Semiconductor substrate support with improved high temperature adsorption

Abstract

An exemplary support assembly can include an electrostatic chuck body defining a substrate support surface. The assembly can include a support stem coupled with the electrostatic chuck body. The assembly can include a heater embedded within the electrostatic chuck body. The assembly can also include an electrode embedded within the electrostatic chuck body between the heater and the substrate support surface. The substrate support assembly can be characterized by a leakage current of less than 4 mA or about 4 mA through the electrostatic chuck body at a temperature greater than 500 °C or about 500 °C and at a voltage greater than 600 V or about 600 V.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 879,696, filed July 29, 2019, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] This technology relates to components and equipment used in semiconductor manufacturing. More specifically, this technology relates to substrate support assemblies and other semiconductor processing equipment. Background Technology

[0004] Integrated circuits are made possible through processes that create intricately patterned material layers on a substrate surface. Creating patterned materials on the substrate requires controlled methods for material formation and removal. The temperatures during these processes can directly affect the final product. Substrate temperatures are typically controlled and maintained during processing using components that support the substrate. Internal heating devices can generate heat within the support, and this heat can be conducted to the substrate. Substrate supports can also be used in some technologies to develop substrate-level plasma. Plasma generated near the substrate can cause component bombardment and the formation of parasitic plasma in unfavorable areas of the chamber. Furthermore, using the substrate for both heat generation and plasma generation can introduce interference effects.

[0005] Because various processing techniques utilize elevated temperatures and the formation of substrate-level plasmas, the constituent materials of the substrate support may be exposed to temperatures that affect the electrical operation of the component. Therefore, there is a need for improved systems and methods for producing high-quality devices and structures. These and other needs are addressed by this technology. Summary of the Invention

[0006] An exemplary support assembly may include an electrostatic chuck body defining a substrate support surface. The assembly may include a support rod coupled to the electrostatic chuck body. The assembly may include a heater embedded within the electrostatic chuck body. The assembly may also include electrodes embedded within the electrostatic chuck body between the heater and the substrate support surface. The substrate support assembly may be characterized by a leakage current of less than 4 mA or about 4 mA through the electrostatic chuck body at a temperature greater than or about 500°C and a voltage greater than or about 600V.

[0007] In some embodiments, the substrate support surface can define a recessed ledge extending radially inward from an outer radial edge of the pocket. The electrostatic chuck body can define a plurality of protrusions extending from the substrate support surface within the pocket. A distance between a radially outermost protrusion and an inner radial edge of the recessed ledge can be maintained at less than 3 mm or about 3 mm. The electrostatic chuck body can define more than or about 500 protrusions, and each of the plurality of protrusions can be characterized by a diameter greater than 1 mm or about 1 mm. A subset of the protrusions of the plurality of protrusions can be characterized by a diameter greater than 2 mm or about 2 mm. The plurality of protrusions can define a contact area for a substrate positioned on the substrate support surface of the electrostatic chuck body, and the contact area can be less than or about 10% of a planar area of the substrate. The electrostatic chuck body can comprise a ceramic material. The ceramic material can be or include aluminum nitride. The ceramic material can be characterized by a volume resistivity greater than or about 1 x 1010ohm-cm at a temperature greater than or about 550 °C. 9 ohm-cm or about 1 x 1010ohm-cm at a temperature greater than or about 550 °C. 9 ohm-cm or about 1 x 1010ohm-cm at a temperature greater than or about 550 °C.

[0008] Some embodiments of the present technology can include a substrate support assembly. The substrate support assembly can include an electrostatic chuck body defining a substrate support surface. The assembly can include a heater embedded within the electrostatic chuck body. The assembly can include an electrode embedded within the electrostatic chuck body between the heater and the substrate support surface. The electrode maintains a distance of at least about 3 mm from the substrate support surface within the electrostatic chuck body. The substrate support assembly can be characterized by a leakage current of less than or about 4 mA through the electrostatic chuck body at a temperature greater than or about 540 °C and at a voltage greater than or about 660 V.

[0009] In some embodiments, the electrode can be positioned within the electrostatic chuck body at a depth of at least about 5 mm from the substrate support surface of the electrostatic chuck body. The electrostatic chuck body can include a ceramic material characterized by a volume resistivity greater than or about 1 x 1010ohm-cm at a temperature greater than or about 600 °C. 9 ohm-cm or about 1 x 1010ohm-cm at a temperature greater than or about 550 °C. 9An ohm-cm volume resistivity can characterize the electrostatic chuck body. The electrostatic chuck body can define a pocket within the substrate support surface configured to receive a substrate for processing. The substrate support surface can define a recessed ledge extending radially inward from an outer radial edge of the pocket. The electrostatic chuck body can define a plurality of protrusions extending from the substrate support surface within the pocket. The plurality of protrusions can define a contact area for a substrate positioned on the substrate support surface of the electrostatic chuck body. The contact area can be less than or about 5% of a planar area of the substrate. The substrate support assembly can be characterized by a leakage current of less than or about 4 mA through the electrostatic chuck body at a temperature greater than or about 600 °C and at a voltage greater than or about 800 V.

[0010] Some embodiments of the technology can include a substrate support assembly. The assembly can include an electrostatic chuck body defining a substrate support surface. The assembly can include a support stem coupled with the electrostatic chuck body. The assembly can include a heater embedded within the electrostatic chuck body. The assembly can include an electrode embedded within the electrostatic chuck body between the heater and the substrate support surface. The electrode can maintain a distance of at least about 5 mm from the substrate support surface within the electrostatic chuck body. The substrate support assembly can be characterized by a leakage current of less than or about 4 mA through the electrostatic chuck body at a temperature greater than or about 550 °C and at a voltage greater than or about 650 V.

