Electrostatic chuck with top surface pattern for temperature uniformity

Abstract

An electrostatic chuck includes a baseplate and a ceramic plate attached by a bonding layer to the baseplate. The ceramic plate includes a first annular seal band arranged adjacent to a radially outer edge of the ceramic plate; and a second annular seal band arranged radially inwardly from the first annular seal band. The first annular seal band and the second annular seal band define an outer cooling gas zone. A plurality of contact pads is arranged between the first annular seal band and the second annular seal band. A first plurality of cooling gas grooves is arranged between the plurality of contact pads, between first ones of the plurality of contact pads and the first annular seal band, and between second ones of the plurality of contact pads and the second annular seal band.

Description

Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAELECTROSTATIC CHUCK WITH TOP SURFACE PATTERN FOR TEMPERATURE UNIFORMITYCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No.63 / 721 ,044 filed on November 15, 2024. The entire disclosure of the above application is incorporated herein by reference.FIELD

[0002] The present disclosure relates to substrate processing systems, and more particularly to an electrostatic chuck with top surface pattern for temperature uniformity.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] Substrate processing systems may be used to treat substrates such as semiconductor wafers. The substrate treatments may include deposition, etching, cleaning, and / or other treatments. During processing, a substrate is arranged on a substrate support in a processing chamber of the substrate processing system. Gas mixtures are introduced into the processing chamber using a gas delivery device. In some processes, radio frequency (RF) plasma may be used to initiate chemical reactions.SUMMARY

[0005] An electrostatic chuck includes a baseplate and a ceramic plate attached by a bonding layer to the baseplate. The ceramic plate includes a first annular seal band arranged adjacent to a radially outer edge of the ceramic plate; and a second annular seal band arranged radially inwardly from the first annular seal band. The first annular seal band and the second annular seal band define an outer cooling gas zone. A plurality of contact pads is arranged between the first annular seal band and the second annular seal band. A first plurality of cooling gas grooves is at least one of arranged between the plurality of contact pads, arranged between first ones of the plurality of contact pads andAttorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAthe first annular seal band, and arranged between second ones of the plurality of contact pads and the second annular seal band.

[0006] In other features, the plurality of contact pads fill in a range from 20% to 95% of an annular area between a radially inner edge of the first annular seal band and a radially outer edge of the second annular seal band. The plurality of contact pads fill in a range from 60% to 95% of an annular area between the first annular seal band and the second annular seal band. A cooling gas zone is located radially inwardly from the second annular seal band. The cooling gas zone includes a first surface located radially inwardly from the second annular seal band, a plurality of mesas extending upwardly from the first surface, and a second plurality of cooling grooves extending downwardly from the first surface.

[0007] In other features, the first plurality of cooling gas grooves extend downwardly below a plane including the first surface. The first plurality of cooling gas grooves extend downwardly below a plane including a bottom of the second plurality of cooling grooves. The first plurality of cooling gas grooves extend to a plane located above a plane including the first surface. A depth of the first plurality of cooling gas grooves between the plurality of contact pads is in a range from 0.05 pm to 200 pm.

[0008] In other features, the plurality of contact pads have a radial width in a range from 1.0 mm to 8mm, and the plurality of contact pads have a circumferential width in a range from 1.0 mm to 8mm.

[0009] In other features, a width of the first plurality of cooling gas grooves between the plurality of contact pads and between the plurality of contact pads and the first and second annular seal bands is in a range from 0.1 mm to 0.8mm.

[0010] In other features, a width and a depth of the first plurality of cooling gas grooves between the plurality of contact pads and between the plurality of contact pads and the first and second annular seal bands is the same. The first annular seal band and the second annular seal band have a radial width in a range from 0.5 to 3mm. The plurality of contact pads are arranged in T annular rings spaced evenly between the first annular seal band and the second annular seal band, where T is an integer greater than zero. The plurality of contact pads have a shape selected from a group consisting of rectangular, trapezoidal, circular, elliptical, polygonal, and oblong.Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA

[0011] An electrostatic chuck includes a baseplate and a ceramic plate attached by a bonding layer to the baseplate. The ceramic plate includes a first annular seal band arranged adjacent to a radially outer edge of the ceramic plate and a second annular seal band arranged radially inwardly from the first annular seal band. An outer cooling gas zone is defined between the first annular seal band and the second annular seal band. A cooling gas groove is arranged between the first annular seal band and the second annular seal band. G cooling gas outlets are arranged in the cooling gas groove, where G is an integer greater than one.

[0012] In other features, a cooling gas zone located radially inwardly from the second annular seal band. The cooling gas zone includes a first surface located radially inwardly from the second annular seal band, a plurality of mesas extending upwardly from the first surface, and a first plurality of cooling grooves extending downwardly from the first surface.

