Semiconductor substrate support having an internal channel - Patent Application 20070122997

Abstract

An exemplary substrate support assembly may include an electrostatic chuck body defining a substrate support surface. The support assembly may include a support stem coupled to the electrostatic chuck body. The support assembly may include an electrode embedded within the electrostatic chuck body proximate the substrate support surface. The support assembly may include a ground electrode embedded within the electrostatic chuck body. The support assembly may include one or more channels formed between the electrode within the electrostatic chuck body and the ground electrode.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of and priority to U.S. patent application Ser. No. 16 / 844,134, filed Apr. 9, 2020, entitled "SEMICONDUCTOR SUBSTRATE SUPPORT WITH INTERNAL CHANNELS," which is incorporated herein by reference in its entirety.

[0002]

[0002] The present technology relates to semiconductor manufacturing components and apparatus. More particularly, the present technology relates to substrate support assemblies and other semiconductor processing equipment. [Background technology]

[0003]

[0003] Integrated circuits are made possible by processes that fabricate intricately patterned layers of material on substrate surfaces. Fabricating patterned materials on substrates requires controlled methods for forming and removing material. Substrate supports can play a key role in semiconductor processing by providing temperature control of the substrate and aspects related to embedded electrodes utilized in plasma formation within the processing chamber. Adjusting the many relevant aspects of semiconductor substrate supports can involve competing properties and materials. As manufacturing results become increasingly sensitive to processing conditions, substrate support aspects can significantly impact many processing characteristics.

[0004]

[0004] Therefore, there is a need for improved systems and methods that can be used to manufacture high quality devices and structures. These and other needs are addressed by the present technique. Summary of the Invention

[0005] An exemplary substrate support assembly may include an electrostatic chuck body defining a substrate support surface. The support assembly may include a support stem coupled to the electrostatic chuck body. The support assembly may include an electrode embedded within the electrostatic chuck body proximate the substrate support surface. The support assembly may include a ground electrode embedded within the electrostatic chuck body. The support assembly may include one or more channels formed between the electrode within the electrostatic chuck body and the ground electrode.

[0006] In some embodiments, the electrostatic chuck body may be a monolithic body of ceramic material incorporating an electrode, a ground electrode, and one or more channels. The assembly may include a heater embedded between the electrode and the ground electrode within the electrostatic chuck body. The one or more channels may include a plurality of channels. A first channel of the plurality of channels may be formed between the electrode and the heater within the electrostatic chuck body. A second channel of the plurality of channels may be formed between the ground electrode and the heater within the electrostatic chuck body. A third channel of the plurality of channels may be formed between the electrode and the heater within the electrostatic chuck body vertically offset from the first channel of the plurality of channels within the electrostatic chuck body. The first channels may include a first set of interconnected channels. The channels may include a plurality of first annular channels distributed across a first plane of the electrostatic chuck body. The channels may include a plurality of first channel interconnectors distributed radially between each first annular channel of the plurality of first annular channels.

[0007] The third channel may include a set of second interconnected channels. The channel may include a plurality of second annular channels distributed across a second plane of the electrostatic chuck body. The second plane of the electrostatic chuck body may be vertically offset from the first plane of the electrostatic chuck body. The channel may include a plurality of second channel interconnectors distributed radially between each second annular channel of the plurality of second annular channels. The plurality of second annular channels may be radially offset from the plurality of first annular channels. The plurality of second channel interconnectors may be azimuthally offset from the plurality of first channel interconnectors. The second channel may include a set of third interconnected channels. The channel may include a plurality of third annular channels distributed across a third plane of the electrostatic chuck body. The third plane of the electrostatic chuck body may be vertically offset from the first plane of the electrostatic chuck body and the second plane of the electrostatic chuck body. The channel may include a plurality of third channel interconnectors radially distributed among each third annular channel of the plurality of third annular channels. Each channel of the plurality of third annular channels may be vertically aligned with an associated channel of the plurality of first annular channels. The plurality of second channel interconnectors may be azimuthally aligned with the plurality of first channel interconnectors. The assembly may include a fourth channel formed in a third plane of the electrostatic chuck body. The channel may be configured to seat a thermocouple extending through a support stem coupled to the electrostatic chuck body.

[0008] Some embodiments of the present technique may include a substrate support assembly. The assembly may include an electrostatic chuck body defining a substrate support surface. The assembly may include a support stem coupled to the electrostatic chuck body. The assembly may include an electrode embedded within the electrostatic chuck body proximate the substrate support surface. The assembly may include a ground electrode embedded within the electrostatic chuck body. The assembly may include a first set of interconnected channels formed between the electrode within the electrostatic chuck body and the ground electrode. The assembly may include a second set of interconnected channels formed between the electrode within the electrostatic chuck body and the ground electrode. The second set of interconnected channels may be radially offset from the first set of interconnected channels. The first set of interconnected channels may be maintained at least 5 mm from a radial edge of the electrostatic chuck body. The first set of interconnected channels and the second set of interconnected channels may be maintained at atmospheric pressure.

[0009] In some embodiments, the effective capacitance between the electrode and the ground electrode within the electrostatic chuck body may be about 1000 pF or less. The electrostatic chuck body may be characterized by a volume fraction of air of about 10% or greater. The assembly may include a heater positioned between the electrode and the ground electrode. The assembly may also include a third set of interconnected channels formed between the heater and the ground electrode within the electrostatic chuck body.

