Substrate support assembly with arc resistant coolant conduit

Abstract

Semiconductor chamber components are described herein, the semiconductor chamber components including one or more conduits for carrying a fluid between a powered portion and a grounded portion of the chamber component, the conduits being configured to be less susceptible to arcing than conventional components. In one example, a semiconductor chamber component is provided, the semiconductor chamber component including: a powered region, a grounded region, and a fluid conduit. The fluid conduit is disposed within the semiconductor chamber component and passes through the powered region and the grounded region. The fluid conduit has an end-to-end resistance between 0.1 MΩ and 100 MΩ.

Description

[0001] background

[0002] field

[0003] Embodiments of the present disclosure relate generally to semiconductor chamber components and, more particularly, to substrate support assemblies having arc resistant coolant conduits. Background Art

[0004] Reliably producing nanometer and smaller features is one of the key technical challenges for the next generation of very large scale integration (VLSI) and ultra large scale integration (ULSI) of semiconductor devices. However, the ever-shrinking dimensions of VLSI and ULSI internal connection technologies place 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 the quality of individual substrates and dies.

[0005] In order to reduce manufacturing costs, integrated chip (IC) manufacturers require higher throughput and better device yield and performance for each silicon substrate processed. Some manufacturing technologies for next-generation devices that are being explored in current development require processing at low temperatures. Dry reactive ion etching substrates uniformly maintained at low temperatures enable ions to bombard the upward-facing surface of the material disposed on the substrate with reduced spontaneous etching, thereby forming grooves with smooth, vertical sidewalls. In addition, the selectivity of etching one material relative to another can be improved at low temperatures. For example, as the temperature decreases, the selectivity between silicon (Si) and silicon dioxide (SiO2) increases exponentially.

[0006] Operating a substrate support assembly to achieve cryogenic 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 spans both grounded and powered portions of the substrate support assembly, the coolant must have sufficient electrical insulation to prevent short circuits. However, the flow of coolant within the insulated conduit can cause a charge to accumulate on the conduit over time that is sufficient to cause an arc between the conduit and the grounded portion of the substrate support assembly. The arc can cause or contribute to a number of problems, including the formation of pinholes in the conduit that undesirably allow coolant to leak out.

[0007] Therefore, there is a need for an improved substrate support assembly. Summary of the invention

[0008] Semiconductor chamber components are described herein that include one or more conduits for carrying a fluid between an energized portion and a grounded portion of the chamber component that are configured to be less susceptible to arcing than conventional components.

[0009] In one example, a semiconductor chamber component is provided, the semiconductor chamber component comprising: a powered region, a grounded region, and a fluid conduit. The fluid conduit is disposed in the semiconductor chamber component and passes through the powered region and the grounded region. The fluid conduit has an end-to-end resistance between 0.1 MΩ and 100 MΩ (such as 1.0 MΩ to 20 MΩ).

[0010] In another example, a semiconductor chamber component is disclosed as a substrate support assembly. The substrate support assembly includes: an electrostatic chuck (ESC), an ESC base assembly, a ground plate, and a first fluid conduit. The ESC has a support surface and a bottom surface opposite to the support surface. The ESC additionally has an adsorption electrode. The ESC base assembly supports the ESC, and the ESC base assembly has a substrate channel. At least one of the ESC and the ESC base assembly includes a powered area of ​​the substrate support assembly. The powered area of ​​the substrate support assembly is configured to receive RF power during a substrate processing operation. The ground plate supports the ESC base assembly. The first fluid conduit passes through the powered area and the ground plate. The first fluid conduit has an end-to-end resistance between 0.1 MΩ and 100 MΩ (such as 1.0 MΩ to 20 MΩ).

[0011] In yet another example, a substrate support assembly is provided, the substrate support assembly comprising: an electrostatic chuck (ESC), an ESC base assembly, a ground plate, and a first fluid conduit and a second fluid conduit. The ESC has a support surface and a bottom surface opposite the support surface. The ESC also has an adsorption electrode and a heater. The ESC base assembly supports the ESC and has a substrate channel. The ESC base assembly is configured to be RF powered during substrate processing operations. The ground plate supports the ESC base assembly. The first fluid conduit and the second fluid conduit extend from the ground plate to the substrate channel. The first fluid conduit provides an inlet for allowing a heat transfer fluid to flow into the substrate channel, while the second fluid conduit provides an outlet for the heat transfer fluid to flow out of the substrate channel. The first fluid conduit and the second fluid conduit are made of partially conductive ceramic and have an end-to-end resistance between 0.1 MΩ and 100 MΩ (such as 1.0 MΩ to 20 MΩ). BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order that the manner in which the above-mentioned features of the present disclosure can be understood in detail, the present disclosure briefly summarized above can be described in more detail by reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings illustrate only exemplary embodiments and are therefore not to be considered as limiting the scope thereof and may allow for other equally effective embodiments.