[0013] In other features, the first plurality of cooling grooves extends downwardly below a plane including the first surface. The cooling gas groove extends downwardly below a plane parallel to a bottom of the first plurality of cooling grooves. The cooling gas groove extends to a plane located above a plane including the first surface.

[0014] In other features, a depth of the cooling gas groove between the first annular seal band and the second annular seal band is in a range from 0.05 pm to 200 pm. A first radial width of the cooling gas groove is in a range from 0.5 mm to 3mm. A second radial width of at least one of the first annular seal band and the second annular seal band is in a range from 1.0 mm to 3mm.

[0015] In other features, the second annular seal band includes G inwardly projecting portions and wherein the G cooling gas outlets are arranged in the G inwardly projecting portions. The G inwardly projecting portions are spaced 360Q / G.

[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 intended for purposes of illustration only and are not intended to limit the scope of the disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA

[0018] FIG. 1 is a functional block diagram of an example of a substrate processing system including an electrostatic chuck according to the present disclosure;

[0019] FIG. 2 is a perspective view of an example of an electrostatic chuck;

[0020] FIG. 3 is a plan view of an example of an electrostatic chuck with a ceramic plate including an outer cooling zone with increased contact area to provide improved temperature uniformity according to the present disclosure;

[0021] FIGS. 4A to 4D are side cross sections showing examples of mesas, seal bands, and cooling gas grooves according to the present disclosure;

[0022] FIG. 5 is a graph showing contact area as a function of radial distance from a center of the ceramic plate according to the present disclosure;

[0023] FIG. 6 is a graph showing substrate temperature as a function of radial distance from a center of the ceramic plate according to the present disclosure;

[0024] FIG. 7 is a plan view of another example of an electrostatic chuck with an outer cooling zone with high contact area to provide improved temperature uniformity according to the present disclosure; and

[0025] FIG. 8 is a plan view of another example of an electrostatic chuck with an outer cooling zone with high contact area to provide improved temperature uniformity according to the present disclosure.

[0026] In the drawings, reference numbers may be reused to identify similar and / or identical elements.DETAILED DESCRIPTION

[0027] During processing, a substate is clamped to an upper surface of a ceramic plate of an electrostatic chuck (ESC). Process gases are supplied and plasma is struck inside of the processing chamber. The substrate is heated by the plasma. The process will typically require the substrate temperature to be maintained within a predetermined temperature range. Maintaining temperature uniformity from a center to an edge of the substrate during plasma processing is difficult. When the temperature of the substrate is not uniform across the substrate during processing, the process may produce different results in different regions of the substrate, which reduces yield.

[0028] Some electrostatic chucks control the substrate temperature during plasma processing use cooling gas zones located below the substrate. The top surface of theAttorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAceramic plate includes concentric annular seal bands and raised features or mesas arranged between the annular seal bands to vary cooling within each zone. The annular seal bands create different cooling gas zones at different radial positions of the substrate. Cooling gas such as helium (He) may be supplied by cooling gas outlets into cooling grooves in the cooling gas zones below the substrate. The pressure of the cooling gas supplied to each zone may also be varied. For example, cooling gas zones located below hotter substrate regions may receive cooling gas at higher pressures than cooling gas zones located below cooler substrate regions.

[0029] In some examples, the cooling gas pressure supplied to the cooling gas zones varies within a predetermined range (e.g., 20 Torr (T) to 80T). For example, cooling gas pressure at a center of the substrate is set to lower values (e.g., 20 to 30T) to provide less cooling due to a lower heat load. Cooling gas pressure is set to a higher values (e.g., 50T to 70T) at a radially outer edge of the substrate to provide additional cooling due to the higher heat load. Using this approach increases cooling near the substrate edge while bringing the average temperature within a desired temperature range. However, using higher cooling gas pressure increases the probability of arcing. Controlling the temperature profile of the radially outer edge of the substrate at lower cooling gas pressures will reduce or prevent arcing between the substrate and the substrate support and provide additional head room for increasing the cooling gas pressure as the tool ages.

[0030] A substrate support according to the present disclosure includes a ceramic plate with a plurality of contact pads located between seal bands in an outermost cooling gas zone. In some examples, radial and / or circumferential widths of the plurality of contact pads are at least 10 times larger than the diameter of the mesas. The seal bands and the plurality of contact pads provide high contact area. The plurality of contact pads are separated by cooling gas grooves. The plurality of contact pads reduce the substrate temperature at the radially outer edge (e.g., without using significantly higher cooling gas pressures). In some examples, the cooling gas pressures, the seal bands, and the plurality of contact pads are selected to flatten the radial substrate temperature distribution using approximately the same cooling gas pressures. In some examples, the cooling gas pressures supplied to the inner cooling gas zones are higher than the cooling gas pressure supplied to the outermost cooling gas zone.Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA

[0031] The substrate processing system provides improved temperature control across the substrate and at the radially outer substrate edge with lower cooling gas pressure and corresponding lower probability of arcing. The improved temperature control increases device yield by increasing the useable surface area of the substrate (since an edge exclusion area is reduced).