[0010] Some embodiments of the present technique may include a substrate support assembly. The assembly may include an electrostatic chuck body defining a substrate support surface. The assembly may include a support stem coupled to the electrostatic chuck body. The assembly may include an electrode embedded within the electrostatic chuck body proximate the substrate support surface. The assembly may include a ground electrode embedded within the electrostatic chuck body. The assembly may include a heater embedded between the electrode and the ground electrode within the electrostatic chuck body. The assembly may include a first set of interconnected channels formed between the electrode and the heater within the electrostatic chuck body. The assembly may include a second set of interconnected channels formed between the first set of interconnected channels within the electrostatic chuck body and the heater. The assembly may include a third set of interconnected channels formed between the heater within the electrostatic chuck body and the ground electrode.

[0011] The above techniques may offer numerous advantages over conventional systems and techniques. For example, the incorporation of channels into the substrate support may improve the effective capacitance between buried electrodes. Furthermore, tuning the channels may enable the distance between the hot and ground electrodes to be reduced while limiting the effective capacitance. These and other embodiments, along with their many advantages and features, are described in more detail in connection with the following description and accompanying figures.

[0012] A further understanding of the nature and advantages of the disclosed technology may be realized by reference to the remaining portions of the specification and the drawings. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic cross-sectional view illustrating an exemplary plasma system according to some embodiments of the present technique; [Figure 2] 1 is a schematic partial cross-sectional view of an exemplary substrate support assembly according to some embodiments of the present technique; [Figure 3]1 is a schematic plan view of a portion of an exemplary substrate support assembly in accordance with some embodiments of the present technique; [Figure 4] 1 is a schematic plan view of a portion of an exemplary substrate support assembly in accordance with some embodiments of the present technique; [Figure 5] 1 is a schematic plan view of a portion of an exemplary substrate support assembly in accordance with some embodiments of the present technique; [Figure 6] 1 is a schematic partial cross-sectional view of an exemplary substrate support assembly according to some embodiments of the present technique; [Figure 7] FIG. 1 is a schematic plan view of a portion of an exemplary electrostatic chuck body in accordance with some embodiments of the present technique. DETAILED DESCRIPTION OF THE INVENTION

[0014]

[0020] Some of the figures are included as schematic diagrams. It should be understood that schematic diagrams are for illustrative purposes and should not be considered to scale unless the scale is explicitly stated. Furthermore, the figures are provided to aid in understanding and may not include all aspects or information compared to realistic representations and may include exaggerated material for illustrative purposes.

[0015]

[0021] In the accompanying figures, similar components and / or features may be labeled with the same reference label. Furthermore, various components of the same type may be distinguished by following the reference label with a letter that distinguishes between the similar components. When only a first reference label is used herein, the description applies to any one of the similar components having the same first reference label, regardless of the letter.

[0016]

[0022] The plasma deposition process may apply a voltage to one or more constituent precursors to promote film formation on the substrate. An electrostatic chuck may be used to provide a clamping action on the substrate, maintaining overall substrate planarity and contact between the substrate and the substrate support. The substrate support may perform multiple functions during plasma processing. For example, in addition to chucking the wafer to the substrate support, the substrate support may include one or more embedded heaters to control the temperature of the substrate during processing. Furthermore, the substrate support may act as one of the electrodes of a capacitively coupled plasma generated within the substrate processing region of the semiconductor processing chamber.

[0017]

[0023] The electrode in the substrate support and the opposing faceplate or showerhead can act as two opposing capacitively coupled electrodes during plasma processing. This can generate a plasma between the components, ionizing delivered precursors and generating reactants that can deposit material on the substrate. In some embodiments, the chamber body is grounded and can act as a ground path, but this ground path can cause problems during processing. The ground path from the hot electrode in the pedestal to the chamber wall may not be symmetrical with the gap region around and below the substrate support, creating areas of higher electric field distribution and potentially igniting stray plasma in the region around the substrate support. To ameliorate the problems associated with asymmetric grounding, many substrate supports include an additional ground electrode within the substrate support itself. The ground electrode in the substrate support may be separated from the plasma-generating electrode in the platen portion of the substrate support or from the electrostatic chuck body. Because many substrate supports are made of ceramic or dielectric materials, shorting between these electrodes may not occur, but electrical loss from the hot electrode to the ground electrode through the dielectric may occur.

[0018]

[0024] While improving the symmetry of the ground path and incorporating a ground electrode within the electrostatic chuck body can reduce stray plasma issues, many conventional techniques must accept electrical losses due to the incorporation of a ground electrode within the substrate support. One solution to reducing these losses may involve increasing the thickness of the dielectric material, thereby increasing the corresponding distance between the hot electrode and the ground electrode and reducing capacitive losses between these two components. However, due to space constraints within the processing chamber, many substrate supports are vertically constrained, which may limit the ability to sufficiently increase the thickness of the chuck body. This technique overcomes these issues by manipulating the electrical properties of the ground plate ceramic. By including an air or fluid space within the substrate support, the effective capacitance between the hot electrode and the ground electrode can be reduced while maintaining a specific thickness of the substrate support.

[0019]

[0025] While the remainder of the disclosure periodically identifies particular deposition processes and chambers that use the disclosed technology, it will be readily understood that the systems and methods are equally applicable to other deposition, etch, and cleaning chambers and processes that may be performed in the described chambers. Accordingly, the present technology should not be considered limited to use with only these particular deposition processes or chambers. This disclosure describes one possible chamber that may include a substrate support assembly according to an embodiment of the present technology, before describing additional modifications and adjustments to this system according to an embodiment of the present technology.

