Semiconductor substrate support with embedded RF shield

Abstract

An exemplary support assembly may include a top disk defining a substrate support surface, wherein the top disk is further characterized by a height. The assembly may include a rod coupled to the top disk on a second surface of the top disk opposite the substrate support surface. The assembly may include RF electrodes embedded within the top disk near the substrate support surface. The assembly may include a heater embedded within the top disk. The assembly may also include a grounding shield embedded within the top disk. The grounding shield may be characterized by an inner region extending radially through the top disk. The grounding shield may be further characterized by an outer region extending perpendicular to the inner region.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Patent Application No. 16 / 131,972, filed on September 14, 2018, the disclosure of which is incorporated herein in its entirety for all purposes. Technical Field

[0003] The present technology relates to components and equipment used in semiconductor manufacturing. More specifically, the present technology relates to substrate support assemblies and other semiconductor processing equipment. Background Art

[0004] Integrated circuits are made possible by processes that produce intricately patterned layers of material on a substrate surface. Producing patterned materials on a substrate requires controlled methods for forming and removing materials. The temperatures at which these processes occur can directly affect the final product. The substrate temperature is typically controlled and maintained by components that support the substrate during processing. Internally located heating devices can generate heat within the support that can be conductively transferred to the substrate. The substrate support can also be used in some technologies to generate plasma at the level of the substrate. Plasma generated near the substrate can cause bombardment of components and the formation of parasitic plasma in unfavorable areas of the chamber. In addition, the use of a pedestal for both heat generation and plasma generation can cause interference effects.

[0005] Since various operating processes may utilize elevated temperatures and plasma formation at the substrate level, the constituent materials of the substrate support may be exposed to corrosive and erosive materials. Therefore, there is a need for improved systems and methods that can be used to produce high-quality devices and structures. These and other needs are addressed by the present technology. Summary of the invention

[0006] An exemplary support assembly may include a top disk defining a substrate support surface, wherein the top disk is further characterized by a height. The assembly may include a rod coupled to the top disk on a second surface of the top disk opposite the substrate support surface. The assembly may include an RF electrode embedded in the top disk at a location proximate to the substrate support surface. The assembly may include a heater embedded in the top disk. The assembly may also include a grounded shield or a Faraday cage embedded in the top disk. The grounded shield may be characterized by an inner region extending radially through the top disk. The grounded shield may be further characterized by an outer region extending perpendicular to the inner region.

[0007] In some embodiments, the ground shield may be further characterized by an outer region extending perpendicular to the inner region, and the outer region of the ground shield may extend vertically, at least partially through the height of the top disk. The top disk may define a recess in the substrate support surface, the recess being configured to receive a substrate for processing. The top disk may include a ceramic material. A heater may be positioned in the top disk at a position between the RF electrode and the ground shield. The heater may be configured to heat the substrate supported by the top disk to a temperature greater than or about 300° C. The heater may include a first heater and a second heater, the second heater being controllable independently of the first heater, and the second heater may extend around an outer edge of the first heater. The assembly may further include a rod coupled to the top disk on a second surface of the top disk opposite to the substrate support surface. The rod may define an internal channel, the RF rod extending through the internal channel and coupled to the RF electrode. The assembly may also include a ground loop, the ground loop extending through the internal channel coaxially with the RF rod. The assembly may also include a ground impedance electrode disposed in the top disk at a position near the substrate support surface.

[0008] Some embodiments of the present technology may also include a substrate support assembly. The assembly may include a top disk that defines a substrate support surface and is characterized by a height. The assembly may include a rod that is coupled to the top disk on a second surface of the top disk opposite the substrate support surface. The assembly may include an RF electrode that is embedded in the top disk at a position near the substrate support surface. The assembly may include a heater embedded in the top disk. The assembly may also include a ground shield embedded in the top disk. The ground shield may include a base that extends radially through the top disk. The ground shield may also include an intermediate ring positioned vertically between the ground shield base and the RF electrode, and the intermediate ring may be electrically coupled to the base.

[0009] In some embodiments, the top disk may define a recess within the substrate support surface, the recess being configured to receive a substrate for processing. The top disk and the rod may include a ceramic material. A heater may be positioned within the top disk at a position between the RF electrode and the ground shield. The heater may be configured to heat the substrate supported by the top disk to a temperature greater than or about 300° C. The heater may include a first heater and a second heater. The second heater may be controlled independently of the first heater, and the second heater may extend around the outer edge of the first heater. The assembly may also include a ground impedance electrode disposed within the top disk at a position near the substrate support surface. The ground impedance electrode may be coupled to ground along a ground path separated from the ground shield. The assembly may also include a conductive post extending vertically within the top disk and electrically coupling an intermediate ring of the ground shield to a base of the ground shield. The intermediate ring may include a plurality of intermediate rings vertically offset from each other within the top disk. Each of the plurality of intermediate rings may be positioned within 1 cm of an adjacent ring within the top disk.

[0010] Such techniques may provide numerous benefits over conventional systems and techniques. For example, embodiments of the present technology may provide a substrate support that may both generate a substrate-level plasma and provide high temperature operation. Additionally, by incorporating an internal grounded shield, material erosion and corrosion may be limited or prevented. These and other embodiments and their many advantages and features are described in more detail in conjunction with the following description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] A further understanding of the nature and advantages of the disclosed technology may be realized by reference to the remainder of the specification and drawings.

[0012] Figure 1 A top plan view of an exemplary processing system in accordance with some embodiments of the present technology is shown.

[0013] Figure 2A A schematic cross-sectional view of an exemplary processing chamber according to some embodiments of the present technology is shown.