[0032] Referring now to FIG. 1, a substrate processing system 100 includes a processing chamber 102 including a gas distribution device 104 and a substrate support 106 such as an electrostatic chuck (ESC). During operation, a substrate 108 is arranged on the substrate support 106. The substrate support 106 includes a baseplate 110. In some examples, the baseplate 110 is made of a conducting material such as aluminum. The baseplate 110 supports a ceramic layer 112. A bond layer 114 is used to bond the ceramic layer 112 to the baseplate 110. The baseplate 110 may include one or more coolant channels 116 for flowing liquid coolant. In some examples, an edge ring 118 is arranged around the substrate support 106 to shape the plasma near a radially outer edge of the substrate.

[0033] A gas delivery system 130 includes one or more gas sources 132-1 , 132-2, ..., and 132-N, where N is an integer. The gas sources 132 supply one or more process gas mixtures. For an etching process, the process gas mixture may include including carrier gas, inert gases, etching gas, etc. For a deposition process, the process gas mixture may include including carrier gas, inert gases, deposition precursor gases, etc. The gas sources 132 are connected by flow metering devices 134-1 , 134-2, ..., and 134-N (e.g., mass flow controllers and valves) to a manifold 140. An output of the manifold 140 is fed to the gas distribution device 104.

[0034] In some examples, a vapor delivery system 170 includes one or more vapor delivery sources that supply vapor to the manifold 140 or connect to the gas distribution device 104 downstream from the manifold 140. In some examples, the vapor delivery system 170 includes one or more ampoules 174, vaporizers 176, and flow metering devices 178 to controllably supply the vapor to the processing chamber.

[0035] In some examples, a temperature controller 142 is connected to heating elements 144 (e.g., thermal control elements (TCEs) or resistive heaters) arranged in the ceramic layer 112. The temperature controller 142 may be used to supply power to the heating elements 144 to control a temperature of the substrate support 106 and the substrate 108 during processing. The temperature controller 142 also operates a coolantAttorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAassembly 146 that controls coolant flow through the coolant channels 116. For example, the coolant assembly 146 may include a coolant pump and coolant reservoir (not shown). The temperature controller 142 operates the coolant assembly 146 to selectively flow the coolant through the coolant channels 116 to cool the substrate support 106.

[0036] A valve 150 and a pump 152 are used to control pressure within the processing chamber 102 and / or to evacuate reactants from the processing chamber 102. A gas source 151 and a flow controller 153 can be used to supply cooling gas such as helium or other gas between the substrate 108 and a top surface of the ceramic layer 112. As will be described further below, the top surface of the ceramic layer 112 below the substrate includes annular seal bands, mesas, cooling gas grooves, and cooling gas outlets to supply cooling gas to the cooling grooves.

[0037] A plasma generator 154 includes a radio frequency (RF) source 156 to output RF voltage / power to a matching network 158. The matching network 158 matches the impedance of the RF source 156 to the impedance of the load including the processing chamber and plasma.

[0038] A controller 160 may be used to monitor system parameters and to control components of the substrate processing system 100 based on a recipe. One or more robots 161 may be used to deliver substrates onto, and remove substrates from, the substrate support 106. The gas distribution device 104 includes a gas plenum 191 that distributes gas from the gas delivery system 130 or vapor from the vapor delivery system 170 to gas through holes passing through an electrode 193 that is grounded.

[0039] Referring now to FIG. 2, a substrate support 200 such as an electrostatic chuck is shown to include a ceramic plate 210 attached by a bonding layer (not shown) to a baseplate 214. The ceramic plate 210 includes N annular seal bands 216-1 , 216-2, ..., and 216-N (collectively N annular seal bands 216) that are arranged concentrically on a surface 220 of the ceramic plate 210, where N is an integer greater than one. The N annular seal bands 216 project upwardly from the surface 220 by a predetermined distance.

[0040] Areas between the N annular seal bands 216 define cooling gas zones 218-1 , 218-2, ..., and 218-M (collectively cooling gas zones 218), where M is an integer greater than one. In some examples, M = N+1. Some or all of the cooling gas zones 218 include a plurality of mesas 224 extending upwardly from the surface 220. The plurality of mesas 224 are typically arranged in concentric circles, although other patterns can be used. InAttorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAsome examples, the plurality of mesas 224 typically have a circular shape. Some or all of the cooling gas zones include cooling gas grooves 226 extending below the surface 220 and cooling gas outlets 228 to supply cooling gas to the cooling gas zones.

