Electrostatic chuck designs with temperature compensating ceramic structures

Abstract

A substrate support includes a baseplate made of a metallic material and a ceramic plate disposed on the baseplate to support a substrate. The ceramic plate includes a first dielectric material having a first temperature coefficient of resistance, one or more clamping electrodes disposed in the first dielectric material to clamp the substrate, and a layer having a second temperature coefficient of resistance disposed in the first dielectric material between the one or more clamping electrodes and a substrate-facing surface of the ceramic plate.

Description

Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAELECTROSTATIC CHUCK DESIGNS WITH TEMPERATURE COMPENSATING CERAMIC STRUCTURESCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No.63 / 746,458, filed on January 17, 2025. The entire disclosure of the above application is incorporated herein by reference.FIELD

[0002] The present disclosure relates generally to substrate processing systems and more particularly to electrostatic chuck designs with temperature compensating ceramic structures.BACKGROUND

[0003] The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.

[0004] A substrate processing system (also called a tool) typically includes a plurality of processing chambers (also called stations or process modules) to perform deposition, etching, and other treatments of substrates such as semiconductor wafers. Examples of deposition processes that may be performed on a substrate include, but are not limited to, plasma enhanced chemical vapor deposition (PECVD), chemically enhanced plasma vapor deposition (CEPVD), atomic layer deposition (ALD), and plasma enhanced ALD (PEALD). Examples of etching processes that may be performed on a substrate include, but are not limited to, chemical etching, plasma etching, and reactive ion etching processes. Additional examples of the processes that can be performed in processing chambers include cleaning processes used to periodically clean the processing chambers.

[0005] During processing, a substrate is arranged on a substrate support assembly such as a pedestal or an electrostatic chuck (ESC) arranged in a processing chamber of the substrate processing system. A computer-controlled robot typically transfers substratesAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAfrom one processing chamber to another in a sequence in which the substrates are to be processed. During deposition, gas mixtures including one or more precursors are introduced into the processing chamber, and plasma is struck to activate chemical reactions. During etching, gas mixtures including etch gases are introduced into the processing chamber, and plasma is struck to activate chemical reactions. The processing chambers are periodically cleaned by supplying a cleaning gas into the processing chamber and striking plasma.SUMMARY

[0006] A substrate support comprises a baseplate made of a metallic material and a ceramic plate disposed on the baseplate to support a substrate. The ceramic plate comprises a first dielectric material having a first temperature coefficient of resistance, one or more clamping electrodes disposed in the first dielectric material to clamp the substrate, and a layer having a second temperature coefficient of resistance disposed in the first dielectric material between the one or more clamping electrodes and a substratefacing surface of the ceramic plate.

[0007] In additional features, the layer comprises a second dielectric material that is different than the first dielectric material.

[0008] In additional features, the layer comprises a cavity filled with air.

[0009] In additional features, the layer comprises a cavity. The substrate support further comprises a conduit connected to the layer to supply a gas to the cavity in the layer.

[0010] In additional features, the substrate support further comprises a gas supply connected to the conduit to supply the gas at a selected pressure.

[0011] In additional features, the first temperature coefficient of resistance of the first dielectric material is negative. The second temperature of coefficient of the layer is less negative than the first temperature coefficient of resistance.

[0012] In additional features, the layer comprises a second dielectric material and wherein the layer is porous.

[0013] In additional features, the first temperature coefficient of resistance of the first dielectric material is negative. The second temperature of coefficient of the layer is positive.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA

[0014] In additional features, the layer is coated on the one or more clamping electrodes.

[0015] In additional features, the layer is disposed on the one or more clamping electrodes.

[0016] In additional features, the layer is disposed in the first dielectric material at a predetermined distance from the one or more clamping electrodes.

[0017] In additional features, the layer is disposed in the first dielectric material at a predetermined distance from the substrate-facing surface of the ceramic plate.

[0018] In additional features, the layer has a predetermined thickness.

[0019] In additional features, an area of the layer is greater than or equal to an area of the one or more clamping electrodes.

[0020] In additional features, the substrate support further comprises one or more heaters disposed in the ceramic plate, and one or more cooling channels disposed in the baseplate.

[0021] In still other features, a substrate support comprises a first layer of a first dielectric material having a first temperature coefficient of resistance, one or more clamping electrodes disposed in the first layer, and a second layer having a second temperature coefficient of resistance disposed in the first layer above the one or more clamping electrodes.

[0022] In additional features, the second layer comprises a second dielectric material that is different than the first dielectric material.

[0023] In additional features, the second layer comprises a cavity filled with air.

[0024] In additional features, the second layer comprises a cavity, the substrate support further comprising a conduit connected to the second layer to supply a gas to the cavity in the layer.

[0025] In additional features, the substrate support further comprises a gas supply connected to the conduit to supply the gas at a selected pressure.

[0026] In additional features, the first temperature coefficient of resistance of the first layer is negative. The second temperature of coefficient of the second layer is less negative than the first temperature coefficient of resistance.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA

[0027] In additional features, the second layer comprises a second dielectric material and wherein the second layer is porous.

[0028] In additional features, the first temperature coefficient of resistance of the first layer is negative. The second temperature of coefficient of the second layer is positive.

[0029] In additional features, the second layer is coated on the one or more clamping electrodes.

[0030] In additional features, the second layer is disposed on the one or more clamping electrodes.

[0031] In additional features, the second layer is disposed in the first layer at a predetermined distance from the one or more clamping electrodes.

[0032] In additional features, the second layer is disposed in the first layer at a predetermined distance above the one or more clamping electrodes.

[0033] In additional features, the second layer has a predetermined thickness.

[0034] In additional features, an area of the second layer is greater than or equal to an area of the one or more clamping electrodes.

[0035] Further areas of applicability of the present disclosure will become apparent from the detailed description, the claims and the drawings. The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

[0037] FIG. 1 shows an example of a substrate processing system comprising a substrate support that utilizes a ceramic plate according to the present disclosure;

[0038] FIG. 2 shows another example of a substrate processing system comprising a substrate support that utilizes a ceramic plate according to the present disclosure;

[0039] FIGS. 3-5 illustrate a de-chucking problem in electrostatic chucks (ESCs);

[0040] FIG. 6 shows a first design of a ceramic plate for an ESC of FIGS. 1 and 2 according to the present disclosure;Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA

[0041] FIG. 7 shows a second design of a ceramic plate for an ESC of FIGS. 1 and 2 according to the present disclosure;

[0042] FIG. 8 shows a third design of a ceramic plate for an ESC of FIGS. 1 and 2 according to the present disclosure;

[0043] FIG. 9 shows a graph of resistance versus temperature for a ceramic plate comprising a single dielectric material;

[0044] FIG. 10 shows a graph of resistance versus temperature a first material of the ceramic plate of FIG. 8 having a negative temperature coefficient (TCR) slope and a second material of a ceramic plate having a positive TCR slope; and

[0045] FIG. 11 shows a graph of resistance versus temperature for the ceramic plate of FIG. 8 comprising the first material and the second material having the TCR slopes shown in FIG. 10.

