities plate 107 includes an aluminum-containing material.

[0031]

[0035] The equipment channel 113 in the equipment plate 107 is machined into the equipment plate and sealed with a cover 238. In one embodiment, the cover 238 is welded to the equipment plate 107, sealing the equipment channel 113. An inlet 240 of the equipment channel 113 is in fluid communication with an inlet conduit 244 disposed through the insulator plate 109 and the ground plate 111. An outlet 242 of the equipment channel 113 is in fluid communication with an outlet conduit 246 disposed through the insulator plate 109 and the ground plate 111. The inlet conduit 244 and the outlet conduit 246 are connected to a junction 248 having a connection inlet 250 connected to the equipment inlet conduit 127 and a connection outlet 252 connected to the equipment outlet conduit 129. During operation, the equipment plate 107 is generally maintained at an RF hot state.

[0032]

[0036] As described above, the inlet conduit 244 and the outlet conduit 246 span the powered and grounded portions of the substrate support assembly 101. That is, the inlet conduit 244 and the outlet conduit 246 extend through the substrate support assembly 101 between the power feed equipment plate 107 and the ESC base assembly 105 (i.e., the powered portion) and between the ground insulator plate 109 and the substrate support assembly 101 (i.e., the grounded portion).

[0033]

[0037] As shown in the enlarged portion of FIG. 2B , conduit 244 includes first end 291 and second end 293. Conduit 244 also has an exterior surface 295 connecting first end 291 and second end 293. As shown in FIG. 2C , exterior surface 295 of each end 291, 293 includes a sealing surface 289. Sealing surface 289 is polished to facilitate sealing with equipment plate 107 and connection 248. In one embodiment, exterior surface 295 of each end 291, 293 is polished to at least 32 μin Ra or smoother. Seal 297 may be disposed between polished sealing surface 289 of exterior surface 295, equipment plate 107, and connection 248 to prevent leakage. In one embodiment, seal 297 may be configured as described with reference to seal 232 or in another suitable manner.

[0034]

[0038] 2D illustrates an alternative sealing method. As shown in FIG. 2A', a fitting 299 can be sealably coupled to the outer surface 295 of each end 291, 293. The fittings 299 are configured to sealingly mate with complementary mating surfaces (e.g., male / female threads, compression fittings, brazed rings, etc.) of the equipment plate 107 and / or connection 248. In one embodiment, the fittings 299 can be metal cylinders brazed to the conduit 244 and equipment plate 107 at one end 291, and a second fitting 299 can be brazed to the conduit 244 and connection 248 at the other end 293. While the seals 297 are shown and described as piston seals, the seals 297 can alternatively be configured as face seals.

[0035]

[0039] 2A , the base channel 115 of the ESC base assembly 105 includes an inlet 254 of the base channel 115 in fluid communication with a jacketed inlet conduit 258 disposed through the facility plate 107, the insulator plate 109, and the ground plate 111. The outlet 256 of the base channel 115 is in fluid communication with a jacketed outlet conduit 260 disposed through the facility plate 107, the insulator plate 109, and the ground plate 111. The jacketed inlet conduit 258 and the jacketed outlet conduit 260 are connected to a boundary block 270. In one embodiment, which can be combined with other embodiments described herein, the boundary block 270 is fabricated from stainless steel. The jacketed 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. Boundary block 270 includes 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 in fluid communication with vacuum source 284. Coupling vacuum source 284 to vacuum region 222 allows a pressure to be maintained in vacuum region 222 that is independent of the pressure in processing region 110. In one embodiment, which can be combined with other embodiments described herein, fluid inlet conduit 266 and fluid outlet conduit 268 are coupled to ESC base assembly 105 by seals 232 to maintain pressure in vacuum region 222.

[0036]

[0040] The conduits 244, 246, 266, 268 may also be manufactured as described above, for example, with ends as described with reference to Figure 2A'. The fluid conduits 244, 246, 266, 268 may also be configured with a sleeve 520 (Figure 5), described in more detail below. The sleeve 520 is inserted into an electrically insulating backing tube to provide mechanical strength to the conduits and insulation against RF power.