[0041] Three or more lift pin holes 230 allow lift pins to be raised to receive a substrate delivered to the processing chamber and to lower or raise the substrate relative to the ceramic plate 210 before or after processing. In some examples, multiple sets of cooling gas grooves 226 are spaced circumferentially around the ceramic plate 210 in each of the cooling gas zones 218. In some examples, each of the sets of the cooling gas grooves 226 includes one or more radial segments and one or more arcuate segments. In some examples, the cooling gas outlets 228 are located at intersections of the radial and arcuate segments.

[0042] During substrate processing, the substrate is arranged on a top surface of the ceramic plate 210. The substrate is supported by the N annular seal bands 216 and the mesas 224. Cooling gas is supplied by one or more of the cooling gas outlets 228 to the cooling gas grooves 226 in the cooling gas zones 218. The cooling gas exchanges heat with a bottom surface of the substrate and exposed side surfaces of the N annular seal bands 216 and the mesas 224. The contact area between the seal bands and the mesas 224 and the substrate and the cooling gas pressure can also be used to control the temperature in corresponding zones of the substrate.

[0043] An edge of the substrate typically extends over the radially outer edge of the outer annular seal band. In other words, an annular band at the radially outer edge of the substrate is not in direct contact with the ceramic plate and the temperature is generally hotter than other cooled substrate locations, which leads to substrate non-uniformity at or near those locations. As a result, these areas of the substate may need to be scrapped, which is inefficient.

[0044] The substrate support according to the present disclosure provides additional cooling at the radially outer edge to offset the higher heat load at these locations. Referring now to FIG. 3, a substrate support 300 such as an electrostatic chuck according to the present disclosure is shown. The substrate support 300 includes a ceramic plate 310 attached by a bonding layer to a baseplate 314. A surface 320 of the ceramic plate 310 includes N annular seal bands 316-1 , 316-2, ..., and 316-N (collectively N annular seal bands 316) that are arranged concentrically, where N is an integer greater than one.Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAThe N annular seal bands 316 include radially inner and outer annular side walls and an annular planar upper surface against which the substrate is clamped.

[0045] The N annular seal bands 316 define M cooling gas zones 318-1 , 318-2, and 318-M (collectively M cooling gas zones 318), where M is an integer greater than one. In some examples, M=N-1 , M=N, or M = N+1. The N annular seal bands 316 are arranged concentrically and project upwardly from the surface 320 by a predetermined distance. A radial width of the N annular seal bands 316 may be the same or different and facing edges of adjacent ones of the N annular seal bands 316 may be spaced by the same radial distance or different radial distances.

[0046] In some examples, the N annular seal bands 316 include an outer annular seal band, a mid-outer annular seal band, a mid-inner annular seal band, and an inner annular seal band (although additional or fewer seal bands 316 can be used). In other examples, the N annular seal bands 316 include at least two annular seal bands (corresponding to the annular seal bands 316-1 and 316-2).

[0047] One or more inner ones of the M cooling gas zones 318 include a pattern of mesas 324, cooling gas grooves 326, and cooling gas outlets 328 to supply cooling gas to the cooling gas grooves 326. The cooling gas grooves 326 extend below a plane including the surface 320. The mesas 324 extend a predetermined distance above the surface 320.

[0048] As described above, cooling gas grooves, mesas, and cooling gas outlets are arranged circumferentially around the ceramic plate 310 in one or more of the M cooling gas zones 318. In some examples, each of the sets of the cooling gas grooves 326 includes one or more radial segments and / or one or more circumferential segments. In some examples, the cooling gas grooves 326 are located at intersections of the radial and circumferential segments, although other locations can be used.

[0049] In some examples, a radial distance between a radially inner edge of the annular seal band 316-1 and a radially outer edge of the annular seal band 316-2 is reduced relative to the other cooling gas zones. A plurality of contact pads 340 are arranged between the annular seal band 316-1 and the annular seal band 316-2. In some examples, the plurality of contact pads 340 have a radial width that is significantly larger (e.g., 5x, 10x or higher) than the radial width of the mesas 324. In some examples, the plurality of contact pads are arranged in T annular rings, where T is an integer greater than zero (e.g., 1 , 2, 3 or more). In some examples, the N annular seal bands 316, theAttorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAmesas 324, and / or the plurality of contact pads 340 extend above the surface 320 by the same predetermined distance to allow upper planar surfaces thereof to contact a bottom surface of the substrate.

[0050] In some examples, the plurality of contact pads 340 have a rectangular, trapezoidal, circular, elliptical, polygonal, oblong, or other suitable shape. In some examples, the plurality of contact pads 340 are arranged symmetrically in an annular band in the cooling gas zone 318-1. In some examples, the plurality of contact pads 340 are arranged into one or more concentric rings positioned in the cooling gas zone 318-1 between the annular seal band 316-1 and the annular seal band 316-2. Radial and circumferentially oriented cooling gas grooves 342 are arranged between the plurality of contact pads 340 and the seal bands 316-1 and 316-2.