[0046] In the drawings, reference numbers may be reused to identify similar and / or identical elements.DETAILED DESCRIPTION

[0047] An electrostatic chuck (ESC) comprises a ceramic plate in which one or more clamping electrodes are embedded. The ceramic plate is made of a ceramic (dielectric) material (e.g., AI2O3 or alumina). The ceramic plate is disposed on a baseplate made of a metallic material (e.g., aluminum or an alloy of aluminum). A substrate is arranged on a top surface of the ceramic plate for processing.

[0048] Before processing begins, the substrate is clamped to the top surface of the ceramic plate by applying high voltage (e.g., DC voltage or HV waveform) to the clamping electrodes. When voltage is applied, the clamping electrodes electrostatically attract the substrate and clamp the substrate to the top surface of the ceramic plate. During processing, the clamping electrodes keep the substrate clamped to the ceramic plate. After the processing is completed, de-chucking (de-clamping) is performed to de-chuck (de-clamp) the substrate from the top surface of the ceramic plate. During de-chucking, depending on the type of clamping electrodes (e.g., monopolar, bipolar, etc.), either the voltage to the clamping electrodes is turned off, or polarity of the voltage applied across the clamping electrodes is reversed to remove the electrostatic attraction. After de-chucking, a transfer robot transports the substrate out of the processing chamber.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA

[0049] De-chucking can be challenging and difficult when processes performed on substrates involve high temperatures, long durations, high voltage, or a combination of these parameters. The ceramic plate of the ESC is typically made of a ceramic material (e.g., alumina (AI2O3)). Alumina has a negative temperature coefficient of resistance (TCR), which results in a decrease in resistance of the ceramic plate as the temperature of the ceramic plate increases. Eventually, the resistance of the ceramic material decreases to a low value at which the ceramic material becomes conductive. The low resistance of the ceramic material at high process temperatures causes electrical charges from the clamping electrodes to slowly migrate to and accumulate on the top surface of the ceramic plate during the clamping process. Consequently, during dechucking, residual charges may be present on the top surface of the ceramic plate. Discharging these charges to de-clamp the substrate can be challenging and difficult.

[0050] Various methods have been employed to tackle the de-chucking problem. For example, ESCs can use a Johnsen-Rahbeck (JR) ceramic, which comprises a semiconductor material instead of a dielectric material. Other methods include reversing polarity of voltage applied to the clamping electrodes, or using a pure ceramic material (i.e., ceramic of high purity and with least impurities). However, these approaches have limitations. These approaches often depend on specific process conditions, require optimization, and are typically limited to a narrow range of temperatures. Consequently, these approaches do not fully address the de-chucking issue.

[0051] For example, ESCs with JR ceramic utilize ceramics that operate in conductive region during processes. However, JR ceramic is only suitable for a small temperature range, and resistance variation along a large temperature range can still lead to de-chucking issues. Further, with JR ceramic, the clamping process relies on the surface roughness of the ceramic, which makes it challenging to ensure consistent performance across different chambers. Moreover, this approach can be affected by manufacturing variability and may experience drift over time.

[0052] Another de-chucking method is the reverse voltage polarity (RVP) method, which also has challenges. Optimization is required for each recipe, which can introduce complexity and increase process time, resulting in reduced throughput. Another approach is AC clamping, which can be expensive and may cause temperature ripples on the substrate surface as the clamping force changes.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA

[0053] Several problems can arise due to de-chucking issues. For example, a dechucking problem can cause a false alarm indicating failure of dynamic alignment (DA) sensors used in ESCs to align substrates when in fact the DA sensors, which detect substrate placement and removal, may be operating normally. Also, to overcome the dechucking problem, more mechanical force may be used to disengage the substrate from the ESC, which can damage the substrate.

[0054] To fully address the de-chucking issue and solve the above problems, the present disclosure provides various designs of a ceramic structure that incorporate temperature-independent properties. The designs ensure that chucking / de-chucking are temperature independent and do not have the above problems. The designs compensate the negative TCR-based behavior of the ceramic plate comprising alumina by introducing materials with a much lower TCR slope than alumina into the ceramic plate to dominate the overall resistance change behavior. Alternatively, the negative TCR-based behavior can be compensated by incorporating a material with a positive TCR into the ceramic plate, which can maintain a constant or low resistance variation as the temperature changes.

[0055] Specifically, the present disclosure provides two methods that can fully address the de-chucking issue: 1 ) Dominant resistance approach, and 2) Reverse TCR approach. The dominant resistance approach can be implemented in two ways: by adding an insulating layer above the clamping electrodes in the ceramic plate; or by adding a dielectric layer of another material to the ceramic plate, which can be porous or solid, and which has much lower TCR slope than alumina.

[0056] In a first implementation of the dominant resistance design, a layer with dominant resistance and a low TCR slope than alumina is added to the ceramic plate. Specifically, the low TCR layer is disposed above the clamping electrodes in the ceramic plate comprising alumina so that the resistances of the ceramic material (alumina) and the low TCR layer are in series. As the temperature increases, while the resistance of ceramic material (alumina) decreases, the resistance of the added low TCR layer is more stable due to its low TCR slope and becomes the dominant resistance. This results in a smaller overall slope of the TCR for the ceramic plate than when the ceramic plate is solely made of alumina. The added low TCR layer acts as an insulator layer that can block charges from migrating to the surfaces of the ceramic.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA

[0057] One way to implement the layer with dominant resistance is by adding a gap in the ceramic plate above the clamping electrodes and filling the gap with air or an inert gas (e.g., He / Ar) at a specific pressure. The gap filled with air or inert gas can be called a gas layer. The gas layer has a much smaller TOR than alumina and provides the dominant resistance function. While He is preferred due to its high thermal conductivity, N2 or SF6 are alternatives that are less costly and that have a higher breakdown voltage than He. The gap dimension can be designed such that the gap is away from the ionization region. The gas pressure can be designed such that the gas will not break down at the clamping voltage and the process temperature used.

[0058] The first implementation provides other advantages in addition to solving the dechucking issue. For example, the gas layer may also create a thermal choke point, which can be beneficial in high-temperature processes. For example, since the gas layer may also create a thermal choke point, less power may be supplied to heaters that are embedded in the ceramic plate to heat the substrate. Also, the gas pressure can be changed, which can be used as a tuning factor for the capacitance between clamping electrode and the substrate. For example, depending on process temperature, the gas pressure can be adjusted such that less power may be applied to the clamping electrodes to clamp the substrate.

