High temperature pedestal with extended electrostatic chuck electrode

Abstract

The substrate support configured to support a substrate having a diameter D includes first and second inner electrodes, each D-shaped and defining a first outer diameter smaller than D, and configured to be connected to an electrostatic chucking voltage to clamp the substrate to the substrate support. The outer electrode includes a ring-shaped outer portion surrounding the first and second inner electrodes and a central portion passing between the first and second inner electrodes and connecting to either side of the inner diameter of the ring-shaped outer portion. The inner diameter of the ring-shaped outer portion is larger than diameter D such that the inner diameter of the ring-shaped outer portion and an intersection of the central portion and the ring-shaped outer portion are located radially outside of diameter D of the substrate.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of U.S. Provisional Application No. 63 / 086,561, filed October 1, 2020, the entire disclosure of which is incorporated herein by reference.

[0002] The present disclosure relates to a substrate support pedestal in a substrate processing system. [Background technology]

[0003] The Background Art set forth herein is intended to generally present the content of the present disclosure. Please note that the information set forth in this section is presented to provide those skilled in the art with the content of the subject matter disclosed below and should not be considered admitted prior art. Specifically, the inventions of the presently named inventors are not admitted expressly or impliedly as prior art to the present disclosure to the extent that they are described in this Background Art section and in a descriptive manner that does not constitute prior art at the time of filing.

[0004] Substrate processing systems may be used to process substrates, such as semiconductor wafers. Examples of substrate processing include etching, deposition, photoresist removal, etc. During processing, the substrate may be placed on a substrate support, such as an electrostatic chuck, and one or more process gases may be introduced into the processing chamber.

[0005] One or more process gases may be supplied to the processing chamber by a gas delivery system. In some systems, the gas delivery system includes a manifold connected by one or more conduits to a showerhead located within the processing chamber. In some examples, deposition processes such as chemical vapor deposition (CVD), plasma-enhanced CVD (PECVD), atomic layer deposition (ALD), etc., are used to deposit materials on the substrate. Summary of the Invention

[0006] The substrate support configured to support a substrate having a diameter D includes a first inner electrode and a second inner electrode, each of which is D-shaped and defines a first outer diameter smaller than D, and is configured to be connected to an electrostatic chucking (ESC) voltage to clamp the substrate to the substrate support during processing. The outer electrode includes a ring-shaped outer portion surrounding the first and second inner electrodes and a central portion passing between the first and second inner electrodes and connecting to either side of the inner diameter of the ring-shaped outer portion. The inner diameter of the ring-shaped outer portion is larger than diameter D such that the inner diameter of the ring-shaped outer portion and an intersection of the central portion and the ring-shaped outer portion are located radially outside of diameter D of the substrate.

[0007] In other features, the substrate support further includes a gap defined between a first outer diameter defined by the first inner electrode and the second inner electrode and an inner diameter of the ring-shaped outer portion. The gap is located below and overlaps the outer edge of the substrate. The gap has a width of 2.2 to 7.5 mm. The inner diameter of the ring-shaped outer portion is less than 1.0 mm larger than the diameter D of the substrate. The inner diameter of the ring-shaped outer portion is 300.4 to 305 mm. The first outer diameter defined by the first inner electrode and the second inner electrode is 290 to 296 mm.

[0008] In other features, the substrate support further comprises a pocket on a first surface of the substrate support. The pocket is configured to hold a substrate. The substrate support further comprises a substrate disposed in the pocket. A diameter of the pocket is 302 to 310 mm. An inner diameter of the ring-shaped outer portion overlaps the pocket.

[0009] A method for depositing a hard mask film on a substrate having a diameter D includes placing the substrate on a substrate support in a processing chamber. The substrate support includes first and second inner electrodes, each D-shaped and defining a first outer diameter smaller than D; an outer electrode including a ring-shaped outer portion surrounding the first and second inner electrodes; and a central portion passing between the first and second inner electrodes and connecting to both sides of the inner diameter of the ring-shaped outer portion. The inner diameter of the ring-shaped outer portion is larger than the inner diameter of the ring-shaped outer portion and the diameter D such that an intersection of the inner diameter of the ring-shaped outer portion and the central portion and the ring-shaped outer portion is located radially outside the diameter D of the substrate. The method further includes connecting the first and second inner electrodes to an electrostatic chuck (ESC) voltage to clamp the substrate to the substrate support and depositing a hard mask film on the substrate. Depositing the hard mask film includes generating a plasma in the processing chamber.

[0010] In another feature, the method further includes defining a gap between a first outer diameter defined by the first inner electrode and the second inner electrode and an inner diameter of the ring-shaped outer portion. The gap is located below and overlaps the outer edge of the substrate. The gap has a width of 2.2 to 7.5 mm. The inner diameter of the ring-shaped outer portion is less than 1.0 mm larger than the diameter D of the substrate. The inner diameter of the ring-shaped outer portion is 300.4 to 305 mm. The first outer diameter defined by the first inner electrode and the second inner electrode is 290 to 296 mm.

[0011] In another feature, the method further includes placing the substrate in a pocket in the first surface of the substrate support, the pocket having a diameter of 302 to 310 mm, and the inner diameter of the ring-shaped outer portion overlapping the pocket.