[0013] Figure 1 is a schematic cross-sectional view of an exemplary plasma processing chamber according to an embodiment.

[0014] Figure 2Ais a cross-sectional schematic diagram of an exemplary substrate support assembly according to an embodiment.

[0015] Figure 2A ' is set in Figure 2A A partial cross-sectional schematic diagram of an alternative example of a tube in a substrate support assembly is illustrated in FIG.

[0016] Figure 2B is a cross-sectional schematic diagram of an exemplary substrate support assembly according to an embodiment.

[0017] Figure 2C is a schematic diagram of a screw assembly according to an embodiment.

[0018] Figure 3 is a schematic diagram of a seal according to an embodiment.

[0019] 4A to 4D is a schematic cross-sectional view of an ESC substrate assembly according to an embodiment.

[0020] Figure 4E is a schematic cross-sectional view of a peripheral portion of an exemplary substrate support assembly according to an embodiment.

[0021] FIG. 5A to FIG. 5C is a cross-sectional, cross-sectional schematic diagram of an exemplary substrate support assembly according to an embodiment.

[0022] Figure 5D is a schematic cross-sectional view of a cryogenic optical probe assembly according to an embodiment.

[0023] Figure 6 is a schematic cross-sectional view of a semiconductor chamber component having an internal conduit spanning grounded and powered areas of the chamber component.

[0024] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation. DETAILED DESCRIPTION

[0025] Embodiments described herein provide a substrate support assembly that enables cryogenic operation of an electrostatic chuck (ESC) such that a substrate disposed on the electrostatic chuck is maintained at a cryogenic processing temperature suitable for processing while other surfaces of the processing chamber are maintained at a different temperature. The cryogenic processing temperature (i.e., the temperature of the substrate) is intended to refer to a temperature at the substrate support that is less than -10 degrees Celsius.

[0026] Also described herein is a substrate support assembly that includes one or more conduits for carrying a fluid within the substrate support assembly between an energized portion and a grounded portion of the substrate support assembly, the one or more conduits being less prone to arcing. Because the conduits described herein are less prone to arcing than conduits used in conventional substrate support assemblies, the reliability, service life, and useful life of the substrate support assembly are significantly improved. Although the arc-resistant conduits are primarily described as being embodied in substrate support assemblies configured to enable cryogenic operation, the arc-resistant conduits may also be used in other substrate support assemblies or other semiconductor processing chamber components where a fluid is conveyed in a conduit passing through a grounded portion and an energized portion of a processing chamber component.

[0027] Although the substrate support assembly is described below in the context of an etch processing chamber, the substrate support assembly may be used in other types of plasma processing chambers, such as physical vapor deposition chambers, chemical vapor deposition chambers, ion implantation chambers, etc., and other systems where it is desirable to process substrates that maintain cryogenic processing temperatures. However, it should be noted that the substrate support assembly and chamber components described herein may be used for other processing temperatures.

[0028] Figure 1 1 is a cross-sectional schematic diagram of an exemplary plasma processing chamber 100, which is shown as being configured as an etching 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, annealing chambers, physical vapor deposition chambers, chemical vapor deposition chambers, and ion implantation chambers, among others, as well as other systems 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 the substrate 124 maintained at a cryogenic processing temperature enables ions to bombard an upwardly facing surface of a material disposed on the substrate 124 with reduced spontaneous etching, such that a groove having smooth, vertical sidewalls is formed. For example, when ions continuously bombard an upwardly facing surface of a low-k dielectric material to form a groove having smooth, vertical sidewalls, ion diffusion in pores of the low-k dielectric material disposed on the substrate 124 uniformly maintained at a cryogenic processing temperature is reduced. Additionally, at cryogenic processing temperatures, the selectivity of etching one material relative to another can be improved. For example, as the temperature decreases, the selectivity between silicon (Si) and silicon dioxide (SiO2) increases exponentially.

[0029] The plasma processing chamber 100 includes a chamber body 102 having sidewalls 104, a bottom 106, and a lid 108 that enclose 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 inlet ports, or alternatively a showerhead. The process gases and any process byproducts are removed from the processing region 110 via 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.