[0014] Figure 2B A detailed view of an exemplary spray head is shown in accordance with some embodiments of the present technology.

[0015] Figure 3 A bottom plan view of an exemplary showerhead according to some embodiments of the present technology is shown.

[0016] Figure 4 A schematic partial cross-sectional view of an exemplary semiconductor processing chamber in accordance with some embodiments of the present technology is shown.

[0017] Figure 5A schematic partial cross-sectional view of an exemplary substrate support assembly in accordance with some embodiments of the present technology is shown.

[0018] Figure 6 A schematic partial cross-sectional view of an exemplary substrate support assembly in accordance with some embodiments of the present technology is shown.

[0019] The drawings are included as schematic diagrams. It should be understood that the drawings are for illustration purposes only and should not be considered to be drawn to scale unless specifically noted as being drawn to scale. Additionally, the drawings are provided as schematic diagrams to aid understanding; and may not include all aspects or information as compared to actual representation; and may include exaggerated material for illustration purposes.

[0020] In the drawings, similar components and / or features may have the same reference numeral. In addition, various components of the same type may be distinguished by following the reference numeral with a letter that distinguishes between similar components. If only the first reference numeral is used in the specification, the description applies to any of the similar components having the same first reference numeral, regardless of the letter. DETAILED DESCRIPTION

[0021] Some etching processes may include multiple operations including ion bombardment operations at the substrate level from plasmas generated from inert precursors, and chemical processes that may or may not include plasma generation, but may include etchant precursors, such as halogen-containing precursors. Additionally, with developed small-scale etching processes, such as certain atomic layer etching, higher temperature operation may be beneficial to the etching process. When a substrate support assembly is used for plasma generation as well as heat generation, operating conditions and parameters may be problematic.

[0022] For example, biased plasma may be generated at the substrate level using embedded electrodes within a substrate support. For example, when the electrode emits energy such as RF energy, waves may be emitted in all directions, and plasma may be generated based on a location where a large amount of ground coupling may occur. In many operations, a cover or panel may be located above the substrate support and a processing area may be defined between the substrate on the support and the overlying components. Typically, this is the area where plasma is preferably generated. However, based on many chamber designs, the substrate support may be positioned near the chamber sidewall and / or near the chamber bottom below the substrate support. Therefore, a relatively close ground path may be provided to the chamber sidewall. This may generate parasitic plasma on the sides of the substrate support and below the substrate support. This plasma not only limits processing capabilities, but may also cause additional damage to exposed chamber components in these areas.

[0023] Therefore, a ground shield is typically formed around the substrate support. Many conventional ground shields include a conductive material that extends along a rod and runs along the base and sides of a disk on which the substrate resides. Subsequently, the ground shield can be operated to limit emission through the base, and the plasma can be better contained within the processing area. However, the ground shield in this configuration is exposed to both ion bombardment that can erode the ground shield material and chemical etchants that can corrode the ground shield material. Therefore, many of these configurations are limited to lower temperature operations, which can allow for protection of the ground shield, which can be in the form of a coating that cannot be maintained under higher temperature operations. For example, an aluminum ground shield may begin to deform or melt at temperatures exceeding 450°C and may actively corrode from chemical etchants at these temperatures. In addition, when the temperature exceeds 300°C, many oxide coatings will begin to peel off, which may expose underlying materials that can be etched or corroded by plasma species.

[0024] The present technology overcomes these challenges by forming a grounded shield or Faraday cage within the substrate support, which may be used synonymously in the present disclosure. In such a configuration, the grounded shield may not be exposed to process precursors, which may protect the shield during operation. Additionally, operations may be performed at higher temperatures, where conventional technologies may suffer from peeling of the coating on the grounded shield and deformation or melting of the grounded shield itself.

[0025] Although the remainder of this disclosure will routinely identify specific etching processes utilizing the disclosed techniques, it will be readily appreciated that the systems and methods are equally applicable to deposition, cleaning chambers, and processes that may occur in the chambers. Thus, the present technology should not be considered limited to use with only etching processes or chambers. This disclosure will discuss one possible system and chamber in which a base according to embodiments of the present technology may be used, and then describe additional variations and adjustments to this system according to embodiments of the present technology.

[0026] Figure 1A top plan view of one embodiment of a processing system 100 of deposition, etching, baking and curing chambers according to an embodiment is shown. In the figure, a pair of front opening unification units (FOUPs) 102 provide substrates of various sizes, which are received and placed into a low pressure holding area 106 by a robot 104 before being placed into one of the substrate processing chambers 108a-108f positioned in the serial connection section 109a-109c. A second robot 110 can be used to transfer substrate wafers from the holding area 106 to the substrate processing chambers 108a-108f and back. Each substrate processing chamber 108a-108f can be configured to perform a plurality of substrate processing operations, which include dry etching processes described herein in addition to cyclic layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etching, pre-cleaning, degassing, orientation, and other substrate processes including annealing, ashing, etc.

[0027] The substrate processing chambers 108a-108f may include one or more system components for depositing, annealing, curing and / or etching dielectric films on substrate wafers. In one configuration, two pairs of processing chambers (e.g., 108c-108d and 108e-108f) may be used to deposit dielectric materials on substrates, and a third pair of processing chambers (e.g., 108a-108b) may be used to etch the deposited dielectric. In another configuration, all three pairs of chambers (e.g., 108a-108f) may be configured to etch dielectric films on substrates. Any one or more of the described processes may be performed in (multiple) chambers separate from the manufacturing system shown in different embodiments. It should be understood that the system 100 contemplates other configurations of deposition, etching, annealing and curing chambers for dielectric films.