[0012] The substrate support configured to support a substrate includes a first inner electrode and a second inner electrode, each D-shaped and configured to be connected to an electrostatic chuck (ESC) voltage to clamp the substrate to the substrate support during processing. The outer electrode includes a ring-shaped outer portion surrounding the first inner electrode and the second inner electrode and a central portion connecting to both sides of the inner diameter of the ring-shaped outer portion. The outer electrode is not coplanar with the first inner electrode and the second inner electrode.

[0013] In other features, the outer electrode is positioned below the first inner electrode and the second inner electrode. The central portion includes a plurality of radial conductors extending outward from the conductive rod to connect to the ring-shaped outer portion. The plurality of radial conductors includes two or more radial conductors. The plurality of radial conductors includes four or more radial conductors.

[0014] The substrate support configured to support a substrate includes a first inner electrode and a second inner electrode, each of which is D-shaped. The first inner electrode and the second inner electrode are configured to be connected to an electrostatic chucking (ESC) voltage to clamp the substrate to the substrate support during processing. The outer electrode includes a ring-shaped outer portion surrounding the first inner electrode and the second inner electrode, a central portion located below the ring-shaped outer portion, a ring surrounding the central portion, being coplanar with the central portion and electrically connected to the central portion, and at least one vertical portion electrically connecting the ring to the ring-shaped outer portion.

[0015] In other features, the central portion includes a plurality of radial conductors extending outward from the conductive bar to connect to the ring, the plurality of radial conductors including two or more radial conductors, the plurality of radial conductors including four or more radial conductors.

[0016] 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 for purposes of illustration only and are not intended to limit the scope of the disclosure. [Brief explanation of the drawings]

[0017] The present disclosure will become better understood from the detailed description and the accompanying drawings.

[0018] [Figure 1] FIG. 1 is a functional block diagram of an exemplary substrate processing system according to the present disclosure.

[0019] [Figure 2A] 1 illustrates a substrate support comprising an exemplary electrostatic chuck (ESC) electrode according to the present disclosure.

[0020] [Figure 2B] Plan view of the ESC electrodes in Figure 2A.

[0021] [Figure 3] 1 is an isometric view of an exemplary ring-shaped outer electrode according to the present disclosure.

[0022] [Figure 4] 1 illustrates exemplary method steps for performing a deposition process using a substrate support according to the present disclosure.

[0023] [Figure 5A] 10 is a substrate support including another exemplary ESC electrodes according to the present disclosure.

[0024] [Figure 5B] Plan view of the ESC in Figure 5A.

[0025] [Figure 5C] 10 is a substrate support including another exemplary ESC electrodes according to the present disclosure.

[0026] [Figure 5D] FIG. 10 is a plan view of another ESC electrode according to the present disclosure.

[0027] [Figure 5E] FIG. 5E is a plan view showing another exemplary arrangement of the ESC electrodes in FIG. 5D .

[0028] [Figure 5F] FIG. 5D and 5E are isometric views of the exemplary ring-shaped outer electrode.

[0029] [Figure 6A] 10 is a substrate support including another exemplary ESC electrodes according to the present disclosure.

[0030] [Figure 6B] 6B is an isometric view of the exemplary ring-shaped outer electrode of FIG. 6A.

[0031] In the drawings, reference numbers may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION OF THE INVENTION

[0032] In film deposition processes (e.g., chemical vapor deposition (CVD), plasma-enhanced CVD (PECVD), atomic layer deposition (ALD)), various properties of the deposited film vary depending on their spatial distribution (i.e., x-y coordinates in the horizontal plane) and azimuthal distribution. For example, substrate processing tools may have different specifications for film thickness non-uniformity (NU). Film thickness NU may be measured as the full range, half range, and / or standard deviation of a set of measurements taken at a given location on the surface of a semiconductor substrate.

[0033] Some exemplary processes with high aspect ratios may be more sensitive to film thickness NU. For example, in the fabrication of 3D NAND memory, a hardmask film (e.g., a high-temperature ashable hardmask) may be deposited to pattern channel holes in the slits between alternating film stacks. Accurate etching of the high-aspect ratio channel holes will require the hardmask film to be ultra-flat (i.e., a thickness NU fraction of the substrate half-area of ​​≦0.7% range).

[0034] In some examples, NU can also be reduced by addressing its direct cause. NU may be reduced by introducing counter-NU to compensate and offset existing NU. In other examples, material may be intentionally deposited and / or removed non-uniformly to compensate for known non-uniformities in other (e.g., previous or subsequent) steps in the process.

[0035] The deposition rate may depend in part on the temperatures of the substrate and the substrate support. Thus, a temperature N (i.e., a temperature difference across the substrate) will result in a different deposition rate and, correspondingly, a film thickness N. The substrate processing system may implement various temperature control methods to control the temperature of the substrate to minimize N. For example, the substrate support may include a heater layer. The heater layer may include one or more zones, each of which may be controlled to maintain a desired temperature of the substrate support, and accordingly, the substrate.