[0037]

[0041] 2A, to prevent cracking during application of high bias power, the conduits 244, 246, 266, 268 are made from a ceramic material. For example, the ceramic material may include zirconium dioxide, yttrium oxide, magnesium oxide, or any combination thereof. In yet another example, the ceramic material may be fired or sintered zirconia containing, by weight percent, 90% to 100% zirconium dioxide, 10% to 30% yttrium oxide, and 1% to 5% magnesium oxide, or any combination thereof. In one non-limiting example, the ceramic material may be a fired or sintered zirconia containing, by weight percent, 90% to 100% zirconium dioxide, 10% to 30% yttrium oxide, and 1% to 5% magnesium oxide, or any combination thereof. 4 Ω·cm to approximately 10 11 The ceramic material has a desired volume resistivity in the range of Ω·cm. The ceramic material has a density of about 6 g / cm. The ceramic material has a modulus of elasticity of about 192 Gpa. The ceramic material has a flexural strength of about 1,000 MPa. The ceramic material has a thermal conductivity of between about 4 W / m·K and about 6 W / m·K, e.g., about 5 W / m·K. The ceramic material has a coefficient of thermal expansion of between about 9 ppm / °C and about 10 ppm / °C, e.g., about 9.5 ppm / °C.

[0038]

[0042] In other words, the fluid conduits 244, 246, 266, 268 may comprise ceramic materials selected to withstand higher DC voltages and RF power, such as RF frequencies between about 2 MHz and about 13 MHz. Conduits 244, 246, 266, 268 made from these ceramic materials have matched impedance values ​​when the fluid conduits are subjected to RF energy during processing, resulting in matched impedances that reduce parasitic current losses from the conduits 244, 246 to ground. Reducing parasitic current losses in the conduits 244, 246, 266, 268 allows more current to be delivered to the generated plasma, enabling lower bias power levels to be used for high bias power applications. According to some embodiments, the matching fluid conduits 244, 246, 266, 268 may also be refrigerant conduits, thereby providing additional cooling capacity. Therefore, by preventing additional thermal energy from being added to the aligned fluid conduits 244, 246, 266, 268, the cooling capacity of the substrate support assembly 101 is improved.

[0039]

[0043] Thus, this configuration of the conduits 244, 246, 266, 268 prevents cracking under high bias RF power application and substantially prevents arcing between the grounded portions of the conduits 244, 246, 266, 268 of the substrate support assembly 101, advantageously increasing the reliability, service intervals, and service life of the substrate support assembly 101.

[0040] Low capacitance connector for high bias applications

[0044] Figure 3 is a cross-sectional view of a portion of the substrate support assembly 101 of Figure 2. A boundary block 270 includes connectors 300 that facilitate coupling conduits 244, 246, 266, 268 (only conduit 268 is shown for simplicity) to the substrate support assembly 101. In particular, connectors 300 couple tubular members 305 of conduits 244, 246, 266, 268 to the ground plate 111. For example, fluid inlet conduit 266 (not shown in Figure 3) and fluid outlet conduit 268 include a boundary block 270 with connectors 300 and tubular members 305.

[0041]

[0045] The connector 300 includes a body 302. The connector 300 is coupled to a plate of the substrate support assembly 101. For example, the connector 300 is coupled to the ground plate 111 by at least one fastener 310, such as a screw or bolt. Although only one fastener is shown in the cross-sectional view of FIG. 3, up to approximately three fasteners may be utilized to couple the connector 300 to the ground plate 111. A pocket 315 is formed in a portion of the ground plate 111. Although only one pocket is shown in the cross-sectional view of FIG. 3, the number of pockets is equal to the number of fasteners utilized in the connector 300. A biasing assembly 320 coupled to the fastener 310 is positioned in the pocket 315. The biasing assembly 320 includes multiple spring forms 325 biased against one another, as well as the fasteners 310 and the pocket 315. Each spring form 325 compresses and expands based on the temperature of the substrate support assembly 101. For example, when coolant is supplied to the substrate support assembly 101 (e.g., when the substrate support assembly 101 is cooled), the spring forms 325 compress. When the substrate support assembly 101 is not cooled, the spring forms 325 expand. Thus, the biasing assembly 320 (one or a combination of the connector 300, the spring forms 325, and the pocket 315) allows at least vertical (Z-direction) movement of the connector 300 relative to the ground plate 111 during use. Each spring form 325 may be a disc spring washer, such as a Belleville washer.