[0011] Such technology can provide numerous benefits over conventional systems and techniques. For example, embodiments of the technology can provide a substrate support that can facilitate both substrate-level plasma and sustainability during high-temperature operations. Additionally, by providing a reduced leakage current relative to conventional techniques, an increased voltage attraction window can be provided. These and other embodiments, along with many of their advantages and features, are described in more detail in conjunction with the following description and attached figures. BRIEF DESCRIPTION OF DRAWINGS

[0012] The nature and advantages of the disclosed technology can be further understood by reference to the remaining portions of the specification and the attached drawings.

[0013] Figure 1 A top plan view of an exemplary processing system is shown, in accordance with some embodiments of the technology.

[0014] Figure 2 A schematic cross-sectional view of an exemplary plasma system is shown, in accordance with some embodiments of the technology.

[0015] Figure 3 A schematic partial cross-sectional view of an exemplary substrate support assembly is shown, in accordance with some embodiments of the technology.

[0016] Figure 4A schematic partial cross-sectional view of an exemplary substrate support assembly according to some embodiments of the present technology is shown.

[0017] Figure 5 A schematic partial top plan view of an exemplary substrate support assembly according to some embodiments of the present technology is shown.

[0018] Several of the drawings are included as schematic illustrations. It should be understood that the drawings are merely schematic and are not drawn to scale unless otherwise specifically noted. Additionally, as is common in the art, the drawings included herein are not to scale unless specifically noted. Furthermore, the drawings can schematically depict the logical operations of a representative process. In other words, the logical operations necessary for understanding the present technology can be represented as a sequence of interrelated operations. It will be recognized, however, that the various operations disclosed herein can be executed at different times and in different sequences from that shown in the example figures. Additionally, certain operations can be performed concurrently. Accordingly, the drawings and descriptions are to be regarded as illustrative in nature and explanations used are often broken into multiple steps and / or blocks for ease of explanation.

[0019] In the drawings, like reference numerals can be used to denote similar components throughout the several views. Further, various components of the same type can be distinguished by following the designation with a letter that distinguishes among the similar components. If only the first designation is used in the text, the discussion is applicable to any of the similar components having the same first designation irrespective of the letter. DETAILED DESCRIPTION

[0020] Plasma enhanced deposition processes can excite one or more constituent precursors to facilitate film formation on a substrate. These formed films can be generated under conditions that induce stress on the substrate. For example, in the growth of dielectric layers for vertical memory applications, such as ON stack, a number of material layers can be deposited on the substrate. These resulting films can be characterized by internal stress acting on the substrate. This can cause the substrate to bow during processing, which can result in poor uniformity of formation, as well as device damage or failure.

[0021] Electrostatic chucks can be used to create a clamping effect on the substrate to overcome the bowing stress. However, as the number of layers of these device stacks increases, the stress acting on the substrate increases, which can require a proportional increase in the chucking voltage. Additionally, many of these films can be grown at higher temperatures, which further impacts the components of the chamber. For example, some deposition activities can occur at temperatures higher than 500 °C or higher, which can impact the resistivity of the materials of the chamber components, such as the electrostatic chuck. As the resistivity of the materials decreases, current leakage can increase. When combined with the increased voltage used to overcome the increased bowing stress applied to the substrate as the number of deposited layers increases, arcing can occur, which can damage the substrate and chamber components. These issues have limited conventional technology to a narrow chucking window that cannot accommodate increased layer scaling during deposition.

[0022] The present technology overcomes these challenges by having a substrate support assembly with particular materials and configurations that exhibit particular electrical characteristics that can result in reduced leakage current, particularly at elevated temperatures, as compared to conventional technology. Additionally, the assembly can include surface topography that can assist in clamping substrates having stresses corresponding to increasing deposited layers.

[0023] While the remainder of the disclosure will routinely utilize the disclosed technology to identify particular deposition processes, it will be readily understood that the systems and methods are equally applicable to other deposition and cleaning chambers and processes that can occur in the chambers. Thus, the technology should not be considered limited to use with these particular deposition processes or chambers. The disclosure will discuss one possible system and chamber that can include a susceptor according to embodiments of the present technology, and then describe additional variations and adjustments to this system according to embodiments of the present technology.

[0024] Figure 1 A top plan view of one embodiment of a processing system 100 showing deposition, etch, bake, and cure chambers according to embodiments is shown. In the figure, a pair of front opening unified pods 102 supply substrates of various sizes that are received by a robot arm 104 and placed into a low pressure holding area 106 before being placed into one of the substrate processing chambers 108a-f positioned in tandem sections 109a-c. A second robot arm 110 can be used to transport substrate wafers from the holding area 106 to the substrate processing chambers 108a-f and back. Each substrate processing chamber 108a-f can be equipped to perform a number of substrate processing operations including, among others, plasma enhanced chemical vapor deposition, atomic layer deposition, physical vapor deposition, etching, pre-cleaning, degassing, orientation, and other substrate processing including annealing, ashing, etc., including formation of stacks of semiconductor materials described herein.

[0025] The substrate processing chambers 108a-f can include one or more system components for depositing, annealing, curing, and / or etching dielectric films or other films on a substrate. In one configuration, two pairs of processing chambers (e.g., 108c-d and 108e-f) can be used to deposit dielectric materials on a substrate, and a third pair of processing chambers (e.g., 108a-b) can be used to etch the deposited dielectric. In another configuration, all three pairs of chambers (e.g., 108a-f) can be configured to deposit stacks of alternating dielectric films on a substrate. Any one or more of the processes described can be performed in chambers separate from the manufacturing system shown in different embodiments. It will be appreciated that the system 100 contemplates additional configurations of deposition, etch, anneal, and cure chambers for dielectric films.