[0036] In other examples, other features of the substrate support can cause and / or increase deposition NU. For example, one or more electrostatic chuck (ESC) electrodes are disposed on a substrate support configured as an ESC. A voltage is supplied to the electrodes to clamp the substrate to the substrate support. The substrate support may include two or more electrodes (e.g., one or more inner clamping electrodes surrounded by an outer guard electrode). The shape of the electrodes may cause an increase in plasma density (e.g., a plasma "hot spot") above a particular portion of the substrate. For example, the outer electrode may include a ring-shaped portion (a guard ring or guard electrode) and a central portion (e.g., one or more radial conductors, such as a central strip or band) that bisects the ring portion. A plasma hot spot may occur above the intersection of the ring-shaped portion and the central portion. The local plasma hot spot results in a non-uniform plasma distribution and, accordingly, a high-angle deposition NU.

[0037] The arrangement of the ESC electrodes according to the present disclosure eliminates plasma hot spots above the substrate caused by the shape of the electrodes. For example, the arrangement of the ESC electrodes includes two D-shaped inner electrodes and an outer electrode including a ring-shaped portion. The inner electrode and the outer electrode may include molybdenum. The central portion (e.g., a central strip) connects to both sides of the inner diameter of the ring-shaped portion through a gap between the D-shaped inner electrodes. For example, the central portion corresponds to two collinear radial conductors extending outward to connect to the outer electrode. An intersection (i.e., a contact point or connection point) between the ring-shaped portion and the central portion is located radially outside the substrate. For example, the inner diameter of the ring-shaped portion is larger than the outer diameter of the substrate. Therefore, plasma hot spots generated at the intersection points between the ring-shaped portion and the central portion are not formed above the substrate and do not affect the deposition rate. Such azimuthal deposition uniformity is improved.

[0038] Additionally, the ESC voltage may be applied to the D-shaped inner electrode, but not to the outer electrode. If the outer electrode is below the outer edge of the substrate, the chucking force will not be applied to the edge of the substrate. Thus, increasing the diameter or circumference defined by the D-shaped electrode relative to the diameter of the substrate extends the chucking force to the edge of the substrate, allowing the pedestal to accommodate highly curved substrates.

[0039] In another example, the outer electrode is positioned in a different plane (i.e., not coplanar) than the D-shaped inner electrode. For example, the outer electrode is positioned lower than the inner electrode. The radial conductors of the central portion may have a width smaller than, equal to, or larger than the width of the gap between the D-shaped inner electrodes. The radial conductors may or may not be parallel (i.e., coaxial) with the gap between the D-shaped inner electrodes. The ring-shaped portion and the central portion may be formed in a single process (e.g., a single sintering process). In this way, the intersection between the central portion and the ring-shaped portion is moved below the inner electrode in a direction away from the first surface of the substrate. Accordingly, the generation of plasma hot spots above the substrate is reduced or eliminated. Furthermore, the impedance of the outer electrode may be adjusted by placing the outer electrode at a different height relative to the first surface of the substrate support and the inner electrode.

[0040] Additionally, the central portion may include two or more radial conductors (e.g., three, four, or more) extending radially outward from a central point toward the ring portion (e.g., corresponding to the location of the conductive bars). In this manner, electrical connections to the ring portion are distributed among a larger number (i.e., multiple) of radial conductors. This reduces both the impedance and localized heating of the ring portion caused by individual radial conductors.

[0041] In another example, the ring-shaped portion is disposed in the same plane (i.e., coplanar) or a different plane (i.e., not coplanar) as the D-shaped inner electrode. The central portion is disposed in a plane below (i.e., not coplanar) the ring-shaped portion and the D-shaped inner electrode. For example, the central portion is disposed below the ring-shaped portion and the inner electrode. The radial conductors of the central portion may have a width smaller than, the same as, or larger than the gap between the D-shaped inner electrodes. The radial conductors may or may not be parallel (i.e., coaxial) with the gap between the D-shaped inner electrodes. The central portion may include two, three, four, or more radial conductors. The radial conductors are electrically connected to the ring-shaped portion via their respective vertical portions.

[0042] 1, an example of a substrate processing system 100 is shown that includes a substrate support (e.g., pedestal) 104 in accordance with the present disclosure. The substrate support 104 is disposed within a processing chamber 108. A substrate 112 is disposed on the substrate support 104 during processing.

[0043] Gas supply system 120 includes gas sources 122-1, 122-2, ..., and 122-N (collectively, gas sources 122) connected to valves 124-1, 124-2, ..., and 124-N (collectively, valves 124) and mass flow controllers 126-1, 126-2, ..., and 126-N (collectively, MFCs 126). MFCs 126 control the flow of gas from gas sources 122 to a manifold 128 where the gases are mixed. The output of manifold 128 is supplied by optional pressure regulator 132 to a gas distribution device, such as a multi-injector showerhead 140.

[0044] The substrate support 104 according to the present disclosure is configured to function as an ESC. For example, the substrate support 104 includes one or more ESC electrodes, such as one or more inner (e.g., D-shaped) electrodes 144 and outer (e.g., ring-shaped) electrodes 148. The inner electrode 144 and the outer electrode 148 are configured such that a gap 152 therebetween is located below (i.e., overlaps with) the outer edge of the substrate 112, as described in more detail below. For example, the inner diameter of the outer electrode 148 is larger than the outer diameter of the substrate 112. Furthermore, the intersection / connection point (not shown in FIG. 1 ) of the outer electrode 148 and the central portion is located radially outside the outer diameter of the substrate 112.