[0020]

[0026] FIG. 1 is a cross-sectional view illustrating an exemplary processing chamber 100 according to some embodiments of the present technique. The diagram may generally illustrate a system incorporating one or more aspects of the present technique and / or may be specifically configured to perform one or more operations according to embodiments of the present technique. Additional details of the chamber 100 or the method performed may be further described below. While the chamber 100 may be used to form a film layer according to some embodiments of the present technique, it should be understood that the method may similarly be performed in any chamber in which film formation may occur. The processing chamber 100 may include a chamber body 102, a substrate support 104 disposed within the chamber body 102, and a lid assembly 106 coupled to the chamber body 102 and enclosing the substrate support 104 within a processing region 120. A substrate 103 may be provided to the processing region 120 through an opening 126, which may be conventionally sealed for processing using a slit valve or door. The substrate 103 may rest on a surface 105 of the substrate support during processing. The substrate support 104 may be rotatable along an axis 147 about which the shaft 144 of the substrate support 104 may lie, as indicated by arrow 145. Alternatively, the substrate support 104 may be elevated to rotate as needed during the deposition process.

[0021]

[0027] A plasma profile modulator 111 may be disposed in the processing chamber 100 to control plasma distribution across a substrate 103 disposed on a substrate support 104. The plasma profile modulator 111 may include a first electrode 108 disposed adjacent to the chamber body 102 and may separate the chamber body 102 from other components of the lid assembly 106. The first electrode 108 may be part of the lid assembly 106 or may be a separate sidewall electrode. The first electrode 108 may be an annular or ring-shaped member, such as a ring electrode. The first electrode 108 may be a continuous loop around the processing chamber 100 surrounding the processing region 120, or may be discontinuous at selected locations as desired. The first electrode 108 may also be a perforated electrode, such as a perforated ring or mesh electrode, or a plate electrode, such as a secondary gas distributor.

[0022]

[0028] One or more isolators 110 a, 110 b, which may be a dielectric material such as a ceramic or a metal oxide, e.g., aluminum oxide and / or aluminum nitride, may contact the first electrode 108 and electrically and thermally isolate the first electrode 108 from the gas distributor 112 and from the chamber body 102. The gas distributor 112 may define an aperture 118 for distributing process precursors into the processing region 120. The gas distributor 112 may be coupled to a first power source 142, such as an RF generator, an RF power source, a DC power source, a pulsed DC power source, a pulsed RF power source, or any other power source that may be coupled to a processing chamber. In some embodiments, the first power source 142 may be an RF power source.

[0023]

[0029] The gas distributor 112 may be a conductive gas distributor or a non-conductive gas distributor. The gas distributor 112 may also be formed from conductive and non-conductive components. For example, the body of the gas distributor 112 may be conductive, while the faceplate of the gas distributor 112 may be non-conductive. The gas distributor 112 may be powered by, for example, the first power supply 142 shown in FIG. 1 , or the gas distributor 112 may be coupled to ground in some embodiments.

[0024]

[0030] The first electrode 108 may be coupled to a first tuned circuit 128 that may control the ground path of the processing chamber 100. The first tuned circuit 128 may include a first electronic sensor 130 and a first electronic controller 134. The first electronic controller 134 may be or include a variable capacitor or other circuit element. The first tuned circuit 128 may be or include one or more inductors 132. The first tuned circuit 128 may be any circuit that allows for a variable or controllable impedance under plasma conditions present in the processing region 120 during processing. In some illustrated embodiments, the first tuned circuit 128 may include a first circuit leg and a second circuit leg coupled in parallel between ground and the first electronic sensor 130. The first circuit leg may include a first inductor 132A. The second circuit leg may include a second inductor 132B coupled in series to the first electronic controller 134. The second inductor 132B may be disposed between the first electronic controller 134 and a node connecting both the first and second circuit legs to the first electronic sensor 130. The first electronic sensor 130 may be a voltage or current sensor and may be coupled to the first electronic controller 134 to provide some degree of closed-loop control of the plasma conditions within the processing region 120.

[0025]

[0031] The second electrode 122 may be coupled to the substrate support 104. The second electrode 122 may be embedded within the substrate support 104 or may be coupled to a surface of the substrate support 104. The second electrode 122 may be a plate, perforated plate, mesh, wire screen, or any other distributed arrangement of conductive elements. The second electrode 122 may be a tuning electrode and may be coupled to a second tuning circuit 136 by a conduit 146, such as a cable having a selected resistance, e.g., 50 ohms, disposed on a shaft 144 of the substrate support 104. The second tuning circuit 136 may include a second electronic sensor 138 and a second electronic controller 140, which may be a second variable capacitor. The second electronic sensor 138 may be a voltage or current sensor and may be coupled to the second electronic controller 140 to provide further control over the plasma conditions in the processing region 120.

[0026]

[0032] A third electrode 124, which may be a bias electrode and / or an electrostatic chucking electrode, may be coupled to the substrate support 104. The third electrode may be coupled to a second power source 150 through a filter 148, which may be an impedance matching circuit. The second power source 150 may be DC power, pulsed DC power, RF bias power, a pulsed RF source or bias power, or a combination thereof or other power source. In some embodiments, the second power source 150 may be RF bias power.

[0027]

[0033] The lid assembly 106 and substrate support 104 of FIG. 1 can be used with any processing chamber for plasma or thermal processing. In operation, the processing chamber 100 can provide real-time control of plasma conditions in the processing region 120. The substrate 103 can be placed on the substrate support 104, and process gases can be flowed through the lid assembly 106 using the inlet 114 according to any desired flow scheme. The gases can exit the processing chamber 100 through the outlet 152. Power can be coupled to the gas distributor 112 to establish a plasma in the processing region 120. An electrical bias can be applied to the substrate using the third electrode 124, in some embodiments.