[0059] In a second implantation of the dominant resistance design, a dielectric layer of another material, which can be porous or solid, and which has much lower TCR slope than alumina can be added into the ceramic plate above the clamping electrodes. As in the first implementation, as the temperature increases, while the resistance of ceramic material (alumina) decreases, the resistance of the added low TCR layer is more stable due to its low TCR slope and becomes the dominant resistance. This results in a smaller overall slope of the TCR for the ceramic plate than when the ceramic plate is solely made of alumina. The added low TCR layer acts as an insulator layer that can block charges from migrating to the surfaces of the ceramic. If porous material is used, the porosity of the material needs to be uniform to ensure no impact on the clamping process. Unlike the gas-filled gap layer, this design is fixed (i.e., not changeable once implemented) since the porosity of the material is fixed and cannot be changed like the gas pressure in the gap layer. Accordingly, the tuning parameter provided by the gas-filled gap layer is unavailable in this design.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA

[0060] In the reverse TCR approach, a temperature compensating layer is deposited (or coated) on the clamping electrodes or is added to the ceramic plate above the clamping electrodes to compensate for resistance changes in the ceramic material. The material of the compensating layer has a positive TCR, which compensates for the negative TCR of the ceramic material (alumina). The material of the temperature compensating layer can be selected such that the overall TCR of the ceramic plate is relatively flat over the temperature range of the process. These and other features of the present disclosure are described below in detail.

[0061] The present disclosure is organized as follows. Initially, examples of substrate processing systems comprising a substrate support that utilizes a ceramic plate according to the present disclosure are shown and described with reference to FIGS. 1 and 2. A de-chucking problem that occurs in electrostatic chucks (ESCs) is shown and described with reference to FIGS. 3-5 and 9. Different designs of a ceramic plate for an ESC according to the present disclosure that can be used in the ESCs shown in FIGS. 1 and 2 are shown and described with reference to FIGS. 6-8. The designs of the present disclosure are described with reference to graphs of resistance versus temperature of materials used in the ceramic plate shown in FIGS. 10 and 11.EXAMPLES OF SUBSTRATE PROCESSING SYSTEM

[0062] FIG. 1 shows an example of a substrate processing system 10 comprising a processing chamber 28. The processing chamber 28 uses an inductively coupled plasma (ICP) to etch substrates. The processing chamber 28 comprises a dielectric window 24 arranged along a top end of the processing chamber 28. An inductive coil 16 is arranged on the dielectric window 24. While a single coil is shown, the substrate processing system 10 may comprise a plurality of coils (e.g., inner and outer coils). The inductive coil 16 is energized to generate a plasma 41 in the processing chamber 28 during substrate processing as follows.

[0063] A coil driving circuit 11 is connected to the inductive coil 16. The coil driving circuit 11 comprises a radio frequency (RF) source 12, a pulsing circuit 14, and a tuning circuit (i.e., matching circuit) 13. The RF source 12 generates an RF signal. The pulsing circuit 14 controls a transformer coupled plasma (TCP) envelope of the RF signal and varies a duty cycle of TCP envelope (e.g., between 1% and 99%) during operation. The pulsing circuit 14 and the RF source 12 can be combined or separate. The tuning circuit 13 may be directly connected to the inductive coil 16. The tuning circuit 13 tunes an output of theAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POARF source 12 to a desired frequency and / or a desired phase, and matches an impedance of the inductive coil 16.

[0064] A gas delivery system 56 comprises gas sources 57 to supply various gases to the processing chamber 28. The gas sources 57 supply process gases used to generate the plasma 41 for substrate processing. The gas sources 57 also supply inert gases and purge gases during substrate processing. The gas delivery system 56 comprises a gas metering system 58 including valves and mass flow controllers (MFCs) to supply the various gases from the gas sources 57 to the processing chamber 28. The gas delivery system 56 comprises a manifold 59 through which the various gases are supplied to the processing chamber 28. A gas injector 63 may be arranged at a center of the dielectric window 24 to inject gases from the manifold 59 into the processing chamber 28. Additionally or alternatively, the gases may be injected from the side of the processing chamber 28.

[0065] The processing chamber 28 comprises a substrate support (or pedestal) 30 to support a substrate 34. During substrate processing, a process gas is supplied to the processing chamber 28 through the gas injector 63. The plasma 41 is generated inside of the processing chamber 28 by supplying RF power from the coil driving circuit 11 to the inductive coil 16. The RF power ignites the process gas to generate the plasma 41. The plasma 41 etches an exposed surface of the substrate 34. An RF source 50, a pulsing circuit 51, and a bias matching circuit 52 may be used to bias the substrate support 30 during processing to control ion energy.

[0066] The substrate support 30 comprises an electrostatic chuck (ESC) that electrostatically clamps the substrate 34 to the substrate support 30. The substrate support 30 comprises a baseplate 32 and a ceramic plate 33. The baseplate 32 is made of a metallic material (e.g., aluminum or an aluminum alloy). The ceramic plate 33 is arranged on the baseplate 32. A thermal resistance layer 36 made of an electrically and thermally insulating material is disposed between the ceramic plate 33 and the baseplate 32. The substrate 34 is arranged on the ceramic plate 33 during processing.

[0067] The ceramic plate 33 is described below in further detail with reference to FIG. 6 onwards. Briefly, the ceramic plate 33 is primarily made of a ceramic material such as alumina (AI2O3) and further comprises one of the temperature compensating structures shown and described below with reference to FIGS. 6-8. The ceramic plate 33 comprises a heater 35 to heat the substrate 34 during processing. The ceramic plate 33 comprisesAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAa clamping electrode 37 to clamp the substrate 34 to the ceramic plate 33 during processing. The clamping electrode 37 is coupled to a power supply 43. A system controller 64 controls the power supply 43 to control the voltage supplied to the clamping electrode 37.

[0068] The baseplate 32 comprises one or more cooling channels 38 to cool the substrate support 30. A coolant supply system 39 (also called a chiller) supplies a coolant to the cooling channels 38 to regulate the temperature of the substrate support 30. The substrate support 30 includes a temperature sensor 31 to sense the temperature of substrate support 30. The system controller 64 controls the power supplied to the heater 35 based on feedback from the temperature sensor 31. The system controller 64 controls the coolant supply system 39 to control flow of the coolant through the cooling channels 38 based on feedback from the temperature sensor 31.

[0069] An exhaust system 65 includes a valve 66 and pump 67 to control pressure in the processing chamber 28 and / or to remove reactants from the processing chamber 28 by purging or evacuation. The system controller 64 controls the etching process by controlling the components of the substrate processing system 10. For example, the controller 64 monitors system parameters; controls delivery of the gases from the gas delivery system 56; controls striking, maintaining, and extinguishing of the plasma 41 ; controls the exhaust system 65 for removal of reactants from the processing chamber 28; and so on. Additionally, the system controller 64 controls the coil driving circuit 11, the RF source 50, the pulsing circuit 51 , and the bias matching circuit 52, and so on.