[0030] The process gas may be energized to form a plasma within the process region 110. The process gas may be energized by capacitively coupling or inductively coupling RF power to the process gas. In embodiments that may be combined with other embodiments described herein, such as Figure 1 As depicted in , 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 via a matching circuit 120 .

[0031] The substrate support assembly 101 is disposed in the processing region 110 below the injection device 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 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 the bottom 106 of the processing chamber. An insulator plate 109 insulates the facility plate 107 from the ground plate 111.

[0032] The ESC substrate assembly 105 includes a substrate channel 115 coupled to a cryocooler 117 (at Figures 4A to 4D 105). The cryocooler 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 cooler 119 (at Figure 2A and 2B 107 ). The cooler 119 provides facility fluid to the facility channel 113 so 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 higher than the temperature of the facility plate 107 .

[0033] See also Figures 2A to 2B, the cryocooler 117 is in fluid communication with the substrate channel 115 via a substrate inlet conduit 123 connected to the inlet 254 of the substrate channel 115 and via 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 can be combined with other embodiments described herein, the cryocooler 117 is coupled to the interface box to control the flow rate of the substrate fluid. The substrate fluid includes a component that remains liquid at a low temperature of less than -50 degrees Celsius under operating pressure. The substrate fluid is typically insulated so that an electrical path through the substrate fluid is not formed when circulating through the substrate support assembly 101. Non-limiting examples of suitable facility fluids include fluorinated heat transfer fluids. The cryocooler 117 provides a substrate fluid that circulates 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 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 cryocooler 117 is operable to maintain the cryogenic temperature at less than about -50 degrees Celsius.

[0034] The cooler 119 is in fluid communication with the facility channel 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 maintains a predetermined ambient temperature. In one embodiment that may be combined with other embodiments described herein, the cryocooler 119 is coupled to the interface box to control the flow rate of the facility fluid. The facility fluid may include a material that can be maintained at an ambient temperature between about -10 degrees Celsius and about 60 degrees Celsius. The cooler 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 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 insulator plate 109 at a predetermined ambient temperature.

[0035] Main Return 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.

[0036] The ESC 103 includes an adsorption electrode 126 disposed in the ESC 103. The adsorption electrode 126 can be configured as a monopolar or bipolar electrode, or other suitable arrangement. The adsorption electrode 126 is coupled to an adsorption power supply 134 through an RF filter and a facility board 107, and the adsorption power supply 134 provides DC power to electrostatically fix the substrate 124 to the 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.

[0037] 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 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 creating 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 (not shown) for controlling the operation of the heater power supply 136, which is generally set 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 located 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 less than about -10 degrees Celsius. For example, the cryogenic processing temperature is between about -10 degrees Celsius and about -150 degrees Celsius.

[0038] The substrate support assembly 101 may include one or more temperature probe assemblies disposed in the substrate support assembly 101. One or more temperature assemblies 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 so that a desired substrate processing temperature may be maintained.

[0039] exist FIG. 5A to FIG. 5D100 is shown in FIG. 100 , which is coupled to a probe controller 138 and which may be combined with other embodiments described herein. In one embodiment, which may be combined with other embodiments described herein, a probe tip 516 of each of the cryogenic optical probes 512 is disposed in a surface of the ESC 103 (e.g., Figure 5B ) or at the surface of ESC103 (as shown in Figure 5A ) to determine the temperature of the ESC 103. In another embodiment that may be combined with other embodiments described herein, the probe tip 516 of each of the cryogenic optical probes 512 is disposed in the ESC base assembly 105 (as shown in FIG. Figure 5C ) to infer the temperature of the substrate based on the temperature of the ESC base assembly 105. In one embodiment that may be combined with other embodiments described herein, each of the cryogenic optical probe assemblies 500 (only one of which is shown) corresponds to a zone of a plurality of laterally separated heating zones of the resistive heater 128, wherein the cryogenic optical probe measures the temperature of each zone of the ESC 103. The probe controller 138 is coupled to the heater power supply 136 so that each zone of the resistive heater 128 is independently heated based on the temperature measurement, making the lateral temperature distribution of the ESC 103 substantially uniform, thereby allowing the substrate 124 disposed on the ESC 103 to be uniformly maintained at the cryogenic processing temperature.

[0040] Return to reference Figure 2A and Figure 2B , the exemplary substrate support assembly 101 is configured to enable the ESC 103 to perform low temperature operation so that the substrate 124 disposed thereon 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 fixed to the ESC base assembly 105 using 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 metal material. The adsorption electrode 126 is coupled to the adsorption power supply 134 via a first insulated wire 204, and the first insulated wire 204 is disposed through a first hole 208 in a lower insulator 212 of the facility plate 107 and an upper insulator 214 of the ESC base assembly 105. The one or more resistive heaters 128 are coupled to the heater power supply 136 via a second insulated wire 206 disposed through a second hole 210 in a lower insulator 212 of the facility plate 107 and an upper insulator 214 of the ESC base assembly 105 .

