Fluid conduits and flanges for high bias applications

Abstract

Methods and apparatus for cooling a semiconductor chamber are described herein. A semiconductor chamber component includes an energization region; a ground region; and a fluid conduit disposed within the semiconductor chamber component and passing through the energization region and the ground region, the fluid conduit comprising a ceramic material.

Description

Technical Field

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 412,266, filed on September 30, 2022, the entire contents of which are incorporated herein by reference.

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

[0003] Reliably producing nanometer or smaller features is one of the key technical challenges for next generation very large scale integration (VLSI) and ultra-large-scale integration (ULSI) semiconductor components. However, the ever-shrinking dimensions of VLSI and ULSI interconnect technologies have placed additional demands on processing capabilities as the limits of circuit technology are pushed. Reliably forming gate structures on substrates is important to the success of VLSI and ULSI and to the ongoing efforts to increase circuit density and quality of individual substrates and wafers.

[0004] In order to reduce manufacturing costs, integrated chip (IC) manufacturers require higher throughput and better component yield and performance from each processed silicon substrate. Some manufacturing technologies currently being developed for next-generation components require processing at low temperatures. Dry reactive ion etching of substrates uniformly maintained at low temperatures allows ions to bombard the upward surface of the material disposed on the substrate with reduced spontaneous etching to form grooves with smooth, vertical sidewalls. In addition, the selectivity of etching one material relative to another can be improved at low temperatures. For example, the selectivity between silicon (Si) and silicon dioxide (SiO2) increases exponentially as the temperature decreases.

[0005] Operating a substrate support assembly to enable low temperature processing typically relies on the use of a coolant that is circulated through the substrate support assembly. Since the conduit used to route the coolant crosses both grounded and powered portions of the substrate support assembly, the coolant must be sufficiently electrically insulating to prevent electrical shorting of substrate support assembly components to ground. However, in higher bias power applications, the conduit may experience cracking due to the higher DC voltage and ohmic heating experienced during higher bias radio frequency (RF) power applications. In other words, in high bias power applications, the conduit may experience higher parasitic current losses, resulting in conduit cracking.

[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 coolant flowing at a low temperature is flowing through the conduit. A method and apparatus for cooling a semiconductor chamber are described herein according to one embodiment. A semiconductor chamber component includes a powered area; a grounded area; and a fluid conduit disposed within the semiconductor chamber component and passing through the powered area and the grounded area, the fluid conduit comprising a ceramic material. Summary of the invention

[0007] According to one embodiment, a method and apparatus for cooling a semiconductor chamber are described herein. A semiconductor chamber component includes a powered area; a grounded area; and a fluid conduit disposed in the semiconductor chamber component and passing through the powered area and the grounded area, the fluid conduit comprising a ceramic material.

[0008] In another embodiment, a substrate support assembly includes a facility plate; an insulator plate disposed between a ground plate and the facility plate; a fluid conduit disposed within the substrate support assembly and configured to pass through the facility plate and the insulator plate; and a connector coupled to the ground plate, the ground plate accommodating a portion of the fluid conduit, the connector including a central opening having an inner diameter between approximately 0.7 inches and approximately 0.8 inches.

[0009] In another embodiment, a substrate support assembly includes a facility plate; a ground plate coupled to the facility plate; a fluid conduit disposed within the substrate support assembly and disposed through the facility plate and the ground plate, the fluid conduit including an outer surface surrounded by a polytetrafluoroethylene sleeve; and a connector coupled to the ground plate housing 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to be able to understand the above-mentioned features of the present disclosure in detail, the present disclosure briefly summarized above may be more particularly described with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings only illustrate exemplary embodiments of the present disclosure and therefore should not be considered as limiting the scope thereof, as the present disclosure may allow other equally effective embodiments.

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

[0012] FIG. 2A to FIG. 2D is a schematic cross-sectional view of an exemplary plasma processing chamber.

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

[0014] Figure 4A and Figure 4B is a schematic diagram of a connector as disclosed herein.