[0028] Figure 2A A cross-sectional view of an exemplary process chamber system 200 having a plasma generation region separated within a processing chamber is shown. During film etching (e.g., titanium nitride, tantalum nitride, tungsten, silicon, polysilicon, silicon oxide, silicon nitride, silicon oxynitride, silicon oxycarbide, etc.), a process gas may flow into a first plasma region 215 via a gas inlet assembly 205. A remote plasma system (RPS) 201 may optionally be included in the system and may process a first gas, which then travels through the gas inlet assembly 205. The inlet assembly 205 may include two or more different gas supply channels, wherein a second channel (not shown) may bypass the RPS 201 if included.

[0029] A cooling plate 203, a face plate 217, an ion suppressor 223, a showerhead 225, and a substrate support 265 (with a substrate 255 disposed thereon) are shown and may each be included depending on the embodiment. The base 265 may have heat exchange channels through which a heat exchange fluid flows to control the temperature of the substrate, which may be operated to heat and / or cool the substrate or wafer during processing operations. Embedded resistive heater elements may also be used to resistively heat a wafer support disk of the base 265 (the wafer support disk may include aluminum, ceramic, or a combination thereof) to achieve relatively high temperatures (such as from up to or about 100° C. to above or about 1100° C.).

[0030] The faceplate 217 may be pyramidal, conical, or another similar structure having a narrow top portion extending to a wide bottom portion. As shown, the faceplate 217 may additionally be flat and include a plurality of channels for distributing process gases. Depending on the use of the RPS 201, the plasma-generating gas and / or the plasma-inducing substance may pass through a plurality of holes (e.g., Figure 2B ), for more uniform delivery into the first plasma region 215.

[0031] An exemplary configuration may include opening the gas inlet assembly 205 into a gas supply region 258 separated from the first plasma region 215 by a faceplate 217 such that the gas / species flows through holes in the faceplate 217 into the first plasma region 215. Structural and operational features may be selected to prevent significant backflow of plasma from the first plasma region 215 into the supply region 258, the gas inlet assembly 205, and the fluid supply system 210. The faceplate 217 or conductive top portion of the chamber and the showerhead 225 are shown with an insulating ring 220 located between these features, which allows an AC potential to be applied to the faceplate 217 relative to the showerhead 225 and / or the ion suppressor 223. The insulating ring 220 may be positioned between the faceplate 217 and the showerhead 225 and / or the ion suppressor 223 to enable formation of a capacitively coupled plasma (CCP) in the first plasma region. Baffles (not shown) may additionally be located in the first plasma region 215 or otherwise coupled to the gas inlet assembly 205 to affect the flow of fluid entering the region through the gas inlet assembly 205 .

[0032] The ion suppressor 223 may include a plate or other geometric shape that defines a plurality of apertures throughout the structure that are configured to suppress the migration of ionic charged species from the first plasma region 215 while allowing uncharged neutral or radical species to pass through the ion suppressor 223 into the activated gas delivery region between the suppressor and the showerhead. In embodiments, the ion suppressor 223 may include a perforated plate having various aperture configurations. These uncharged species may include highly reactive species that are delivered through the apertures with a less reactive carrier gas. As described above, the migration of ionic species through the apertures may be reduced, and in some cases the migration of ionic species through the apertures may be completely suppressed. Controlling the amount of ionic species passing through the ion suppressor 223 may advantageously provide increased control over the gas mixture in contact with the underlying wafer substrate, which in turn may increase control over the deposition and / or etching characteristics of the gas mixture. For example, adjustments to the ion concentration of the gas mixture may significantly change the etching selectivity (e.g., SiNx:SiOx etching ratio, Si:SiOx etching ratio, etc.) of the gas mixture. In alternative embodiments of performing the deposition, it may also change the balance of the conformal to flowable pattern deposition of the dielectric material.

[0033] The plurality of apertures in the ion suppressor 223 can be configured to control the flow of activated gas (i.e., ions, radicals, and / or neutral species) through the ion suppressor 223. For example, the aspect ratio of the apertures, or the ratio of the diameter to the length of the apertures, and / or the geometry of the apertures can be controlled so that the flow of ionic charged species in the activated gas through the ion suppressor 223 is reduced. The apertures in the ion suppressor 223 can include a conical portion facing the plasma excitation region 215 and a cylindrical portion facing the showerhead 225. The cylindrical portion can be shaped and sized to control the flow of ionic species to the showerhead 225. An adjustable electrical bias can also be applied to the ion suppressor 223 as an additional means of controlling the flow of ionic species through the suppressor.

[0034] The ion suppressor 223 can function to reduce or eliminate the amount of ionic charged species that travel from the plasma generation region to the substrate. Uncharged neutral and free radical species can still react with the substrate through the openings in the ion suppressor. It should be noted that in embodiments, complete elimination of ionic charged species in the reaction region surrounding the substrate may not be performed. In some cases, ionic species are intended to reach the substrate in order to perform etching and / or deposition processes. In these cases, the ion suppressor can help control the concentration of ionic species in the reaction region to a level that is conducive to the process.

[0035] The showerhead 225 in combination with the ion suppressor 223 can allow the plasma present in the first plasma region 215 to avoid directly exciting the gases in the substrate processing region 233, while still allowing excited species to enter the substrate processing region 233 from the chamber plasma region 215. In this way, the chamber can be configured to prevent the plasma from contacting the etched substrate 255. This can advantageously protect the various complex structures and films patterned on the substrate; if the various complex structures and films are in direct contact with the generated plasma, they may be damaged, displaced, or otherwise warped. In addition, when the plasma is allowed to contact the substrate or approach the level of the substrate, the rate of etching of oxide species can increase. Therefore, if the exposed area of ​​the material is an oxide, this material can be further protected by keeping the plasma away from the substrate.