[0070] FIG. 2 shows another example of a substrate processing system 100 including a processing chamber 102 that uses a capacitively coupled plasma (CCP) to process substrates. The processing chamber 102 comprises a substrate support (also called a pedestal) 104 and a showerhead 106. For example, the pedestal 104 includes an electrostatic chuck (ESC) 104 to support a substrate 120 during processing. The showerhead 106 is connected to a top plate of the processing chamber 102. The ESC 104 comprises a baseplate 108 and a ceramic plate 110 disposed on the baseplate 108. For example, the baseplate 108 is made of a metallic material (e.g., aluminum or an aluminum alloy).

[0071] The ceramic plate 110 is described below in further detail with reference to FIG.6 onwards. Briefly, the ceramic plate 110 is primarily made of a ceramic material such as alumina (AI2O3) and further comprises one of the temperature compensating structuresAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAshown and described below with reference to FIGS. 6-8. The ceramic plate 110 comprises a clamping electrode 112 embedded in the ceramic plate 110 to clamp the substrate 120 to the ESC 104 during processing. The clamping electrode 112 is coupled to a power supply 113. A system controller 150 controls the power supply 113 to control the voltage supplied to the clamping electrode 112. The ceramic plate 110 comprises a heater 114 to heat the substrate 120.

[0072] The baseplate 108 comprises one or more cooling channels 116 to cool the ESC 104. A coolant supply system 118 supplies a coolant to the cooling channels 116 to regulate the temperature of the ESC 104. The ESC 104 comprises a temperature sensor 124 to sense the temperature of the ESC 104. The system controller 150 controls the heater 114 and the flow of the coolant through the cooling channels 116 based on the feedback received from the temperature sensor 124.

[0073] The showerhead 106 supplies one or more gases, gas mixtures, and vaporized precursors into the processing chamber 102. For example, the gases comprise process gases, gas mixtures, vaporized precursors, inert gases, purge gases, and so on. While not shown, the showerhead 106 may also comprise a heater and one or more cooling channels that receive the coolant from the coolant supply system 118 to regulate the temperature of the showerhead 106. The showerhead 106 comprises a temperature sensor 122. The system controller 150 controls the heater and the flow of the coolant through the cooling channels in the showerhead 106 based on the feedback received from the temperature sensor 122 to regulate the temperature of the showerhead 106.

[0074] The substrate processing system 100 comprises a gas delivery system 130, a vapor delivery system 132, and a manifold 134. The gas delivery system 130 comprises a plurality of gas sources, valves, and mass flow controllers (MFCs) (all not shown) to supply various gases and gas mixtures at various flow rates. The gas delivery system 130 supplies the various gases and gas mixtures to the manifold 134. For example, the various gases comprise process gases, purge gases, inert gases, and so on. The vapor delivery system 132 supplies one or more vaporized precursors to the manifold 134. The manifold 134 is connected to the gas delivery system 130, the vapor delivery system 132, and the showerhead 106. The showerhead 106 receives one or more gases, gas mixtures, and vaporized precursors from the manifold 134 and supplies them into the processing chamber 102.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA

[0075] The substrate processing system 100 comprises a radio frequency (RF) power supply 136. For example, the RF power supply 136 supplies RF power to the showerhead 106. When one or more gases are supplied through the showerhead 106 into the processing chamber 102, the RF power supplied by the RF power supply 136 to the showerhead 106 strikes a plasma 141 between the showerhead 106 and the ESC 104 during substrate processing.

[0076] The substrate processing system 100 comprises a valve 144 and a pump 146. The pump 146 is connected to the processing chamber 102 through the valve 144. The pump 146 is connected to an exhaust system (not shown) of the substrate processing system 100. The pump 146 maintains pressure (e.g., vacuum) in the processing chamber 102. The pump 146 also evacuates residual gases and reactants from the processing chamber 102 into the exhaust system. The system controller 150 controls the components of the substrate processing system 100 described above. For example, the system controller 150 controls the gas delivery system 130, the vapor delivery system 132, the RF power supply 136, the valve 144 and the pump 146, and so on.DE-CHUCKING ISSUE

[0077] FIGS. 3-5 illustrate the de-chucking problem that typically occurs in ESCs at elevated temperatures, which are resolved by the various ESC ceramic plate designs of the present disclosure shown in FIGS. 6-8. FIG. 3 shows clamping at room temperature. FIG. 4 shows clamping at elevated temperatures (temperatures greater than room temperature). FIG. 5 shows de-chucking at elevated temperatures.

[0078] FIGS. 3-5 show a typical ESC 200 comprising a ceramic plate 202 disposed on a metallic baseplate, which is omitted but is similar to the baseplates 32 and 108 shown in FIGS. 1 and 2, respectively. In the ESC 200 shown in FIGS. 3-5, the heater is also omitted but is presumed to be present in the ESC 200, and only the clamping electrodes are shown to focus on the de-chucking issue. The ESC 200 can be used in the substrate processing systems 10 and 100 shown in FIGS. 1 and 2, respectively. The ESC 200 has de-chucking issues at elevated temperatures as described below.

[0079] The ESC 200 comprises the ceramic plate 202 in which one or more clamping electrodes 204-1 , 204-2 (collectively called the clamping electrodes 204) are embedded. For example, the clamping electrodes 204 can comprise monopolar or bipolar electrodes. The ceramic plate 202 is made of a ceramic (dielectric) material (e.g., AI2O3 or alumina) 208. The ceramic plate 202 is disposed on a baseplate (not shown) made of a metallicAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAmaterial (e.g., aluminum or an alloy of aluminum). A substrate 206 is arranged on a top surface of the ceramic plate 202 for processing.

[0080] In FIG. 3, before processing begins, the substrate 206 is clamped to the top surface of the ceramic plate 202 by applying high voltage (e.g., DC voltage or other HV waveforms) from a power supply (e.g., 43 or 113 shown in FIGS. 1 and 2) to the clamping electrodes 204. When voltage is applied, the clamping electrodes 204 electrostatically attract the substrate 206 and clamp the substrate 206 to the top surface of the ceramic plate 202 as shown. During processing, the clamping electrodes 204 keep the substrate 206 clamped to the ceramic plate 202.

[0081] After the processing is completed, de-chucking (de-clamping) is performed to dechuck (de-clamp) the substrate 206 from the top surface of the ceramic plate 202. During de-chucking, depending on the type of the clamping electrodes (e.g., monopolar, bipolar, etc.), either the voltage to the clamping electrodes 204 is turned off, or polarity of the voltage applied across the clamping electrodes 204 is reversed. After de-chucking, a transfer robot transports the substrate 206 out of the processing chamber.

[0082] In FIG. 4, de-chucking can be challenging and difficult when processes are performed at high temperatures, for long durations, at high voltage or using combination of these parameters. The ceramic plate 202 of the ESC 200 is typically made of the ceramic material 208 (e.g., alumina), which has a negative temperature coefficient of resistance (TCR). Due to the negative TCR, the resistance of the ceramic material 208 in the ceramic plate 202 decreases as the temperature of the ceramic plate 202 increases during substrate processing as shown in FIG. 9.