[0041] 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 using one or more first screw assemblies 220 so that a vacuum region 222 is present between the ESC base assembly 105 and the facility plate 107. Each of the one or more first screw assemblies 220 includes a bolt 224 that is inserted through a thermal break 227, a biasing element 226, and the facility plate 107 in contact with the facility plate 107 and inserted into a threaded hole 228 of the ESC base assembly 105. The thermal break 227 is in contact with the facility plate 107 to provide thermal isolation from the ESC base assembly 105 maintained at a low temperature. In one embodiment that may be combined with other embodiments described herein, the thermal break 227 includes a material containing polyamide-imide (PAI) or polyimide (PI). The biasing element 226 is used to generate a force when compressed. Suitable biasing elements 226 include coil springs, spring forms, and elastomers. In one example, the biasing element 226 is illustrated as a plurality of Belleville washers. By tightening the bolts 224 to compress the biasing element 226, the facility plate 107 is forced (ie, preloaded) against the ESC base assembly 105. In some embodiments, as Figure 2C , the screw cover 261 is coupled to the facility plate 107 on the bolt 224 so that a vacuum insulation region 263 is maintained between each of the one or more first screw assemblies 220. The screw cover 261 is coupled to the facility plate 107 through a seal 267 to maintain pressure in the vacuum insulation region 263 and thermally insulate each of the one or more first screw assemblies 220 from the facility plate 107. In operation, the ESC base assembly 105 is typically maintained in an RF heat state.

[0042] 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 212 of the facility plate 107 maintains a vacuum region 222 via 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 contact with the process gas to avoid potential corrosion and / or erosion. 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 by having a pressure independent of the pressure of the process region 110, prevents process gases from entering the substrate support assembly 101, 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.

[0043] A cover 238 is machined in the facility plate and used to seal the facility channel 113 of the facility plate 107. In one example, the cover 238 is welded to the facility plate 107 to seal the facility channel 113. An 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. An 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 typically maintained in an RF hot state.

[0044] 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 between the powered facility plate 107 and the ESC base assembly 105 (i.e., the powered portions) and the grounded insulator plate 109 and substrate support assembly 101 (i.e., the grounded portions) of the substrate support assembly 101. In order to prevent static charge from accumulating on the conduits 244, 246 while insulating facility fluid is passing through the conduits 244, 246, the conduits 244, 246 are made sufficiently conductive so that static charge sufficient to cause an arc within the substrate support assembly 101 does not accumulate on the surfaces of the conduits 244, 246, while still preventing a short circuit between the grounded and powered portions of the substrate support assembly 101 (here, the insulator plate 109 and the substrate support assembly 101). Thus, this configuration of the conduits 244, 246 substantially prevents arcing between the grounded portions of the conduits 244, 246 of the substrate support assembly 101, which advantageously increases the reliability, service life, and useful life of the substrate support assembly 101. In one example that may be combined with other examples described herein, the conduit 244 is made of a material that is compatible with the facility fluid and has an end-to-end resistance between about 0.1 megohms and about 100 megohms. For example, the end-to-end resistance of the conduit 244 may be between about 1.0 megohms and about 50 megohms, such as between about 1.0 megohms and about 20 megohms. Non-limiting examples of materials suitable for making the conduit 244 include materials such as SiC, Ti-doped alumina, carbon-doped plastics, and metal-doped ceramics.

[0045] like Figure 2AAs shown in the enlarged portion of , the conduit 244 includes a first end 291 and a second end 293. The conduit 244 also has an outer surface 295 connecting the connections 291, 293. The outer surface 295 at each of the ends 291, 293 includes a sealing surface 289. The sealing surface 289 is polished to facilitate 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 micro-inches RA or smoother, such as between about 4 micro-inches RA and 8 micro-inches RA. 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 as described with reference to the seal 232, or in another suitable manner. Alternatively, the fitting 299 (such as Figure 2A ' shown) can be sealingly coupled to the 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 thread, compression fitting, braze ring, etc.) of the facility plate 107 and / or the connection 248. In one example, the fitting 299 can be a metal cylinder that is brazed to the conduit 244 and to the facility plate 107 at one end 291, while the second fitting 299 is 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.