[0036] The processing system may further include a power supply 240 electrically coupled to the processing chamber to provide power to the faceplate 217, the ion suppressor 223, the showerhead 225, and / or the pedestal 265 to generate plasma in the first plasma region 215 or the processing region 233. Depending on the process being performed, the power supply may be configured to deliver an adjustable amount of power to the chamber. Such a configuration may allow a tunable plasma to be used in the process being performed. Unlike a remote plasma unit that typically has an on or off function, a tunable plasma may be configured to deliver a specific amount of power to the plasma region 215. This in turn may allow the development of specific plasma characteristics so that precursors may be dissociated in a specific manner to enhance the etch profile produced by these precursors.

[0037] Plasma may be ignited in the chamber plasma region 215 above the showerhead 225 or in the substrate processing region 233 below the showerhead 225. In an embodiment, the plasma formed in the substrate processing region 233 may be a DC biased plasma formed by the pedestal acting as an electrode. Plasma may exist in the chamber plasma region 215 to generate radical precursors from, for example, an inflow of a fluorine-containing precursor or other precursor. An AC voltage, typically in the radio frequency (RF) range, may be applied between a conductive top portion of the processing chamber (such as a face plate 217) and the showerhead 225 and / or the ion suppressor 223 to ignite the plasma in the chamber plasma region 215 during deposition. The RF power source may generate a high RF frequency of 13.56 MHz, but other frequencies may also be generated alone or in combination with the 13.56 MHz frequency.

[0038] Figure 2B A detailed view 253 of features affecting the distribution of process gases through the panel 217 is shown. Figure 2A and Figure 2BAs shown in FIG. 2 , the faceplate 217, the cooling plate 203, and the gas inlet assembly 205 intersect to define a gas supply region 258 into which the process gas may be delivered from the gas inlet 205. The gas may fill the gas supply region 258 and flow through the apertures 259 in the faceplate 217 to the first plasma region 215. The apertures 259 may be configured to direct the flow in a substantially unidirectional manner such that the process gas may flow into the processing region 233, but may partially or completely prevent the process gas from flowing back into the gas supply region 258 after passing through the faceplate 217.

[0039] A gas distribution assembly for use in the processing chamber portion 200, such as the showerhead 225, may be referred to as a dual channel showerhead (DCSH), and may be configured to include a plurality of showerheads. Figure 3 The described embodiments are described in further detail.A dual channel showerhead may provide an etching process that allows for separation of the etchant outside of the processing region 233 to provide limited interaction with chamber components and each other prior to delivery into the processing region.

[0040] The showerhead 225 may include an upper plate 214 and a lower plate 216. The plates may be coupled to each other to define a volume 218 between the plates. The coupling of the plates may be such as to provide a first fluid channel 219 through the upper and lower plates, and a second fluid channel 221 through the lower plate 216. The channels formed may be configured to provide fluid access from the volume 218 through the lower plate 216 only via the second fluid channel 221, and the first fluid channel 219 may be fluidically isolated from the volume 218 between the plates and the second fluid channel 221. The volume 218 may be fluidly accessible through the side of the showerhead 225.

[0041] Figure 3 is a bottom view of a showerhead 325 for use with a processing chamber according to an implementation. The showerhead 325 may correspond to Figure 2A . The through-holes 365 showing a view of the first fluid channel 219 can have a variety of shapes and configurations to control and influence the flow of precursors through the showerhead 225. The small holes 375 showing a view of the second fluid channel 221 can be substantially evenly distributed over the surface of the showerhead, even between the through-holes 365, and can help provide more uniform mixing of the precursors as they exit the showerhead than other configurations.

[0042] Figure 4 A schematic partial cross-sectional view of an exemplary semiconductor processing chamber 400 is shown in accordance with some embodiments of the present technology. Figure 4One or more of the components discussed above with respect to FIG. 2 may be included, and more details about the chamber may be shown. Chamber 400 may be used to perform semiconductor processing operations, including modification and etching as previously described. Chamber 400 may show a partial view of a processing region of a semiconductor processing system, and may not include all components (such as the additional lid stack components previously described), which should be understood to be incorporated into some embodiments of chamber 400.

[0043] As pointed out, Figure 4 A portion of a processing chamber 400 may be shown. The chamber 400 may include a showerhead 405 and a substrate support assembly 410. The showerhead 405 and the substrate support assembly 410 together with the chamber sidewall 415 may define a substrate processing region 420 in which a plasma may be generated. The substrate support may include a top disk 425, which may include one or more components embedded or disposed within the top disk. In some embodiments, the components incorporated within the top disk may not be exposed to the processing material and may be completely retained within the top disk 425. The top disk 425 may define a substrate support surface 427 and may be characterized by a height and a length. In some embodiments, the top disk may be elliptical and may be characterized by one or more radial dimensions starting from a central axis passing through the top disk. It should be understood that the top disk may be of any geometric shape and when discussing radial dimensions, the radial dimensions may define any length starting from a central location of the top disk.

[0044] The top disk 425 may be coupled to a rod 430, which may include channels for delivering and receiving electrical and / or fluid lines that may be coupled to internal components of the top disk 425 as will be discussed below. The top disk 425 may include associated channels or components to operate as an electrostatic chuck, a vacuum chuck, or any other type of chuck system. The rod 430 may be coupled to the top disk on a second surface of the top disk opposite the substrate support surface. The top disk 425 may include an electrode 435, which may be an RF electrode embedded in the top disk near the substrate support surface. The electrode 435 may be electrically coupled to a power supply 440. The power supply 440 may be configured to provide energy or voltage to the conductive disk electrode 435. This may be operated to form a biased plasma of a precursor within the processing region 420 of the semiconductor processing chamber 400. The ions formed in the processing region may be directed to the substrate located on the substrate support. This can produce modifications to the exposed film by damaging the bonded structure and facilitate removal in the subsequent etching operation described previously.