[0026] Figure 2A schematic cross-sectional view of an exemplary plasma system 200 according to some embodiments of the present technology is shown. Plasma system 200 can illustrate a pair of processing chambers 108 that can be fitted in one or more of the tandem sections 109 described above, and can include substrate support assemblies according to embodiments of the present technology. Plasma system 200 can generally include a chamber body 202 having sidewalls 212, a bottom wall 216, and an inner sidewall 201 that define a pair of processing regions 220A and 220B. Each of the processing regions 220A-220B can be similarly configured, and can include identical components.

[0027] For example, processing region 220B (components of which can also be included in processing region 220A) can include a susceptor 228 disposed in the processing region through a passage 222 formed in the bottom wall 216 of plasma system 200. Susceptor 228 can provide a heater adapted to support a substrate 229 on an exposed surface (such as a body portion) of the susceptor. Susceptor 228 can include a heating element 232 (e.g., a resistive heating element) that can heat and control the substrate temperature at a desired process temperature. Susceptor 228 can also be heated by a remote heating element (such as a lamp assembly) or any other heating device.

[0028] The body of susceptor 228 can be coupled to a stem 226 by a flange 233. Stem 226 can electrically couple susceptor 228 with a power outlet or power box 203. Power box 203 can include a drive system that controls the elevation and movement of susceptor 228 within processing region 220B. Stem 226 can also include a power interface to provide power to susceptor 228. Power box 203 can also include an interface for electrical power and temperature indicators, such as a thermocouple interface. Stem 226 can include a base assembly 238 adapted to be detachably coupled with power box 203. A peripheral ring 235 is shown above power box 203. In some embodiments, peripheral ring 235 can be a shoulder adapted to act as a mechanical stop or mechanical land configured to provide a mechanical interface between base assembly 238 and an upper surface of power box 203.

[0029] A stem 230 can be included through a passage 224 formed in the bottom wall 216 of processing region 220B, and can be used to position a substrate lift pin 261 disposed through the body of susceptor 228. Substrate lift pin 261 can selectively space substrate 229 from susceptor to facilitate replacement of substrate 229 with a robot used to transport substrate 229 into and out of processing region 220B through a substrate transfer port 260.

[0030] A chamber lid 204 can be coupled to the top of the chamber body 202. The lid 204 can house one or more precursor distribution systems 208 coupled thereto. The precursor distribution system 208 can include a precursor inlet passage 240 that can deliver reactant and cleaning precursors into the processing region 220B through a dual passage showerhead 218. The dual passage showerhead 218 can include an annular base plate 248 having a partition 244 disposed intermediate the faceplate 246. A radio frequency ("RF") source 265 can be coupled to the dual passage showerhead 218 that can power the dual passage showerhead 218 to facilitate the creation of a plasma region between the faceplate 246 of the dual passage showerhead 218 and the susceptor 228. In some embodiments, the RF source can be coupled to other portions of the chamber body 202, such as the susceptor 228, to facilitate the creation of a plasma. A dielectric isolator 258 can be disposed between the lid 204 and the dual passage showerhead 218 to prevent the conduction of RF power to the lid 204. A shadow ring 206 can be disposed on the periphery of the susceptor 228 that engages the susceptor 228.

[0031] An optional cooling channel 247 can be formed in the annular base plate 248 of the precursor distribution system 208 to cool the annular base plate 248 during operation. A heat transfer fluid, such as water, ethylene glycol, a gas, or the like, can be circulated through the cooling channel 247 such that the base plate 248 can be maintained at a predefined temperature. A liner assembly 227 can be disposed within the processing region 220B proximate the sidewalls 201, 212 of the chamber body 202 to prevent the sidewalls 201, 212 from being exposed to the processing environment within the processing region 220B. The liner assembly 227 can include a peripheral pumping cavity 225 that can be coupled to a pumping system 264 configured to exhaust gases and byproducts from the processing region 220B and control the pressure within the processing region 220B. A plurality of exhaust ports 231 can be formed in the liner assembly 227. The exhaust ports 231 can be configured to allow the flow of gases from the processing region 220B to the peripheral pumping cavity 225 in a manner that facilitates processing within the plasma system 200.

[0032] Figure 3 A schematic, partial cross-sectional view of an exemplary semiconductor processing chamber 300 according to some embodiments of the present technology is shown. Figure 3 may include one or more components discussed above with respect to Figure 2 and can illustrate further details related to such a chamber. The chamber 300 can be used to perform semiconductor processing operations, including deposition of stacks of dielectric materials as previously described. The chamber 300 can show a partial view of a processing region of a semiconductor processing system and can not include all components, such as additional lid stack components previously described, which should be understood to be incorporated into some embodiments of the chamber 300.

[0033] As described above, Figure 3 A portion of a processing chamber 300 can be illustrated. The chamber 300 can include a showerhead 305 and a substrate support assembly 310. The showerhead 305 and substrate support assembly 310 can define, along with chamber sidewalls 315, a substrate processing region 320 in which a plasma can be generated. The substrate support assembly can include an electrostatic chuck body 325, which can include one or more components embedded or disposed within the body. In some embodiments, components incorporated in a top puck can not be exposed to processing materials and can remain entirely within the chuck body 325. The electrostatic chuck body 325 can define a substrate support surface 327 and can be characterized by a thickness and a length or diameter depending on the particular geometry of the chuck body. In some embodiments, the chuck body can be elliptical and can be characterized by one or more radial dimensions from a central axis through the chuck body. It should be understood that the top puck can be any geometry and when discussing radial dimensions, the radial dimensions can define any length from a central location of the chuck body.