[0046] The conduits 246, 266, 268 may also be manufactured as described above, for example with Figure 2A The conduits 244, 246, 266, 268 may also be configured as sleeves inserted into an electrically insulating liner that provides mechanical strength to the conduits.

[0047] Also as indicated above and in Figure 6As schematically illustrated in , other semiconductor chamber components 600 (such as showerheads, electrostatic chucks, gas distribution plates, thermal shields, and removable processing kits) other than substrate support components having an internal conduit 602 passing between a grounded region 604 and a powered region 606 can have the conduit 602 manufactured as described herein with reference to the conduit 244. The powered region 606 is configured to utilize the semiconductor chamber component 600 during substrate processing in the processing chamber by applying power, such as DC and / or RF heat, for example, via a power supply 610, or via exposure to a plasma within the processing chamber. The grounded region 604 and the powered region 606 can optionally be separated by an insulating layer 608. The insulating layer 608 can be a polymer layer, a ceramic layer, a bonding layer, or other non-conductive suitable layer. In one example, the grounded region 604 is configured similar to the ground plate 111, while the powered region 606 is configured as a facility plate 107 or an ESC base assembly 105 or an ESC 103.

[0048] The conduit 602 is coupled to two channels 612, 614. The channels 612, 614 may be internally confined within the regions 604, 606, such as heat transfer fluid conduits, or may be exposed to the exterior of the component 600, such as gas flow holes disposed through the component 600. In one example, the channel 612 is coupled to a fluid source 616, such as a gas panel, a backside gas source, a process gas source, a purge gas source, or a heat transfer fluid source.

[0049] return FIG. 2A to FIG. 2B ,exist 4A to 4DThe substrate channel 115 of the ESC substrate assembly 105 described in more detail in the EMSC substrate assembly 105 includes an inlet 254 of the substrate channel 115, which is in fluid communication with a jacket 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 jacket outlet conduit 260 disposed through the facility plate 107, the insulator plate 109, and the ground plate 111. The jacket inlet conduit 258 and the jacket 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 jacket inlet conduit 258 includes a fluid inlet conduit 266 and a vacuum channel 262. The jacket 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 in 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.

[0050] The substrate support assembly 101 also includes one or more lift pin assemblies 286 for accommodating lift pins (not shown) for raising the substrate 124 above the support surface 130 of the ESC 103 to facilitate robotic transfer in 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 insulator plate 109, and the ground plate 111. A portion 290 of the lift pin guide 288 disposed through the ESC base assembly 105 is surrounded by a threaded bushing 292 to maintain the lift pin guide 288 in place. The lift pin guide 288 is coupled to the ESC 103 through a seal 232 to keep the chamber vacuum and the insulating vacuum separated. In one embodiment, which may be combined with other embodiments described herein, the ESC 103 includes one or more gas passages for providing a backside heat transfer gas, such as helium, to the interstitial space defined between the base plate 124 and the support surface 130 of the ESC 103. Each of the one or more gas passages is disposed through the ESC 103, the ESC base assembly 105, the facility plate 107, the insulator plate 109, and the ground plate 111. Each of the one or more gas passages is coupled to the ESC 103 through a seal 232 to maintain pressure in the vacuum region 222.

[0051] like Figure 2B , the facility plate 107 includes a recessed portion 296 and a seal 294 disposed between the insulator plate 109 and the facility plate 107. A surface 205 of the insulator plate 109 coupled to the facility plate 107 is conformal to the facility plate 107. The recessed portion 296 and the insulator plate 109 provide a reduced thickness 201 of the facility plate 107 and an increased thickness 203 of the insulator plate 109. In one embodiment, which may be combined with other embodiments described herein, an outer portion 269 of the insulator plate 109 includes a material that is different from a material of an inner portion 271 of the insulator plate 109. The outer portion 269 may include a material including aluminum oxide (AlO2) and the inner portion 271 of the insulator plate 109 may include a material including polystyrene.

[0052] Figure 3 is a schematic diagram of a seal 232 according to an embodiment. Figure 3While seal 232 is shown as a face seal, embodiments described herein may include a piston (i.e., radial) seal having a polytetrafluoroethylene (PTFE) body, a metal seal, or other suitable seal. Seal 232 may be an elastomeric or metal seal suitable for cryogenic use. Seal 232 may additionally include a biasing element (such as a spring or spring form) to energize seal 232 so that seal 232 maintains sufficient compression for robust cryogenic operation as described herein. Seal 232 described herein provides for sealing vacuum region 222 at temperatures between about -260 degrees Celsius and about 290 degrees Celsius. As Figure 3 As shown in , the seal 232 includes a PTFE body 302 having a spring 304 disposed therein. In one embodiment that may be combined with other embodiments described herein, the spring 304 may be made of a material including stainless steel, a nickel alloy, a nickel-chromium alloy, a cobalt-chromium-nickel-molybdenum alloy, or other suitable spring materials. The seal 232 allows the ESC 103 to be sealed at low temperatures. In one example, the seal 232 includes a PTFE body 302 and a spring 304 disposed therein, and has a safe operating range between about -260 degrees Celsius and about 290 degrees Celsius.