[0045] The top disk 425 may also define a recessed area 445 within the substrate support surface. The recessed area 445 may be formed at an interior area of ​​the top disk and may be configured to receive a substrate for processing. The substrate may be located within the recessed area and accommodated by an outer area 447 that may surround the substrate. In some embodiments, the height of the outer area 447 may be such that the substrate is flush with or recessed below the surface height of the substrate support surface at the outer area 447. The recessed surface may control edge effects during processing, which may improve uniformity of etching across the substrate in some embodiments. In some embodiments, an edge ring may be disposed around the periphery of the top disk and may at least partially define a recess in which the substrate may be disposed. In some embodiments, the surface of the top disk may be substantially flat and the edge ring may fully define the recess in which the substrate may be disposed.

[0046] In some embodiments, the top disk 425 and rods 430 may be insulating or dielectric materials. For example, oxides, nitrides, carbides, and other materials may be used to form the components. Exemplary materials may include ceramics including: aluminum oxide, aluminum nitride, silicon carbide, tungsten carbide, and any other metal or transition metal oxide, nitride, carbide, boride, or titanate, as well as combinations of these materials with other insulating or dielectric materials. Different grades of ceramic materials may be used to provide a composite material configured to operate within a specific temperature range, and therefore, in some embodiments, different ceramic grades of similar materials may be used for the top disk and rods.

[0047] The top disk 425 may also include an embedded heater 450 housed within the top disk. In embodiments, the heater 450 may include a resistive heater or a fluid heater. In some embodiments, the electrode 435 may operate as a heater, but by decoupling these operations, more individual control may be provided, and an extended heater coverage may be provided while limiting the area for plasma formation. Although the conductive element may be embedded within the top disk and configured to receive an electrical current (such as an AC current) to heat the top disk, the heater 450 may still include a polymer heater bonded or coupled to the top disk material. The current may be delivered through the rod 430 through a channel similar to the RF power described above. In embodiments, the heater 450 may include a plurality of heaters, and may include a first heater 452 and a second heater 454, as well as any greater number of heaters, including at least about three heaters, greater than or about four heaters, greater than or about five heaters, greater than or about six heaters, greater than or about seven heaters, greater than or about eight heaters, greater than or about nine heaters, greater than or about ten heaters, or more. Each heater may be associated with a zone of the disk, and thus an exemplary disk may include a similar number of zones as heaters or a greater number of zones.

[0048] The first heater 452 may be accommodated at a first area within the top disk, and the second heater 454 may be accommodated at a second area within the top disk. The first heater 452 may be positioned at an inner area (such as a recessed area 445) of the top disk 425, and may be positioned within or consistent with the inner area of ​​the top disk. The second heater 454 may be positioned consistent with the first heater, and in an embodiment may extend around the first heater. The second heater 454 may extend across the recessed area 445 and the outer area 447, and may be annular to extend around the first heater 452. In an embodiment, the second heater 454 may be positioned radially outside the first heater 452. A gap may be defined between the two heaters, or the heaters may extend adjacent to each other or partially overlap each other. The gap may be located between the first heater 452 and the second heater 454, and may be an annular gap radially located between the two heaters.

[0049] The first heater 452 and the second heater 454 may be operated independently of each other and are capable of adjusting the temperature of the entire top disk 425 and the substrate positioned thereon. Each heater may have a range of operating temperatures to heat the top disk and / or substrate to above or about 100° C., and each heater may be configured to heat to 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 more. The heater may be further configured to operate in any range between any two of these stated numbers, or in a smaller range within any of these ranges.

[0050] The first heater 452 and the second heater 454 may also be configured to operate within a temperature range of each other and to maintain a specific temperature across the surface of the top disk 425 or on a substrate located on the top disk 425. For example, the first heater 452 may be configured to operate to maintain an inner zone (such as the recessed area 445 or a portion of this area associated with an inner portion of the substrate) at a first temperature, and the second heater 454 may be configured to operate to maintain an outer zone or region 447 and an outer portion of the inner zone (e.g., a portion of this area associated with an outer portion of the substrate) at a second temperature that is similar to or different from the first temperature. Each temperature of the heaters or zones may be any of the temperatures described or included above, which may allow the two heaters to operate with a difference of tens or hundreds of degrees.

[0051] Additionally, in embodiments, the difference between the operating temperatures of the two heaters or the difference between the temperatures maintained by the inner zone and the outer zone may be less than 10°C. In embodiments, the temperature difference between the two heaters or the temperature difference maintained by the two zones may also be less than or about 5°C, less than or about 4°C, less than or about 3°C, less than or about 2°C, less than or about 1°C, less than or about 0.9°C, less than or about 0.8°C, less than or about 0.7°C, less than or about 0.6°C, less than or about 0.5°C, less than or about 0.4°C, less than or about 0.3°C, less than or about 0.2°C, or less than or about 0.1°C or less. In some embodiments, temperature fluctuations due to precursor flow through the substrate, interference from other chamber components, reactions or operations occurring in one zone rather than another based on a manufacturing step, and other sources of fluctuations may be controlled during operation by allowing such a slight temperature difference between the two zones. This may allow for improved uniformity across zones and across substrates being processed compared to conventional techniques.