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

[0016] To facilitate understanding, identical reference numerals have been used, where possible, to designate common elements among the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation. DETAILED DESCRIPTION

[0017] Embodiments described herein provide a substrate support assembly that enables cryogenic operation of an electrostatic chuck (ESC) such that a substrate disposed on the ESC is maintained at a cryogenic process temperature suitable for processing while other surfaces of the process chamber are maintained at different temperatures. Cryogenic process temperatures (i.e., the temperature of the substrate) are intended to refer to temperatures at the substrate support that are less than -10°C.

[0018] Also described herein is a substrate support assembly that includes one or more conduits for conveying fluid within the substrate support assembly between an energized portion and a grounded portion of the substrate support assembly that are less susceptible to arcing and rupture at high bias power levels. Because the conduits described herein are less susceptible to arcing and rupture at high bias power levels than conduits used in conventional substrate support assemblies, the reliability, maintenance intervals, and useful life of the substrate support assembly are significantly improved. Although the conduits are primarily described as being embodied in a substrate support assembly configured to enable cryogenic operation, the conduits may also be used in other substrate support assemblies or other semiconductor processing chamber components where fluid is conveyed in conduits that pass through grounded and energized portions of a processing chamber assembly.

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

[0020] The described substrate support assemblies can be used in various types of plasma processing chambers, such as etching chambers, physical vapor deposition chambers, chemical vapor deposition chambers, ion implantation chambers, plasma processing chambers, annealing chambers, etc., and other systems where it is necessary to process substrates maintained at cryogenic processing temperatures. However, it should be noted that the substrate support assemblies and chamber components described herein can be used at other processing temperatures.

[0021] Figure 1 1 is a cross-sectional schematic diagram of an exemplary plasma processing chamber 100 having a substrate support assembly 101. The described substrate support assembly 101 may be utilized in situations where the ability to uniformly maintain a surface or workpiece, such as a substrate 124, at a cryogenic processing temperature is desired. Dry reactive ion etching of a substrate 124 maintained at a cryogenic processing temperature enables ions to bombard an upward facing surface of a material disposed on the substrate 124 with reduced spontaneous etching, thereby forming a groove having smooth, vertical sidewalls. For example, ion diffusion in pores of a low-k dielectric material disposed on a substrate 124 uniformly maintained at a cryogenic processing temperature is reduced while ions continue to bombard the upward facing surface of the low-k dielectric material to form a groove having smooth, vertical sidewalls. In addition, the selectivity of etching one material relative to another material may be increased at cryogenic processing temperatures. For example, the selectivity between silicon (Si) and silicon dioxide (SiO2) increases exponentially as the temperature decreases.

[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 injection device 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 device 112 to allow process gases to be provided into the processing region 110. The injection device 112 may be one or more nozzles or inlets, or a showerhead. The process gases, along with any process byproducts, are removed from the processing region 110 through an exhaust port 116 formed in the sidewalls 104 or the bottom 106 of the chamber body 102. The exhaust port 116 is coupled to a pumping system 140 that includes a throttle valve and a pump for controlling the vacuum level within the processing region 110.

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

[0024] The substrate support assembly 101 is disposed below an implantation device 112 in a processing region 110. 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 a facility plate 107. The facility plate 107 supported by a ground plate 111 is configured to facilitate electrical, cooling, heating, and gas connections to the substrate support assembly 101. The ground plate 111 is supported by a bottom 106 of the processing chamber. An insulator plate 109 insulates the facility plate 107 from the ground plate 111. The ground plate 111 represents a grounded area of ​​the substrate support assembly 101. The ESC 103, the ESC base assembly 105, the facility plate 107, and the insulator plate 109 represent an energized area of ​​the substrate support assembly 101.

[0025] The ESC base assembly 105 includes a base channel 115 coupled to a cryogenic refrigerator 117. The cryogenic refrigerator 117 provides a base fluid (such as a refrigerant) to the base channel 115 so that the ESC base assembly 105 and thus the base plate 124 can be maintained at a predetermined low temperature. Similarly, the facility plate 107 includes a facility channel 113 coupled to a refrigerator 119. The refrigerator 119 provides a facility fluid to the facility channel 113 so that the facility plate 107 maintains a predetermined temperature. In one example, the base fluid maintains the ESC base assembly 105 at a temperature lower than the temperature of the facility plate 107.