[0053] Figure 4A and Figure 4B is a cross-sectional schematic diagram of an ESC substrate assembly 105 having an ESC substrate 402 coupled to a substrate channel plate 404. The ESC substrate 402 includes a material that substantially matches the coefficient of thermal expansion of the ESC 103. The ESC substrate 402 may include a material containing molybdenum or carbon fiber. In one embodiment that may be combined with other embodiments described herein, the substrate channel plate 404 is composed of an aluminum-containing material. The substrate channel plate 404 includes a substrate channel 115 of the ESC substrate assembly 105. The substrate channel 115 is machined in the substrate channel plate 404 and a cover 420 is used to join, weld or braze the substrate channel 115. The inlet 254 of the substrate channel 115 is in fluid communication with the jacket inlet conduit 258, and the outlet 256 of the substrate channel 115 is in fluid communication with the jacket outlet conduit 260. The ESC substrate 402 is coupled to the substrate channel plate 404 via one or more second screw assemblies 408. In one embodiment, as Figure 4A As shown in FIG. 4 , the ESC substrate 402 is coupled to the substrate channel plate 404 using a thermally conductive pad 406 therebetween to maintain a defined thermal conductivity between the ESC substrate 402 and the substrate channel plate 404. In another embodiment, as shown in FIG. Figure 4B, the thermally conductive pad 406 is not included. Each of the one or more second screw assemblies 408 includes a bolt 410 that is inserted through one or more Belleville washers 412 and the ESC substrate 402 and into a threaded hole 414 of the ESC substrate 402. The one or more Belleville washers 412 and the bolts 410 are preloaded so that the substrate channel plate 404 is forced against the ESC substrate 402.

[0054] Figure 4C 4 is a cross-sectional schematic diagram of an ESC substrate assembly 105 having an ESC substrate 402 with a substrate channel 115. The ESC substrate 402 includes a material containing molybdenum or carbon fiber to substantially match the coefficient of thermal expansion of the ESC 103. The substrate channel 115 is machined in the ESC substrate 402 and joined, welded, or brazed using a cap 420. The inlet 254 of the substrate channel 115 is in fluid communication with a jacket inlet conduit 258, and the outlet 256 of the substrate channel 115 is in fluid communication with a jacket outlet conduit 260.

[0055] Figure 4D 1 is a cross-sectional schematic diagram of an ESC substrate assembly 105 having an ESC substrate 402 with a substrate channel 115. The ESC substrate 402 includes a material including molybdenum or carbon fiber to substantially match the coefficient of thermal expansion of the ESC 103. The substrate channel 115 is a coil 416 disposed in a space 424 machined in the ESC substrate 402. The inlet 254 of the substrate channel 115 is in fluid communication with a jacket inlet conduit 258, and the outlet 256 of the substrate channel 115 is in fluid communication with a jacket outlet conduit 260.

[0056] Figure 4E yes Figure 2B Schematic diagram of a cross-sectional view of a peripheral portion of a substrate support assembly 101 of the present invention. The ESC substrate 402 includes a groove 426 exposed to the vacuum region 222. The groove 426 includes an RF gasket 428 disposed therein. The plate portion 229 of the facility plate 107 includes a groove 430 in which an RF gasket 432 is disposed. The RF gasket 432 maintains RF connectivity between the substrate channel plate 404 and the facility plate 107 when the ESC substrate 402 and the substrate channel plate 404 are thermally isolated from the facility plate 107. Similarly, the ESC substrate 402 and the substrate channel plate 404 can be connected by the RF gasket 432 in the RF connection. Figure 4A and Figure 4E While the thermal interface in the embodiment shown in FIG. 4 is thermally conductive, the RF gasket 428 maintains electrical, RF connectivity between the substrate channel plate 404 and the ESC substrate 402 .