[0045] In some examples, the temperature of the substrate support 104 may be controlled using a heater layer, such as a resistive heater 160. The substrate support 104 may include a coolant channel 164. Cooling fluid is supplied to the coolant channel 164 from a fluid reservoir 168 and a pump 170. A pressure sensor 172 may be disposed in the manifold 128 to measure pressure. A valve 178 and a pump 180 may be used to evacuate reactants from the processing chamber 108 and / or to control the pressure within the processing chamber 108.

[0046] The controller 182 includes a dose controller 184 that controls the dosage provided by the multi-injector showerhead 140. The controller 182 also controls the gas supply from the gas supply system 120. The controller 182 controls the pressure in the processing chamber and / or the evacuation of reactants using valves 178 and pumps 180. The controller 182 controls the temperature of the substrate support 104 and the substrate 112 based on temperature feedback (e.g., from a sensor (not shown) on the substrate support and / or a sensor (not shown) measuring a coolant temperature). The controller 182 controls the selective supply of power to the inner electrode 144 to clamp the substrate 112 to the substrate support 104. The outer electrode 148 may be connected to a reference potential, such as ground.

[0047] In some examples, the substrate processing system 100 may be configured to perform etching of the substrate 112 in the same processing chamber 108. Accordingly, the substrate processing system 100 may include an RF generating system 188 configured to generate and provide RF power (e.g., as a voltage source, a current source, etc.) to a first electrode (e.g., a base plate of the illustrated substrate support 104) and a second electrode (e.g., the showerhead 140). For illustrative purposes only, the output of the RF generating system 188 is described herein as an RF voltage.

[0048] The first electrode and the second electrode may be DC-grounded, AC-grounded, or floating. For example, the RF generation system 188 may include an RF generator 192 configured to generate an RF voltage supplied by a matched distribution network 196 to generate a plasma in the processing chamber 108 and etch the substrate 112. In other examples, the plasma may be inductively or remotely generated. As shown for illustrative purposes, the RF generation system 188 corresponds to a capacitively coupled plasma (CCP) system, although the principles of the present disclosure may be used with other suitable systems (by way of example only, a transformer coupled plasma (TCP) system, a CCP cathode system, a remote microwave plasma generation and supply system, etc.).

[0049] 2A and 2B , an exemplary substrate support 200 according to the present disclosure includes two D-shaped (e.g., first and second) inner electrodes 204 and a ring-shaped outer electrode 208. For example, the inner electrodes 204 correspond to ESC clamp electrodes. The outer electrodes 208 correspond to ESC guard electrodes. The inner electrodes 204 are each connected to an ESC voltage having an opposite polarity (e.g., corresponding to the controller 182) to generate a clamp voltage across the substrate support 200. Conversely, the outer electrode 208 is connected to a reference potential (e.g., ground) to function as a guard ring. In various examples, the ESC voltages may be pulsed or continuous wave voltages, may be RF or DC voltages, may be the same or different for each electrode 204, may be provided by the same or different sources, and may have the same or different frequencies.

[0050] A first (e.g., top) surface 212 of the substrate support 200 includes a pocket 216 configured to hold a substrate 220 disposed on the substrate support 200. A gap 224 is defined between the inner electrode 204 (e.g., an outer diameter 226 defined by an outer semicircular edge of the inner electrode 204) and an inner edge or inner diameter 228 of the outer electrode 208.

[0051] The gap 224 is located below the outer edge or diameter 232 of the substrate 220. Furthermore, the inner diameter 228 of the outer electrode 208 is located radially outward of the outer diameter 232 of the substrate 220. That is, the inner diameter 228 of the outer electrode 208 is larger than the outer diameter 232 of the substrate. For example, the substrate 220 may be a standard size (i.e., diameter D), such as 300 mm. The pocket 216 may have a diameter larger than 300 mm (e.g., 302-310 mm) to accommodate the substrate 220. The inner diameter 228 of the outer electrode 208 may be 300.4-305 mm. The outer diameter 226 of the inner electrode 204 may be 290-296 mm. As shown, the inner diameter 228 of the outer electrode 208 overlaps the pocket 216. In other examples, the inner diameter 228 of the outer electrode 208 is located radially outward of (i.e., does not overlap with) the pocket 216. The gap 224 may have a width of 2.2 to 7.5 mm.

[0052] The inner diameter 228 of the outer electrode 208 is only slightly larger than the outer diameter 232 of the substrate 220 (e.g., less than 1.0 mm or between 0.2 and 1.0 mm). For example, if the inner diameter 228 of the outer electrode 208 is too large (i.e., larger than the outer diameter 232 of the substrate 220), the DC electric field may leak from the substrate support 200 into the RF plasma formed above the substrate 220, potentially altering the RF plasma behavior. That is, if the inner diameter 228 is too large, the outer electrode 208 will not adequately suppress the DC electric field leakage and will not function properly as a guard electrode. Conversely, if the outer diameter 226 of the inner electrode 204 is too small, the ESC voltage applied to the inner electrode 204 will not extend to the outer diameter 232 of the substrate 220, and the edge of the substrate 220 will not be clamped to the substrate support 104. Thus, the inner diameter 228 of the outer electrode 208 and the outer diameter 226 of the inner electrode 204 are selected to optimize suppression of DC electric field leakage while preventing plasma hot spots above the outer diameter 232 of the substrate 220. Furthermore, as the inner diameter 228 increases, the outer diameter 226 of the inner electrode 204 also increases accordingly to maximize the clamping force on the edge of the substrate 220 relative to the substrate support 104.