[0083] Some processes used to process the substrate 206 are performed at high temperatures (e.g., several hundred degrees), are formed for a long duration, or both. Eventually, after being subjected to sustained high temperatures during substrate processing, the resistance of the ceramic material 208 in the ceramic plate 202 decreases to a low value at which the ceramic material 208 becomes conductive as shown in FIG. 9. The low resistance of the ceramic material 208 at high process temperatures causes electrical charges to slowly migrate from the clamping electrodes 204 and accumulate on the top surface of the ceramic plate 202 during the clamping process as shown at 210, 212, 214, 216.

[0084] In FIG. 5, during de-chucking, residual charges may be present on the top surface of the ceramic plate as shown 210, 212, 214, 216. Consequently, even afterAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POApower supply to the clamping electrodes 204 is stopped, discharging these charges to de-clamp the substrate 206 can be challenging and difficult. As already described above, various methods have been employed to tackle the de-chucking problem but these approaches have limitations and do not fully address the de-chucking issue.ESC CERAMIC PLATE DESIGNS

[0085] FIGS. 6-8 show various ceramic plate designs according to the present disclosure that resolve the de-chucking issue with ESCs described above. FIG. 6 shows the dominant resistance approach implemented by adding an insulating layer to the ceramic plate above the clamping electrodes. FIG. 7 shows the dominant resistance approach implemented by adding a dielectric layer of another material to the ceramic plate, where the other material can be porous or solid and has a lower TCR slope than the primary ceramic material of the ceramic plate. FIG. 8 shows the reverse TCR approach in which a temperature compensating layer is deposited (or coated) on the clamping electrodes or is added to the ceramic plate above the clamping electrodes to compensate for resistance changes in the primary ceramic material of the ceramic plate during substrate processing at high temperatures.

[0086] The designs of the ceramic plate shown in FIGS. 6-8 ensure that chucking / de-chucking are temperature independent and do not have the de-chucking problems described above. The designs compensate the negative TCR-based behavior of the ceramic plate comprising a primary ceramic material by introducing materials with a lower TCR slope than the primary ceramic material into the ceramic plate to dominate the overall resistance change behavior of the ceramic plate. Alternatively, the negative TCR-based behavior can be compensated by incorporating a material with a positive TCR into the ceramic plate, which can maintain a constant or low resistance variation as the temperature of the ceramic plate changes. Accordingly, the designs shown in FIGS. 6-8 can be used in processes requiring high temperatures and long durations without causing de-chucking issues. The ceramic plates 32 and 108 shown in FIGS. 1 and 2 can comprise any of the designs shown in FIGS. 6-8.FIRST DESIGN

[0087] FIG. 6 shows a first design of the ceramic plate using the dominant resistance approach according to the present disclosure. In the first design, an ESC 300 comprises a ceramic plate 302 disposed on a metallic baseplate, which is omitted but is similar to the baseplates 32 and 108 shown in FIGS. 1 and 2, respectively. In the ESC 300 shownAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAin FIG. 6, the heater is also omitted but is presumed to be present in the ESC 300, and only the clamping electrodes are shown to focus on how the first design of the ceramic plate solves the de-chucking problem. The ESC 300 can be used in the substrate processing systems 10 and 100 shown in FIGS. 1 and 2, respectively. The ESC 300 does not have the de-chucking problem at elevated temperatures.

[0088] The ESC 300 comprises the ceramic plate 302 in which one or more clamping electrodes 304-1 , 304-2 (collectively called the clamping electrodes 304) are embedded. For example, the clamping electrodes 304 can comprise monopolar or bipolar electrodes. The ceramic plate 302 comprises a first ceramic (dielectric) material (e.g., AI2O3 or alumina) 310. The clamping electrodes 304 are embedded in the first material 310 in the ceramic plate 302. The ceramic plate 302 is disposed on a baseplate (not shown) made of a metallic material (e.g., aluminum or an alloy of aluminum). A substrate 306 is arranged on a top surface of the ceramic plate 302 for processing.

[0089] The first material 310 in the ceramic plate 302 (e.g., alumina) has a negative temperature coefficient of resistance (TOR). Due to the negative TOR, the resistance of the first material 310 in the ceramic plate 302 decreases as the temperature of the ceramic plate 302 increases during substrate processing as shown in FIG. 9.

[0090] Additionally, the ceramic plate 302 comprises an insulating layer 320. The insulating layer 320 is disposed in the first material 310 of the ceramic plate 302. The insulating layer 320 is disposed above the clamping electrodes 304 in the first material 310 of the ceramic plate 302. The insulating layer 320 is disposed in the ceramic plate 302 between the clamping electrodes 304 and a top surface of the ceramic plate 302 on which the substrate 306 lies.

[0091] The insulating layer 320 is disposed at a predetermined distance above the clamping electrodes 304. The distance at which the insulating layer 320 is disposed above the clamping electrodes 304 is a design parameter. The insulating layer 320 is disposed at a predetermined distance below the top surface of the ceramic plate 302. The distance at which the insulating layer 320 is disposed below the top surface of the ceramic plate 302 is a design parameter. The insulating layer 320 has a predetermined thickness (height) measured along a vertical axis of the ESC 300. The thickness (height) of the insulating layer 320 is a design parameter.

[0092] The distances of the insulating layer 320 above the clamping electrodes 304 and below the top surface of the ceramic plate 302 and the thickness (height) of the insulatingAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAlayer 320 are selected such that the insulating layer 320 is away from the ionization region above the substrate 306. An area (e.g., diameter) of the insulating layer 320 is greater than or equal to an area (e.g., diameter) of the clamping electrodes 304. In some examples, the area of the insulating layer 320 can be slightly less than the area of the clamping electrodes 304. The area of the insulating layer 320 is also a design parameter.

[0093] The resistances of the first material 310 shown at 312, 314 and the resistance of the insulating layer 320 shown at 322 are in series. As the temperature of the ceramic plate 302 increases during substrate processing, the resistance of the first material 310 decreases due to the negative TCR of the first material 310. However, the insulating layer 320 has a lower TCR slope than the first material 310 of the ceramic plate 302. Consequently, the insulating layer 320 exhibits a more dominant resistance than the first material 310 of the ceramic plate 302.

[0094] Specifically, due to the low TCR, the resistance of the insulating layer 320 is more stable regardless of the variation (e.g., increase) in the temperature of the ceramic plate 302 and becomes the dominant resistance. This results in a smaller overall TCR slope for the ceramic plate 302 comprising the combination of the first material 310 and the insulating layer 320 than when the ceramic plate is solely made of the first material 310 (e.g., the ceramic plate 302 shown in FIGS. 3-5). The insulating layer 320 acts as an insulator layer that can block charges from migrating to the top surface of the ceramic plate 302, which solves the de-chucking problem associate with the ceramic plate 302 shown in FIGS. 3-5.