[0057] FIG. 5A to FIG. 5C is a cryogenic optical probe assembly 500 (in Figure 5D107). A schematic cross-sectional schematic diagram of an exemplary substrate support assembly 101 of one of the cryogenic optical probe assemblies 500 is shown in FIG. Each of the cryogenic optical probe assemblies 500 includes an optical fiber 510 connected to the probe controller 138. Each of the cryogenic optical probe assemblies 500 includes a mounting housing 502 disposed in the insulator plate 109 and a probe housing 504 disposed in the insulator plate 109 and the facility plate 107. The mounting housing 502 is coupled to the probe housing 504 using a probe mounting bolt 506, which is inserted through the mounting housing 502 and into a threaded hole 508 of the insulator plate 109 so that the probe assembly 500 is forced against the facility plate 107. The optical fiber 510 is connected to a cryogenic optical probe 512 disposed in the probe housing 504. The probe housing 504 includes a spring 514 to provide vertical movement for the cryogenic optical probe 512 so that a probe tip 516 of the cryogenic optical probe 512 is configured to contact the ESC 103. In one embodiment that may be combined with other embodiments described herein, the probe tip 516 contacts the ESC 103 without penetrating the surface. In another embodiment that may be combined with other embodiments described herein, Figure 5B , the probe tip 516 is disposed within the ESC 103. In the facility board 107, a threaded cap 518 surrounds the probe housing 504. An inner portion 520 of the threaded cap 518 is coupled to the probe housing 504 using an inner seal 522. The inner seal 522 allows the probe tip 516 to remain in contact with the ESC 103. In one embodiment that may be combined with other embodiments described herein, the inner seal 522 is a seal 232. In another embodiment that may be combined with other embodiments described herein, the inner seal 522 is an elastomeric seal. In yet another embodiment that may be combined with other embodiments described herein, the inner seal 522 is an O-ring or other suitable seal. An outer portion 524 of the threaded cap 518 is coupled to the facility board 107 using an outer seal 526. The outer seal 526 seals the probe housing 504 from the vacuum region 222. In one embodiment that may be combined with other embodiments described herein, the outer seal 526 is an O-ring or other suitable seal.

[0058] In summary, a substrate support assembly is provided that enables cryogenic operation of an ESC such that a substrate disposed on the ESC is maintained at a cryogenic processing temperature while maintaining other surfaces of the processing chamber at different temperatures. The substrate support assembly is disposed in a processing chamber and includes an ESC 103, an ESC base assembly 105 coupled to the ESC 103 and a facility plate 107, and an insulator plate 109 coupled to a ground plate 111. In combination with a resistive heater 128, a substrate fluid flowing through a substrate channel of the ESC base assembly 105 coupled to the ESC 103 enables the ESC base assembly 105 to be maintained at a predetermined low temperature, which helps control the lateral temperature distribution of the ESC 103 such that a substrate 124 disposed on the ESC 103 is uniformly maintained at a cryogenic processing temperature. A facility fluid flowing through a facility channel 113 of the facility plate 107 enables the facility plate 107 to be maintained at an ambient temperature, which helps maintain the insulator plate 109 and the ground plate 111 at an ambient temperature.

[0059] Additionally, semiconductor chamber components (such as substrate support assemblies, showerheads, or thermal shields) have been described that advantageously extend the life of internal conduits that carry fluid between powered and grounded portions of the semiconductor chamber components. The arc-resistant properties of the conduits beneficially extend the reliability, service life, and useful life of the semiconductor chamber components. Figure 1 As illustrated in FIG. 5 , arc-resistant conduits may be beneficially used in substrate support assemblies that flow an electrically insulating heat transfer fluid.

[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 thereof, and the scope of the disclosure is determined by the following claims.

Claims

1. A semiconductor chamber component, comprising: Power supply areas, including: a first plate having a fluid channel; Grounding area, including: Second board; an insulator plate coupling the powered area to the grounded area; and a fluid conduit disposed within the semiconductor chamber component and passing through the insulator plate and having a first end in the first plate and a second end in the second plate, wherein the fluid conduit is configured to provide a heat transfer fluid to the fluid channel, the fluid conduit comprising: An end-to-end resistance from the first end to the second end of between 0.1 MΩ and 100 MΩ. 2 . The semiconductor chamber component of claim 1 , wherein the end-to-end resistance is between 1.0 MΩ and 50 MΩ.

3. The semiconductor chamber component of claim 1, wherein the end-to-end resistance is between 1.0 MΩ and 20 MΩ.

4. The semiconductor chamber component of claim 2, wherein the fluid conduit is made of at least one material selected from the group consisting of: SiC, Ti-doped alumina, carbon-doped plastic, and metal-doped ceramic.