[0051] The shapes and areas of the plurality of contact pads 340 and widths and depths of the cooling gas grooves 342 (e.g., located between the plurality of contact pads 340 and between the plurality of contact pads 340 and the annular seal bands 316-1 and 316-2) are selected to ensure quick and efficient penetration of the cooling gas between the contact pads 340 and the substrate for optimal thermal transfer.

[0052] In FIGS. 4A to 4D, example variations of the plurality of contact pads 340, the cooling gas grooves 342, the N annular seal bands 316, and the mesas 324 are shown relative to a bottom surface 317 of a substrate 319. In FIG. 4A, a vertical distance d1 is defined between the bottom surface 317 of the substrate 319 and the bottom surface of the cooling gas grooves 342 in the cooling zone 318-1.

[0053] A vertical distance d2 is defined between the bottom surface 317 of the substrate 319 and the surface 320 located between the mesas 324. A bottom surface in the cooling gas grooves 326 located between the mesas 324 defines a vertical distance d3 relative to the bottom surface 317 of the substrate 319. The cooling gas grooves 326 between the mesas 324 extend below the surface 320 (e.g., d3 > d2).

[0054] In some examples, the seal bands 316-1 and 316-2 (and / or others of the N annular seal bands 316) have a radial width w1. However, the seal bands 316-1 and 316-2 can have different radial widths). The plurality of contact pads 340 have a radial width w2. The mesas 324 have a radial width w3. In some examples, the radial width w3 of the mesas 324 is less than the radial width w1 of the N annular seal bands 316. In some examples, the radial width w3 of the mesas 324 is less than the radial width w2 of the plurality of contact pads 340.Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA

[0055] In FIG. 4A, the cooling gas grooves 342 between the plurality of contact pads 340 extend downwardly to a plane parallel to the surface 320. In other words, the distances d1 and d2 are the same and the distance d3 is greater than d1 and d2.

[0056] In FIG. 4B, the cooling gas grooves 342 between the plurality of contact pads 340 extend downwardly below a plane parallel to the surface 320. In other words, the distance d1 is greater than d2. In this example, the distance d1 is equal to the distance d3.

[0057] In FIG. 4G, the cooling gas grooves 342 extend downwardly below a plane including a bottom surface of the cooling gas grooves 326. In other words, the distance d1 is greater than the distance d3 and the distance d2 is less than d1 and d3.

[0058] In FIG. 4D, the cooling gas grooves 342 extend downwardly to a plane above the surface 320. In other words, the distance d1 is less than the distance d2 and the distance d3 is greater than the distance d2. As can be appreciated, the cooling gas grooves 342 can extend to other distances between and / or outside of those depicted in FIGS. 4A to 4D.

[0059] In some examples, di is in a range from 4 pm to 30 pm. In some examples, di is in a range from 4 pm to 15 pm (e.g., 10 pm). In some examples, cfc is in a range from 4 pm to 100 pm. In some examples, cfe is in a range from 0 pm to 150 pm.

[0060] In some examples, the depth of the cooling gas grooves 342 (distance d1) between the plurality of contact pads 340 is in a range from 0.05 pm to 200 pm below the bottom surface 317 of the substrate 319. In some examples, the radial width w2 (and / or the circumferential width) of the plurality of contact pads 340 is in a range from 1.0 mm to 8mm. In some examples, the radial width w4 (FIG. 4B) of the cooling gas grooves 342 between the plurality of contact pads 340 and / or between the plurality of contact pads 340 and the annular seal bands 216-1 and 316-2 is in a range from 0.1 mm to 0.8mm.

[0061] In some examples, the top surfaces of the plurality of contact pads 340 comprise 20% to 95% of the annular area located between a radially inner edge of the annular seal band 316-1 and a radially outer edge of the annular seal band 316-2. In some examples, the top surfaces of the plurality of contact pads 340 comprise 40% to 90%, 60% to 90%, or 80% to 90% of the annular area located between a radially inner edge of the annular seal band 316-1 and a radially outer edge of the annular seal band 316-2. In some examples, the top surfaces of the plurality of contact pads 340 comprise 20% to 35%,Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA35% to 50%, or 50% to 65% of the annular area located between a radially inner edge of the annular seal band 316-1 and a radially outer edge of the annular seal band 316-2. In some examples, the top surfaces of the plurality of contact pads 340 comprise 60% to 95% of the annular area between a radially inner edge of the annular seal band 316-1 and a radially outer edge of the annular seal band 316-2. In some examples, the top surfaces of the plurality of contact pads 340 comprise 80% to 95% of the annular area between a radially inner edge of the annular seal band 316-1 and a radially outer edge of the annular seal band 316-2. In some examples, the radial width w1 of the annular seal bands 316-1 and 316-2 is in a range from 0.5 mm to 3 mm.