[0026] Additional references Figure 2A , the cryogenic refrigerator 117 is in fluid communication with the substrate channel 115 through a substrate inlet conduit 123 connected to the inlet 254 of the substrate channel 115 and through a substrate outlet conduit 125 connected to the outlet 256 of the substrate channel 115, so that the ESC substrate assembly 105 is maintained at a predetermined low temperature. In one embodiment that may be combined with other embodiments described herein, the cryogenic refrigerator 117 is coupled to an interface box to control the flow rate of a base fluid. The base fluid comprises a composition that remains liquid at a low temperature below -50°C under operating pressure. The base fluid is typically insulated so that when the base fluid circulates through the substrate support assembly 101, an electrical path is not formed through the base fluid. Non-limiting examples of suitable facility fluids include fluorinated heat transfer fluids. The cryogenic refrigerator 117 provides a base fluid that circulates through the substrate channel 115 of the ESC substrate assembly 105. The base 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 so that the substrate 124 disposed on the ESC 103 is uniformly maintained at a cryogenic processing temperature. In one embodiment, which may be combined with other embodiments described herein, the cryogenic freezer 117 is operable to maintain the cryogenic temperature below about -50°C.

[0027] The freezer 119 is in fluid communication with the facility channel 113 through a facility inlet conduit 127 connected to an inlet 240 of the facility channel 113 and through a facility outlet conduit 129 connected to an outlet 242 of the facility channel so that the facility plate 107 maintains a predetermined ambient temperature. In one embodiment that may be combined with other embodiments described herein, the freezer 119 is coupled to an interface box to control the flow rate of a facility fluid. The facility fluid may include a material that can maintain an ambient temperature between about -10°C and about 60°C. The freezer 119 provides a facility fluid that circulates through the facility channel 113 of the facility plate 107. The facility fluid is typically insulated so that when the facility fluid circulates through the substrate support assembly 101, no electrical path is formed through the facility fluid. 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 maintain the insulator plate 109 at a predetermined ambient temperature.

[0028] Mainly return to Figure 1 , the ESC 103 has a support surface 130 and a bottom surface 132 opposite to the support surface 130. In one embodiment that can be combined with other embodiments described herein, the ESC 103 is made of a ceramic material, such as aluminum oxide (Al2O3), aluminum nitride (AlN), or other suitable materials. Alternatively, the ESC 103 can be made of a polymer, such as polyimide, polyetheretherketone, polyaryletherketone, etc.

[0029] The ESC 103 includes a clamping electrode 126 disposed therein. The clamping electrode 126 can be configured as a monopolar or bipolar electrode, or other suitable arrangement. The clamping electrode 126 is coupled to a clamping power supply 134 through an RF filter and a facility board 107, which provides DC power to electrostatically fasten the substrate 124 to a support surface 130 of the ESC 103. The RF filter prevents the RF power used to form a plasma (not shown) within the plasma processing chamber 100 from damaging electrical equipment or creating electrical hazards outside the chamber.

[0030] The ESC 103 includes one or more resistive heaters 128 embedded therein. 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 processing 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 supply 136 through a facility board 107 and an RF filter. The RF filter prevents the RF power used to form a plasma (not shown) within the plasma processing chamber 100 from damaging electrical equipment or causing electrical hazards outside the chamber. The heater power supply 136 can provide 500 watts or more of power to the resistive heaters 128. The heater power supply 136 includes a controller 138 for controlling the operation of the heater power supply 136, which is generally configured to heat the substrate 124 to a predetermined low temperature. In one embodiment that may be combined with other embodiments described herein, the resistive heater 128 includes a plurality of laterally separated heating zones, wherein the controller enables at least one zone of the resistive heater 128 to be preferentially heated relative to the resistive heaters 128 positioned in one or more other zones. For example, the resistive heaters 128 may be arranged concentrically in a plurality of separate heating zones. The resistive heaters 128 maintain the substrate 124 at a cryogenic processing temperature suitable for processing. In one embodiment that may be combined with other embodiments described herein, the cryogenic processing temperature is below about -10°C. For example, the cryogenic processing temperature is between about -10°C and about -150°C.