[0028]

[0034] When a voltage is applied to the plasma in the processing region 120, a potential difference may be established between the plasma and the first electrode 108. A potential difference may also be established between the plasma and the second electrode 122. Electronic controllers 134, 140 may then be used to adjust the mobility of the ground paths represented by the two tuned circuits 128 and 136. Set points may be delivered to the first tuned circuit 128 and the second tuned circuit 136 to obtain independent control of the deposition rate and center-to-edge plasma density uniformity. In embodiments where both electronic controllers may be variable capacitors, electronic sensors may independently adjust the variable capacitors to maximize the deposition rate and minimize thickness non-uniformity.

[0029]

[0035] The tuning circuits 128, 136 may each have a variable impedance that can be adjusted using the respective electronic controllers 134, 140. If the electronic controllers 134, 140 are variable capacitors, the capacitance range of each variable capacitor and the inductance of the first inductor 132A and the second inductor 132B may be selected to provide an impedance range. This range may depend on the frequency and voltage characteristics of the plasma and may have a minimum value in the capacitance range of each variable capacitor. Thus, when the capacitance of the first electronic controller 134 is minimum or maximum, the impedance of the first tuning circuit 128 may be high, resulting in a plasma shape with minimal aerial or lateral coverage over the substrate support. When the capacitance of the first electronic controller 134 approaches a value that minimizes the impedance of the first tuning circuit 128, the aerial coverage of the plasma may be maximized, effectively covering the entire working area of the substrate support 104. If the capacitance of the first electronic controller 134 deviates from the minimum impedance setting, the plasma shape will shrink from the chamber walls and the air coverage of the substrate support may decrease. The second electronic controller 140 has a similar effect; as the capacitance of the second electronic controller 140 can be changed, the air coverage of the plasma above the substrate support may increase and decrease.

[0030]

[0036] Electronic sensors 130, 138 can be used to tune the respective circuits 128, 136 in a closed loop. Depending on the type of sensor used, a current or voltage set point can be installed in each sensor, which can include control software that determines adjustments to the respective electronic controllers 134, 140 to minimize deviations from the set point. As a result, the plasma shape can be selected and dynamically controlled during processing. While the above description is based on electronic controllers 134, 140 being variable capacitors, it should be understood that any electronic component with adjustable characteristics can be used to provide tuning circuits 128 and 136 with adjustable impedance.

[0031]

[0037] FIG. 2 is a schematic, partial cross-sectional view illustrating an exemplary substrate support 200 according to some embodiments of the present technology. For example, the substrate support 200 may illustrate a portion of the substrate support 104 described above, may include any aspect of that support assembly, and may illustrate additional details of that support assembly. The substrate support 200 may illustrate a simplified cross-section of a support structure that may include numerous other components or aspects as previously described or that may be included in a substrate support. It should be understood that the substrate support 200 is not illustrated to any particular scale and is included merely to illustrate aspects of the present technology. The substrate support 200 may be included within the aforementioned chamber, as well as any other processing chamber or other component positioned within a processing chamber that may define a substrate processing region, such as with one or more walls of a chamber body. The substrate support 200 may illustrate a partial view of components and couplings within an exemplary semiconductor processing system and may not include all of the components, such as the aforementioned chamber components and features, that are understood to be incorporated in some embodiments around and with the substrate support 200.

[0032]

[0038] The substrate support 200 may include multiple components bonded, welded, bonded, sintered, molded, or otherwise joined together. The substrate support assembly may include an electrostatic chuck body 205, which may include one or more components embedded or disposed within the body. Components embedded within the top puck may not be exposed to process materials in some embodiments and may be retained entirely within the chuck body 205. The electrostatic chuck body 205 may define a substrate support surface 207 and may 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 may be elliptical and characterized by one or more radial dimensions from a central axis through the chuck body. It should be understood that the top puck may be any geometry, and when discussing radial dimensions, they may define any length from a central location of the chuck body.

[0033]

[0039] The electrostatic chuck body 205 may be coupled to a stem 210, which may support the chuck body and may include channels for electrical and / or fluid lines that may be coupled to internal components of the chuck body 205. While the chuck body 205 may include associated channels or components for operation as an electrostatic chuck, in some embodiments, the assembly may operate as or include components for a vacuum chuck or any other type of chucking system. The stem 210 may be coupled to the chuck body at a second surface of the chuck body opposite the substrate support surface. The electrostatic chuck body 205 may include an electrode 215 embedded within the chuck body proximate the substrate support surface. The electrode 215 may be electrically coupled to a power source to operate as a plasma-generating electrode alone or in conjunction with another component, such as a faceplate or other chamber component, for generating a capacitively coupled plasma above the wafer. The power source may be configured to provide energy or voltage to the conductive chuck electrode 215, which in some embodiments may also operate as a chucking electrode.

[0034]

[0040] In some embodiments, the electrostatic chuck body 205 and / or stem 210 may be an insulating or dielectric material. For example, various polymeric materials, including polystyrene or other materials containing cross-linked materials, as well as 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 achieve a composite material configured to operate over a specific temperature range; therefore, in some embodiments, similar materials with different ceramic grades may be used for the top puck and stem. In some embodiments, dopants may be incorporated to adjust the electrical or other properties of the components. Exemplary dopant materials may 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.

[0035]

[0041] The chuck body may include a ground electrode 220 that may be positioned proximate the backside of the chuck body, for example, proximate the surface to which the stem is bonded. Additionally, a heater 225 may be incorporated within the chuck body, such as between the electrode 215 and the ground electrode 220. An electrical connection between the heater and the electrode may extend through the stem and substrate support, electrically coupling the component to a power source.