[0062] Referring now to FIG. 5, a substrate contact area percentage (%) is shown as a function of radius from a center of the ceramic plate in the different cooling gas zones. Since the mesas in the cooling gas zones are typically arranged in circular bands that are spaced radially within the respective cooling gas zone, the contact areas for each zone are calculated as discrete units and therefore increase in discrete steps. In some examples, the contact area % increases monotonically from a center cooling gas zone to the outermost cooling gas zone. Varying the cooling gas in each cooling gas zone provides additional control of the temperature profile. However, a lower differential pressure is required due to the increased cooling provided in the outermost cooling zone.

[0063] Referring now to FIG. 6, a temperature of the substrate is shown as a function of radius from a center of the ceramic plate. In some examples, the temperature is constant from a center of the ceramic plate to the edge of the ceramic plate. As can be appreciated, there may be a slight dip in the temperature of the substate in the outer cooling gas zone. In some examples, the temperature dip is less than 1.0QC. In some examples, the temperature dip is less than 0.5QC.

[0064] Referring now to FIG. 7, another substrate support with increased cooling capacity near the radially outer edge of the substrate is shown. No contact pads or mesas are arranged in an annular area between the seal bands of the outermost cooling gas zone. In other words, the annular area between the seal bands of the outermost cooling gas zone acts as a cooling gas groove. A radial distance between the seal bands around the outermost cooling gas zone is significantly decreased to further shift most of the contact area of the seal bands toward the radially outer edge of the substrate.

[0065] In FIG. 7, a substrate support 400 includes a ceramic plate 410 attached by a bonding layer to a baseplate 414. The ceramic plate 410 includes N annular seal bandsAttorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA416-1 , 416-2, ..., and 416-N (collectively N annular seal bands 416) that are arranged concentrically, where N is an integer greater than one. The N annular seal bands 416 include radially inner and outer annular side walls and an annular planar upper surface against which the substrate is clamped. The N annular seal bands 416 define cooling gas zones 418-1 , 418-2, ..., and 418-M (collectively cooling gas zones 418), where M is an integer greater than one. In some examples, M = N-1 , M = N, or M = N+1. The N annular seal bands 416 project upwardly from a surface 420 by a predetermined distance. The N annular seal bands 416 have the same or different radial widths.

[0066] One or more inner ones of the cooling gas zones 418 include a pattern of mesas 424, cooling gas grooves 426, and cooling gas outlets 428 to supply cooling gas. The cooling gas grooves 426 in the inner cooling gas zones 418-2 to 418-N extend downwardly below the surface 420. The mesas 424 extend above the surface 420. In some examples, the N annular seal bands 416 and the mesas 424 extend above the surface 420 by the same predetermined distance. In some examples, multiple interconnected sets of cooling gas grooves 426 are spaced around the ceramic plate 410 in each of the cooling gas zones 418. In some examples, each of the sets of the cooling gas grooves 426 includes one or more radial segments and / or one or more circumferential segments. In some examples, each of the sets of the cooling gas grooves 426 includes at least one of the cooling gas outlets 428. In some examples, the cooling gas outlets 428 are located along one or more of the cooling gas grooves 426 and / or at intersections of the radial and circumferential segments of the cooling gas grooves 426.

[0067] A cooling gas groove 442 is arranged in the outermost cooling gas zone between the annular seal band 416-1 (outer annular seal band) and the annular seal band 416-2 (mid-outer annular seal band). G cooling gas outlets 444 are arranged along the cooling gas groove 442, where G is an integer greater than one. In some examples, G is in a range from 10 to 30, although additional or fewer can be used. In some examples, the G cooling gas outlets 444 are spaced 360Q / G. In some examples, the cooling gas groove 442 extends downwardly below a plane including the surface 420 (e.g., above or below a plane including bottoms of the cooling gas grooves 426). In some examples, the cooling gas groove 442 extends downwardly to the plane including the surface 420. In some examples, the cooling gas groove 442 extends downwardly to a plane above the surface 420.Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA

[0068] In some examples, the annular seal bands 416-1 and 416-2 have a radial width in a range from 0.5 mm to 3 mm. In some examples, a radial width of the cooling gas groove 442 between the annular seal bands 416-1 and 416-2 is in a range from 0.5 mm to 3mm. In some examples, a depth of the cooling gas grooves 442 between the annular seal bands 416-1 and 416-2 is in a range from 0.5 pm to 200 pm. In some examples, a depth of the cooling gas grooves 442 between the annular seal bands 416-1 and 416-2 is in a range from 5 pm to 100 pm.