[0053] A central strip or central portion 236 (e.g., comprising two radial conductors) passes between the inner electrode 204 and connects to both sides of the ring-shaped outer electrode 208. For example, the central portion 236 bisects the central opening of the outer electrode 208, defining two D-shaped openings. An inner electrode 204 is disposed within each D-shaped opening. A plasma hot spot (i.e., a region of high plasma density) may occur above the intersection (e.g., 240 in the figure) between the central portion 236 and the outer electrode 208. Therefore, the intersection 240 is located radially outside the outer diameter 232 of the substrate 220. That is, because the inner diameter 228 of the outer electrode 208 is located radially outside the outer diameter 232 of the substrate 220, the intersection 240 where the central portion 236 meets the inner diameter 228 of the outer electrode 208 is also located radially outside the outer diameter 232 of the substrate 220.

[0054] Thus, the plasma hot spot created by the intersection 240 between the central portion 236 and the outer electrode 208 occurs radially outside the outer diameter 232 of the substrate 220. Therefore, the plasma hot spot does not result in film deposition NU on the substrate 220.

[0055] 3, an exemplary ring-shaped outer electrode 300 according to the present disclosure is shown. The outer electrode 300 comprises an annular outer portion 304 and a central strip or central portion 308. The central portion 308 (and, accordingly, the outer portion 304) is a radial conductor connected to a reference voltage or potential (e.g., ground) via a conductive wire or rod 312. The central portion 308 thus electrically connects the annular outer portion 308 to the conductive rod 312.

[0056] The central portion 308 functions as a conductive element. Furthermore, the central portion 308 may be capacitively coupled to a plasma formed above the substrate during plasma processing. Thus, a high pressure region may form at the intersection 316 of the central portion 308 and the outer portion 304. Increasing the inner diameter of the outer portion 304 (and correspondingly, the length of the central portion 308 and the radial position of the intersection 316) so that the inner diameter 320 is larger than the outer diameter of the substrate moves the intersection 316, as described above in FIGS. 2A and 2B , and accordingly, moves the plasma hot spot radially outside the outer diameter of the substrate.

[0057] The inner diameter 320 of the outer portion 304 may increase, but the outer diameter 324 may not. Thus, the cross-sectional width of the outer portion 304 may decrease relative to the other ring-shaped guard electrodes that overlap the substrate. By way of example only, the cross-sectional width of the outer portion 304 may be 15-20 mm.

[0058] Referring now to FIG. 4, an exemplary method 400 for performing a deposition process using a substrate support according to the present disclosure begins at 404. At 408, a substrate having a diameter D is placed in a pocket of the substrate support within a substrate processing chamber. For example, the substrate support corresponds to the substrate support 200 of FIG. 2A and is configured to function as an ESC. The substrate support includes first and second D-shaped inner electrodes, a ring-shaped outer electrode, and a central portion that passes between the first and second inner electrodes and connects to the inner diameter of the ring-shaped outer electrode. The inner diameter of the ring-shaped outer electrode is larger than the diameter D of the substrate (e.g., 0.4-1.0 mm larger than D). At 412, the first and second inner electrodes are energized (e.g., connected to an ESC voltage) to clamp the substrate to the substrate support.

[0059] At 416, a deposition process is performed on the substrate. For example, a hard mask film is deposited on the high aspect ratio features of the substrate. The hard mask film is configured to pattern flow holes in the slits between the alternating film stacks on the substrate. Deposition of the hard mask film includes generating a plasma in the processing chamber. The method 400 ends at 420.

[0060] 5A, 5B, 5C, 5D, and 5E, another exemplary substrate support 500 according to the present disclosure includes two D-shaped (e.g., first and second) inner electrodes 504 and a ring-shaped outer electrode 508. In this example, the outer electrode 508 is disposed in a different plane than the inner electrode 504 (i.e., not coplanar). As shown, the outer electrode 508 is disposed below the inner electrode 504. A first (e.g., top) surface 512 of the substrate support 500 includes a pocket 516 configured to hold a substrate 520 disposed on the substrate support 500. A gap 524 is defined between the inner electrode 504 (e.g., an outer diameter 526 defined by an outer semicircular edge of the inner electrode 504) and an inner end or inner diameter 528 of the outer electrode 508.

[0061] 5A, the gap 524 is located below the outer edge or outer diameter 532 of the substrate 520. Additionally, the inner diameter 528 of the outer electrode 508 is located radially outward of the outer diameter 532 of the substrate 520. That is, the inner diameter 528 of the outer electrode 508 is larger than the outer diameter 532 of the substrate. The inner diameter 528 of the outer electrode 508 overlaps the pocket 516. As shown in another example in FIG. 5C, the inner diameter 528 of the outer electrode 508 overlaps the outer diameter 532 of the substrate 520.