[0036]

[0042] In some embodiments, the electrostatic chuck body may also include or define one or more channels between the electrode 215 and the ground electrode 220 within the electrostatic chuck body. As previously explained, electrical losses can occur from the electrode 215 through the electrostatic chuck body 205 to the ground electrode 220. In some embodiments, the thickness of the chuck body may be fixed, and therefore, reducing electrical losses by increasing the distance between the electrodes may not be feasible. Therefore, in some embodiments, the electrical properties of the chuck body may be modified by incorporating a gap that may contain air or some other fluid or gas that is pumped into the channel.

[0037]

[0043] Increasing the thickness of the chuck body to further separate the electrodes, as well as increasing the air pockets or porosity, can reduce the effective capacitance between the two electrodes within the chuck body. However, a sufficient volume of air or fluid may be contained to effectively reduce capacitance. However, increasing the porosity of the entire substrate support may result in leakage. For example, the substrate support may be contained within a processing chamber that can operate under vacuum during semiconductor processing. Channels formed in the stem and upper puck for supplying fluids or making electrical connections may be maintained at atmospheric pressure. If the chuck body is sufficiently porous, the pressure difference between atmospheric components and the vacuum conditions within the chamber may cause air to leak through the porous body into the processing chamber. As a result, simply increasing the porosity of the puck body may not be enough to contain a sufficient volume of air to effectively reduce capacitance without impairing the operation of the substrate support for processing.

[0038]

[0044] Therefore, the present technology may include multiple channels formed in the electrostatic chuck body to increase the volume fraction of air or other fluid between the two electrodes in the puck, which may reduce the effective capacitance between the electrodes. The channels may be distributed to limit structural effects on the substrate support. For example, because the electrostatic chuck body is formed by a high-temperature, high-pressure sintering process and may subsequently operate under potentially high vacuum conditions, forming a single region in the electrostatic chuck body may cause structural collapse during formation or operation. Furthermore, heat transfer through the electrostatic chuck body may be significantly hindered by such a region, which may affect the uniformity of heating of the substrate. As a result, some embodiments of the present technology may include one or more channels in the substrate support distributed to limit mechanical and thermal effects on the operation of the substrate support while improving the electrical properties of the substrate support.

[0039]

[0045] As shown, the electrostatic chuck body may be a monolithic body of ceramic material incorporating each of the hot electrode, ground electrode, heater, and channels. As described further below, the monolith may be formed by sintering or otherwise joining multiple plates, such as a green body, which may define one or more channels, which in some embodiments may be multiple channels. Each included channel may be accessible through a stem, which may allow fluid access and, for example, prevent the channel from becoming an enclosed region within the electrostatic chuck body. A first channel 230 may be formed between the electrode 215 and the heater 225 within the electrostatic chuck body 205. A second channel 235 may be formed between the electrode 215 and the heater 225 within the electrostatic chuck body, or may be formed between the first channel 230 and the heater 225 within the chuck body. The second channel may be vertically offset from the first channel within the electrostatic chuck body, as shown.

[0040]

[0046] In some embodiments, a third channel 240 may be formed in the electrostatic chuck body between the heater 225 and the ground electrode 220. As described further below, each channel may include or consist of a set of interconnected channels, all of which may be fluidically coupled to create a single distribution channel. In embodiments, some or all of the channels may be included in the substrate support assembly, but not all of the channels may be included. For example, in some embodiments, only one of the channels may be included, or any two of the channels may be included. In one non-limiting embodiment, only the first and third channels may be included, in which case the third channel may constitute, for example, the second channel. Any number of inclusions or exclusions are similarly encompassed by embodiments of the present technology.

[0041]

[0047] Each included channel may be distributed along a respective plane through the electrostatic chuck body. For example, a first channel may extend along a first plane through the electrostatic chuck body, a second channel may extend along a second plane through the electrostatic chuck body, and a third channel may extend along a third plane through the electrostatic chuck body. The channels may be distributed along the planes to maintain structural support and sufficient heat transfer through the layer of the substrate support. For example, if both the first channel 230 and the second channel 235 are included, the channels may be offset from one another. As shown, in some embodiments, the second channel 235 may be offset from an associated portion of the first channel 230.

[0042]

[0048] While the third channel 240 is illustrated aligned with the first channel 230, in other embodiments, the third channel 240 may be aligned with the second channel 235 or may be offset from both the first channel 230 and the second channel 235. Alongside the third channel 240, there may be an additional access 245 that provides space for a thermocouple or additional sensor. Furthermore, to limit leakage from any of the channels into the chamber environment, which may be a vacuum environment, in some embodiments, the radially outermost portion of any channel may be maintained at least about 1 mm from the outer edge of the substrate support, and may be maintained about 2 mm or more, about 3 mm or more, about 4 mm or more, about 5 mm or more, about 6 mm or more, about 7 mm or more, about 8 mm or more, about 9 mm or more, about 10 mm or more, or more from the outer edge.

[0043]

[0049] As previously described, the electrostatic chuck body 205 may be formed by joining multiple plates, which may define one or more channels. The channels may be formed in a mold or green body, which may then be sintered together to form a monolithic electrostatic chuck body, which may include the channels and components described above. FIG. 3 is a schematic plan view illustrating a portion of an exemplary substrate support assembly according to some embodiments of the present technology. The figure may show a plan view of a first plate 300, which may be part of the electrostatic chuck body 205 described above. The plate may include any of the features or characteristics of the chuck body and may define a first channel 230 within its surface.

