JP2021525963A - Temperature controlled gas diffuser for flat panel process equipment - Google Patents

Abstract

The embodiments described herein provide a gas distribution assembly that improves the uniformity of deposited or etched membranes. One embodiment of the gas distribution assembly includes a diffuser having an upper diffuser plate and a plurality of first gas passage sections disposed within the upper diffuser plate. Each first gas passage is adjacent to at least one fluid channel located in the upper diffuser plate. Each fluid channel is coupled to a supply channel located in the upper diffuser plate, which has a supply inlet configured to be coupled to the fluid supply conduit of the heat exchanger. Each fluid channel is connected to a return channel located in the upper diffuser plate. The return channel with the return outlet is configured to be capable of coupling with the fluid return conduit of the heat exchanger. A bottom diffuser plate is coupled to the top diffuser plate. [Selection diagram] Fig. 1

Description

Embodiments of the present disclosure generally relate to processing chambers such as plasma chemical vapor deposition (PECVD) chambers. More specifically, embodiments of the present disclosure relate to gas distribution assemblies for processing chambers.

Chemical vapor deposition (CVD) and plasma chemical vapor deposition (PECVD) are typically used to deposit thin films on substrates such as flat panel displays or transparent substrates for semiconductor wafers. CVD and PECVD are usually achieved by introducing a precursor gas or mixed gas into a vacuum chamber that includes the substrate. The precursor gas or mixed gas is typically guided downward through a gas diffuser located near the top of the chamber. The diffuser plate is placed above the substrate placed on the support heated for a short distance such that the diffuser and the precursor gas or mixed gas are heated by the radiant heat from the substrate support. During PECVD, the precursor gas or mixed gas in the chamber is energized (eg, excited) by applying RF power from one or more radio frequency (RF) sources connected to the chamber to the chamber. Can be plasma. The excited gas or mixed gas reacts to form a layer of material on the surface of the substrate placed on top of the heated substrate support. Volatile by-products produced during the reaction are expelled from the chamber through the exhaust system.

Flat panels treated by CVD and PECVD processing are typically large and often exceed 370 mm x 470 mm. Therefore, a large gas diffuser plate (or gas distribution plate) is utilized and a uniform process on a relatively large size flat panel compared to the gas diffuser plates used for processing 200 mm and 300 mm semiconductor wafers. A gas stream is provided. Since the gas diffuser plate is large and is heated only by the radiant heat from the substrate support and the excited plasma, the temperature distribution of the gas diffuser plate is not uniform, and film deposition or uneven film etching of non-uniform thickness. Occurs.

Therefore, improvement of the gas distribution assembly is needed to improve the uniformity of the deposited or etched film.

In one embodiment, a diffuser is provided. The diffuser includes an upper diffuser plate having an upstream surface and a downstream surface, and a plurality of first gas passage sections arranged in the upper diffuser plate. Each first gas passage is adjacent to at least one fluid channel located in the upper diffuser plate. Each fluid channel is connected to a supply channel that is located in the upper diffuser plate and has a supply inlet configured to be coupled to the fluid supply conduit of the heat exchanger. Each fluid channel is connected to a return channel located in the upper diffuser plate. The return channel with the return outlet is configured to be capable of coupling with the fluid return conduit of the heat exchanger. A bottom diffuser plate is coupled to the top diffuser plate. The bottom diffuser plate has an upstream surface and a downstream surface.

In another embodiment, a diffuser is provided. The diffuser includes an upper diffuser plate having an upstream surface and a downstream surface, and a plurality of first gas passage sections arranged in the upper diffuser plate. Each first gas passage is adjacent to at least one fluid channel located in the upper diffuser plate. Each fluid channel is connected to one of a supply channel and a supply bypass channel located in the upper diffuser plate. The supply channel has a supply inlet configured to be coupled to the fluid supply conduit of the heat exchanger. The supply bypass channel is fluid connected to the supply channel. Each fluid channel is connected to one of a return channel and a return bypass channel located in the upper diffuser plate. The return channel has a return outlet that is configured to be capable of coupling with the fluid return conduit of the heat exchanger. The return bypass channel is fluid connected to the return channel. A bottom diffuser plate is coupled to the top diffuser plate. The bottom diffuser plate has an upstream surface and a downstream surface.