[0052] The top disk 425 may also include a ground shield 460 embedded within the top disk, and this will be further described below. The ground shield may be one of several configurations encompassed by embodiments of the present technology, and may limit or prevent the formation of parasitic plasma in areas away from the processing region 420. The ground shield 460 may be coupled to a ground return 465 extending through the interior of the rod. The ground shield 460 may be any number of materials that may be heated to any of the temperatures discussed above, and may include a variety of conductive materials including tungsten, molybdenum, platinum, or any other conductive material that may be coupled within the top disk. For example, the conductive material of the ground shield may be selected to match the thermal expansion of the coupling material and the ceramic of the top disk (such as aluminum nitride or any of the foregoing materials). Exemplary couplings may include a variety of brazing or bonding materials (such as kovar, molybdenum, tungsten, cobalt, nickel, or any other material operable to reduce forces or stresses during heating or processing operations) that connect the ground shield to the ground return and the top disk.

[0053] In some embodiments, the heater 450 may be positioned between the electrode 435 and the grounded shield 460, although in some embodiments (such as where the heater and grounded shield are switched in position as shown), the grounded shield 460 may also be positioned between the electrode 435 and the heater 450. When the positions are switched and the heater is located below the grounded shield, the heater may be shielded, which may improve performance. However, such a switch may position the heater further from the substrate, which may cause problems for controlled heating. In addition, a certain distance may be maintained between the electrode and the grounded shield to ensure that power extends to the plasma and is not excessively siphoned by the grounded shield, which may increase the thickness of the disk in this configuration and may further cause problems for controlled heating.

[0054] In some embodiments, the top disk 425 may optionally include a ground impedance electrode 470 embedded within the top disk, and in some embodiments, the top disk 425 may include multiple ground impedance electrodes. The ground impedance electrode 470 may be coupled to a ground source that is separate from the ground shield 460. The ground impedance electrode 470 may be coupled to a ground loop through a variable capacitor, which may allow adjustment of the plasma sheath. In some embodiments, the ground impedance electrode may be incorporated around the outer region 447 of the top disk and may be a ring electrode as shown. As previously described, edge effects may occur in plasma generation due to the nature of the plasma sheath at the edge. For example, if the sheath is curved around the edge of the substrate, the direction of ion bombardment may be affected, which may direct the ions to the substrate in a direction less than the perpendicular trajectory and this may affect the uniformity of operation. By adjusting the capacitor on the loop of the ground grid, different potentials may be extended on the impedance electrode, which may allow the sheath potential at the edge to be controlled and this may improve the uniformity of operation.

[0055] Figure 5 A schematic partial cross-sectional view of an exemplary substrate support assembly 500 according to an embodiment of the present technology is shown. The substrate support assembly 500 can be similar to the substrate support or base 265 discussed previously, and can include some or all of the features discussed above with respect to the structure. The substrate support assembly 500 can also be similar to the substrate support assembly 410, and can include some or all of the components or features described above. As shown, the substrate support assembly 500 includes a top disk 505 and a rod 510. As previously described, both the top disk 505 and the rod 510 can be or include ceramic or dielectric materials.

[0056] The top disk 505 may define a substrate support surface 506 and may include an inner region 507 and an outer region 509. The inner region 507 may be recessed from the outer region 509 and may be configured to support a substrate within the recess, as previously described. One or more components may be embedded within the top disk 505. An electrode 515, which may be an RF electrode, may be positioned proximate to or adjacent to the substrate support surface 506. In some embodiments, the electrode 515 may not extend radially outward beyond the inner region 507, although in some embodiments, the electrode may extend at least partially into the outer region 509. The electrode 515 may be coupled to an RF source 520, which may extend through the rod 510. For example, an RF rod 521 may extend through the inner channel 522 and connect to the electrode 515, which may be used to generate a bias plasma in a processing region above the substrate support surface 506. The top disk 505 may also include a heater 525, which may include a first internal heater 527 and a second external heater 529 as previously described, and the heater 525 may heat the top disk and / or the substrate as described above. It should be understood that, as previously described, any number of heaters may be included, and in some embodiments may include at least about 2, at least about 4, at least about 6, at least about 8, at least about 10, or more heaters and associated zones.

[0057] The top disk 505 may also include a ground shield 530 embedded within the top disk as previously described. In some embodiments, the ground shield 530 may be characterized by a single piece or a multi-piece design. The ground shield 530 may include or be characterized by an inner region 532 and an outer region 534. The inner region 532 may extend across the top disk 505 and may extend radially through the top disk from the central axis. In some embodiments, the inner region 532 may extend beyond the radial edge of the electrode 515 and may extend into the outer region 509 of the top disk 505. The outer region 534 may be disposed radially outward from the inner region 532 and may extend vertically through the height of the top disk 505. For example, in some embodiments shown, the outer region 534 may extend substantially or substantially perpendicular to the inner region 532 and may extend partially or substantially along the height of the top disk. Thus, the ground shield 530 may resemble a dish-shaped profile having a raised outer surface surrounding a central recessed region. The ground shield 530 may be a mesh within a top disk, a coil, a solid base, or any number of other form factors.

[0058] A central aperture may be formed in the inner region 532, which may allow the electrode RF rod 521 to extend through the ground shield without being in electrical contact with the shield. The ground shield 530 may be coupled to the ground 535 via a ground loop 537 extending through the inner passage 522 and through the rod 510. For example, the ground loop 537 may extend coaxially with the RF rod 521 through the inner passage 522 and remain electrically isolated from the RF rod 521. In some embodiments, an insulator (such as a cylindrical insulator) may be positioned between the RF rod 521 and the ground loop 537. Since the ground shield 530 may be electrically coupled to the ground, this configuration may keep the electrode and the ground shield electrically isolated from each other.