[0034] The electrostatic chuck body 325 can be coupled with a stem 330, which can support the chuck body and can include passages for conveying and receiving electrical wires and / or fluid lines that can be coupled with internal components of the chuck body 325 as will be discussed below. The chuck body 325 can include associated passages or components to operate as an electrostatic chuck, although in some embodiments, the assembly can operate as a vacuum chuck or any other type of chuck system, or include components for a vacuum chuck or components for any other type of chuck system. The stem 330 can be coupled with the chuck body on a second surface of the chuck body opposite the substrate support surface. The electrostatic chuck body 325 can include an electrode 335, which can be a DC electrode, embedded within the chuck body near the substrate support surface. The electrode 335 can be electrically coupled with a power source 340. The power source 340 can be configured to provide energy or voltage to the conductive chuck electrode 335. This can be operated to form a plasma of a precursor within the processing region 320 of the semiconductor processing chamber 300, although other plasma operations can similarly be maintained. For example, the electrode 335 can also be a chucking mesh that operates as an electrical ground for a capacitive plasma system that includes an RF source 307 electrically coupled with the showerhead 305. For example, the electrode 335 can operate as a ground path for RF power from the RF source 307 while also operating as an electrical bias to the substrate to electrostatically clamp the substrate to the substrate support surface. The power source 340 can include filters, power supplies, and a number of other electrical components configured to provide a chucking voltage.

[0035] In operation, a substrate can be at least partially in contact with a substrate support surface of the electrostatic chuck body, which can create a contact gap that can substantially create a capacitive effect between the surface of the pedestal and the substrate. A voltage can be applied to the contact gap, which can create electrostatic forces for adsorption. The power supply 340 can provide a charge that migrates from the electrode to the substrate support surface where the charge can accumulate, and the charge can create a charge layer with a coulombic attraction that has a charge opposite to the charge at the substrate, and can hold the substrate against the substrate support surface of the chuck body electrostatically. This charge migration can occur through a current flow through the dielectric material of the chuck body based on the finite resistance within the dielectric for Johnsen-Rahbek type adsorption, which can be used in some embodiments of the present technology.

[0036] The chuck body 325 can also define a recessed region 345 within the substrate support surface that can provide a recessed pocket in which a substrate can be disposed. The recessed region 345 can be formed at an interior region of the top puck and can be configured to receive a substrate for processing. The recessed region 345 can surround a central region of the electrostatic chuck body as shown, and can be sized to accommodate any variety of substrate sizes. A substrate can be located within the recessed region and contained by an outer region 347 that can surround the substrate. In some embodiments, the height of the outer region 347 can be such that the substrate is flush with or recessed below the surface height of the substrate support surface at the outer region 347. The recessed surface can control edge effects during processing, which in some embodiments can improve deposition uniformity across the substrate. In some embodiments, an edge ring can be disposed about the perimeter of the top puck and can at least partially define a recess in which a substrate can be located. In some embodiments, the surface of the chuck body can be substantially planar and the edge ring can completely define a recess in which a substrate can be located.

[0037] In some embodiments, the electrostatic chuck body 325 and / or the stem 330 can be an insulating or dielectric material. For example, oxides, nitrides, carbides, and other materials can be used to form the components. Exemplary materials can include ceramics (which include alumina, aluminum nitride, silicon carbide, tungsten carbide, and any other metal or transition metal oxide), nitrides, carbides, borides, or titanates, as well as combinations of these materials with other insulating or dielectric materials. Different grades of ceramic materials can be used to provide composite materials that are configured to operate within a particular temperature range, and thus in some embodiments, similar materials of different ceramic grades can be used for the top puck and the stem. As will be further explained below, dopants can be incorporated in some embodiments to adjust electrical properties. Exemplary dopant materials can include yttrium, magnesium, silicon, iron, calcium, chromium, sodium, nickel, copper, zinc, or any number of other elements known to be incorporated into ceramic or dielectric materials.

[0038] The electrostatic chuck body 325 can also include an embedded heater 350 contained within the chuck body. In embodiments, the heater 350 can include a resistive heater or a fluid heater. In some embodiments, the electrodes 335 can operate as a heater, but by decoupling these operations, more individual control can be provided and extended heater coverage can be provided while limiting the plasma formation area. The heater 350 can include a polymer heater interfaced or coupled with the chuck body material, although a conductive element can be embedded within the electrostatic chuck body and configured to receive an electrical current, such as an AC current, to heat the top puck. The electrical current can be delivered through the stem 330 through a channel similar to the DC power discussed above. The heater 350 can be coupled with a power source 365, which can provide the electrical current to the resistive heating element to facilitate heating of the associated chuck body and / or substrate. In embodiments, the heater 350 can include multiple heaters, and each heater can be associated with a region of the chuck body, and thus an example chuck body can include a similar or greater number of regions as the number of heaters. In some embodiments, the chucking mesh electrode 335 can be positioned between the heater 350 and the substrate support surface 327, and in some embodiments, a distance can be maintained between the electrode within the chuck body and the substrate support surface, as will be further described below.