5. The semiconductor chamber component of claim 4, wherein the fluid conduit further comprises: An outer surface polished to a smoothness of 32 micro-inches RA or smoother near at least one end of the fluid conduit.

6. The semiconductor chamber component of claim 5, wherein the powered area and the grounded area comprise portions of a substrate support assembly, a showerhead, an electrostatic chuck, a gas distribution plate, a thermal shield, or a removable process kit.

7. The semiconductor chamber component of claim 1, wherein the fluid conduit is made of at least one material selected from the group consisting of: SiC, Ti-doped alumina, carbon-doped plastic, and metal-doped ceramic.

8. The semiconductor chamber component of claim 1, wherein the fluid conduit further comprises: An outer surface polished to a smoothness of 32 micro-inches RA or smoother near at least one end of the fluid conduit.

9. The semiconductor chamber component of claim 1, wherein the fluid conduit further comprises: An outer surface polished to a smoothness of between 4 micro-inches RA and 8 micro-inches RA near at least one end of the fluid conduit.

10. The semiconductor chamber component of claim 1, wherein the fluid conduit further comprises: A fitting is coupled to the first end of the fluid conduit, the fitting being configured for sealingly coupling to a complementary mating surface in the first plate.

11. The semiconductor chamber component of claim 1, wherein the powered area and the grounded area comprise portions of a substrate support assembly, a showerhead, an electrostatic chuck, a gas distribution plate, a thermal shield, or a removable process kit.

12. A substrate support assembly comprising: an electrostatic chuck having a support surface and a bottom surface opposite to the support surface, the electrostatic chuck having an adsorption electrode; an electrostatic chuck base assembly supporting the electrostatic chuck, the electrostatic chuck base assembly having a base channel, at least one of the electrostatic chuck and the electrostatic chuck base assembly including a powered region of the substrate support assembly, the powered region of the substrate support assembly being configured to receive RF power during a substrate processing operation; a ground plate supporting the electrostatic chuck base assembly; as well as A first fluid conduit having a first end in the electrostatic chuck base assembly and a second end in the ground plate, the first fluid conduit having an end-to-end resistance between 0.1 MΩ and 100 MΩ.

13. The substrate support assembly of claim 12, wherein the end-to-end resistance is between 1.0 MΩ and 50 MΩ.

14. The substrate support assembly of claim 12, wherein the first fluid conduit is made of at least one material selected from the group consisting of: SiC, Ti-doped alumina, carbon-doped plastic, and metal-doped ceramic.

15. The substrate support assembly of claim 12, wherein the first fluid conduit further comprises: An outer surface polished to a smoothness between 4 micro-inches RA and 8 micro-inches RA near at least one end of the first fluid conduit.

16. The substrate support assembly of claim 12, wherein the first fluid conduit further comprises: A fitting is coupled to the first end of the first fluid conduit, the fitting being configured for sealingly coupling to a complementary mating surface of the electrostatic chuck base assembly.

17. The substrate support assembly of claim 12, further comprising: a facility plate disposed between the electrostatic chuck base assembly and the ground plate, the facility plate having a facility channel configured to circulate a facility fluid; as well as A second fluid conduit is sealingly coupled to the facility channel, the second fluid conduit having an end-to-end resistance between 0.1 MΩ and 100 MΩ.

18. The substrate support assembly of claim 12, further comprising: and a second fluid conduit comprising an end-to-end resistance between 0.1 MΩ and 100 MΩ, wherein the first fluid conduit and the second fluid conduit are coupled to a base channel disposed in the electrostatic chuck base assembly, the base channel being configured to flow a refrigerant therethrough.

19. A substrate support assembly comprising: an electrostatic chuck having a support surface and a bottom surface opposite to the support surface, the electrostatic chuck having an adsorption electrode and a heater; an electrostatic chuck base assembly supporting the electrostatic chuck, the electrostatic chuck base assembly having a base channel, the electrostatic chuck base assembly being configured to be RF powered during a substrate processing operation; a ground plate supporting the electrostatic chuck base assembly; a first fluid conduit extending from the ground plate to the base channel, the first fluid conduit providing an inlet for flowing a heat transfer fluid into the base channel; as well as a second fluid conduit extending from the ground plate to the base channel, the second fluid conduit providing an outlet for a heat transfer fluid to flow out of the base channel, the first fluid conduit and the second fluid conduit being made of at least one material selected from the group consisting of SiC, Ti-doped alumina, carbon-doped plastic, and metal-doped ceramic, and the first fluid conduit and the second fluid conduit each having an end-to-end resistance between 0.1 MΩ and 100 MΩ.

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