[0059] Figure 6 A schematic partial cross-sectional view of an exemplary substrate support assembly 600 according to some embodiments of the present technology is shown. The substrate support assembly 600 may be similar to the substrate support or base 265 previously discussed, and may include some or all of the features discussed above with respect to the structure. The substrate support assembly 600 may also be similar to the substrate support assembly 410 and the substrate support assembly 500, and may include some or all of the components or features described above. The substrate support assembly 600 may include additional embedded ground shield configurations covered by the present technology. As shown, the substrate support assembly 600 includes a top disk 605 and a rod 610. As previously described, both the top disk 605 and the rod 610 may be or include ceramic or dielectric materials.

[0060] The top disk 605 may define a substrate support surface 606 and may include an inner region 607 and an outer region 609. The inner region 607 may be recessed from the outer region 609 and may be configured to support a substrate within the recess, as previously described. One or more components may be embedded within the top disk 605. An electrode 615, which may be an RF electrode, may be positioned proximate or adjacent to the substrate support surface 606. In some embodiments, the electrode 615 may not extend radially outward beyond the inner region 607, although in some embodiments, the electrode may extend at least partially into the outer region 609. The electrode 615 may be coupled to an RF source 620, which may extend through the rod 610. For example, an RF rod 621 may extend through the inner channel 622 and connect to the electrode 615, which may be used to generate a bias plasma in a processing region above the substrate support surface 606. The top disk 605 may also include a heater 625, which may include a first inner heater 627 and a second outer heater 629 as previously described, and the heater 625 may heat the top disk and / or the substrate as described above.

[0061] The top disk 605 may also include a ground shield 630 embedded within the top disk as previously described. In some embodiments, the ground shield 630 may be characterized by a single-piece or multi-piece design. The ground shield 630 may include or be characterized by an inner region 632 and an outer region 634. The inner region 632 may extend across the top disk 605 and may extend radially from the center axis through the top disk, thereby forming a base of the ground shield. In some embodiments, the inner region 632 may extend beyond the radial edge of the electrode 615 and may extend into the outer region 609 of the top disk 605. The outer region 634 may be disposed radially outward from the inner region 632 and may extend vertically through the height of the top disk 605. For example, in some embodiments shown, the outer region 634 may extend substantially or substantially perpendicular to the inner region 632 and may extend partially or substantially along the height of the top disk. The outer region 634 may be different from the outer region 534 described above. Although Figure 5 The ground shield may resemble a dish or platter profile, but the ground shield 630 may have connected components.

[0062] The outer region 634 of the ground shield 630 may include one or more annular members or rings 640 distributed vertically across the height of the top disk 605. For example, the ground shield 630 may include at least one intermediate ring 640 positioned vertically between the ground shield base and the electrode 615. The ground shield 630 may also include a plurality of rings that are vertically disposed or offset from one another across the height of the top disk, and the plurality of rings may include at least 2 rings, greater than or about 3 rings, greater than or about 4 rings, greater than or about 6 rings, greater than or about 8 rings, greater than or about 10 rings, greater than or about 15 rings, or more, depending on the height of the top disk and the spacing between the rings. For example, the spacing between the rings may affect the amount of shielding of the emission.

[0063] The frequency of RF delivery may also affect the amount of spacing between the rings. For example, in the case where the plasma can be generated at a lower frequency operation (such as about 13.56 MHz or lower), more space can be accommodated between the rings, while under higher frequency operation (such as 60 MHz), smaller spacing can be used to limit the emission through the shield. Therefore, when the operating conditions of the chamber are understood, the spacing between the rings and / or the number of rings can be used to adapt to the application. Therefore, as the frequency in the application increases, the number of rings can be increased and / or the spacing between the rings can be reduced. In some embodiments, the spacing between any two adjacent rings and / or bases can be less than or about 1 cm, and can be less than or about 9 mm, less than or about 8 mm, less than or about 7 mm, less than about 6 mm, less than or about 5 mm, less than or about 4 mm, less than or about 3 mm, less than or about 2 mm, less than or about 1 mm or less.

[0064] One or more rings 640 may be electrically coupled to the base via one or more vertical posts 645. For example, at least one post may electrically couple one or more rings to the base to provide a ground path. In some embodiments, the top disk may include at least 2 vertical posts, and in some embodiments may include greater than or about 3 posts, greater than or about 4 posts, greater than or about 6 posts, greater than or about 8 posts, greater than or about 10 posts, greater than or about 12 posts, greater than or about 14 posts, greater than or about 16 posts, greater than or about 18 posts, greater than or about 20 posts, or more posts. The posts may be equally spaced around the top disk, or may be positioned in multiple areas around the top disk, as well as any other distribution. In addition, when multiple rings are included, in some embodiments, the sizes of the rings may be similar or different. For example, a ring may have a different ring thickness or length than other rings, which may further accommodate different plasma frequencies, where increased surface area or a single ring may allow for increased spacing between rings, or a reduction in the number of rings to provide a specific effect.

[0065] Similar to the substrate support assembly 500, a central aperture or through hole may be formed in the inner region 632 of the ground shield, which may allow the electrode RF rod 621 to extend through the ground shield without electrically contacting the shield. The ground shield 630 may be coupled to the ground 635 via a ground loop 637 extending through the inner passage 622 and through the rod 610. For example, the ground loop 637 may extend coaxially with the RF rod 621 through the inner passage 622 and remain electrically isolated from the RF rod 621. Because the ground shield 630 may be electrically coupled to the ground, this configuration may keep the electrode and the ground shield electrically isolated from each other. By utilizing an embedded ground shield according to some embodiments of the present technology, processing may be performed at higher temperatures without the risk of chemical corrosion, erosion, or melting of the components that make up the shield.