[0039] The heater 350 can be capable of adjusting the temperature of the electrostatic chuck body 325 and a substrate positioned on the substrate support surface 327. The heater can have a range of operating temperatures to heat the chuck body and / or substrate above or about 100 °C, and the heater can be configured to heat above or about 125 °C, above or about 150 °C, above or about 175 °C, above or about 200 °C, above or about 250 °C, above or about 300 °C, above or about 350 °C, above or about 400 °C, above or about 450 °C, above or about 500 °C, above or about 550 °C, above or about 600 °C, above or about 650 °C, above or about 700 °C, above or about 750 °C, above or about 800 °C, above or about 850 °C, above or about 900 °C, above or about 950 °C, above or about 1000 °C, or higher. The heater can also be configured to operate within any range contained between any two of these stated numbers, or within a smaller range contained in any of these ranges. In some embodiments, as will be further described below, the chuck heater can be operated to maintain a substrate temperature above at least 500 °C during a deposition operation, such as the formation of a stack of materials for a memory device as previously described.

[0040] Figure 4 A schematic partial cross-sectional view of an exemplary substrate support assembly 400 according to some embodiments of the present technology is shown. The substrate support assembly 400 can include any of the previously described materials or components, and can illustrate additional details of the previously discussed substrate support assemblies. As shown, an electrostatic chuck body 405 can include an embedded electrode 410 and an embedded heater 415 as previously described. A substrate support surface 406 can be defined by the chuck body and can be configured to support a semiconductor substrate 430. The substrate support surface can define a pocket 408 within the substrate support surface. A recessed ledge 420 can also be defined in the substrate support surface. The recessed ledge can extend radially inward from the outer radial edge of the pocket. Additionally, the substrate support surface can define a number of protrusions 425 extending from the substrate support surface within the pocket 408. The exposed surfaces across the protrusions 425 can define contact locations at which the substrate 430 can contact the substrate support surface.

[0041] As described above, in embodiments, a power source can be provided for each of the heater 415 and the electrodes 410, which can be any number of power sources. For example, the power source for the electrodes can be a DC power source or any other power source, and can provide a range of voltages configured to attract the substrate to the substrate support surface 406. For example, a relatively high power source can be used for systems in accordance with some embodiments of the present technology to facilitate attraction of substrates having thicker deposited layers, which can be characterized by larger stresses that result in bowing. As one non-limiting example, for ON stacks, the forces on the substrate can increase as the number of pairs of layers increases. Higher temperatures can induce these forces, further increasing the amount of bowing and challenging the ability to properly attract the substrate to the support assembly.

[0042] To compensate for these forces, an increased attraction voltage can be used to maintain a substantially flat substrate surface, although some amount of bowing can still occur. As these pairs of layers continue to increase, the minimum voltage to maintain attraction can continue to increase. Thus, in some embodiments, the minimum attraction voltage can be higher than or about -250 V, and depending on the stresses and the number of pairs to be compensated for, the minimum chuck voltage can be higher than or about -300 V, higher than or about -350 V, higher than or about -400 V, higher than or about -450 V, higher than or about -500 V, higher than or about -550 V, higher than or about -600 V, higher than or about -650 V, higher than or about -700 V, higher than or about -750 V, higher than or about -800 V, higher than or about -850 V, higher than or about -900 V, higher than or about -950 V, higher than or about -1000 V, or higher.

[0043] However, as noted above, these deposition operations can be performed at elevated temperatures, which can directly impact the resistivity of the chuck body material and the ability of this material to properly operate as a J-R chuck. For example, electrostatic chuck body 405 can be, for example, aluminum nitride, which can be characterized by a bulk resistance at a certain temperature. As the temperature of the material increases, the resistance decreases, and for example, the resistance can decrease significantly at temperatures above 500°C. As the resistance decreases, the likelihood of arcing or electrostatic discharge can increase. Additionally, to limit significant bowing of the substrate that can occur during these depositions, increased voltages can be used to maintain the chucking. However, as this voltage increases, the likelihood of arcing around the area of lugs 420 can similarly increase, which can limit the amount of voltage that can be applied for chucking, and this can limit the ability to offset bowing. Conventionally, this results in damage to the product and reduces the quality of the product.

[0044] However, in contrast to conventional techniques, the present technology utilizes materials and configurations that can facilitate an increased voltage window without resulting in arcing. For example, conventional techniques can arc at clamp voltages above or around -300V or around -350V. This voltage can not be sufficient to offset the film stress created during multi-layer stack deposition, such as ON deposition with tens or hundreds of layers of material. The present technology can facilitate chucking at voltages between about -500V and about -1000V, and including between about -600V and about -800V, which can accommodate stress associated with a larger number of deposition layers while limiting arcing from the pedestal.

[0045] For J-R chucking, as the temperature increases due to changes in resistance within the pedestal material, the chucking force typically increases to a saturation level, facilitating the migration of charge to the surface of the chuck body, such as lugs 425, which can directly contact the substrate. However, this conventionally results in arcing around the substrate as the chucking voltage is increased to accommodate increased substrate bowing. The present technology improves upon these deficiencies by providing an assembly that can operate at increased chucking voltages to offset increased substrate stress by reducing the leakage current in the substrate support assembly. Leakage current is an indicator of migration within the substrate support material, which can be measured in terms of leakage occurring from the electrode to the heater.

[0046] Conventional technology can accept a leakage current above or about 10 mA at certain operating temperatures, which can increase dramatically at operating temperatures above 500 °C. While conventional technology can consider leakage current in terms of insulation layer damage or substrate damage, relatively high leakage currents can be accepted to increase adhesion. However, this results in increased arcing in conventional designs. The present technology modifies aspects and characteristics of the substrate support assembly to limit leakage current by effectively increasing the resistivity of the substrate support material to limit leakage current while maintaining adhesion at the substrate. Thus, the present technology produces a substrate support assembly characterized by a resistivity based on leakage current that is maintained within a range to properly adhere a substrate characterized by the previously described stresses while also limiting or preventing arcing due to higher adhesion voltages.