[0062] As shown in FIG. 5B , a central strip or central portion 536 including radial conductors 538-1 and 538-2 passes between the inner electrodes 504 and connects to either side of the ring-shaped outer electrode 508. For example, the central portion 536 bisects the central opening of the outer electrode 508 to define two D-shaped openings. An inner electrode 504 is disposed within each D-shaped opening. The ring-shaped outer electrode 508 and the central portion 536 may be formed in a single process (e.g., a single sintering process). In FIGS. 5A and 5B , an intersection 540 between the central portion 536 and the outer electrode 508 is located radially outside the outer diameter 532 of the substrate 520. Furthermore, in FIGS. 5A and 5B , the width of the gap between the inner electrodes 504 is greater than the width of the central portion 536. Conversely, as shown in FIG. 5C , the width of the gap between the inner electrodes 504 is smaller than the width of the central portion 536. In another example, the width of the gap between the inner electrodes 504 is the same as the width of the central portion 536 .

[0063] As shown in Figures 5D and 5E, the central portion 536 may include two or more radial conductors (e.g., three, four, or more radial conductors) extending radially outward from a center point (e.g., corresponding to the central portion 536) toward the outer electrode 508. Figure 5F shows an isometric view of the outer electrode 508 of Figures 5D and 5E. For example, the central portion 536 may include four radial conductors 538-1, 538-2, 538-3, and 538-4 (collectively, radial conductors 538). In this manner, electrical connections between the conductive rod 544 (shown in Figure 5F) and the ring-shaped outer electrode 508 are distributed among multiple (i.e., two or more) radial conductors 538 to reduce the impedance of the outer electrode 508. Furthermore, localized heating caused by individual radial conductors 538 is reduced.

[0064] As shown in Figure 5B, the radial conductors 538 may be parallel (i.e., coaxial) with the gap between the inner electrodes 504. As shown in Figure 5D, radial conductors 538-1 and 538-2 are parallel to the gap between the inner electrodes 504, and radial conductors 538-3 and 538-4 are not parallel (i.e., perpendicular or orthogonal) to the gap between the inner electrodes 504. Conversely, none of the radial conductors 538 shown in Figure 5E are parallel to the gap between the inner electrodes 504.

[0065] In this manner (as described above in FIGS. 5A-5F ), the intersection of the central portion 536 and the ring-shaped outer electrode 508 is moved below the inner electrode 504, in a direction away from the first surface 512 of the substrate support 500. Thus, the generation of plasma hot spots above the substrate 520 is reduced or eliminated. Furthermore, the impedance of the outer electrode 508 may be adjusted by placing the outer electrode 508 at different heights relative to the first surface 512 of the substrate support 500 and the inner electrode 504.

[0066] 6A and 6B, another exemplary substrate support 600 according to the present disclosure includes two D-shaped (e.g., first and second) inner electrodes 604 and a ring-shaped outer electrode 608. In this example, the outer electrode 608 is disposed in the same plane (i.e., coplanar) as the inner electrode 604 (as shown in FIG. 6A) or in a different plane (i.e., non-coplanar) from the inner electrode 604. Conversely, the central portion 636 is disposed in a different plane (i.e., non-coplanar) from the inner electrode 604 and the outer electrode 608. As shown, the central portion 636 is disposed below the inner electrode 604 and the outer electrode 608.

[0067] The central portion 636 includes radial conductors 638-1, 638-2, 638-3, and 638-4 (collectively, radial conductors 638). While four radial conductors 638 are shown, the central portion 636 may include fewer (e.g., two) or more (e.g., five or more) radial conductors 638. The radial conductors 638 may have a width that is less than, the same as, or greater than the width of the gap between the D-shaped inner electrodes 604. The radial conductors 638 may be parallel (i.e., coaxial) with the gap between the D-shaped inner electrodes 604 (e.g., as shown in FIG. 5D ) or non-parallel (e.g., as shown in FIG. 5E ).

[0068] The radial conductors 638 are connected to the conductive rods 644 and to a ring (e.g., a lower ring) 648 that surrounds the radial conductors 638 and is coplanar with the radial conductors 638. The rings 648 may have a cross-sectional width, inner diameter, and / or outer diameter that is greater than, the same as, or smaller than the cross-sectional width, inner diameter, and / or outer diameter of the outer electrode 608. The rings 648 are connected to the ring-shaped outer electrode 608 through respective vertical portions (e.g., conductor posts, traces, conductor-filled vias, etc.) 652. The vertical portions 652 may comprise the same or different material as the radial conductors 638 and / or the outer electrode 608. The number of vertical portions 652 (e.g., at least one) may be the same as or different from the number of radial conductors 638 (e.g., may be greater or less). Furthermore, although vertical portion 652 is shown to be located at the intersection of radial conductor 638 and ring 648, it may be located at other locations between ring 648 and outer electrode 608 (e.g., at imaginary location 656).

[0069] In this manner, the conductive rods 644 are electrically connected to the outer electrode 608. Furthermore, because the electrical connection between the radial conductors 638 and the outer electrode 608 is moved below the outer electrode 608 and distributed among the multiple vertical portions 652, the occurrence of plasma hot spots above the substrate support 600 is reduced or eliminated.