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

[0032] Ceramic refrigerant feed pipe

[0033] Return to reference Figure 2A , the exemplary substrate support assembly 101 is configured to enable low temperature operation of the ESC 103 so that the substrate 124 disposed on the substrate support assembly is maintained at a low temperature processing temperature. The ESC 103 is coupled to the ESC base assembly 105. In one embodiment that may be combined with other embodiments described herein, the ESC 103 is fastened 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 that may be combined with other embodiments described herein, the bonding layer 202 may include an epoxy resin or a metallic material. The clamping electrode 126 is coupled to the clamping power supply 134 via a first insulated wire 204, which is disposed through a first bore 212 in a lower insulator of the facility plate 107 and an upper insulator 214 of the ESC base assembly 105.

[0034] The facility plate 107 includes a plate portion 229 and a wall portion 230. The plate portion 229 of the ESC base assembly 105 is coupled to the facility plate 107 with one or more first screw assemblies such that a vacuum region 222 exists between the ESC base assembly 105 and the facility plate 107.

[0035] The facility plate 107 includes a wall portion 230 coupled to the ESC 103 by a seal 232. In one embodiment that may be combined with other embodiments described herein, the lower insulator of the facility plate 107 maintains a vacuum region 222 by the seal 232. The wall portion 230 coupled to the ESC by the seal 232 protects the material of the ESC base assembly 105 from potential corrosion and / or erosion caused by contact with the process gas. The vacuum region 222 is defined by the ESC 103, the ESC base assembly 105, the facility plate 107, and the seal 232. The vacuum region 222 prevents condensation on the back side of the cooling plate, prevents the process gas from entering the substrate support assembly 101 by having a pressure independent of the pressure of the process region 110, and provides thermal isolation between the ESC base assembly 105 and the facility plate 107. In one embodiment that may be combined with other embodiments described herein, the facility plate 107 includes an aluminum-containing material.

[0036] The facility channel 113 of the facility plate 107 is machined in the facility plate and sealed with a cover 238. In one example, the cover 238 is welded to the facility plate 107 to seal the facility channel 113. The inlet 240 of the facility channel 113 is in fluid communication with an inlet conduit 244 disposed through the insulator plate 109 and the ground plate 111. The outlet 242 of the facility 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 connection 248 having a connection inlet 250 connected to the facility inlet conduit 127 and a connection outlet 252 connected to the facility outlet conduit 129. In operation, the facility plate 107 is generally maintained in RF thermal conditions.

[0037] As discussed 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 between the powered facility plate 107 and the ESC base assembly 105 (i.e., the powered portions) and the grounded insulator plate 109 and the substrate support assembly 101 (i.e., the grounded portion of the substrate support assembly 101).

[0038] As shown in the enlarged portion of FIG. 2B , the conduit 244 includes a first end 291 and a second end 293. The conduit 244 also has an outer surface 295 connecting the first end 291 and the second end 293. As shown in FIG. 2C , the outer surface 295 at each of the ends 291, 293 includes a sealing surface 289. The sealing surface 289 is polished to promote sealing with the facility plate 107 and the connection 248. In one example, the outer surface 295 at each of the ends 291, 293 is polished to at least 32 μin Ra or smoother. A seal 297 may be disposed between the polished sealing surface 289 of the outer surface 295 and the facility plate 107 and the connection 248 to prevent leakage. In one example, the seal 297 may be configured generally as described with reference to the seal 232, or configured in another suitable manner.