[0047] The present technology can limit leakage current at temperatures above or about 500 °C, and can limit leakage current at temperatures above or about 550 °C, above or about 600 °C, above or about 650 °C, above or about 700 °C, above or about 750 °C, or higher. The present technology can also limit leakage current at adhesion voltages above or about 400 V, and can limit leakage current at adhesion voltages above or about 450 V, above or about 500 V, above or about 550 V, above or about 600 V, above or about 650 V, above or about 700 V, above or about 750 V, above or about 800 V, above or about 850 V, above or about 900 V, or higher. The present technology can limit leakage current to less than or about 10 mA in these temperature and voltage ranges, and can limit leakage current to less than or about 8 mA, less than or about 6 mA, less than or about 5 mA, less than or about 4 mA, less than or about 3.5 mA, less than or about 3 mA, less than or about 2.5 mA, less than or about 2 mA, less than or about 1.5 mA, or less. However, in some embodiments, leakage current can be maintained above or about 0.2 mA to ensure sufficient mobility to facilitate J-R adhesion, and in some embodiments can be maintained greater than or about 0.3 mA, greater than or about 0.5 mA, greater than or about 0.7 mA, greater than or about 1.0 mA, or greater.

[0048] As described above, JR adsorption can be based at least in part on the resistance of the contact layer disposed between the substrate and the base. The resistance can be adjusted by regulating the distance between the electrode and the contact surface of the electrostatic chuck body. The increased temperature in some embodiments of this technology, because the state can be a relatively plateau along the adsorption force, can substantially maintain or minimally reduce the adsorption force. Therefore, in some embodiments, the electrode can be further embedded from the contact surface in some embodiments, which can effectively increase the resistance of the substrate support assembly to reduce leakage current that may contribute to arcing.

[0049] For example, such as Figure 4 As shown, the contact surface can be formed along the outermost (e.g., the uppermost) surface of the substrate support assembly in the recess 408, which may be the top surface of the protrusion 425. Starting from this plane, the electrode 410 can be embedded to a certain depth within the substrate support assembly to maintain a minimum distance between the electrode and the substrate support surface. For example, in some embodiments, the electrode 410 may be embedded within the electrostatic chuck body at a distance or depth greater than 2 mm or approximately 2 mm from the substrate support surface 406, and depending on the characteristics of the substrate support assembly, it may be embedded at a distance greater than 2 mm or approximately 2 mm, greater than 3 mm or approximately 3 mm, greater than 4 mm or approximately 4 mm, greater than 5 mm or approximately 5 mm, greater than 6 mm or approximately 6 mm, greater than 7 mm or approximately 7 mm, greater than 8 mm or approximately 8 mm, greater than 9 mm or approximately 9 mm, greater than 10 mm or approximately 10 mm, greater than 12 mm or approximately 12 mm, greater than 14 mm or approximately 14 mm, greater than 16 mm or approximately 16 mm, greater than 18 mm or approximately 18 mm, greater than 20 mm or approximately 20 mm, or greater.

[0050] The electrostatic chuck body 405 may also be or comprise a material characterized by a specific volume resistivity. As mentioned above, the chuck body may be or comprise a ceramic material (such as aluminum nitride) or any of the materials discussed above. In some embodiments, the material may be selected, doped, or produced (such as sintered) to provide a volume resistivity above a threshold. For example, in some embodiments, the chuck body may be or comprise a dielectric material (such as aluminum nitride) having a resistivity greater than 5 × 10⁻⁶ at temperatures above or about 550°C, above 600°C or about 600°C, above or about 650°C, or higher. 8 Ohm-cm or approximately 5 × 10⁻⁶ 8 The volume resistivity is characterized by ohm-cm, and the dielectric material can be greater than 1×10⁻⁶ at any of these temperature ranges. 9 Ohm-cm or approximately 1×10 9 Ohm-cm, greater than 5×10 9Ohm-cm or approximately 5 × 10⁻⁶ 9 Ohm-cm, greater than 1×10 10 Ohm-cm or approximately 1×10 10 Ohm-cm, greater than 3×10 10 Ohm-cm or approximately 3 × 10⁻⁶ 10 Ohm-cm, greater than 5×10 10 Ohm-cm or approximately 5 × 10⁻⁶ 10 Ohm-cm, greater than 7×10 10 Ohm-cm or approximately 7 × 10⁻⁶ 10 Ohm-cm, greater than 1×10 11 Ohm-cm or approximately 1×10 11 Ohm-cm, greater than 3×10 11 Ohm-cm or approximately 3 × 10⁻⁶ 11 Ohm-cm, greater than 5×10 11 Ohm-cm or approximately 5 × 10⁻⁶ 11 Ohm-cm, greater than 7×10 11 Ohm-cm or approximately 7 × 10⁻⁶ 11 Ohm-cm, greater than 1×10 12 Ohm-cm or approximately 1×10 12 It is characterized by volume resistivity of ohm-cm or greater.