[0070] The above description is merely exemplary in nature and is not intended to limit the disclosure, its application, or uses. The broad teachings of the present disclosure can be embodied in various forms. Thus, while the present disclosure describes particular examples, other variations will become apparent upon review of the drawings, specifications, and the following claims, and the true scope of the present disclosure is not limited thereto. It should be understood that one or more steps of a method may be performed in a different order (or simultaneously) without altering the principles of the present disclosure. Furthermore, although each embodiment is described above as having particular features, one or more features described with respect to an embodiment of the present disclosure can be implemented in other embodiments and / or in combination with features of other embodiments (even if the combination is not expressly stated). In other words, the described embodiments are not mutually exclusive, and permutations of one or more embodiments with each other remain within the scope of the present disclosure.

[0071] Spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including "connected," "engaged," "coupled," "adjacent," "adjacent," "on," "above," "below," and "disposed." When a relationship between a first element and a second element is described in the above disclosure, unless expressly specified as "direct," the relationship may be a direct relationship where no other intervening elements exist between the first element and the second element, or an indirect relationship where one or more intervening elements (spatial or functional) exist between the first element and the second element. As used herein, the phrase "at least one of A, B, and C" should be interpreted to mean a logical non-exclusive OR (A OR B OR C), and not to mean "at least one of A, at least one of B, and at least one of C."

[0072] In some embodiments, the controller is part of a system, which may be part of the examples above. Such systems may include semiconductor processing equipment, such as processing tools, chambers, processing platforms, and / or specific processing components (e.g., wafer pedestals, gas flow systems). These systems may be integrated with electronics for controlling operations before, during, and after processing of semiconductor wafers or substrates. These electronics may be referred to as a "controller," which may control various components or subcomponents of the system. Depending on the processing requirements and / or type of system, the controller may be programmed to control any process disclosed herein, including supply of process 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 supply settings, position operation settings, wafer transfer to and from the tool and other transfer tools and / or load locks connected or coupled to the specific system.

[0073] A controller may be generally defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. Integrated circuits may include chips in firmware format 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). Program instructions may be instructions communicated to the controller in the form of various personalizations (or program files) that define operational parameters for performing a particular process on or for a semiconductor wafer or for a system. In some embodiments, the operational parameters may be part of a recipe defined by a process engineer to accomplish one or more processing steps in the manufacture of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0074] In some embodiments, the controller may be part of or coupled to a computer integrated with, coupled to, or otherwise networked to the system. For example, the controller may be in the “cloud” that enables remote access to wafer processing, or may be all or part of a fab host computer system. The computer may enable remote access to the system to monitor the progress of manufacturing operations, examine the history of past manufacturing operations, examine trends or performance metrics from multiple manufacturing operations, and modify parameters of a current process, configure processing steps following a current process, or initiate a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the 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 from the remote computer to the system. In some examples, the controller receives instructions in the form of data specifying parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool the controller is configured to connect to or control. Thus, as described above, the controller may be distributed, for example, by including one or more separate controllers networked together and cooperating toward a common purpose, such as the process or control described herein. An example of a controller distributed for such a purpose would be one or more integrated circuits on the chamber that are located remotely (e.g., at the platform level or as part of a remote computer) and communicate with one or more integrated circuits that cooperate to control the process in the chamber.

[0075] Without limitation, example systems may include plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and other semiconductor processing systems related to or usable in the fabrication and / or manufacturing of semiconductor wafers.

