Showerhead assembly with recursive gas channels - Patent Application 20070122997

Abstract

Showerhead embodiments are provided herein. In some embodiments, a showerhead assembly includes a chill plate including a gas plate and a cooling plate, the chill plate having an aluminum silicon foil interlayer disposed between the gas plate and the cooling plate for diffusion bonding the gas plate to the cooling plate, and a heater plate including a first plate, a second plate, and a third plate, the aluminum silicon foil interlayer disposed between the first plate and the cooling plate for diffusion bonding the first plate to the cooling plate, the aluminum silicon foil interlayer disposed between the first plate and the second plate for diffusion bonding the first plate to the second plate, and the aluminum silicon foil interlayer disposed between the second plate and the third plate for diffusion bonding the second plate to the third plate.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate generally to substrate processing apparatus, and more particularly to showerheads for use with substrate processing apparatus. [Background technology]

[0002] Conventional showerhead assemblies utilized in semiconductor process chambers (e.g., deposition chambers, etch chambers, etc.) typically include a single gas inlet that is fluidly coupled to multiple gas outlets to provide multiple gas injection points into the process volume. Multiple gas injection points provide more even flow distribution over a substrate being processed in the process chamber. The inventors have observed that using weldments to divide a single gas inlet into multiple gas outlets can result in leakage and maintainability issues. Additionally, using weldments to divide a single gas inlet into multiple gas outlets can undesirably increase the overall thickness of the showerhead assembly.

[0003] Accordingly, the present inventors provide an embodiment of an improved showerhead assembly. Summary of the Invention

[0004] Embodiments of a showerhead for use within a substrate processing chamber are provided herein. In some embodiments, a showerhead assembly for use within a substrate processing chamber is a chill plate comprising a gas plate and a cooling plate, the chill plate having an aluminum silicon foil intermediate layer disposed between the gas plate and the cooling plate for diffusion bonding the gas plate to the cooling plate, and a heater plate comprising a first plate, a second plate, and a third plate, wherein an aluminum silicon foil intermediate layer is disposed between the first plate and the cooling plate for diffusion bonding the first plate to the cooling plate, an aluminum silicon foil intermediate layer is disposed between the first plate and the second plate for diffusion bonding the first plate to the second plate, and an aluminum silicon foil intermediate layer is disposed between the second plate and the third plate for diffusion bonding the second plate to the third plate.

[0005] In some embodiments, a process chamber comprises a chamber body defining an internal space therein, a substrate support disposed within the internal space for supporting a substrate, and a showerhead assembly disposed within the internal space on a side opposite the substrate support, the showerhead assembly being a chill plate comprising a gas plate and a cooling plate, the chill plate having an aluminum silicon foil intermediate layer disposed between the gas plate and the cooling plate for diffusion bonding the gas plate to the cooling plate, and a heater plate comprising a first plate, a second plate, and a third plate, wherein an aluminum silicon foil intermediate layer is disposed between the first plate and the cooling plate for diffusion bonding the first plate to the cooling plate, an aluminum silicon foil intermediate layer is disposed between the first plate and the second plate for diffusion bonding the first plate to the second plate, and an aluminum silicon foil intermediate layer is disposed between the second plate and the third plate for diffusion bonding the second plate to the third plate.

[0006] In some embodiments, a method of manufacturing a showerhead assembly for use within a substrate processing chamber includes providing an aluminum-silicon foil intermediate layer between a gas plate of a chill plate and a cooling plate of the chill plate and diffusion bonding the gas plate to the cooling plate; providing an aluminum-silicon foil intermediate layer between a first plate of a heater plate and the cooling plate and diffusion bonding the first plate to the cooling plate; providing an aluminum-silicon foil intermediate layer between the first plate and a second plate of the heater plate and diffusion bonding the first plate to the second plate; and providing an aluminum-silicon foil intermediate layer between the second plate and a third plate of the heater plate and diffusion bonding the second plate to the third plate.

[0007] Other and further embodiments of the present disclosure are described below.

[0008] Embodiments of the present disclosure, briefly summarized above and discussed in more detail below, may be understood by reference to the exemplary embodiments of the present disclosure depicted in the accompanying drawings. However, the accompanying drawings merely illustrate typical embodiments of the present disclosure and should not be considered limiting with respect to the scope since the present disclosure may admit to other equally effective embodiments.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

DETAILED DESCRIPTION OF THE INVENTION

[0010] For the sake of understanding, the same reference numbers are used whenever possible to identify the same elements common to the figures. The figures are not drawn to scale and may be simplified for clarity. Elements and features of one embodiment may be beneficially incorporated into other embodiments without further elaboration.