[0042]

[0046] The connector 300 also includes a dynamic or sliding seal 335. The sliding seal 335 also includes an elastomeric seal 340, such as an O-ring. The sliding seal 335 allows vertical movement of the connector 300 relative to the ground plate 111 during use and maintains a vacuum or negative pressure from ambient or atmospheric pressure. For example, a gap 345 formed between the outer surface of the tubular member 305 and portions of the connector 300, insulator plate 109, and ground plate 111 along the length of the tubular member 305 is maintained at a vacuum pressure during use of the substrate support assembly 101. In contrast, the outer surface 350 of the connector 300 is in fluid communication with ambient or atmospheric conditions. Thus, the sliding seal 335 comprises an airtight seal that maintains pressure inside and outside the connector 300. Furthermore, during use, the temperature of the substrate support assembly 101 near the sliding seal 335 is at or near room temperature, which prevents degradation of the elastomeric seal 340.

[0043]

[0047] The connector 300 is also coupled to the underside 355 of the ground plate 111 by a thermal gasket 360. The thermal gasket 360 is a thermally conductive gel material in the form of a pad. The thermal gasket 360 comprises a silicone material. The connector 300 also includes one or more first or lower channels 365 and one or more second or upper channels 370. While only one of the lower channels 365 and one of the upper channels 370 are shown in the cross-sectional view of FIG. 3, the connector 300 may have three, four, or more of the lower channels 365 and the upper channels 370. As described in more detail below, the lower channels 365 and the upper channels 370 enable vacuum pumping around the tubular member 305. For example, a negative pressure can be applied through the gap 345, which is facilitated by pumping through the lower channels 365 and the upper channels 370.

[0044]

[0048] The tubular member 305 includes channels 375 formed along its length for flowing refrigerant to the cryocoolers 117, 119. The tubular member 305 also includes end guides 380 and spring seals 385. As described below in FIG. 5, the tubular member 305 includes end guides 380 and spring seals 385 at both ends thereof.

[0045]

[0049] FIG. 4A is a top view of a connector according to some embodiments, and FIG. 4B is a cross-sectional view of connector 300. Connector 300 includes a central opening 400 sized to receive tubular member 305 (FIG. 3). Central opening 400 includes an inner diameter 450, a first diameter 451, and a second diameter 452. Inner diameter 450 is the interior surface of connector 300 and partially defines gap 345. Inner diameter 450 is between about 0.7 inches and about 0.8 inches, e.g., about 0.755 inches. First diameter 451 is between about 0.9 inches and about 1.1 inches, e.g., about 1 inch. Second diameter 452 is the diameter of the exterior surface of connector 300. Second diameter 452 is between about 0.9 inches and about 1.1 inches, e.g., about 0.89 inches. Additionally, connector 300 also includes a flange 405. Flange 405 is the connecting portion of connector 300 and allows the connector to be mounted to a plate within substrate support assembly 101. Flange 405 includes a plurality of through holes 410, each adapted to receive a fastener 310 (FIG. 3). Connector 300 also includes an upper shoulder 415 and a second or lower shoulder 420. An annular pocket 330 is defined between upper shoulder 415 and lower shoulder 420. The annular pocket includes an elastomeric seal 340, which seals connector 300 when mounted within substrate support assembly 101.

[0046]