[0044]

[0050] The first channel 230 may be a set of interconnected channels formed along the surface of the plate 300. The set of interconnected channels may be fluidically connected throughout the channel, forming a single, continuous pocket within the surface. The first channel 230 may include a portion 305 extending to a central access, which may fluidly couple the first channel 230 to the stem 210 of the substrate support, thereby maintaining the first channel at atmospheric conditions or, in some embodiments, providing access for pumping or flowing fluids into or out of the channel. The interconnected channels of the first channel 230 may include multiple annular channels 310 or semi-annular channels formed within the plate. The annular channels 310 may be concentric and extend radially outward along the plate. Multiple channel interconnectors 315 may be formed between the annular channels 310, fluidly coupling the annular channels and providing fluid communication throughout the first channel 230. The first channel 230 may extend around one or more apertures 320 formed through the plate and may provide access for lift pins to extend through the substrate support. Because the lift pins may extend into the vacuum conditions of the chamber, the first channel 230, like other channels through other plates, may not extend through or intersect the apertures, limiting any access between the channel and the processing environment.

[0045]

[0051] 4 is a schematic plan view of a portion of an exemplary substrate support assembly according to some embodiments of the present technology. The figure may show a plan view of a second plate 400 that may be part of the electrostatic chuck body 205 described above. The plate may include any of the features or characteristics of the chuck body and may define a second channel 235 in its surface. The plate 400 may include any of the features of the first plate 300 described above.

[0046]

[0052] For example, the second channel 235, like the first channel 230, can be a set of interconnected channels formed along the surface of the plate 300. The set of interconnected channels can be fluidically connected throughout the channel and form a single continuous pocket within the surface. The second channel 235 can include a portion 405 extending to a central access, which can fluidly couple the second channel 235 to the stem 210 of the substrate support, thereby maintaining the second channel at atmospheric conditions or, in some embodiments, providing access for pumping or flowing fluids into or out of the channel. The interconnected channels of the second channel 235 can include multiple annular channels 410 or semi-annular channels formed within the plate. The annular channels 410 can be concentric and extend radially outward along the plate. Multiple channel interconnectors 415 can be formed between the annular channels 410, fluidly coupling the annular channels and providing fluid communication throughout the second channel 235.

[0047]

[0053] As shown, the annular channel 410 of the second plate 400 may be radially offset along the radius of the electrostatic chuck body from the annular channel 310 of the first plate 300. This may help both provide structural support for the entire substrate support when the plates are joined together and provide improved thermal coupling throughout the plates, maintaining uniform heating throughout the plates and limiting temperature effects that may otherwise be caused by the formed channels. Additionally, the plurality of second channel interconnects 415 may be azimuthally offset on the second plate from the locations on the first plate where the first channel interconnects 315 would be located. This may similarly maintain structural support for the entire thickness of the substrate support between the planes of the chuck body where the channels are formed.

[0048]

[0054] 5 is a schematic plan view of a portion of an exemplary substrate support assembly according to some embodiments of the present technology. The figure may show a plan view of a third plate 500, which may be part of the electrostatic chuck body 205 described above. The plate may include any of the features or characteristics of the chuck body and may define a third channel 240 in the surface of the plate. The plate 500 may include any of the features of the first plate 300 or second plate 400 described above.

[0049]

[0055] For example, the third channel 240, similar to the first channel 230, can be a set of interconnected channels formed along the surface of the plate 500. The set of interconnected channels can be fluidically connected throughout the channel and form a single continuous pocket within the surface. The third channel 240 can include a portion 505 extending to a central access, which can fluidly couple the third channel 240 to the stem 210 of the substrate support, thereby maintaining the third channel at atmospheric conditions or, in some embodiments, providing access for pumping or flowing fluids into or out of the channel. In some embodiments, each portion 305, 405, and 505 can be fluidly coupled to an aperture extending at least partially through the substrate support, although the aperture may not extend completely through the substrate support surface of the substrate support to limit all interaction with the processing environment, such as vacuum conditions. The interconnected channels of the third channel 240 can include multiple annular channels 510 or semi-annular channels formed within the plate. The annular channels 510 may be concentric and extend radially outward along the plate. A plurality of channel interconnects 515 may be formed between the annular channels 510, fluidly joining the annular channels and providing fluid communication across the third channel 240.

[0050]

[0056] As shown, the annular channel 510 of the third plate 500 may be radially aligned with the annular channel 310 of the first plate 300 along the radius of the electrostatic chuck body. Additionally, a plurality of second channel interconnects 515 may be azimuthally aligned in the second plate relative to the first plate at locations where the first channel interconnects 315 may be located. While some illustrated embodiments may include this interconnection arrangement, in some embodiments, the third channel 240 may be formed in various arrangements, as the third channel 240 may be further away from the first channel 230 and the second channel 235. For example, in some embodiments, the third channel 240 may be formed such that one or more of the annular channel 510 or the channel interconnects 515 are aligned with associated aspects of the second channel 235.

[0051]

[0057] Additionally, in some embodiments, the third channel 240 can be formed such that one or more of the annular channels 510 or channel interconnectors 515 are offset from associated aspects of the second channel 235 and the first channel 230, such that the interconnectors of each channel are azimuthally offset from the interconnectors of any other channel, and / or each annular channel 510 is radially offset from the annular channel of any other channel. The third plate 500 can define an additional access 245 in which a thermocouple may be seated during operation. The access 245 can be a fourth channel or recess formed in the third plate 500 and can extend radially outward along the plate from a central aperture in the third plate. As shown, the access 245, in some embodiments, may not intersect any portion of the third channel 240.