[0076] As noted above, depending on the process steps being performed by the tool, the controller may be in communication with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or tools used to transport materials to and from tool locations and / or load ports in a semiconductor fabrication factory to transport wafer containers. The present disclosure includes the following application examples: [Application example 1] a substrate support configured to support a substrate having a diameter D, first and second inner electrodes, each D-shaped and defining a first outer diameter less than D, and configured to be connected to an electrostatic chuck (ESC) voltage to clamp the substrate to the substrate support during processing; an outer electrode including: (i) a ring-shaped outer portion surrounding the first inner electrode and the second inner electrode; and (ii) a central portion passing between the first inner electrode and the second inner electrode and connecting to both sides of an inner diameter of the ring-shaped outer portion; a substrate support, wherein the inner diameter of the ring-shaped outer portion is greater than the diameter D of the substrate such that the inner diameter of the ring-shaped outer portion and an intersection between the inner diameter of the ring-shaped outer portion and the central portion and the ring-shaped outer portion are located radially outside the diameter D of the substrate. [Application example 2] The substrate support according to Application Example 1, further comprising: A substrate support comprising: (i) the first outer diameter defined by the first inner electrode and the second inner electrode; and (ii) a gap defined between the inner diameter of the ring-shaped outer portion. [Application example 3] The substrate support according to Application Example 2, The gap is positioned below and overlaps the outer edge of the substrate. [Application example 4] The substrate support according to Application Example 2, The gap has a width of 2.2 to 7.5 mm. [Application example 5] The substrate support according to Application Example 1, A substrate support, wherein the inner diameter of the ring-shaped outer portion is less than 1.0 mm larger than the diameter D of the substrate. [Application Example 6] The substrate support according to Application Example 1, The inner diameter of the ring-shaped outer portion is 300.4 to 305 mm. [Application Example 7] The substrate support according to Application Example 6, The substrate support, wherein the first outer diameter defined by the first inner electrode and the second inner electrode is 290 to 296 mm. [Application Example 8] The substrate support according to Application Example 1, further comprising: A substrate support comprising a pocket in a first surface of the substrate support configured to hold the substrate. [Application Example 9] The substrate support according to Application Example 8, further comprising: A substrate support comprising the substrate disposed in the pocket. [Application Example 10] The substrate support according to Application Example 8, The substrate support has a pocket diameter of 302 to 310 mm. [Application Example 11] The substrate support according to Application Example 8, The inner diameter of the ring-shaped outer portion overlies the pocket. [Application Example 12] A substrate support configured to support a substrate, first and second inner electrodes, each D-shaped and configured to be connected to an electrostatic chuck (ESC) voltage to clamp the substrate to the substrate support during processing; an outer electrode including: (i) a ring-shaped outer portion surrounding the first inner electrode and the second inner electrode; and (ii) a central portion connecting to either side of an inner diameter of the ring-shaped outer portion; The substrate support, wherein the outer electrode is not coplanar with the first inner electrode and the second inner electrode. [Application Example 13] The substrate support according to Application Example 12, The outer electrode is positioned below the first inner electrode and the second inner electrode. [Application Example 14] The substrate support according to Application Example 12, The substrate support, wherein the central portion comprises a plurality of radial conductors extending outward from the conductive bar to connect to the ring-shaped outer portion. [Application Example 15] The substrate support according to Application Example 14, The substrate support, wherein the plurality of radial conductors includes two or more of the radial conductors. [Application Example 16] The substrate support according to Application Example 14, The substrate support, wherein the plurality of radial conductors includes four or more of the radial conductors. [Application Example 17] A substrate support configured to support a substrate, first and second inner electrodes, each D-shaped and configured to be connected to an electrostatic chuck (ESC) voltage to clamp the substrate to the substrate support during processing; an outer electrode including: (i) a ring-shaped outer portion surrounding the first inner electrode and the second inner electrode; (ii) a central portion located below the ring-shaped outer portion; (iii) a ring surrounding the central portion, coplanar with the central portion, and electrically connected to the central portion; and (iv) at least one vertical portion electrically connecting the ring to the ring-shaped outer portion; A substrate support comprising: [Application Example 18] The substrate support according to Application Example 17, The substrate support, wherein the central portion comprises a plurality of radial conductors extending outward from the conductive bars to connect to the ring. [Application Example 19] The substrate support according to Application Example 18, The substrate support, wherein the plurality of radial conductors includes two or more of the radial conductors. [Application Example 20] The substrate support according to Application Example 18, The substrate support, wherein the plurality of radial conductors includes four or more of the radial conductors.

Claims

1. a substrate support configured to support a substrate having a diameter D, first and second inner electrodes, each D-shaped and defining a first outer diameter less than D, the first and second inner electrodes configured to be connected to an electrostatic chuck (ESC) voltage to clamp the substrate to the substrate support during processing; an outer electrode including: (i) a ring-shaped outer portion surrounding the first inner electrode and the second inner electrode; and (ii) a central portion passing between the first inner electrode and the second inner electrode and connecting to both sides of an inner diameter of the ring-shaped outer portion; a substrate support, wherein the inner diameter of the ring-shaped outer portion is greater than the diameter D of the substrate such that the inner diameter of the ring-shaped outer portion and an intersection between the inner diameter of the ring-shaped outer portion and the central portion and the ring-shaped outer portion are located radially outside the diameter D of the substrate.

2. 10. The substrate support of claim 1, further comprising: A substrate support comprising: (i) the first outer diameter defined by the first inner electrode and the second inner electrode; and (ii) a gap defined between the inner diameter of the ring-shaped outer portion.

3. 3. The substrate support of claim 2, The gap is positioned below and overlaps the outer edge of the substrate.

4. 3. The substrate support of claim 2, The substrate support, wherein the gap has a width of 2.2 to 7.5 mm.

5. 10. The substrate support of claim 1, A substrate support, wherein the inner diameter of the ring-shaped outer portion is less than 1.0 mm larger than the diameter D of the substrate.

6. 10. The substrate support of claim 1, A substrate support, wherein the inner diameter of the ring-shaped outer portion is 300.4 to 305 mm.

7. 7. The substrate support of claim 6, The substrate support, wherein the first outer diameter defined by the first inner electrode and the second inner electrode is 290 to 296 mm.

8. 10. The substrate support of claim 1, further comprising: The substrate support comprises a pocket in a first surface of the substrate support configured to hold the substrate.

9. 9. The substrate support of claim 8, further comprising: A substrate support comprising the substrate disposed in the pocket.

10. 9. The substrate support of claim 8, A substrate support, wherein the pocket has a diameter of 302 to 310 mm.

11. 9. The substrate support of claim 8, The inner diameter of the ring-shaped outer portion overlies the pocket.

12. The substrate support of claim 1, The substrate support, wherein the outer electrode is not coplanar with the first inner electrode and the second inner electrode.

13. 13. The substrate support of claim 12, The outer electrode is positioned below the first inner electrode and the second inner electrode.

14. 13. The substrate support of claim 12, The substrate support, wherein the central portion comprises a plurality of radial conductors extending outward from the conductive bar to connect to the ring-shaped outer portion.

15. 15. The substrate support of claim 14, The substrate support, wherein the plurality of radial conductors includes two or more of the radial conductors.

16. 15. The substrate support of claim 14, The substrate support, wherein the plurality of radial conductors includes four or more of the radial conductors.

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