[0039] Figure 2D Alternative sealing methods are illustrated. As shown in FIG. 2A', a fitting 299 can be sealingly coupled to an outer surface 295 at each of the ends 291, 293. The fitting 299 is configured to sealingly mate with a complementary mating surface (e.g., male / female threads, compression fittings, braze rings, etc.) of the facility plate 107 and / or the connection 248. In one example, the fitting 299 can be a metal cylinder brazed to the conduit 244 and to the facility plate 107 at one end 291, and a second fitting 299 brazed to the conduit 244 and to the connection 248 at the other end 293. Although the seal 297 is illustrated and described as a piston seal, the seal 297 can alternatively be configured as a face seal.

[0040] Return to reference Figure 2A, the substrate channel 115 of the ESC substrate assembly 105 includes an inlet 254 of the substrate channel 115, which is 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 substrate 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 an interface block 270. In one embodiment that may be combined with other embodiments described herein, the interface block 270 is made of 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. The interface block 270 includes a substrate inlet 272, a vacuum channel 276, a substrate outlet 274, and a vacuum channel 278. The substrate inlet 272 connects the fluid inlet conduit 266 to the substrate inlet conduit 123. The substrate outlet 274 connects the fluid outlet conduit 268 to the substrate outlet conduit 125. The vacuum channel 276 is connected to the vacuum conduit 280 in fluid communication with the vacuum source 284, and the vacuum channel 278 is connected to the vacuum conduit 282 in fluid communication with the vacuum source 284. Coupling the vacuum source 284 to the vacuum region 222 enables a pressure to be maintained in the vacuum region 222 that is independent of the pressure of the processing region 110. In one embodiment, which may be combined with other embodiments described herein, the fluid inlet conduit 266 and the fluid outlet conduit 268 are coupled to the ESC substrate assembly 105 through the seal 232 to maintain the pressure in the vacuum region 222.

[0041] The conduits 244, 246, 266, 268 may also be manufactured as described above, for example, with the ends described with reference to FIG. 2A′. The fluid conduits 244, 246, 266, 268 may also be configured with a cannula 520 (described in more detail below). Figure 5 ). The sleeve 520 is inserted into an electrically insulating backing tube which provides mechanical strength to the catheter and insulation from RF power.

[0042] Return to reference Figure 2A To prevent cracking during high bias power application, the conduits 244, 246, 266, 268 are made of a ceramic material. For example, the ceramic material may include zirconium dioxide, yttrium oxide, magnesium oxide, or any combination thereof. In another example, the ceramic material may be fired or sintered zirconium oxide, the fired or sintered zirconium oxide comprising 90% to 100% zirconium dioxide, 10% to 30% yttrium oxide, and 1% to 5% magnesium oxide by weight, or any combination thereof. In a non-limiting example, the ceramic material has a strength of about 10 4 Ω-cm to about 10 11The ceramic material has a desired volume resistivity in the Ω-cm range. The density of the ceramic material is about 6 g / cm. The elastic modulus of the ceramic material is about 192 GPa. The flexural strength of the ceramic material is about 1,000 MPa. The thermal conductivity of the ceramic material is between about 4 W / m°K and about 6 W / m°K, for example, about 5 W / m°K. The thermal expansion coefficient of the ceramic material is between about 9 ppm / °C and about 10 ppm / °C, for example, about 9.5 ppm / °C.

[0043] In other words, the fluid conduits 244, 246, 266, 268 may comprise a ceramic material selected to withstand higher DC voltages and RF power, such as at RF frequencies between about 2 MHz and about 13 MHz. When the fluid conduits are subjected to RF energy during processing, the conduits 244, 246, 266, 268 made of the ceramic material have matched impedance values, such that the impedance is matched to reduce parasitic current losses from the conduits 244, 246 to ground. The reduced parasitic current losses on the conduits 244, 246, 266, 268 allow more current to be delivered to the generated plasma and allow lower bias power levels to be used for high bias power applications. According to some embodiments, the matched fluid conduits 244, 246, 266, 268 further provide additional cooling capabilities because the matched fluid conduits 244, 246, 266, 268 may be cryogen conduits. Thus, preventing additional thermal energy from being imparted to the mating fluid conduits 244 , 246 , 266 , 268 enhances the cooling capabilities of the substrate support assembly 101 .