[0069] In some examples, a depth of the surface 420 between the inner annular seal bands 416-2 and 416-N is in a range from 5 pm to 150 pm. In some examples, a depth of the surface 420 between the inner annular seal bands 416-2 and 416-N is in a range from 20 pm to 100 pm. In some examples, a depth of the surface 420 between the inner annular seal bands 416-2 and 416-N is in a range from 60 pm to 90 pm.

[0070] Referring now to FIG. 8, locating the cooling gas outlets close to the radially outer edge of the ceramic plate may present manufacturing and / or durability issues. For example, if the cooling gas outlets are arranged too close to the radially outer edge of the ceramic plate, delamination between the ceramic plate and the baseplate may occur. The cooling gas outlets may decrease the strength of the bond between the ceramic plate and the baseplate. In the example in FIG. 8, the outermost cooling gas zone is defined between an outermost seal band and an adjacent annular seal band that includes inwardly projecting to enable location of the cooling gas outlets at a more radially inward location. The outermost seal band and the adjacent annular seal band are spaced closely together (e.g., as described in FIG. 7). The cooling gas outlets are arranged in the inwardly projecting portions. Moving the cooling gas outlets radially inwardly relative to the radially outer edge of the substrate to improve the bonding strength between the ceramic plate and the baseplate.

[0071] In FIG. 8, the substrate support 500 includes a ceramic plate 510 attached by a bonding layer to a baseplate 514. The ceramic plate 510 includes N annular seal bands 516-1 , 516-2, ..., and 516-N (collectively N annular seal bands 516) that are arranged concentrically, where N is an integer greater than one. The N annular seal bands 516 include radially inner and outer annular side walls and an annular planar upper surface against which the substrate is clamped.

[0072] The N annular seal bands 516 define cooling gas zones 518-1 , 518-2, ..., and 518-M (collectively cooling gas zones 518), where M is an integer greater than one. InAttorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAsome examples, M=N-1 , M=N, or M = N+1. The N annular seal bands 516 project upwardly from a surface 520 by a predetermined distance. The N annular seal bands 516 have the same or different radial widths.

[0073] Some or all of the inner cooling gas zones 518-2 to 518-N include a pattern of mesas 524, cooling gas grooves 526, and cooling gas outlets 528 to supply cooling gas. The cooling gas grooves 526 extend below the surface 520. The mesas 524 extend above the surface 520. In some examples, the N annular seal bands 516 and the mesas 524 extend above the surface 520 by the same predetermined distance. In some examples, multiple sets of cooling gas grooves are spaced circumferentially around the ceramic plate 510 in each of the cooling gas zones 518. In some examples, each of the sets of the cooling gas grooves 526 includes one or more radial segments and / or one or more circumferential segments. In some examples, the cooling gas outlets 528 are located at intersections of the radial and circumferential segments.

[0074] A cooling gas groove 542 is arranged between the annular seal band 516-1 (outer annular seal band) and the annular seal band 516-2 (mid-outer annular seal band). The annular seal band 516-1 has an annular shape. The annular seal band 516-2 includes a modified annular shape with G inwardly projecting portions 548, where G is an integer greater than one. In some examples, the G inwardly projecting portions 548 of the seal band 516-2 are spaced uniformly around a periphery of the annular seal band 516-2. In some examples, G is in a range from 10 to 30 and the G cooling gas outlets 544 are spaced 360Q / G. In some examples, the G inwardly projecting portions 548 have an arcuate, elliptical, or semi-circular shape, although other shapes can be used.

[0075] The cooling gas groove 542 includes additional area defined by the G inwardly projecting portions 548. G cooling gas outlets 544 are arranged in the additional area of the G inwardly projecting portions 548 of the seal band 516-2. Moving the cooling gas outlets radially inwardly improves the bonding strength between the ceramic plate and the baseplate.

[0076] The foregoing description is merely illustrative in nature and is in no way 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. It should be understood that one or more steps within a method mayAttorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAbe executed in different order (or concurrently) without altering the principles of the present disclosure. Further, although each of the embodiments is described above as having certain features, any one or more of those features described with respect to any embodiment of the disclosure can be implemented in and / or combined with features of any of the other embodiments, even if that combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and permutations of one or more embodiments with one another remain within the scope of this disclosure.

[0077] 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 and second 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.”

[0078] 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 wafer pedestal, 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. 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.Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA

[0079] 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). 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 embodiments, 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.

[0080] 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. 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. 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 inAttorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POAcommunication 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.

[0081] 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 systems that may be associated or used in the fabrication and / or manufacturing of semiconductor wafers.

[0082] 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. 11804-1 WOHDP Ref. No. 15545-001293-WO-POACLAIMSWhat is claimed is:

1. An electrostatic chuck, comprising:a baseplate; anda ceramic plate attached by a bonding layer to the baseplate including:a first annular seal band arranged adjacent to a radially outer edge of the ceramic plate;a second annular seal band arranged radially inwardly from the first annular seal band,wherein the first annular seal band and the second annular seal band define an outer cooling gas zone;a plurality of contact pads arranged between the first annular seal band and the second annular seal band; anda first plurality of cooling gas grooves arranged:between the plurality of contact pads;between first ones of the plurality of contact pads and the first annular seal band; andbetween second ones of the plurality of contact pads and the second annular seal band.