[0095] One way to implement the insulating layer 320 is by adding a gap (e.g., by forming a cavity) in the ceramic plate 302 above the clamping electrodes 304. In one example, the cavity (i.e. , the insulating layer 320) may be formed during the manufacture of the ESC 300 during which the cavity (i.e., the insulating layer 320) may be filled with air.

[0096] In another example, a conduit 330 may be connected to the cavity in the insulating layer 320 through the baseplate and the ceramic plate 302 as shown. In use, the cavity in the insulating layer 320 can be filled with an inert gas (e.g., He / Ar) at a specific pressure. For example, conduit 330 may be coupled to the gas delivery system 56, 130 shown in FIGS. 1 and 2, which can supply the gas to the insulating layer 320 through the conduit 330. The insulating layer 320 filled with air or inert gas can be called a gas layer. While helium (He) is preferred due to its high thermal conductivity, N2 or SF6Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAare alternatives that are less costly and that have a higher breakdown voltage than He. Whether filled with air or a specific gas, the insulating layer 320 has a smaller TCR slope than the primary ceramic material (the first material) 310 of the ceramic plate 302 and provides the dominant resistance function.

[0097] When filled with a gas, the pressure of the gas in the insulating layer 320 can be selected such that the gas does not break down at the clamping voltage applied to the clamping electrodes 304 and at the process temperatures used to process the substrate 306. The pressure of the gas in the insulating layer 320 can be controlled by the gas delivery system 56, 130 and the system controller 64, 150 shown in FIGS. 1 and 2.

[0098] Thus, since the pressure of the gas in the insulating layer 320 can be controlled, the insulating layer 320 provides a control knob for controlling the overall TCR of the ceramic plate 302. Accordingly, depending on the temperature of the process used to process the substrate 306, the TCR of the ceramic plate 302 can be controlled by controlling the pressure of the gas in the insulating layer 320. The clamping voltage applied to the clamping electrodes 304 can also be adjusted based on the TCR of the ceramic plate 302.

[0099] The first design provides other advantages in addition to solving the de-chucking problem. For example, the insulating layer 320 may also create a thermal choke point, which can be beneficial in high-temperature processes used to process the substrate 306. For example, since the insulating layer 320 may also create a thermal choke point, less power may be supplied to heaters that are embedded in the ceramic plate 302 to heat the substrate 306.

[0100] Also, since the gas pressure in the insulating layer 320 can be changed, the gas pressure can be used as a tuning factor for the capacitance between clamping electrodes 304 and the substrate 306. For example, depending on the temperature of the process used to process the substrate 306, the gas pressure in the insulating layer 320 can be adjusted such that less power may be applied to the clamping electrodes 304 to clamp the substrate 306.SECOND DESIGN

[0101] FIG. 7 shows a second design of the ceramic plate using the dominant resistance approach according to the present disclosure. FIG. 7 shows a second way of implanting the insulating layer in the ceramic plate. In the second design, an ESC 400 comprises aAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAceramic plate 402 disposed on a metallic baseplate, which is omitted but is similar to the baseplates 32 and 108 shown in FIGS. 1 and 2, respectively. In the ESC 400 shown in FIG. 7, the heater is also omitted but is presumed to be present in the ESC 400, and only the clamping electrodes are shown to focus on how the second design of the ceramic plate solves the de-chucking problem. The ESC 400 can be used in the substrate processing systems 10 and 100 shown in FIGS. 1 and 2, respectively. The ESC 400 does not have the de-chucking problem at elevated temperatures.

[0102] The ESC 400 comprises the ceramic plate 402 in which one or more clamping electrodes 304-1 , 304-2 (collectively called the clamping electrodes 304) are embedded. For example, the clamping electrodes 304 can comprise monopolar or bipolar electrodes. The ceramic plate 402 comprises the first ceramic (dielectric) material (e.g., alumina) 310. The clamping electrodes 304 are embedded in the first material 310 in the ceramic plate 402. The ceramic plate 402 is disposed on a baseplate (not shown) made of a metallic material (e.g., aluminum or an alloy of aluminum). A substrate 406 is arranged on a top surface of the ceramic plate 402 for processing.

[0103] The first material 310 in the ceramic plate 402 (e.g., alumina) has a negative temperature coefficient of resistance (TOR). Due to the negative TOR, the resistance of the first material 310 in the ceramic plate 402 decreases as the temperature of the ceramic plate 302 increases during substrate processing as shown in FIG. 9.

[0104] Additionally, the ceramic plate 402 comprises an insulating layer 420. The insulating layer 420 comprises a layer of a second dielectric material that is different than the first material 310 (e.g., alumina). The second dielectric material of the insulating layer 420 has lower TOR slope than the first material 310. The second dielectric material of the insulating layer 420 can be porous or solid.

[0105] The insulating layer 420 is disposed in the first material 310 of the ceramic plate 402. The insulating layer 420 is disposed above the clamping electrodes 304 in the first material 310 of the ceramic plate 402. The insulating layer 420 is disposed in the ceramic plate 402 between the clamping electrodes 304 and a top surface of the ceramic plate 402 on which the substrate 406 lies.

[0106] The insulating layer 420 is disposed at a predetermined distance above the clamping electrodes 304. The distance at which the insulating layer 420 is disposed above the clamping electrodes 304 is a design parameter. The insulating layer 420 is disposed at a predetermined distance below the top surface of the ceramic plate 402.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAThe distance at which the insulating layer 420 is disposed below the top surface of the ceramic plate 402 is a design parameter. The insulating layer 420 has a predetermined thickness (height) measured along a vertical axis of the ESC 400. The thickness (height) of the insulating layer 420 is a design parameter. For example, a layer in the ESC 400 may have a thickness of about 450 urn.

[0107] The distances of the insulating layer 420 above the clamping electrodes 304 and below the top surface of the ceramic plate 402 and the thickness (height) of the insulating layer 420 are selected such that the insulating layer 420 is away from the ionization region above the substrate 406. An area (e.g., diameter) of the insulating layer 420 is greater than or equal to an area (e.g., diameter) of the clamping electrodes 304. In some examples, the area of the insulating layer 420 can be slightly less than the area of the clamping electrodes 304. The area of the insulating layer 420 is also a design parameter.

[0108] The resistance of the first material 310 shown at 412 and the resistance of the insulating layer 320 shown at 414 are in series. As the temperature of the ceramic plate 402 increases during substrate processing, the resistance of the first material 310 decreases due to the negative TCR of the first material 310. However, since the second dielectric material of the insulating layer 420 has a lower TCR slope than the first material 310, the insulating layer 420 exhibits a more dominant resistance than the first material 310 of the ceramic plate 402.

[0109] Specifically, due to the low TCR, the resistance of the second dielectric material of insulating layer 420 is more stable regardless of the variation (e.g., increase) in the temperature of the ceramic plate 402 and becomes the dominant resistance. This results in a smaller overall TCR slope for the ceramic plate 402 comprising the combination of the first material 310 and the insulating layer 420 than when the ceramic plate is solely made of the first material 310 (e.g., the ceramic plate 302 shown in FIGS. 3-5). The insulating layer 420 acts as an insulator layer that can block charges from migrating to the top surface of the ceramic plate 402, which solves the de-chucking problem associate with the ceramic plate 302 shown in FIGS. 3-5.