[0044] Thus, such configuration of the conduits 244, 246, 266, 268 prevents breakage under high bias RF power application, substantially preventing arcing between the conduits 244, 246, 266, 268 and grounded portions of the substrate support assembly 101, which advantageously increases reliability, maintenance intervals, and useful life of the substrate support assembly 101.

[0045] Reduced capacitance connector for high bias applications

[0046] Figure 3 2 is a cross-sectional view of a portion of the substrate support assembly 101 of FIG. The interface block 270 includes a connector 300 that facilitates coupling the conduits 244, 246, 266, 268 (only conduit 268 is shown for simplicity) to the substrate support assembly 101. In particular, the connector 300 couples the tubular members 305 of the conduits 244, 246, 266, 268 to the ground plate 111. For example, the fluid inlet conduit 266 (at Figure 3 ) and the fluid outlet conduit 268 include an interface block 270 having a connector 300 and a tubular member 305.

[0047] 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. Figure 3 In the cross-sectional view of FIG. 3 , only one fastener is shown, but up to about three fasteners may be used to couple the connector 300 to the ground plate 111. A portion of the ground plate 111 includes a recess 315 formed therein. Figure 3 315, only one recess is illustrated, but the number of recesses is equal to the number of fasteners utilized with the connector 300. A biasing assembly 320 coupled to the fastener 310 is positioned in the recess 315. The biasing assembly 320 includes a plurality of spring forms 325 that are biased relative to each other and relative to the fastener 310 and the recess 315. Each of the spring forms 325 compresses and expands based on the temperature of the substrate support assembly 101. For example, when a cryogen is provided to the substrate support assembly 101 (e.g., when the substrate support assembly 101 is refrigerated), the spring form 325 compresses. When the substrate support assembly 101 is not refrigerated, the spring form 325 expands. Thus, the biasing assembly 320 (one or a combination of the connector 300, the spring form 325, and the recess 315) allows the connector 300 to move at least vertically (in the Z direction) relative to the ground plate 111 during use. Each of the spring forms 325 may be a Belleville spring washer, such as a Belleville washer.

[0048] 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 the connector 300 to move vertically relative to the ground plate 111 during use and maintains a vacuum or negative pressure from the ambient pressure or atmospheric pressure. For example, a gap 345 formed between the outer surface of the tubular member 305 and the portion of the connector 300, the insulator plate 109 and the ground plate 111 along the length of the tubular member 305 is maintained under vacuum pressure during the use of the substrate support assembly 101. In contrast, the outer surface 350 of the connector 300 is in fluid communication with the surrounding or atmospheric conditions. Therefore, the sliding seal 335 includes an airtight seal that maintains pressure inside and outside the connector 300. In addition, 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.

[0049] The connector 300 is also coupled to the lower surface 355 of the ground plate 111 through a thermal gasket 360. The thermal gasket 360 is a thermally conductive gel material in the form of a pad. The thermal gasket 360 includes 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. Although Figure 3Only one of the lower channels 365 and one of the upper channels 370 is illustrated in the cross-sectional view of FIG, but the connector 300 may have three, four, or more of each of the lower channels 365 and 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, a negative pressure may be provided through the gap 345, which is facilitated by pumping through the lower channels 365 and the upper channels 370.

[0050] The tubular member 305 includes a passage 375 formed along its length for allowing the refrigerant to flow to the cryogenic refrigerators 117, 119. The tubular member 305 also includes an end guide 380 and a spring seal 385. As will be described below, Figure 5 As explained in , the tubular member 305 includes an end guide 380 and spring seals 385 at both ends of the end guide.