In yet another embodiment, a chamber is provided. The chamber includes a support assembly and a radio frequency (RF) power supply coupled to the diffuser. The diffuser is located facing the support assembly. The diffuser includes an upper diffuser plate having an upstream surface and a downstream surface, and a plurality of first gas passage sections arranged in the upper diffuser plate. Each first gas passage is adjacent to at least one fluid channel located in the upper diffuser plate. Each fluid channel is connected to a supply channel that is located in the upper diffuser plate and has a supply inlet configured to be coupled to the fluid supply conduit of the heat exchanger. Each fluid channel is connected to a return channel located in the upper diffuser plate. The return channel with the return outlet is configured to be capable of coupling with the fluid return conduit of the heat exchanger. A bottom diffuser plate is coupled to the top diffuser plate. The bottom diffuser plate has an upstream surface and a downstream surface.

A more specific description of the present disclosure briefly summarized above can be made by reference to embodiments, some of which are attached, so that the above features of the present disclosure can be understood in detail. Shown in the drawing. However, it should be noted that the accompanying drawings show only exemplary embodiments and therefore should not be considered limiting the scope of the present disclosure, and other equally valid embodiments may be acceptable.

It is schematic cross-sectional view of one Embodiment of plasma chemical vapor deposition by Embodiment. FIG. 5 is a partial schematic cross-sectional view of an exemplary diffuser according to an embodiment. It is a bottom sectional view of an exemplary diffuser according to an embodiment. It is a reverse bottom perspective view of the upper diffuser plate by embodiment. FIG. 5 is an enlarged reverse cross-sectional view of an upper diffuser plate according to an embodiment. It is a reverse bottom perspective view of the upper diffuser plate by embodiment. FIG. 5 is an enlarged reverse cross-sectional view of an upper diffuser plate according to an embodiment.

For ease of understanding, the same reference numbers were used to indicate the same elements that are common to multiple figures, where possible. It is envisioned that the components and features of one embodiment may be beneficially incorporated into other embodiments without further description.

The embodiments described herein provide a gas distribution assembly that improves the uniformity of deposited or etched membranes. Each of the gas distribution assemblies is one of a unidirectional and bidirectional flow of fluid through the diffuser so that excess heat is removed and / or heat is provided to the diffuser to maintain the temperature of the given diffuser. Including one. By maintaining the diffuser 105 at a predetermined diffuser temperature regardless of the intensity of the plasma during the treatment and the heat radiated from the substrate support, the uniformity of film deposition and film etching is improved.

FIG. 1 is a schematic cross-sectional view of an embodiment of a Plasma Chemical Vapor Deposition (PECVD) Chamber 100 available from Aplite Materials, Inc., Santa Clara, CA. It is understood that the system described below is an exemplary chamber and that other chambers, including chambers from other manufacturers, may be used with or modified to achieve it with aspects of the present disclosure. Will be done. The chamber 100 includes a chamber body 102, a substrate support assembly 104, and a gas distribution assembly 106. The gas distribution assembly 106 is located opposite the substrate support assembly 104 and defines a processing space 108 between them.

The substrate support assembly 104 is at least partially located within the chamber body 102. The board support assembly 104 supports the board 110 during processing. The board support assembly 104 includes a board support 112. The substrate support 112 has a lower surface 114 for mounting the stem 118 and an upper surface 116 for supporting the support 110. The stem 118 facilitates transfer of the substrate support assembly 104 to or from the chamber 100 through the processing position of the substrate support assembly 104 (shown) and the slit valve 122 of the chamber body 102 (shown). Combined with a lift system 120 that moves between and.

In one embodiment that can be combined with other embodiments described herein, the resistor element located on the substrate support is coupled to a source such as a power source that controlsally heats the substrate support 112. Will be done. In another embodiment that can be combined with other embodiments described herein, at least one fluid channel (not shown) coupled to the heat exchanger 124 is at the inlet of at least one fluid channel. It is connected to at least one fluid channel via a connected support supply conduit 126 and via a support return conduit 128 that is connected to the outlet of at least one fluid channel. The heat exchanger 124 circulates the fluid through the substrate support 112 so that excess heat is removed and / or heat is provided to the substrate support 112 to maintain a predetermined support temperature. The predetermined support temperature can be set to a temperature based on processing parameters such that the uniform temperature distribution of the substrate 110 is maintained independent of the intensity of the plasma during processing. The fluid may include a material capable of maintaining a temperature of about 50 degrees Celsius to about 450 degrees Celsius.