[0110] If the second dielectric material of the insulating layer 420 is porous, the porosity of the material needs to be uniform to ensure no impact on the clamping process. Unlike the gas-filled insulating layer 320, the design of the insulating layer 420 is fixed (i.e. , not changeable once implemented) since the porosity of the second dielectric material is fixed and cannot be changes like the gas pressure in the insulating layer 320.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAAccordingly, the tuning parameter provided by the gas-filled gap layer is unavailable in the second design (in the insulating layer 420).THIRD DESIGN

[0111] FIG. 8 shows a third design of the ceramic plate using the dominant resistance approach according to the present disclosure. FIG. 8 shows a third way of implanting the insulating layer in the ceramic plate. The third design is called a reverse TOR approach, which is described below in detail.

[0112] In the third design, an ESC 500 comprises a ceramic plate 502 disposed on a metallic baseplate, which is omitted but is similar to the baseplates 32 and 108 shown in FIGS. 1 and 2, respectively. In the ESC 500 shown in FIG. 8, the heater is also omitted but is presumed to be present in the ESC 500, and only the clamping electrodes are shown to focus on how the second design of the ceramic plate solves the de-chucking problem. The ESC 500 can be used in the substrate processing systems 10 and 100 shown in FIGS. 1 and 2, respectively. The ESC 500 does not have the de-chucking issues at elevated temperatures.

[0113] The ESC 500 comprises the ceramic plate 502 in which one or more clamping electrodes 304-1 , 304-2 (collectively called the clamping electrodes 304) are embedded. For example, the clamping electrodes 304 can comprise monopolar or bipolar electrodes. The ceramic plate 502 comprises the first ceramic (dielectric) material (e.g., alumina) 310. The clamping electrodes 304 are embedded in the first material 310 in the ceramic plate 502. The ceramic plate 502 is disposed on a baseplate (not shown) made of a metallic material (e.g., aluminum or an alloy of aluminum). A substrate 506 is arranged on a top surface of the ceramic plate 502 for processing.

[0114] The first material 310 in the ceramic plate 502 (e.g., alumina) has a negative temperature coefficient of resistance (TOR). Due to the negative TOR, the resistance of the first material 310 in the ceramic plate 502 decreases as the temperature of the ceramic plate 302 increases during substrate processing as shown in FIG. 9.

[0115] Additionally, a temperature compensating layer 520 is deposited (or coated) on the clamping electrodes 304 to compensate for resistance changes in the first material 310 of the ceramic plate 502. Alternatively, the temperature compensating layer 520 can be added to the ceramic plate 502 above (i.e., on top of) the clamping electrodes 304 to compensate for resistance changes in the first material 310 of the ceramic plate 502. TheAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAtemperature compensating layer 520 is disposed in the ceramic plate 502 between the clamping electrodes 304 and a top surface of the ceramic plate 502 on which the substrate 506 lies.

[0116] The temperature compensating layer 520 comprises a second dielectric material that is different than the first material 310 of the ceramic plate 502. Specifically, the second dielectric material of the temperature compensating layer 520 has a positive TCR as shown in FIG. 10, which compensates for the negative TCR of the first material 310 (e.g., alumina) as shown in FIG. 11. The second dielectric material of the temperature compensating layer 520 can be selected such that the overall TCR of the ceramic plate 502 is relatively flat (i.e., the overall resistance of the ceramic plate 502 is relatively unchanged) over the temperature range of the process as shown in FIG. 11.

[0117] The temperature compensating layer 520 has a predetermined thickness (height) measured along a vertical axis of the ESC 500. The thickness (height) of the temperature compensating layer 520 is a design parameter. The thickness (height) of the temperature compensating layer 520 is selected such that the temperature compensating layer 520 is away from the ionization region above the substrate 506. For example, a layer in the ESC 500 may have a thickness of about 450 urn. An area (e.g., diameter) of the temperature compensating layer 520 is equal to an area (e.g., diameter) of the clamping electrodes 304. In some examples, the area of the temperature compensating layer 520 can be slightly less or slightly greater than the area of the clamping electrodes 304. The area of the temperature compensating layer 520 is also a design parameter.

[0118] The resistance of the first material 310 shown at 512 and the resistance of the temperature compensating layer 520 shown at 514 are in series. As seen in FIGS. 10 and 11 , as the temperature of the ceramic plate 502 increases during substrate processing, the resistance of the first material 310 decreases due to the negative TCR of the first material 310. However, since the second dielectric material of the temperature compensating layer 520 has a positive TCR slope, the resistance of the second dielectric material of the temperature compensating layer 520 increases as the temperature of the ceramic plate 502 increases during substrate processing. The increase in resistance of the temperature compensating layer 520 compensates for the decrease in resistance of the first material 310 of the ceramic plate 502.

[0119] Accordingly, the overall combined resistance of the first material 310 and the second dielectric material of the temperature compensating layer 520 (i.e., the netAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAresistance of the ceramic plate 502) remains relatively unchanged over the range of temperature of the process being performed on the substrate 506. Consequently, the combination of the first material 310 and the temperature compensating layer 520 continues to function as an insulator layer that can block charges from migrating to the top surface of the ceramic plate 502, which solves the de-chucking problem associate with the ceramic plate 302 shown in FIGS. 3-5.

[0120] As with the second design, unlike the gas-filled insulating layer 320, the design of the temperature compensating layer 520 is fixed (i.e., not changeable once implemented) and cannot be changes like the gas pressure in the insulating layer 320. Accordingly, the tuning parameter provided by the gas-filled gap layer is unavailable in the third design (in the temperature compensating layer 520).

[0121] The foregoing description is merely illustrative in nature and is not intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent upon a study of the drawings, the specification, and the following claims.

[0122] It should be understood that one or more steps within a method may be executed in different order (or concurrently) without altering the principles of the present disclosure. Further, although each of the examples is described above as having certain features, any one or more of those features described with respect to any one of the examples of the disclosure can be implemented in and / or combined with features of any of the other examples, even if that combination is not explicitly described. In other words, the described examples are not mutually exclusive, and permutations of one or more examples with one another remain within the scope of this disclosure.

[0123] Spatial and functional relationships between elements (for example, between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including “connected,” “engaged,” “coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and “disposed.” Unless explicitly described as being “direct,” when a relationship between first and second elements is described in the above disclosure, that relationship can be a direct relationship where no other intervening elements are present between the first and second elements, but can also be an indirect relationship where one or more intervening elements are present (either spatially or functionally) between the first andAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAsecond elements. As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A OR B OR C), using a non-exclusive logical OR, and should not be construed to mean “at least one of A, at least one of B, and at least one of C.”