[0011] Embodiments of a shower head assembly for use within a process chamber are provided herein. The shower head assembly is configured to facilitate the flow of process gas to a substrate being processed within the processing chamber. In some embodiments, the shower head assembly is configured to operate for high power supply. The shower head assembly includes a heater plate configured to heat the shower head assembly. The shower head assembly includes a chill plate through which cooling channels pass to cool the shower head assembly. The shower head assembly includes one or more recursive gas paths extending from a single gas inlet to a plurality of gas outlets. In some embodiments, the one or more recursive gas paths are advantageously disposed within the chill plate to minimize the thickness of the shower head assembly.

[0012] In at least some embodiments, the chill plate comprises a gas plate and a chill plate having a eutectic or near-eutectic aluminum silicon foil interlayer disposed between the gas plate and the chill plate to assist in diffusion bonding the gas plate to the chill plate. Further, the heater plate comprises a first plate, a second plate, and a third plate, with a eutectic or near-eutectic aluminum silicon foil interlayer disposed between the first plate and the chill plate to assist in diffusion bonding the first plate to the chill plate, and a eutectic or near-eutectic aluminum silicon foil interlayer disposed between one or more of the first plate, the second plate, and the third plate to assist in diffusion bonding one or more of the first plate, the second plate, and the third plate to each other.

[0013] FIG. 1 shows a schematic side view of a portion of a process chamber according to some embodiments of the present disclosure. In some embodiments, the process chamber is an etch chamber. However, other types of processing chambers configured for different processes may further use, or be modified for use with, the embodiments of the showerhead assembly described herein.

[0014] The process chamber 100 is a vacuum chamber suitably adapted to maintain a near-atmospheric pressure within the internal space 120 during substrate processing. The process chamber 100 includes a chamber body 106 having side walls and a bottom wall. The chamber body 106 is covered by a lid 104, and the chamber body 106 and the lid 104 together define the internal space 120. The chamber body 106 and the lid 104 may be made of a metal such as aluminum. The chamber body 106 may be grounded by connection to ground 115.

[0015] The substrate support 124 is disposed within the internal space 120 to support and hold a substrate 122, such as a semiconductor wafer, or other substrates that can be electrostatically held. The substrate support 124 generally may include a pedestal 128 and a hollow support shaft 112 for supporting the pedestal 128. The pedestal 128 may include an electrostatic chuck 150. The electrostatic chuck 150 includes a dielectric plate having one or more electrodes 154 disposed therein. The hollow support shaft 112 provides conduits, for example, to the pedestal 128 for providing backside gas, process gas, fluid, coolant, power, or the like.

[0016] The substrate support 124 is coupled to the electrostatic chuck 150 and to a chuck power supply 140 and an RF source (e.g., an RF bias power supply 117 or an RF plasma power supply 170). In some embodiments, a backside gas supply 142 is disposed outside the chamber body 106 and supplies a heat transfer gas to the electrostatic chuck 150. In some embodiments, the RF bias power supply 117 is coupled to the electrostatic chuck 150 via one or more RF match networks 116. In some embodiments, the substrate support 124 may alternatively include AC or DC bias power.

[0017] The process chamber 100 is also coupled to a gas supply 118 and in fluid communication with the gas supply 118, which can supply one or more process gases to the process chamber 100 for processing a substrate 122 disposed within the process chamber 100. A showerhead assembly 132 is disposed on the side of the substrate support 124 within the internal space 120 that is opposite. In some embodiments, the showerhead assembly 132 is coupled to the lid 104. The showerhead assembly 132 and the substrate support 124 partially define a throughput 144 therebetween. The showerhead assembly 132 includes a plurality of apertures for distributing one or more process gases from the gas supply 118 into the throughput 144. The showerhead assembly 132 includes a chill plate 138, which is for controlling the temperature of the showerhead assembly 132 and the holes / channels (described in more detail below) to provide a gas flow path through the chill plate 138. The showerhead assembly 132 includes a heater plate 141 coupled to the chill plate 138. The heater plate 141 includes one or more heating elements disposed or embedded within the heater plate 141 for controlling the temperature of the showerhead assembly 132 and for including holes / channels (described in more detail below) to provide a gas flow path through the heater plate 141. In some embodiments, the showerhead assembly 132 includes an upper electrode 136 coupled to the heater plate 141. The upper electrode 136 is disposed on the side of the substrate support 124 within the internal space 120 that is opposite. The upper electrode 136 is coupled to one or more power supplies (e.g., an RF plasma power supply 170) for igniting one or more process gases. In some embodiments, the upper electrode 136 comprises single crystal silicon or other silicon-containing material.

[0018] The liner 102 is disposed around at least one of the substrate support 124 and the showerhead assembly 132 within the internal space 120 to confine the plasma within the internal space 120. In some embodiments, the liner 102 is made of a suitable process material such as an aluminum or silicon-containing material. The liner 102 includes an upper liner 160 and a lower liner 162. The upper liner 160 may be made of any of the materials described above. In some embodiments, the lower liner 162 is made of the same material as the upper liner 160. In some embodiments, the upper liner 160 includes a stepped inner surface that matches the stepped outer surface 188 of the upper electrode 136.