[0051] Figure 4A is a top view of a connector 300 according to some embodiments, and Figure 4B is a cross-sectional view of the connector. The connector 300 includes a central opening 400 sized to receive the tubular member 305 ( Figure 3 ). The central opening 400 includes an inner diameter 450, a first diameter 451, and a second diameter 452. The inner diameter 450 is the inner surface of the connector 300 and partially defines the gap 345. The inner diameter 450 is between about 0.7 inches and about 0.8 inches, for example, about 0.755 inches. The first diameter 451 is between about 0.9 inches and about 1.1 inches, for example, about 1 inch. The second diameter 452 is the diameter of the outer surface of the connector 300. The second diameter 452 is between about 0.9 inches and about 1.1 inches, for example, about 0.89 inches. In addition, the connector 300 also includes a flange 405. The flange 405 is a connecting portion of the connector 300, which enables the connector to be attached to a plate within the substrate support assembly 101. The flange 405 includes a plurality of through holes 410, each of which is suitable for receiving a fastener 310 ( Figure 3 ). The connector 300 also includes an upper shoulder 415 and a second or lower shoulder 420. An annular recess 330 is defined between the upper shoulder 415 and the lower shoulder 420. The annular recess includes an elastomeric seal 340 to seal the connector 300 when it is attached within the substrate support assembly 101.

[0052] 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 high bias power applications, 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 zirconium oxide, the fired or sintered zirconium oxide comprising 90% to 100% zirconium dioxide, 10% to 30% yttrium oxide, and 1% to 5% magnesium oxide by weight, or any combination thereof. In one non-limiting example, the ceramic material has a strength of about 10 4 Ω-cm to about 10 11 The desired volume resistivity in the Ω-cm range. The density of the ceramic material is about 6 g / cm. The elastic modulus of the ceramic material is about 192 Gpa. The flexural strength of the ceramic material is about 1,000 MPa. The thermal conductivity of the ceramic material is between about 4 W / m°K and about 6 W / m°K, for example, about 5 W / m°K. The thermal expansion coefficient of the ceramic material is between about 9 ppm / °C and about 10 ppm / °C, for example, about 9.5 ppm / °C. The inventors have found that when the inner diameter 450 of the connector 300 made of the ceramic material is less than about 0.8 inches, the conduit impedance of each of the fluid conduits 244, 246, 266, 268 is less than 1000 Ω. In addition, when the connector and the fluid conduits 244, 246, 266, 268 are subjected to RF bias, the overall assembly including the connector 300 and a single fluid conduit of the fluid conduits 244, 246, 266, 268 has a lower assembly impedance. For example, when the connector 300 and the fluid conduit 268 are subjected to a bias frequency of about 20 Hz, the assembly impedance of the assembly is about 1.5×10 8 Ω. For example, when the connector 300 and the fluid conduit 268 experience a bias frequency of about 2 MHz, the component impedance of the assembly is about 2.12×10 4 Ω. For example, when the connector 300 and the fluid conduit 268 experience a bias frequency of about 13.56 MHz, the component impedance of the assembly is about 3.18×10 3 Ω.

[0053] Figure 5 1 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 is composed of Figure 5. The vacuum path 500 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 flowing through the opening 515 in the end guide 380 to reach the gap 345. In some embodiments, a portion of the outer surface of the tubular member 305 includes a sleeve 520. The sleeve 520 can 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, the ESC base assembly 105, the insulator plate 109 and the ground plate 111. The sleeve 520 can surround the outer surface of the tubular member 305. The sleeve 520 can extend between the ESC 103 and the second end 510 of the tubular member 305. The sleeve 520 advantageously isolates the RF heat ESC 103 from the ground, thereby preventing the tubular member 305 from rupturing.

[0054] In addition, the sleeve 520 increases the resistance of the tubular member 305 relative to the ground. In turn, this reduces the parasitic current losses of the tubular member 305, which reduces the ohmic heating of the tubular member 305. In other words, the sleeve 520 isolates the tubular member from the cryogenic temperatures on one side of the chamber and the RF high temperatures on the other side of the chamber. The sleeve 520 reduces the thermal energy experienced by the tubular member 305 due to the temperature difference and prevents cracking.