[0124] In some implementations, a controller is part of a system, which may be part of the above-described examples. Such systems can comprise semiconductor processing equipment, including a processing tool or tools, chamber or chambers, a platform or platforms for processing, and / or specific processing components (a substrate support, a gas flow system, etc.). These systems may be integrated with electronics for controlling their operation before, during, and after processing of a semiconductor wafer or substrate.

[0125] The electronics may be referred to as the “controller,” which may control various components or subparts of the system or systems. The controller, depending on the processing requirements and / or the type of system, may be programmed to control any of the processes disclosed herein, including the delivery of processing gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, positional and operation settings, wafer transfers into and out of a tool and other transfer tools and / or load locks connected to or interfaced with a specific system.

[0126] Broadly speaking, the controller may be defined as electronics having various integrated circuits, logic, non-transitory memory, and / or software that receive instructions, issue instructions, control operation, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors, or microcontrollers that execute program instructions (e.g., software).

[0127] Program instructions may be instructions communicated to the controller in the form of various individual settings (or program files), defining operational parameters for carrying out a particular process on or for a semiconductor wafer or to a system. The operational parameters may, in some examples, be part of a recipe defined by process engineers to accomplish one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA

[0128] The controller, in some implementations, may be a part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller may be in the “cloud” or all or a part of a fab host computer system, which can allow for remote access of the wafer processing. The computer may enable remote access to the system to monitor current progress of fabrication operations, examine a history of past fabrication operations, examine trends or performance metrics from a plurality of fabrication operations, to change parameters of current processing, to set processing steps to follow a current processing, or to start a new process.

[0129] In some examples, a remote computer (e.g., a server) can provide process recipes to a system over a network, which may include a local network or the Internet. The remote computer may include a user interface that enables entry or programming of parameters and / or settings, which are then communicated to the system from the remote computer. In some examples, the controller receives instructions in the form of data, which specify parameters for each of the processing steps to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control.

[0130] Thus, as described above, the controller may be distributed, such as by comprising one or more discrete controllers that are networked together and working towards a common purpose, such as the processes and controls described herein. An example of a distributed controller for such purposes would be one or more integrated circuits on a chamber in communication with one or more integrated circuits located remotely (such as at the platform level or as part of a remote computer) that combine to control a process on the chamber.

[0131] Without limitation, example systems may include a plasma etch chamber or module, a deposition chamber or module, a spin-rinse chamber or module, a metal plating chamber or module, a clean chamber or module, a bevel edge etch chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an atomic layer deposition (ALD) chamber or module, an atomic layer etch (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, and any other semiconductor processing systemsAttorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POAthat may be associated or used in the fabrication and / or manufacturing of semiconductor wafers.

[0132] As noted above, depending on the process step or steps to be performed by the tool, the controller might communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout a factory, a main computer, another controller, or tools used in material transport that bring containers of wafers to and from tool locations and / or load ports in a semiconductor manufacturing factory.

Claims

Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POACLAIMSWhat is claimed is:

1. A substrate support comprising:a baseplate made of a metallic material; anda ceramic plate disposed on the baseplate to support a substrate;wherein the ceramic plate comprises:a first dielectric material having a first temperature coefficient of resistance; one or more clamping electrodes disposed in the first dielectric material to clamp the substrate; anda layer having a second temperature coefficient of resistance disposed in the first dielectric material between the one or more clamping electrodes and a substratefacing surface of the ceramic plate.

2. The substrate support of claim 1 wherein the layer comprises a second dielectric material that is different than the first dielectric material.

3. The substrate support of claim 1 wherein the layer comprises a cavity filled with air.

4. The substrate support of claim 1 wherein the layer comprises a cavity, the substrate support further comprising a conduit connected to the layer to supply a gas to the cavity in the layer.

5. The substrate support of claim 4 further comprising a gas supply connected to the conduit to supply the gas at a selected pressure.

6. The substrate support of claim 1 wherein:the first temperature coefficient of resistance of the first dielectric material is negative; andthe second temperature of coefficient of the layer is less negative than the first temperature coefficient of resistance.

7. The substrate support of claim 1 wherein the layer comprises a second dielectric material and wherein the layer is porous.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA8. The substrate support of claim 1 wherein:the first temperature coefficient of resistance of the first dielectric material is negative; andthe second temperature of coefficient of the layer is positive.

9. The substrate support of claim 8 wherein the layer is coated on the one or more clamping electrodes.

10. The substrate support of claim 8 wherein the layer is disposed on the one or more clamping electrodes.

11. The substrate support of claim 1 wherein the layer is disposed in the first dielectric material at a predetermined distance from the one or more clamping electrodes.

12. The substrate support of claim 1 wherein the layer is disposed in the first dielectric material at a predetermined distance from the substrate-facing surface of the ceramic plate.

13. The substrate support of claim 1 wherein the layer has a predetermined thickness.

14. The substrate support of claim 1 wherein an area of the layer is greater than or equal to an area of the one or more clamping electrodes.

15. The substrate support of claim 1 further comprising:one or more heaters disposed in the ceramic plate; andone or more cooling channels disposed in the baseplate.

16. A substrate support comprising:a first layer of a first dielectric material having a first temperature coefficient of resistance;one or more clamping electrodes disposed in the first layer; anda second layer having a second temperature coefficient of resistance disposed in the first layer above the one or more clamping electrodes.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA17. The substrate support of claim 16 wherein the second layer comprises a second dielectric material that is different than the first dielectric material.

18. The substrate support of claim 16 wherein the second layer comprises a cavity filled with air.

19. The substrate support of claim 16 wherein the second layer comprises a cavity, the substrate support further comprising a conduit connected to the second layer to supply a gas to the cavity in the layer.

20. The substrate support of claim 19 further comprising a gas supply connected to the conduit to supply the gas at a selected pressure.

21. The substrate support of claim 16 wherein:the first temperature coefficient of resistance of the first layer is negative; and the second temperature of coefficient of the second layer is less negative than the first temperature coefficient of resistance.

22. The substrate support of claim 16 wherein the second layer comprises a second dielectric material and wherein the second layer is porous.

23. The substrate support of claim 16 wherein:the first temperature coefficient of resistance of the first layer is negative; and the second temperature of coefficient of the second layer is positive.

24. The substrate support of claim 23 wherein the second layer is coated on the one or more clamping electrodes.

25. The substrate support of claim 23 wherein the second layer is disposed on the one or more clamping electrodes.

26. The substrate support of claim 16 wherein the second layer is disposed in the first layer at a predetermined distance from the one or more clamping electrodes.

27. The substrate support of claim 16 wherein the second layer is disposed in the first layer at a predetermined distance above the one or more clamping electrodes.Attorney Docket No. 11943-1 WOHDP Ref. No. 15545-001295-WO-POA28. The substrate support of claim 16 wherein the second layer has a predetermined thickness.

29. The substrate support of claim 16 wherein an area of the second layer is greater than or equal to an area of the one or more clamping electrodes.

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