[0051] For example, the effective resistivity can also be adapted by adjusting the amount of contact between the substrate and the substrate support assembly. Figure 4 As shown, a plurality of protrusions 425 may be included or defined along the substrate support surface 406. The protrusions can provide contact points spanning a planar area or recessed pocket across the substrate support surface. Thus, the substrate can contact the substrate support assembly along a certain percentage of its surface area. Conventional techniques can provide various levels of contact (such as above 60% or about 60%), medium contact (such as about 40%), and low contact (which can be less than 20%). However, each of these ranges can provide increased leakage current compared to this technique. Alternative low-contact systems providing less than 1% contact may also be insufficient, as these systems may not generate sufficient clamping force to accommodate substrate bending. This technique increases the percentage of surface area contact used for JR adsorption while additionally using a protrusion pattern to adjust the clamping characteristics.

[0052] A substrate 430 positioned on the substrate support surface 406 can contact each of the protrusions 425 and can additionally extend at least partially across the ledge 420 within the pocket 408. The present technology can increase the percentage of contact along a wafer by increasing the number of protrusions. For example, the present technology can form protrusions characterized by a diameter or width of about 1 mm, about 2 mm, or greater, and in some embodiments can include a combination of protrusions characterized by a diameter of greater than 1 mm or about 1 mm and protrusions characterized by a diameter of greater than 2 mm or about 2 mm. In embodiments of the present technology, the protrusions can be characterized by any number of geometries and profiles. For an exemplary substrate support assembly, the substrate support surface within the pocket can define more than or about 250 protrusions, and can define more than or about 500 protrusions, more than or about 750 protrusions, more than or about 1000 protrusions, more than or about 1250 protrusions, more than or about 1500 protrusions, more than or about 1750 protrusions, more than or about 2000 protrusions, or more. The protrusions can be defined in any number of formations or patterns, including uniform patterns and overall distributions across the surface.

[0053] Additionally, an outermost subset 427 of the protrusions 425 can maintain a distance of less than 5 mm or about 5 mm from the inner radial edge of the ledge 420 adjacent the protrusions. In some embodiments, the outermost subset of protrusions can maintain a distance of less than 4.5 mm or about 4.5 mm from the inner radial edge of the ledge 420, and can maintain a distance of less than 4.0 mm or about 4.0 mm, less than 3.5 mm or about 3.5 mm, less than 3.0 mm or about 3.0 mm, less than 2.5 mm or about 2.5 mm, less than 2.0 mm or about 2.0 mm, less than 1.5 mm or about 1.5 mm, less than 1.0 mm or about 1.0 mm, or less from the inner radial edge of the ledge 420. By maintaining the protrusions within this distance, the torque on the outermost regions of the substrate can be maintained or increased, which can further facilitate clamping to compensate for bowing of the substrate.

[0054] By creating protrusions according to some embodiments of the present technology, the percentage of contact along the surface of the substrate can be increased to be greater than 1.0% or about 1.0%, and can be greater than 1.5% or about 1.5%, greater than 2.0% or about 2.0%, greater than 2.5% or about 2.5%, greater than 3.0% or about 3.0%, greater than 3.5% or about 3.5%, greater than 4.0% or about 4.0%, greater than 4.5% or about 4.5%, greater than 5.0% or about 5.0% or greater. The percentage of contact can be maintained to be less than 10% or about 10% to limit the leakage current to below the aforementioned ranges, and the contact can be limited to be less than 8% or about 8%, less than 6% or about 6%, less than 5% or about 5% or less. When the amount of contact along the lugs 420 is not included, the percentage of contact provided by the protrusions can be maintained to be greater than 0.2% or about 0.2% of the surface area of the substrate surface along the substrate support assembly, or greater than 0.2% of the surface area of the substrate surface along the substrate support assembly. In some embodiments, excluding the contribution of the lugs, the percentage of contact provided by the protrusions can be maintained to be greater than 0.3% or about 0.3%, greater than 0.4% or about 0.4%, greater than 0.6% or about 0.6%, greater than 0.8% or about 0.8%, greater than 1.0% or about 1.0%, greater than 1.2% or about 1.2%, greater than 1.4% or about 1.4%, greater than 1.6% or about 1.6%, greater than 1.8% or about 1.8%, greater than 2.0% or about 2.0%, greater than 2.2% or about 2.2%, greater than 2.4% or about 2.4%, greater than 2.6% or about 2.6%, greater than 2.8% or about 2.8%, greater than 3.0% or about 3.0% or greater. By providing a substrate support assembly characterized by controlled leakage current, the present technology can provide an increased window of chucking that can appropriately hold substrates characterized by increased film stress while limiting or preventing arcing within a plasma environment.

[0055] Figure 5 A schematic partial cross-sectional view of an exemplary substrate support assembly 500 according to some embodiments of the present technology is shown. The substrate support assembly 500 can include any of the previously described materials or components, and can illustrate additional details of the previously discussed substrate support assemblies. For example, the previously discussed protrusions can be distributed across the surface of the substrate support in any pattern. While a uniform distribution can be used, in some embodiments, a non-uniform distribution of protrusions can be used. Figure 5An example distribution encompassed by the present technology is illustrated in which the protrusions 525 can be distributed in an annular pattern extending radially outward on the substrate support. Each annulus can have more or fewer protrusions than the radially inward annulus, and the distribution can increase in density at the outer regions of the substrate support. For example, as illustrated, the radially outer portion of the substrate support can include an increased density of protrusions, which can improve adsorption as previously described. The present technology similarly encompasses any number of other distribution patterns.

[0056] In the preceding description, for purposes of explanation, numerous details are set forth in order to provide an understanding of various embodiments of the present technology. However, it will be apparent to one skilled in the art that certain embodiments can be practiced without some or all of these details.

[0057] Having disclosed several embodiments, those skilled in the art will recognize that various modifications, alternative constructions, and equivalents can be used without departing from the spirit of the embodiments. Additionally, many known processes and elements are not described in detail in order to avoid unnecessarily obscuring the present technology. Accordingly, the above description should not be taken as limiting on the scope of the present technology.