[0055] In some embodiments, gap 345 is an inner channel 530 and gap 525 is an outer channel 535. Seals 540, such as O-rings, and sliding seals 335 seal the conductive paths through the various layers through which tubular member 305 extends. In some embodiments, inner channel 530 includes a spiral or helical channel 545 that includes portions formed in the outer surface of tubular member 305 and the inner surface of sleeve 520.

[0056] The conductive path also flows through ports 555 formed in sleeve 520 that are in fluid communication with internal passage 530 and / or external passage 535. The conductive path also extends into connector 300 through a plurality of longitudinal passages 560 that are in fluid communication with lower passage 365 of connector 300.

[0057] like Figure 5 As shown, the first end 505 and the second end 510 each include a spring seal 385. The spring seal 385 includes a coil spring made of a metal material (such as stainless steel). Figure 5 As shown, both the first end 505 and the second end 510 of the tubular member 305 include an end guide 380 .

[0058] like Figure 3 and Figure 5As shown, connector 300 can be used in a variety of positions. Figure 3 In the illustrated embodiment, the connector 300 may be utilized at the interface between the insulator plate 109 and the ground plate 111. In yet another example, according to Figure 5 In the embodiment shown in FIG. 1 , the connector 300 may be used at the interface between the ground plate 111 and the side wall 104 of the chamber body 102 ( Figure 1 ).

[0059] The use of the described connectors and fluid conduits has resulted in a substrate support assembly having better resistance to ohmic heating due to parasitic RF currents. The resistance also reduces current losses, thereby enabling a reduction in the energy requirements of the processing chamber. In addition, due to the increased coefficient of thermal expansion of the ceramic material, the connectors and fluid conduits have better resistance to fracture.

[0060] While the foregoing is directed to examples of the present disclosure, other and further examples of the disclosure may be devised without departing from the basic scope of the disclosure, and the scope of the disclosure is determined by the claims that follow.

Claims

1. A semiconductor chamber component, comprising: Power supply area; grounding area, and A fluid conduit is disposed in the semiconductor chamber component and passes through the powered area and the grounded area, wherein the fluid conduit comprises a ceramic material. 2 . The semiconductor chamber component of claim 1 , wherein the ceramic material comprises zirconium oxide. 3 . The semiconductor chamber component according to claim 1 , further comprising a connector disposed at an interface between the power supply area and the ground area. The semiconductor chamber component of claim 3 , wherein the fluid conduit and the connector are of the same material.

5. The semiconductor chamber component of claim 1, wherein the volume resistivity of the fluid conduit is about 10 4 Ω-cm to about 10 11 Between Ω-cm.

6. The semiconductor chamber component of claim 3, wherein when the connector and the fluid conduit are subjected to a bias frequency of about 2 MHz, the impedance of the connector and the fluid conduit is 2.12×10 4 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 cryogen conduit.

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

10. A substrate support assembly comprising: Facilities Board; an insulator plate disposed between the ground plate and the facility plate; a fluid conduit disposed within the substrate support assembly, the substrate support assembly disposed through the facility plate and the insulator plate; and A connector is coupled to the ground plate, the ground plate receiving a portion of the fluid conduit, the connector including a central opening having an inner diameter between about 0.7 inches and about 0.8 inches.

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

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

13. The substrate support assembly of claim 12, wherein the volume resistivity of the fluid conduit is about 10 4 Ω-cm to about 10 11 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 in contact with the ground plate.

17. The substrate support assembly of claim 10, wherein when the connector and the fluid conduit are subjected to a bias frequency of approximately 13.56 MHz, the impedance of the connector and the fluid conduit is 3.18×10 3 Ω.

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

19. A substrate support assembly comprising: Facilities Board; a ground plate coupled to the facility plate; a fluid conduit disposed within the substrate support assembly and disposed through the device plate and the ground plate, the fluid conduit comprising an outer surface surrounded by a polytetrafluoroethylene sleeve; as well as A connector is coupled to the ground plate, the ground plate receiving a portion of the fluid conduit, the connector coupling a tubular member of the fluid conduit to the ground plate, the connector and the fluid conduit comprising the same ceramic material.

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

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