[0019] The lower liner 162 includes a plurality of radial slots 164 disposed around the lower liner 162 to provide a flow path for process gas to the pump port 148 (discussed below). In some embodiments, the liner 102, together with the showerhead assembly 132 and the pedestal 128, at least partially defines the throughput 144. In some embodiments, the outer diameter of the showerhead assembly 132 is smaller than the outer diameter of the liner 102 and larger than the inner diameter of the liner 102. The liner 102 includes an opening 105 that aligns with a slit 103 in the chamber body 106 for moving the substrate 122 in and out of the process chamber 100.

[0020] In some embodiments, the liner 102 is coupled to a heater ring 180 to heat the liner 102 to a predetermined temperature. In some embodiments, the liner 102 is coupled to the heater ring 180 via one or more fasteners 158. A heater power supply 156 is coupled to one or more heating elements within the heater ring 180 to heat the heater ring 180 and the liner 102.

[0021] The process chamber 100 is coupled to and in fluid communication with a vacuum system 114 that includes a throttle valve and a vacuum pump used to evacuate the process chamber 100. The pressure inside the process chamber 100 may be adjusted by adjusting the throttle valve and / or the vacuum pump. The vacuum system 114 may be coupled to a pump port 148.

[0022] In some embodiments, the liner 102 is supported by a lower tray 110. The lower tray 110 is configured to direct the flow of one or more process gases and process by-products from a plurality of radial slots 164 to the pump port 148. In some embodiments, the lower tray 110 includes an outer sidewall 126, an inner sidewall 130, and a lower wall 134 extending from the outer sidewall 126 to the inner sidewall 130. The outer sidewall 126, the inner sidewall 130, and the lower wall 134 define an evacuation volume 184 therebetween. In some embodiments, the outer sidewall 126 and the inner sidewall 130 are annular. The lower wall 134 includes one or more openings 182 (one is shown in FIG. 1) to fluidly couple the evacuation volume 184 to the vacuum system 114. The lower tray 110 is supported by the pump port 148 or may alternatively be coupled to the pump port 148. In some embodiments, the lower tray 110 includes a ledge 152 extending radially inwardly from the inner sidewall 130 to accommodate a chamber component, such as a pedestal 128 of the substrate support 124. In some embodiments, the lower tray 110 is made of a conductive material, such as aluminum, to provide a ground path.

[0023] In operation, for example, plasma may be created within throughput 144 to perform one or more processes. The plasma may be created by igniting a process gas and coupling power from a plasma power supply (e.g., RF plasma power supply 170) to the process gas via one or more electrodes (e.g., upper electrode 136) near or within the internal space 120. Bias power may further be provided from a bias power supply (e.g., RF bias power supply 117) to one or more electrodes 154 within the electrostatic chuck 150 to attract ions from the plasma towards the substrate 122.

[0024] The plasma sheath may bend at the edge of the substrate 122, causing ions to accelerate at right angles to the plasma sheath. The ions may be focused or deflected at the substrate edge due to the bend in the plasma sheath. In some embodiments, the substrate support 124 includes an edge ring 146 disposed around the electrostatic chuck 150. In some embodiments, the edge ring 146 and the electrostatic chuck 150 define a substrate receiving surface. The edge ring 146 may be coupled to a power source such as the RF bias power supply 117, or a second RF bias power supply (not shown), to control and / or reduce the bend of the plasma sheath.

[0025] FIG. 2 shows a cross-sectional view of a showerhead assembly 132 according to some embodiments of the present disclosure. The showerhead assembly 132 includes a chill plate 138 having one or more cooling channels 204 disposed within or embedded in the chill plate 138. The showerhead assembly 132 includes a heater plate 141 coupled to the chill plate 138. The heater plate 141 includes one or more heating elements 208 disposed within or embedded in the heater plate 141. The one or more heating elements 208 may be disposed within one or more heating zones to provide independent temperature control for two or more gas zones of the showerhead assembly 132. The one or more heating elements 208 are coupled to one or more power supplies 290. The showerhead assembly 132 includes a plurality of gas flow paths that are fluidly independent of each other and extend through the showerhead assembly 132. In some embodiments, the chill plate 138 is made of aluminum. In some embodiments, the heater plate 141 is made of aluminum.

[0026] The chill plate 138 includes a plurality of recursive gas paths 206 disposed within the chill plate 138 that are fluidly independent of each other and correspond to two or more gas zones of the showerhead assembly 132. For example, the plurality of recursive gas paths 206 can include two, three, or four recursive gas paths (two recursive gas paths are shown in FIGS. 3 and 4). Each of the plurality of recursive gas paths 206 is fluidly coupled to a single gas inlet extending to a first side 218 of the chill plate 138 and a plurality of gas outlets 248 extending to a second side 224 of the chill plate 138. Each of the recursive gas paths 206 can have a substantially equivalent flow path (i.e., substantially equivalent axial length and cross-sectional area) from the single gas inlet to each of the plurality of gas outlets 248. In some embodiments, the substantially equivalent flow paths can have lengths within 10% of each other. The substantially equivalent flow paths advantageously result in a more uniform gas distribution into the throughput 144 through the showerhead assembly 132.