[0050] In some embodiments, the connector 300 is made of the same material as the fluid conduits 244, 246, 266, 268. For example, the connector 300 and the fluid conduits 244, 246, 266, 268 are ceramic. To prevent cracking during application of high bias power, the connector 300 is made of a ceramic material. For example, the ceramic material may include zirconium dioxide, yttrium oxide, magnesium oxide, or any combination thereof. In yet another example, the ceramic material may be fired or sintered zirconia containing, by weight, 90% to 100% zirconium dioxide, 10% to 30% yttrium oxide, and 1% to 5% magnesium oxide, or any combination thereof. In one non-limiting example, the ceramic material may be approximately 10% or more of a sintered or fired zirconia. 4 Ω·cm to approximately 10 11 The ceramic material has a desired volume resistivity in the range of Ω·cm. The ceramic material has a density of approximately 6 g / cm. The ceramic material has a modulus of elasticity of approximately 192 Gpa. The ceramic material has a flexural strength of approximately 1,000 MPa. The ceramic material has a thermal conductivity of between approximately 4 W / m·K and approximately 6 W / m·K, for example, approximately 5 W / m·K. The ceramic material has a thermal expansion coefficient of between approximately 9 ppm / °C and approximately 10 ppm / °C, for example, approximately 9.5 ppm / °C. The inventors have found that when the connector 300 made from ceramic material has an inner diameter 450 of less than approximately 0.8 inches, each of the fluid conduits 244, 246, 266, 268 has a conduit impedance of less than 1,000 Ω. Furthermore, when the connector and fluid conduits 244, 246, 266, 268 are subjected to an RF bias, the entire assembly including the connector 300 and a single one of the fluid conduits 244, 246, 266, 268 has a lower assembly impedance. For example, when the connector 300 and fluid conduit 268 are subjected to a bias frequency of about 20 Hz, the assembly has a lower impedance of about 1.5x10 8 For example, if the connector 300 and fluid conduit 268 are subjected to a bias frequency of about 2 MHz, the assembly will have an impedance of about 2.12x10 4For example, if the connector 300 and fluid conduit 268 are subjected to a bias frequency of approximately 13.56 MHz, the assembly will have an impedance of approximately 3.18x10 3 Ω assembly impedance.

[0047]

[0051] FIG. 5 is a schematic cross-sectional view illustrating one embodiment of a vacuum path 500 through the substrate support assembly 101. The vacuum path 500 is indicated by an arrow in FIG. 5 . The vacuum path 500 is a conductance path from a first end 505 of the tubular member 305 to a second end 510 of the tubular member 305. The conductance path includes flow through an opening 515 in the end guide 380 to the gap 345. In some embodiments, a portion of the outer surface of the tubular member 305 includes a sleeve 520. The sleeve 520 may be made of polytetrafluoroethylene (Teflon), for example, the sleeve is a polytetrafluoroethylene sleeve 520. The sleeve 520 includes a gap 525 formed between its outer surface and the ESC base assembly 105, the insulator plate 109, and the ground plate 111. The sleeve 520 may surround the outer surface of the tubular member 305. A sleeve 520 may extend between the ESC 103 and the second end 510 of the tubular member 305. The sleeve 520 advantageously insulates the RF high temperature ESC 103 from ground and prevents cracking of the tubular member 305.

[0048]

[0052] Additionally, the sleeve 520 increases the resistance of the tubular member 305 to ground. As a result, parasitic current losses in the tubular member 305 are reduced, which reduces ohmic heating of the tubular member 305. In other words, the sleeve 520 insulates the tubular member from the cryogenic temperature on one side of the chamber and the RF high temperature on the other side of the chamber. The sleeve 520 reduces the thermal energy received by the tubular member 305 due to the temperature difference, preventing cracks in the tubular member.

[0049]

[0053] In some embodiments, gap 345 is inner channel 530 and gap 525 is outer channel 535. Seals 540, such as O-rings, and sliding seals 335 seal the conductance pathway through the various layers penetrated by tubular member 305. In some embodiments, inner channel 530 comprises a helical or spiral channel 545 that includes portions formed on the outer surface of tubular member 305 and the inner surface of sleeve 520.

[0050]

[0054] The conductance pathway also flows through ports 555 formed in sleeve 520 that are in fluid communication with inner channel 530 and / or outer channel 535. The conductance pathway also extends into connector 300 via a plurality of longitudinal channels 560 that are in fluid communication with lower channel 365 of connector 300.

[0051]

[0055] As shown in Figure 5, both the first end 505 and the second end 510 of the tubular member 305 include a spring seal 385. The spring seal 385 includes a coil spring made from a metallic material, such as stainless steel. Also shown in Figure 5, both the first end 505 and the second end 510 of the tubular member 305 include an end guide 380.