[0066] In the foregoing description, for the purpose of explanation, many details have been 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 may be implemented without some of these details or with additional details.

[0067] Several embodiments have been disclosed, and those skilled in the art will recognize that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the embodiments. In addition, in order to avoid unnecessary confusion of the present technology, many well-known processes and elements are not described. Therefore, the above description should not be considered to limit the scope of the present technology.

[0068] In the case of providing a range of values, it is understood that unless the context clearly indicates otherwise, each intermediate value between the upper and lower limits of the range to the minimum fraction of the lower limit unit is also specifically disclosed. Any narrower range between any clarified value or unclarified intermediate value in the clarified range and any other clarified value or intermediate value in the clarified range are covered. Those upper and lower limits of smaller ranges may be independently included in the described range or excluded from the described range, and wherein in the described smaller range, including any limit, not including any limit, or including each range in two limits is also covered in the present technology, subject to any specifically excluded limit in the clarified range. In the case where the clarified range includes one or two of the limits, the scope excluding any one or both of these limits is also covered in the present technology.

[0069] As used herein 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 ring" includes a plurality of such rings and reference to "a precursor" includes reference to one or more precursors and equivalents thereof known to those skilled in the art, and so forth.

[0070] Furthermore, when used in this specification and the following claims, the terms “comprise,” “comprising,” “contain,” “containing,” “include,” and “including” are intended to specify the presence of stated features, integers, components, or operations, but the terms do not exclude the presence or addition of one or more other features, integers, components, operations, acts, or groups.

Claims

1. A substrate support assembly, comprising: a top disk defining a substrate support surface, wherein the top disk is characterized by a height; an RF electrode embedded in the top disk near the substrate supporting surface; a heater embedded in the top disk; a ground shield embedded within the top disk, wherein the ground shield includes a base extending radially through the top disk, wherein the ground shield further includes an intermediate ring positioned vertically between the ground shield base and the RF electrode, wherein the intermediate ring is electrically coupled to the base; as well as a conductive post extending vertically within the top disk and electrically coupling the middle ring of the ground shield with the base of the ground shield, Wherein the ground shield is further characterized by an outer region, the conductive posts and the intermediate ring are positioned at the outer region of the ground shield relative to the RF electrode.

2. The substrate support assembly of claim 1, wherein the outer region extends perpendicular to the pedestal, and wherein the outer region of the ground shield extends vertically at least partially through the height of the top disk.

3. The substrate support assembly of claim 1, wherein the top disk defines a recess within the substrate supporting surface, the recess being configured to receive a substrate for processing.

4. The substrate support assembly of claim 1, wherein the top disk comprises a ceramic material.

5. The substrate support assembly of claim 1 , wherein the heater is positioned within the top disk at a location between the RF electrode and the grounded shield, and wherein the heater is configured to heat a substrate supported by the top disk to a temperature greater than 300° C.

6. The substrate support assembly of claim 5, wherein the heater comprises a first heater and a second heater, wherein the second heater is controllable independently of the first heater, and wherein the second heater extends around an outer edge of the first heater.

7. The substrate support assembly of claim 1, further comprising: a rod coupled to the top disk on a second surface of the top disk opposite the substrate supporting surface, wherein the rod defines an interior passage through which an RF rod extends and is coupled to the RF electrode; and A ground loop extends through the internal passage coaxially with the RF rod.

8. The substrate support assembly of claim 1, further comprising a grounded impedance electrode disposed within the top disk proximate the substrate supporting surface.

9. A substrate support assembly comprising: a top disk defining a substrate support surface and characterized by a height; a rod coupled to the top disk on a second surface of the top disk opposite the substrate supporting surface; an RF electrode embedded in the top disk near the substrate supporting surface; a heater embedded in the top disk; a ground shield embedded within the top disk, wherein the ground shield includes a base extending radially through the top disk, wherein the ground shield further includes an intermediate ring positioned vertically between the ground shield base and the RF electrode, wherein the intermediate ring is electrically coupled to the base; as well as a conductive post extending vertically within the top disk and electrically coupling the middle ring of the ground shield with the base of the ground shield, Wherein the ground shield is further characterized by an outer region, the conductive posts and the intermediate ring are positioned at the outer region of the ground shield relative to the RF electrode.

10. The substrate support assembly of claim 9, wherein the top disk defines a recess within the substrate supporting surface, the recess being configured to receive a substrate for processing.

11. The substrate support assembly of claim 9, wherein the top disk and the rods comprise a ceramic material.

12. The substrate support assembly of claim 9, wherein the heater is positioned within the top disk at a location between the RF electrode and the ground shield, wherein the heater is configured to heat a substrate supported by the top disk to a temperature greater than 300° C., wherein the heater comprises a first heater and a second heater, wherein the second heater is controllable independently of the first heater, and wherein the second heater extends around an outer edge of the first heater.

13. The substrate support assembly of claim 9, further comprising a ground impedance electrode disposed within the top disk proximate the substrate supporting surface, wherein the ground impedance electrode is coupled to ground along a ground path separate from the ground shield.

14. The substrate support assembly of claim 9, wherein the intermediate ring comprises a plurality of intermediate rings vertically offset from one another within the top disk, and wherein each intermediate ring of the plurality of intermediate rings is positioned within 1 cm of an adjacent ring within the top disk.

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