[0027] In some embodiments, the plurality of recursive gas paths 206 are arranged along a common plane (i.e., a single layer) around the chill plate 138. In some embodiments, at least one of the plurality of recursive gas paths 2 is arranged along two or more planes (i.e., two or more layers) around the chill plate 138, where connection channels (such as connection channel 220) couple the multiple layers of the plurality of recursive gas paths 206. The two or more layers advantageously enable an increase in the volume for the plurality of recursive gas paths 206 to extend into the chill plate 138 compared to a single layer. FIG. 2 shows at least one of the plurality of recursive gas paths 206 arranged along two planes.

[0028] In some embodiments, the chill plate 138 comprises one or more plates coupled to each other. As shown in FIG. 2, in some embodiments, the chill plate 138 includes a gas plate 230 having a first side 238 coupled to an upper plate 228 and a second side 240 coupled to a cooling plate 232. The bottom surface of the upper plate 228 is coupled to the upper surface of the gas plate 230 by one or more joining processes, such as brazing, diffusion bonding, etc. For example, in at least some embodiments, the bottom surface of the upper plate 228 is coupled to the upper surface of the gas plate 230 using a eutectic or near-eutectic (e.g., 577 °C) aluminum silicon foil interlayer 229 (interlayer 229) to assist with diffusion bonding. In at least some embodiments, the interlayer 229 can have a thickness of from about 1 mil to about 10 mils. Further, the bottom surface of the gas plate 230 is also coupled to the upper surface of the cooling plate 232 using the interlayer 229 to assist with diffusion bonding. The cooling plate 232 is coupled to a bottom plate 234 on the side of the cooling plate 232 opposite the gas plate 230. The bottom surface of the cooling plate 232 can be coupled to the upper surface of the bottom plate 234 using the interlayer 229 to assist with diffusion bonding. Similarly, the bottom surface of the bottom plate 234 can be coupled to one or more of the plates of the heater plate 141, as described in more detail below.

[0029] In at least some embodiments, the intermediate layer 229 used to diffusion bond the above-described plates to each other may be the same or different. For example, the weight percentage of aluminum relative to silicon used in the intermediate layer 229 can vary between different plates. For example, in at least some embodiments, the intermediate layer 229 used to diffusion bond the bottom surface of the upper plate 228 to the upper surface of the gas plate 230 can have about 88 weight percent aluminum and about 12 weight percent silicon. Similarly, the intermediate layer 229 used to diffusion bond the bottom surface of the gas plate 230 to the upper surface of the cooling plate 232 can have about 80 weight percent aluminum and about 20 weight percent silicon, and the intermediate layer 229 used to diffusion bond the bottom surface of the cooling plate 232 to the upper surface of the bottom plate 234 can have about 88 weight percent aluminum and about 12 weight percent silicon.

[0030] One or more cooling channels 204 are arranged along the bottom surface 242 of the cooling plate 232. In some embodiments, a plurality of recirculating gas paths 206 are arranged on at least one of the first side surface 238 and the second side surface 240 of the gas plate 230. In some embodiments, one or more of the plurality of recirculating gas paths 206 are arranged on both the first side surface 238 and the second side surface 240 in embodiments where the plurality of recirculating gas paths 206 are arranged in two layers within the chiller plate 138. In such embodiments, the recirculating gas paths located along the two layers include connection channels 220 that fluidly couple the two layers. In embodiments where the recirculating gas paths 206 are arranged along three or more layers, the gas plate 230 can comprise two or more plates coupled to each other. The bottom plate 234 includes an opening that at least partially defines a plurality of gas outlets 248.

[0031] In some embodiments, the first gas inlet 212 extends from the first side surface 218 of the chill plate 138 (i.e., the upper surface of the plate 228) to the first recursive gas path 310 (see FIG. 3) among the plurality of recursive gas paths 206. In some embodiments, the second gas inlet 216 extends from the first side surface 218 of the chill plate 138 to the second recursive gas path 330 (see FIG. 3) among the plurality of recursive gas paths 206.

[0032] In some embodiments, each of the plurality of recursive gas paths 206 is coupled to a gas supply 118. The gas supply can be configured to supply one or more process gases to any one or more of the recursive gas paths. For example, in some embodiments, the gas supply 118 is configured to supply a single process gas to each of the first recursive gas path 310 and the second recursive gas path 330. In some embodiments, the gas supply 118 is configured to supply a first process gas or gaseous mixture to one or more of the first recursive gas path 310 and the second recursive gas path 330, and a second process gas or gaseous mixture to the remaining portions of the first recursive gas path 310 and the second recursive gas path 330. In some embodiments, the gas supply 118 is configured to supply different process gases or gaseous mixtures to each of the recursive gas paths.