[0052]

[0058] All plates may be characterized not only by the thickness of the plate, but also by the depth of the channels formed therein. While the plate may be of any particular size, in some embodiments the channels may extend at least 25% of the thickness through the plate, and may extend about 30% or more, about 35% or more, about 40% or more, about 45% or more, about 50% or more, about 55% or more, about 60% or more, about 65% or more, about 70% or more, about 75% or more, about 80% or more, or more, into the plate, although in some embodiments the channels may not extend completely through the plate.

[0053]

[0059] 6, which is a schematic partial cross-sectional view of an exemplary substrate support 600 according to some embodiments of the present technology, which may illustrate channels. The substrate support 600 may include any feature, characteristic, or aspect of any of the components previously described, and may illustrate additional details of the substrate support 200 described above. For example, the substrate support 600 may include electrodes, heaters, and ground electrodes as described with respect to the substrate support 200, and may illustrate channels formed through the chuck body as previously described.

[0054]

[0060] As shown, the substrate support 600 may represent a portion of an electrostatic chuck body 605 having multiple channels defined therein. The substrate support may include the first channel 230, the second channel 235, and the third channel 240, as well as any of the variations described above and also encompassed by the present technology. As described above, when the plates are sintered, glued, or otherwise bonded to fabricate the chuck body 605, the channels may be aligned to maintain sufficient heat transfer through the support as well as maintain structural support for the entire chuck body. For example, each annular channel of the second channel 235 may be radially offset from the annular channel of the first channel 230. This particular cross-sectional view may extend along the channel interconnects of the first channel 230, thereby illustrating that the channel interconnects of the second channel 235 are azimuthally offset from the channel interconnects of the first channel 230. The illustrated third channel 240 is aligned with the first channel 230 radially with respect to the annular channels and azimuthally with respect to the channel interconnect that fluidly couples the annular channels.

[0055]

[0061] Once the plates are joined, which may include additional plates on one or both sides of the plate defining the channel, the complete electrostatic chuck body can be fabricated and the thickness of the chuck body can be defined. While the chuck body can be characterized by any thickness in embodiments of the present technology, in some embodiments, the electrostatic chuck body can maintain a distance between the hot electrode and the ground electrode of about 30 mm or less, and a distance between the electrodes of about 25 mm or less, about 20 mm or less, about 18 mm or less, about 16 mm or less, about 14 mm or less, about 12 mm or less, about 10 mm or less, or less. A shorter distance between the electrodes can increase the effective capacitance between the electrodes, which can result in losses within the system.

[0056]

[0062] However, by incorporating channels within the chuck body that can create fluid or air regions, the effective capacitance can be reduced. Thus, for electrode spacings within any of the described ranges, the effective capacitance through the chuck body can be about 1000 pF or less, about 980 pF or less, about 960 pF or less, about 950 pF or less, about 940 pF or less, about 930 pF or less, about 920 pF or less, about 910 pF or less, about 900 pF or less, about 890 pF or less, about 880 pF or less, about 870 pF or less, about 860 pF or less, about 850 pF or less, about 840 pF or less, about 830 pF or less, about 820 pF or less, about 810 pF or less, about 800 pF or less, about 790 pF or less, or less. This can occur by increasing the volume fraction of air within the chuck body by incorporating the aforementioned channels. For example, in some embodiments, the volume fraction of air within the electrostatic chuck body may be about 2% or greater, and may be about 4% or greater, about 6% or greater, about 8% or greater, about 10% or greater, about 12% or greater, about 14% or greater, about 16% or greater, about 18% or greater, about 20% or greater, or even greater. As previously mentioned, this volume fraction may not be the result of increased porosity, and air leakage through the chuck body may occur in these ranges. As a result, electrostatic chuck bodies according to embodiments of the present technology may be characterized by an effective capacitance similar to chuck bodies having electrode spacings that may be up to twice the distance or greater.

[0057]

[0063] FIG. 7 is a schematic plan view of a portion of an exemplary electrostatic chuck body 700 according to some embodiments of the present technique. The chuck body may be included in any system and may replace the chuck body 205 or any other component. The electrostatic chuck body 700 may include a set of channels 705 in a single layer through the chuck body to generate the air volume fraction described above. The channels 705 may be fluidly accessible through a central aperture as described above, or may be formed between the heater and hot electrode as described above. The channels 705 may be recessed from the outer edge of the substrate support to maintain fluid isolation from a processing region of a chamber in which the substrate support may be located. The top of the substrate support, including the hot electrode and substrate support surface, may be bonded, glued, or sintered to the chuck body 700, and a stem may be bonded to the backside surface to produce a substrate support assembly that may include any of the components, features, or characteristics described above. Utilizing a chuck body according to embodiments of the present technique can provide improved electrical performance while maintaining the dimensional characteristics of the substrate support.

[0058]

[0064] In the foregoing specification, for purposes of explanation, numerous 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 particular embodiments may be practiced without some of these details or with additional details.

[0059]

[0065] While several embodiments have been disclosed, 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. Moreover, in order to avoid unnecessarily obscuring the technology, many well-known processes and elements have not been described. Therefore, the above description should not be deemed to limit the scope of the technology.

[0060]

[0066] Where a range of values is provided, it is understood that each intervening value, to the smallest fraction of the unit of the lower limit, between the upper and lower limit of that range is also specifically disclosed, unless the context clearly dictates otherwise. Any narrower range between any stated value or unstated intervening value in a stated range and any other stated or intervening value in that stated range is also included. The upper and lower limits of these smaller ranges may independently be included or excluded, and each range where one or both limits are included, or neither, in the smaller ranges is also included within the technology, subject to any specifically excluded limits in the stated range. Where a stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included.