2. The electrostatic chuck of claim 1 , wherein the plurality of contact pads fill in a range from 20% to 95% of an annular area between a radially inner edge of the first annular seal band and a radially outer edge of the second annular seal band.

3. The electrostatic chuck of claim 1 , wherein the plurality of contact pads fill in a range from 60% to 95% of the annular area between the first annular seal band and the second annular seal band.

4. The electrostatic chuck of claim 1 , further comprising a cooling gas zone located radially inwardly from the second annular seal band including:a first surface located radially inwardly from the second annular seal band; a plurality of mesas extending upwardly from the first surface; anda second plurality of cooling grooves extending downwardly from the first surface.Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA5. The electrostatic chuck of claim 4, wherein the first plurality of cooling gas grooves extend downwardly below a plane including the first surface.

6. The electrostatic chuck of claim 4, wherein the first plurality of cooling gas grooves extend downwardly below a plane including a bottom of the second plurality of cooling grooves.

7. The electrostatic chuck of claim 4, wherein the first plurality of cooling gas grooves extend to a plane located above a plane including the first surface.

8. The electrostatic chuck of claim 1 , wherein a depth of the first plurality of cooling gas grooves between the plurality of contact pads is in a range from 0.05 pm to 200 pm.

9. The electrostatic chuck of claim 1 , wherein:the plurality of contact pads have a radial width in a range from 1.0 mm to 8mm, andthe plurality of contact pads have a circumferential width in a range from 1.0 mm to 8mm.

10. The electrostatic chuck of claim 9, wherein a width of the first plurality of cooling gas grooves between the plurality of contact pads and between the plurality of contact pads and the first and second annular seal bands is in a range from 0.1 mm to 0.8mm.

11. The electrostatic chuck of claim 1 , wherein a width and a depth of the first plurality of cooling gas grooves between the plurality of contact pads and between the plurality of contact pads and the first and second annular seal bands is the same.

12. The electrostatic chuck of claim 1 , wherein the first annular seal band and the second annular seal band have a radial width in a range from 0.5 to 3mm.

13. The electrostatic chuck of claim 1 , wherein the plurality of contact pads are arranged in T annular rings spaced evenly between the first annular seal band and the second annular seal band, where T is an integer greater than zero.Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA14. The electrostatic chuck of claim 1 wherein the plurality of contact pads have a shape selected from a group consisting of rectangular, trapezoidal, circular, elliptical, polygonal, and oblong.

15. An electrostatic chuck, comprising:a baseplate; anda ceramic plate attached by a bonding layer to the baseplate including:a first annular seal band arranged adjacent to a radially outer edge of the ceramic plate;a second annular seal band arranged radially inwardly from the first annular seal band,wherein an outer cooling gas zone is defined between the first annular seal band and the second annular seal band;a cooling gas groove arranged between the first annular seal band and the second annular seal band; andG cooling gas outlets arranged in the cooling gas groove, where G is an integer greater than one.

16. The electrostatic chuck of claim 15, further comprising a cooling gas zone located radially inwardly from the second annular seal band including:a first surface located radially inwardly from the second annular seal band;a plurality of mesas extending upwardly from the first surface; anda first plurality of cooling grooves extending downwardly from the first surface.

17. The electrostatic chuck of claim 16, wherein the first plurality of cooling grooves extends downwardly below a plane including the first surface.

18. The electrostatic chuck of claim 16, wherein the cooling gas groove extends downwardly below a plane parallel to a bottom of the first plurality of cooling grooves.

19. The electrostatic chuck of claim 16, wherein the cooling gas groove extends to a plane located above a plane including the first surface.Attorney Docket No. 11804-1 WOHDP Ref. No. 15545-001293-WO-POA20. The electrostatic chuck of claim 15, wherein a depth of the cooling gas groove between the first annular seal band and the second annular seal band is in a range from 0.05 pm to 200 pm.

21. The electrostatic chuck of claim 15, wherein a first radial width of the cooling gas groove is in a range from 0.5 mm to 3mm.

22. The electrostatic chuck of claim 15, wherein a second radial width of at least one of the first annular seal band and the second annular seal band is in a range from 1.0 mm to 3mm.

23. The electrostatic chuck of claim 15, wherein the second annular seal band includes G inwardly projecting portions and wherein the G cooling gas outlets are arranged in the G inwardly projecting portions.

24. The electrostatic chuck of claim 23, wherein the G inwardly projecting portions are spaced 360Q / G.

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