[0033] The heater plate 141 includes one or more heating elements 208. In some embodiments, the heater plate 141 includes a plurality of first gas distribution holes 252 that extend from the upper surface 250 of the heater plate 141 to a plurality of plenums 256 that are fluidly independent and disposed within the heater plate 141. A plurality of second gas distribution holes 254 extend from the plurality of plenums 256 to the lower surface 258 of the heater plate to provide a gas flow path through the heater plate 141. In some embodiments, the plurality of second gas distribution holes 254 have more holes than the plurality of first gas distribution holes 252 to more uniformly disperse one or more process gases into the throughput 144.

[0034] The plurality of first gas distribution holes 252 are aligned with the plurality of gas outlets 248 of the chill plate 138. In some embodiments, the plurality of plenums 256 coincide with the plurality of recirculating gas paths 206. In some embodiments, the showerhead assembly 132 includes an upper electrode 136 coupled to the heater plate 141. The upper electrode 136 includes a plurality of third gas distribution holes 274 that extend from a position corresponding to the position of the plurality of second gas distribution holes 254 of the heater plate 141 at the upper surface 276 of the upper electrode to the lower surface 278 of the upper electrode 136. In some embodiments, the plurality of third gas distribution holes 274 have a diameter from about 10 mils to about 50 mils. The upper electrode 136, the heater plate 141, and the chill plate 138 can be coupled to each other via fasteners, spring tensioners, or the like.

[0035] In some embodiments, each of the plurality of gas flow paths through the showerhead assembly 132 that are fluid independent of each other passes through the chill plate 138, from the respective gas inlet on the first side surface 218 of the chill plate 138, through the recirculating flow path within the chill plate 138, to the respective plurality of gas outlets (e.g., gas outlets 248) on the second side surface 224 of the chill plate 138, passes through the heater plate 141, through the respective hole of the plurality of first gas distribution holes 254, through the respective plenum of the plurality of plenums 256, and through the respective hole of the plurality of second gas distribution holes 254, passes through the upper electrode 136, and extends through the plurality of third gas distribution holes 274. For example, a first gas flow path passes through a corresponding gas distribution hole of the plurality of first gas distribution holes 252 from a plurality of gas outlets 248 associated with a first recirculating gas path 410 and extends into a first plenum of the plurality of plenums 256. Similarly, a second gas flow path passes through a corresponding gas distribution hole of the plurality of first gas distribution holes 252 from a plurality of gas outlets 248 associated with a second recirculating gas path 330 and extends into a second plenum of the plurality of plenums 256.

[0036] In some embodiments, the heater plate 141 comprises one or more plates coupled to each other. In some embodiments, the heater plate 141 includes a first plate 262 coupled to a second plate 264. As described above, the bottom surface of the bottom plate 234 can be coupled to one or more plates of the heater plate 141. For example, in at least some embodiments, the bottom surface of the bottom plate 234 can be coupled to the top surface of the first plate 262 using an intermediate layer 229 to assist with diffusion bonding. Alternatively, if the bottom plate 234 is not used, the bottom surface of the cooling plate 232 can be coupled to the top surface of the first plate 262 using an intermediate layer 229 to assist with diffusion bonding. Further, in at least some embodiments, the bottom surface of the first plate 262 can be coupled to the top surface of the second plate 264 using an intermediate layer 229 to assist with diffusion bonding. One or more heating elements 208 are disposed within a plurality of channels 268. In some embodiments, the plurality of channels 268 are disposed within the first plate 262. In some embodiments, the plurality of channels 268 are disposed within the second plate 264. In some embodiments, the plurality of channels 268 are defined by both the first plate 262 and the second plate 264. In some embodiments, both the first plate 262 and the second plate 264 include a plurality of channels 268. In some embodiments, a third plate 266 is coupled to the second plate 264 on a side surface of the second plate 264 opposite the first plate 262. In at least some embodiments, the bottom surface of the second plate 264 can be coupled to the top surface of the third plate 266 using an intermediate layer 229 to assist with diffusion bonding. In some embodiments, the third plate 266 includes a second plurality of channels 272 that define a plurality of plenums 256. As described above, the intermediate layer 229 used to diffusion bond the first plate to the third plate relative to each other can be the same or different, for example, using the weight percentage of aluminum relative to silicon described above.

[0037] One or more optional thermal gaskets may be disposed between the chill plate 138 and the heater plate 141 to provide an enhanced thermal bond and a compression interface therebetween. For example, in some embodiments, a first thermal gasket sheet 280 may be disposed between the chill plate 138 and the heater plate 141 to provide an enhanced thermal bond and a compression interface therebetween. In some embodiments, a second thermal gasket sheet 282 may be disposed between the heater plate 141 and the upper electrode 136 to provide an enhanced thermal bond and a compression interface therebetween. The first thermal gasket sheet 280 includes a plurality of openings that coincide with the positions of the plurality of first gas distribution holes 252 of the heater plate 141. The second thermal gasket sheet 282 includes a plurality of openings that coincide with the positions of the plurality of second gas distribution holes 254 of the heater plate 141. The first thermal gasket sheet 280 and the second gasket sheet 281 are made from a thermally and electrically conductive material sheet. In some embodiments, the first thermal gasket sheet 280 and the second gasket sheet 281 comprise a polymeric material. In some embodiments, the first thermal gasket sheet 280 and the second gasket sheet 281 comprise an elastomer-metal sandwich structure.