[0052]

[0056] As shown in both Figures 3 and 5, connector 300 can be used in multiple locations. For example, according to the embodiment shown in Figure 3, connector 300 can be utilized at the interface between insulator plate 109 and ground plate 111. As yet another example, according to the embodiment shown in Figure 5, connector 300 can be utilized at the interface between ground plate 111 and sidewall 104 of chamber body 102 (Figure 1).

[0053]

[0057] The use of the described connectors and fluid conduits results in a substrate support assembly with better resistance to ohmic heating due to parasitic RF currents. This resistance also reduces current losses, allowing for reduced energy requirements for the process chamber. Furthermore, the improved thermal expansion coefficient of ceramic materials improves the fracture resistance of the connectors and fluid conduits.

[0054]

[0058] While the forgoing is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof, which scope is determined by the following claims.

Claims

1. 1. A semiconductor chamber component comprising: a power supply area; a ground area; a fluid conduit disposed within the semiconductor chamber component and passing through the power supply region and the ground region, the fluid conduit comprising a ceramic material; 1. A semiconductor chamber component comprising:

2. The semiconductor chamber component of claim 1 , wherein the ceramic material comprises zirconia.

3. The semiconductor chamber component of claim 1 further comprising a connector disposed at a boundary of the power feed region and the ground region.

4. The semiconductor chamber component of claim 3 , wherein the fluid conduit and the connector are the same material.

5. The fluid conduit is about 10 ４ Ω cm to about 10 １１ 10. The semiconductor chamber component of claim 1, having a volume resistivity of between ohm-cm.

6. When the connector and the fluid conduit are subjected to a bias frequency of about 2 MHz, the connector and the fluid conduit have a bias frequency of about 2.12 x 10 ４ 4. The semiconductor chamber component of claim 3 having an impedance of Ω.

7. The semiconductor chamber component of claim 1 , wherein the fluid conduit is disposed within a polytetrafluoroethylene sleeve.

8. The semiconductor chamber component of claim 1 , wherein the fluid conduit is a coolant conduit.

9. 10. The semiconductor chamber component of claim 1, wherein the fluid conduit has a thermal conductivity of between about 4 W / m·K and about 6 W / m·K.

10. 1. A substrate support assembly comprising: Equipment plate; an insulator plate disposed between the ground plate and the equipment plate; a fluid conduit disposed within the substrate support assembly through the facilities plate and the insulator plate; a connector coupled to the ground plate for receiving a portion of the fluid conduit, the connector comprising a central opening having an inner diameter of between about 0.7 inches and about 0.8 inches; A substrate support assembly comprising:

11. The substrate support assembly of claim 10 , wherein the fluid conduit and the connector are the same material.

12. The substrate support assembly of claim 11 , wherein the fluid conduits and the connectors are ceramic.

13. The volume resistivity of the fluid conduit is about 10 ４ Ω cm to about 10 １１ The substrate support assembly of claim 12 , wherein the resistance is between Ω·cm.

14. The substrate support assembly of claim 13 , wherein the connector further comprises a flange having a plurality of through holes.

15. The substrate support assembly of claim 10 , wherein the fluid conduit is disposed within a polytetrafluoroethylene sleeve.

16. The substrate support assembly of claim 10 , wherein the connector is disposed with and in contact with the ground plate.

17. When the connector and the fluid conduit are subjected to a bias frequency of about 13.56 MHz, the connector and the fluid conduit have a bias frequency of about 3.18 x 10 ３ The substrate support assembly of claim 10 having an impedance of Ω.

18. The substrate support assembly of claim 10 , wherein the connector and the fluid conduit have a coefficient of thermal expansion of between about 9 ppm / ° C. and about 10 ppm / ° C.

19. 1. A substrate support assembly comprising: Equipment plate; a ground plate coupled to the equipment plate; a fluid conduit disposed within the substrate support assembly through the facilities plate and the ground plate, the fluid conduit having an outer surface surrounded by a polytetrafluoroethylene sleeve; a connector coupled to the ground plate that receives a portion of the fluid conduit, the connector connecting a tubular member of the fluid conduit to the ground plate, the connector and the fluid conduit comprising the same ceramic material; A substrate support assembly comprising:

20. 20. The substrate support assembly of claim 19, wherein the connector further comprises an opening having a diameter of between about 0.7 inches and about 0.8 inches.

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