[0058] In providing ranges of values, it is to be understood that unless otherwise explicitly stated in the context of a recited range, every intermediate value of the range is also specifically disclosed. Any narrower ranges falling within the scope of a recited range are also specifically disclosed. The upper and lower limits of these smaller ranges can independently be included or excluded in the smaller ranges, and each individual value within the smaller ranges is also encompassed. Where the stated range includes one or both of the limits, ranges excluding either or both of the limits are also included.

[0059] As used in this document and in the appended claims, the singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. Thus, for example, reference to “a heater” includes a plurality of such heaters, and reference to “the protrusion” includes reference to one or more protrusions and equivalents known to those skilled in the art, and so forth.

[0060] Likewise, the words "comprise(s)," "comprising," "contain(s)," "containing," "include(s)," and "including," when used in this specification and in the following claims, are intended to specify the presence of stated features, integers, components, or operations but do not preclude the presence or addition of one or more other features, integers, components, operations, acts, or groups.

Claims

1. A substrate support assembly, comprising: An electrostatic chuck body, wherein the electrostatic chuck body defines a substrate support surface; A support rod, which is coupled to the electrostatic chuck body; Heater, which is embedded in the electrostatic chuck body; as well as An electrode is embedded within the electrostatic chuck body between the heater and the substrate support surface, wherein the electrostatic chuck body defines a recess along the substrate support surface, the recess surrounding a central region of the electrostatic chuck body, wherein the substrate support surface defines a recessed lug extending radially inward from the outer radial edge of the recess, and wherein the substrate support assembly is characterized by a leakage current of less than or equal to 4 mA through the electrostatic chuck body at a temperature greater than or equal to 500°C and a voltage greater than or equal to 600V.

2. The substrate support assembly of claim 1, wherein the electrostatic chuck body defines a plurality of protrusions extending from the substrate support surface within the recessed pouch.

3. The substrate support assembly of claim 2, wherein the distance between the outermost radial protrusion and the inner radial edge of the recessed lug is maintained at less than or equal to 3 mm.

4. The substrate support assembly of claim 2, wherein the electrostatic chuck body defines more than or equal to 500 protrusions, and each of the plurality of protrusions is characterized by a diameter greater than or equal to 1 mm, a subset of the plurality of protrusions is characterized by a diameter greater than or equal to 2 mm, wherein the plurality of protrusions defines a contact area with respect to a substrate located on the substrate support surface of the electrostatic chuck body, and wherein the contact area is less than or equal to 10% of the planar area of ​​the substrate.

5. The substrate support assembly as claimed in claim 1, wherein the electrostatic chuck body is a ceramic material, the ceramic material being formed by reacting a material at a temperature greater than or equal to 550°C with a density greater than or equal to 1×10⁻⁶. 9 It is characterized by volume resistivity in ohm-cm.

6. A substrate support assembly, comprising: An electrostatic chuck body, wherein the electrostatic chuck body defines a substrate support surface; Heater, which is embedded in the electrostatic chuck body; as well as An electrode is embedded within the electrostatic chuck body between the heater and the substrate support surface, wherein the electrode is maintained at a distance of at least 3 mm from the substrate support surface within the electrostatic chuck body, wherein the electrostatic chuck body defines a recessed pocket within the substrate support surface, the recessed pocket being configured to receive a substrate for processing, wherein the substrate support surface defines a recessed lug extending radially inward from the outer radial edge of the recessed pocket, and wherein the substrate support assembly is characterized by a leakage current of less than or equal to 4 mA through the electrostatic chuck body at a temperature greater than or equal to 540°C and a voltage greater than or equal to 660 V.

7. The substrate support assembly of claim 6, wherein the electrode is positioned within the electrostatic chuck body at a depth of at least 5 mm from the substrate support surface of the electrostatic chuck body.

8. The substrate support assembly of claim 6, wherein the electrostatic chuck body comprises a ceramic material, the ceramic material being formed by reacting a material at a temperature greater than or equal to 600°C with a density greater than or equal to 1×10⁻⁶. 9 It is characterized by volume resistivity in ohm-cm.

9. The substrate support assembly of claim 6, wherein the electrostatic chuck body defines a plurality of protrusions extending from the substrate support surface within the recessed pouch, wherein the plurality of protrusions define a contact area for a substrate located on the substrate support surface of the electrostatic chuck body, and wherein the contact area is less than or equal to 5% of the planar area of ​​the substrate.

10. The substrate support assembly of claim 6, wherein the substrate support assembly is characterized by a leakage current of less than or equal to 4 mA through the electrostatic chuck body at a temperature greater than or equal to 600°C and a voltage greater than or equal to 800V.

11. A substrate support assembly, comprising: An electrostatic chuck body, wherein the electrostatic chuck body defines a substrate support surface; A support rod, which is coupled to the electrostatic chuck body; Heater, which is embedded in the electrostatic chuck body; as well as An electrode is embedded within the electrostatic chuck body between the heater and the substrate support surface, wherein the electrode is maintained at a distance of at least 5 mm from the substrate support surface within the electrostatic chuck body, wherein the electrostatic chuck body defines a recess along the substrate support surface, the recess surrounding a central region of the electrostatic chuck body, wherein the substrate support surface defines a recessed lug extending radially inward from the outer radial edge of the recess, and wherein the substrate support assembly is characterized by a leakage current of less than or equal to 4 mA through the electrostatic chuck body at a temperature greater than or equal to 550°C and a voltage greater than or equal to 650V.

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