[0038] FIG. 3 shows a top view of the gas plate 230 of the chill plate 138 according to some embodiments of the present disclosure. FIG. 4 shows a bottom view of the gas plate 230 according to some embodiments of the present disclosure. The gas plate 230 shown in FIGS. 3 and 4 has a plurality of recursive gas paths 206 arranged along two layers of the gas plate 230. FIG. 3 shows an embodiment of a first layer 300 of the plurality of recursive gas paths 206. FIG. 4 shows an embodiment of a second layer 400 of the plurality of recursive gas paths 206.

[0039] The plurality of recursive gas paths 206 can each be disposed in at least one of the first layer 300 and the second layer 400. In some embodiments, one or more of the plurality of recursive gas paths 206 extend from the second layer 400 to the first layer 300 and back to the second layer 400. In some embodiments, the first gas inlet 212 extends to the first layer 300 and is fluidly coupled to a first recursive gas path 310 disposed in both the first layer 300 and the second layer 400. In some embodiments, the first recursive gas path 310 branches one or more times from the first gas inlet 212 within the first layer 300 to a plurality of ends that coincide with connection channels 220A that fluidly couple the plurality of layers of the first recursive gas path 310. In some embodiments, the first recursive gas path 310 branches once to two ends that coincide with two connection channels 220A.

[0040] In some embodiments, within the second layer 400, the first recursive gas path 310 branches one or more times from each of the connection channels 220A to a plurality of first ends 415. In some embodiments, the first recursive gas path 310 branches once from each connection channel 220A within the second layer 400 to form four first ends 415. In some embodiments, the plurality of first ends 415 are symmetrically disposed around the gas plate 230. In some embodiments, the plurality of first ends 415 are positioned at regular intervals along a virtual circle. In some embodiments, the first recursive gas path 310 includes an annular extension and a radial extension within the second layer 400. The plurality of second ends 435 are aligned with a first subset 248A of the plurality of gas outlets 248 of the chill plate 138. In some embodiments, the first recursive gas path 310 branches twice from each connection channel 220A within the second layer 400 to form eight first ends 415.

[0041] In some embodiments, a second recirculation gas path 330 extends from a second gas inlet 216 to a second layer 400, extends to a first layer 300, and then returns to the second layer 400. In this way, the second recirculation gas path 330 can be disposed within both the first layer 300 and the second layer 400. In some embodiments, the second recirculation gas path 330 branches one or more times within the second layer 400 from a second gas inlet 216 to a plurality of ends that coincide with connection channels 220C that fluidly couple the plurality of layers of the second recirculation gas path 330. In some embodiments, the second recirculation gas path 330 branches once to form two ends that coincide with two connection channels 220C.

[0042] In some embodiments, within the first layer 300, the second recirculation gas path 330 branches one or more times from each of the connection channels 220C to an end that coincides with a connection channel 220D. In some embodiments, the second recirculation gas path 330 branches once from each of the connection channels 220C to form four ends that coincide with four connection channels 220D.

[0043] In some embodiments, within the second layer 400, the second recirculating gas path 330 branches one or more times from each of the connection channels 220D to a plurality of second ends 435. In some embodiments, the second recirculating gas path 330 branches once within the second layer 400 from each connection channel 220D to form a total of eight second ends 435. In some embodiments, the plurality of second ends 435 are symmetrically arranged around the gas plate 230. In some embodiments, the plurality of second ends 435 are arranged at regular intervals along a virtual circle. In some embodiments, the second recirculating gas path 330 includes an annular extension and a radial extension within the second layer 400. The plurality of second ends 435 are aligned with a second subset 248B of the plurality of gas outlets 248 of the chill plate 138. In some embodiments, the second recirculating gas path 330 is arranged radially outward from the first recirculating gas path 310. In some embodiments, the second recirculating gas path 330 branches twice within the second layer 400 from each connection channel 220D to form 16 second ends 435.

[0044] FIG. 5 shows a bottom cross-sectional view of the chill plate 138 of the showerhead assembly 132 according to some embodiments of the present disclosure. In some embodiments, the plurality of gas outlets 248 are arranged along concentric circles of the chill plate 138. In some embodiments, the plurality of gas outlets 248 are arranged at regular intervals along concentric circles of the chill plate 138. In some embodiments, the gas outlets among the plurality of gas outlets 248 in each concentric circle coincide with different gas distribution zones of the showerhead assembly 132. In some embodiments, the showerhead assembly 132 includes two gas distribution zones, a first zone being the innermost zone in the radial direction and a second zone being the outermost zone in the radial direction. In some embodiments, the showerhead assembly 132 includes four zones, a first zone being the innermost zone in the radial direction, a second zone being radially outside the first zone, a third zone being radially outside the second zone, and a fourth zone being the outermost zone in the radial direction and being radially outside the third zone.