[0061]

[0067] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, a reference to "a heater" includes a plurality of such heaters, a reference to "the protrusion" includes a reference to one or more protrusions and equivalents thereof known to those skilled in the art, and so forth.

[0062]

[0068] Also, as used in this specification and the claims that follow, the terms "comprise(s)," "comprising," "contain(s)," "containing," "include(s)," and "including" specify the presence of stated features, integers, components, or steps, but do not exclude the presence or addition of one or more other features, integers, components, steps, practices, or groups.

Claims

1. 1. A substrate support assembly comprising: an electrostatic chuck body defining a substrate support surface; a support stem coupled to the electrostatic chuck body; an electrode embedded within the electrostatic chuck body adjacent the substrate support surface; a ground electrode embedded within the electrostatic chuck body; a heater embedded in the electrostatic chuck body between the electrode and the ground electrode; one or more channels formed between the electrode and the ground electrode within the electrostatic chuck body; Equipped with the one or more channels include a plurality of channels, a first channel of the plurality of channels being formed between the electrode and the heater within the electrostatic chuck body.

2. 10. The substrate support assembly of claim 1, wherein the electrostatic chuck body comprises a monolithic body of ceramic material incorporating each of the electrode, the ground electrode, and the one or more channels.

3. The substrate support assembly of claim 1 , wherein a third channel of the plurality of channels is formed within the electrostatic chuck body between the ground electrode and the heater.

4. 4. The substrate support assembly of claim 3, wherein a second channel of the plurality of channels is formed between an electrode in the electrostatic chuck body and the heater and is vertically offset from a first channel of the plurality of channels.

5. The first channel comprises a first set of interconnected channels, the first set of interconnected channels comprising: a plurality of first annular channels distributed across a first plane of the electrostatic chuck body; a plurality of first channel interconnectors radially distributed between each first annular channel of the plurality of first annular channels; The substrate support assembly of claim 4 , comprising:

6. The second channel comprises a second set of interconnected channels, the second set of interconnected channels comprising: a plurality of second annular channels distributed across a second plane of the electrostatic chuck body, the second plane of the electrostatic chuck body being vertically offset from the first plane of the electrostatic chuck body; a plurality of second channel interconnectors radially distributed between each second annular channel of the plurality of second annular channels; The substrate support assembly of claim 5 , comprising:

7. 7. The substrate support assembly of claim 6, wherein the plurality of second annular channels are radially offset from the plurality of first annular channels, and the plurality of second channel interconnects are azimuthally offset from the plurality of first channel interconnects.

8. The third channel includes a third set of interconnected channels, the third set of interconnected channels comprising: a plurality of third annular channels distributed across a third plane of the electrostatic chuck body, the third plane of the electrostatic chuck body being vertically offset from the first plane of the electrostatic chuck body and the second plane of the electrostatic chuck body; a plurality of third channel interconnectors radially distributed between each third annular channel of the plurality of third annular channels; The substrate support assembly of claim 6 , comprising:

9. 9. The substrate support assembly of claim 8, wherein each channel of the plurality of third annular channels is vertically aligned with an associated channel of the plurality of first annular channels, and the plurality of second channel interconnectors are azimuthally aligned with the plurality of first channel interconnectors.

10. a fourth channel formed in the third plane of the electrostatic chuck body and configured to seat a thermocouple extending through a support stem coupled to the electrostatic chuck body; The substrate support assembly of claim 8 , further comprising:

11. 1. A substrate support assembly comprising: an electrostatic chuck body defining a substrate support surface; a support stem coupled to the electrostatic chuck body; an electrode embedded within the electrostatic chuck body adjacent the substrate support surface; a ground electrode embedded within the electrostatic chuck body; a first set of interconnected channels formed between the electrode and the ground electrode within the electrostatic chuck body; a second set of interconnected channels formed between the electrode and the ground electrode within the electrostatic chuck body; and A substrate support assembly comprising:

12. The substrate support assembly of claim 11 , wherein the second set of interconnected channels is radially offset from the first set of interconnected channels.

13. 12. The substrate support assembly of claim 11, wherein the first set of interconnected channels is maintained at least 5 mm from a radial edge of the electrostatic chuck body.

14. The substrate support assembly of claim 11 , wherein the first set of interconnected channels and the second set of interconnected channels are maintained at atmospheric pressure.

15. A substrate support assembly as described in claim 14, wherein the effective capacitance between the electrode and the ground electrode within the electrostatic chuck body is less than or equal to approximately 1000 pF.

16. The substrate support assembly of claim 11 , wherein the electrostatic chuck body is characterized by a volume fraction of air greater than or equal to about 10%.

17. a heater positioned between the electrode and the ground electrode; a third set of interconnected channels formed between the heater and the ground electrode within the electrostatic chuck body; and The substrate support assembly of claim 11 , further comprising:

18. 1. A substrate support assembly comprising: an electrostatic chuck body defining a substrate support surface; a support stem coupled to the electrostatic chuck body; an electrode embedded within the electrostatic chuck body adjacent the substrate support surface; a ground electrode embedded within the electrostatic chuck body; a heater embedded in the electrostatic chuck body between the electrode and the ground electrode; a first set of interconnected channels formed between the electrode and the heater within the electrostatic chuck body; a second set of interconnected channels formed between the first set of interconnected channels in the electrostatic chuck body and the heater; a third set of interconnected channels formed between the heater and the ground electrode within the electrostatic chuck body; and A substrate support assembly comprising:

Images