[0045] In some embodiments, one or more cooling channels 204 include one cooling channel having an inlet 510 for supplying coolant through the cooling channel and an outlet 520 for providing a return path for the coolant. In some embodiments, one or more cooling channels 204 extend proximate each zone. In some embodiments, one or more cooling channels 204 are arranged in a spiral pattern.

[0046] FIG. 6 shows a cross-sectional top view of a heater plate 141 of a showerhead assembly 132 according to some embodiments of the present disclosure. One or more heating elements 208 can extend around the heater plate 141 in any suitable pattern for heating the heater plate 141. In some embodiments, one or more heating elements 208 are two or more heating elements that define two or more such heating zones of the showerhead assembly 132. In some embodiments, one or more heating elements 208 include a first heating element 610 proximate the center of the heater plate 141. In some embodiments, one or more heating elements 208 include a second heating element 620 disposed radially outward of the first heating element 610. In some embodiments, the second heating element 620 extends radially outward beyond the outermost set 612 of the plurality of first gas distribution holes 252 in the radial direction.

[0047] FIG. 7 shows a cross-sectional top view of the heater plate 141 along the plane of a plurality of plenums 256 according to some embodiments of the present disclosure. In some embodiments, the plurality of plenums 256 coincide with a plurality of gas distribution zones. In some embodiments, the plurality of plenums 256 comprises two plenums that coincide with two gas distribution zones. In some embodiments, the plurality of plenums 256 comprises four plenums that coincide with four gas distribution zones. In some embodiments, a first plenum 720 is fluidly coupled to a first subset 252A of the first gas distribution holes 252 associated with the first recirculating gas path 310. In some embodiments, a second plenum 740 is fluidly coupled to a second subset 252B of the plurality of first gas distribution holes 252 associated with the second recirculating gas path 330. The first plenum 720 is fluidly coupled to a first subset 254A of the plurality of second gas distribution holes 254. The second plenum 740 is fluidly coupled to a second subset 254B of the plurality of second gas distribution holes 254. The plurality of second gas distribution holes 254 are evenly distributed within each plenum. The first plenum 720 and the second plenum 740 can include a plurality of walls 702 to direct the gas flow from the plurality of first gas distribution holes 252 to the plurality of second gas distribution holes 254 within each plenum. In some embodiments, the plurality of walls 702 have a polygonal cross-sectional shape. In some embodiments, the plurality of walls 702 are curved. In some embodiments, the plurality of second gas distribution holes 254 comprises more than 100 holes within the plurality of plenums 256. In some embodiments, the plurality of second gas distribution holes 254 are arranged within concentric circles. In some embodiments, the second gas distribution holes 254 within each concentric circle are spaced at regular intervals along the concentric circle. Each plenum of the plurality of plenums 256 can include one or more concentric circles of the second gas distribution holes 254. In some embodiments, the plurality of second gas distribution holes 254 have a diameter from about 10 mils to about 50 mils.

[0048] The foregoing is directed to embodiments of the present disclosure, but other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof.

Claims

1. 1. A showerhead assembly for use in a substrate processing chamber, comprising: a chill plate comprising a gas plate and a cooling plate, the chill plate having an aluminum silicon foil interlayer disposed between the gas plate and the cooling plate for diffusion bonding the gas plate to the cooling plate; a heater plate comprising a first plate, a second plate, and a third plate; an aluminum silicon foil interlayer disposed between the first plate and the cooling plate to diffusion bond the first plate to the cooling plate, an aluminum silicon foil interlayer disposed between the first plate and the second plate to diffusion bond the first plate to the second plate, and an aluminum silicon foil interlayer disposed between the second plate and the third plate to diffusion bond the second plate to the third plate.

2. 10. The showerhead assembly of claim 1, further comprising a top plate, an aluminum silicon foil interlayer disposed between the top plate and the gas plate for diffusion bonding the top plate to the gas plate.

3. 10. The showerhead assembly of claim 1, further comprising a bottom plate, an aluminum silicon foil interlayer disposed between the cooling plate and the bottom plate for diffusion bonding the cooling plate to the bottom plate.

4. 4. The showerhead assembly of claim 3, wherein an aluminum silicon foil interlayer is disposed between the bottom plate and the first plate for diffusion bonding the bottom plate to the first plate.

5. 10. The showerhead assembly of claim 1, wherein the aluminum silicon foil interlayer used to diffusion bond the gas plate to the cooling plate, the first plate to the cooling plate, the first plate to the second plate, and the second plate to the third plate has about 80 weight percent aluminum and about 20 weight percent silicon.

6. 6. The showerhead assembly of claim 5, wherein the aluminum silicon foil interlayer used to diffusion bond the gas plate to the cooling plate, the first plate to the cooling plate, the first plate to the second plate, and the second plate to the third plate is a eutectic or near-eutectic compound.

7. The chill plate is a plurality of recursive gas paths disposed within the chill plate that are fluidly independent of one another; and one or more cooling channels disposed within the chill plate. each of the plurality of recursive gas paths is fluidly coupled to a single gas inlet extending to a first side of the chill plate and a plurality of gas outlets extending to a second side of the chill plate; 7. The showerhead assembly of claim 1, wherein the heater plate includes: one or more heating elements disposed within the heater plate; a plurality of first gas distribution holes extending from an upper surface of the heater plate to a plurality of plenums disposed fluidly independently within the heater plate, the plurality of first gas distribution holes coinciding with the plurality of gas outlets of the chill plate; and a plurality of second gas distribution holes extending from the plurality of plenums to a lower surface of the heater plate.

8. 10. The showerhead assembly of claim 7, further comprising an upper electrode coupled to the heater plate and having a plurality of third gas distribution holes extending from an upper surface of the upper electrode to a lower surface of the upper electrode at locations corresponding to locations of the plurality of second gas distribution holes in the heater plate.

9. 10. The showerhead assembly of claim 8, further comprising: a first thermal gasket sheet disposed between the chill plate and the heater plate; and a second thermal gasket sheet disposed between the heater plate and the upper electrode.

10. 8. The showerhead assembly of claim 7, wherein the plurality of recursive gas paths are disposed along two layers of the chill plate.

11. 8. The showerhead assembly of claim 7, wherein the gas plate has a first side coupled to a top plate and a second side coupled to the cooling plate, and a bottom plate coupled to the cooling plate opposite the gas plate, wherein at least one of the plurality of recursive gas paths is disposed on the first side and the second side of the gas plate, and wherein the one or more cooling channels are disposed in the cooling plate.

12. 8. The showerhead assembly of claim 7, wherein each of the plurality of recursive gas paths has a substantially equal flow path from the single gas inlet to each of the plurality of gas outlets.

13. 8. The showerhead assembly of claim 7, wherein the one or more heating elements of the heater plate define two or more heating zones of the showerhead assembly.

14. 8. The showerhead assembly of claim 7, wherein the first plate has a plurality of channels to accommodate the one or more heating elements, the second plate is coupled to the first plate to cover the plurality of channels, and the third plate is coupled to the second plate on an opposite side of the first plate, the third plate having a second plurality of channels that define the plurality of plenums.

15. 8. The showerhead assembly of claim 7, wherein the plurality of recursive gas paths comprises four recursive gas paths, and the plurality of plenums comprises four plenums to define four gas distribution zones in a lower surface of the showerhead assembly.

16. 1. A process chamber comprising: a chamber body defining an interior space therein; a substrate support disposed within the interior space for supporting a substrate; the showerhead assembly of claim 1 , disposed in the interior space on an opposite side to the substrate support; A process chamber comprising:

17. The chill plate is a plurality of recursive gas paths disposed within the chill plate that are fluidly independent of one another; and one or more cooling channels disposed within the chill plate. each of the plurality of recursive gas paths is fluidly coupled to a single gas inlet extending to a first side of the chill plate and a plurality of gas outlets extending to a second side of the chill plate; 17. The process chamber of claim 16, wherein the heater plate includes: one or more heating elements disposed within the heater plate; a plurality of first gas distribution holes extending from an upper surface of the heater plate to a plurality of plenums disposed fluidly independently within the heater plate, the plurality of first gas distribution holes coinciding with the plurality of gas outlets of the chill plate; and a plurality of second gas distribution holes extending from the plurality of plenums to a lower surface of the heater plate.

18. The showerhead assembly further comprising a bottom plate coupled to the cooling plate opposite the gas plate; 20. The process chamber of claim 17, wherein an aluminum silicon foil interlayer is disposed between the bottom plate and the first plate for diffusion bonding the bottom plate to the first plate.

19. 17. The process chamber of claim 16, wherein a plurality of recursive gas paths are disposed along two layers of the chill plate.

20. 1. A method of manufacturing a showerhead assembly for use in a substrate processing chamber, comprising: providing an aluminum silicon foil interlayer between a gas plate of a chill plate and a cooling plate of the chill plate, and diffusion bonding the gas plate to the cooling plate; providing an aluminum silicon foil interlayer between a first plate of a heater plate and the cooling plate, and diffusion bonding the first plate to the cooling plate; providing an aluminum silicon foil interlayer between the first and second plates of the heater plate and diffusion bonding the first plate to the second plate; providing an aluminum silicon foil interlayer between the second plate and a third plate of the heater plate, and diffusion bonding the second plate to the third plate; A method for manufacturing a showerhead assembly, comprising:

Images