The gas distribution assembly 106 includes a diffuser 105 suspended from a backing plate 103 by a hanger plate 107. The plurality of gas passages 109 are formed through the diffuser 105 to allow a uniformly predetermined distribution of gas to pass through the diffuser 105 into the processing space 108. The hanger plate 107 maintains the diffuser 105 and the backing plate 103 in a distant relationship, thereby defining a plenum 111 between them. The backing plate 103 includes a gas inlet passage 113 coupled to a manifold 115 that can be coupled to one or more gas sources 117. The plenum 111 flows uniformly across the width of the gas distribution assembly 106 through the plurality of gas passages 109 so that the gas is uniformly provided on the diffuser 105 and the gas is uniformly flowed in the processing space 108. Make it possible.

The gas distribution assembly 106 is coupled to a radio frequency (RF) power supply 119, which is used to generate plasma for processing the substrate 110. The substrate support assembly 104 typically supplies RF power to the gas distribution assembly 106 by the RF power supply 119 to provide a capacitive coupling between the diffuser 105 and the substrate support 112. When RF power is supplied to the diffuser 105, an electric field is generated between the diffuser 105 and the substrate support 112, so that gas atoms existing in the processing space 108 between the substrate support 112 and the diffuser 105 are generated. Is ionized and emits electrons. During the process, the heat generated from the intensity of the plasma and the heat radiated to the diffuser 105 from the substrate support 112 are non-uniform and may create hot and cold zones throughout the diffuser 105. The gas distribution assembly 106 includes a system 101 for maintaining a predetermined diffuser temperature that is uniform across the diffuser 105 regardless of the intensity of the plasma being processed and the heat radiated from the substrate support 112. By maintaining the diffuser 105 at a predetermined diffuser temperature regardless of the intensity of the plasma during the treatment and the heat radiated from the substrate support 112, the uniformity of film deposition and film etching is improved.

The system 101 includes at least a plurality of fluid channels 121. Each of the fluid channels 121 has a channel inlet (shown in FIG. 2C-2F) coupled to at least one of a supply channel (shown in FIG. 2C-2F) and a supply bypass channel (shown in FIGS. 2E and 2F). Each of the fluid channels 121 has a channel outlet (shown in FIG. 2C-2F) coupled to at least one of a return channel (shown in FIG. 2C-2F) and a return bypass channel (shown in FIGS. 2E and 2F). The heat exchanger 123 is connected to the supply channel via a fluid supply conduit 125 connected to the inlet of the supply channel (shown in FIGS. 2C and 2E). The heat exchanger 123 is connected to the return channel via a fluid return conduit 127 connected to the outlet of the return channel (shown in FIGS. 2C and 2E). The heat exchanger 123 circulates the fluid through the fluid channel 121 so that excess heat is removed and / or heat is provided to the diffuser 105 to maintain a predetermined diffuser temperature. The predetermined diffuser temperature can be set to a temperature based on processing parameters such that the uniform temperature distribution of the diffuser 105 is independent of the intensity of the plasma being processed and the heat radiated from the substrate support 112. The fluid may include a material capable of maintaining a temperature of about 50 degrees Celsius to about 450 degrees Celsius.

The controller 130 is coupled to the chamber 100 and is configured to control aspects of the chamber 100 during processing. The controller 130 may include a central processing unit (CPU) (not shown), a memory (not shown), and a support circuit (or I / O) (not shown). The CPU may be one of any form of computer processor and hardware (eg, motors and other hardware) used in industrial settings to control various processes, and may be a process (eg, eg, motor and other hardware). The flow rate of the fluid) can be monitored. Memory (not shown) is connected to the CPU and is easily accessible, such as random access memory (RAM), read-only memory (ROM), floppy disks, hard disks, or local or remote digital storage in any other form. It may be one or more of the available memory. Software instructions and data for instructing the CPU can be encoded and stored in memory. Auxiliary circuits (not shown) are also connected to the CPU to assist the processor in the traditional way. Auxiliary circuits may include conventional caches, power supplies, clock circuits, input / output circuits, subsystems and the like. A readable program (or computer instruction) by controller 130 determines which tasks can be performed by chamber 100. The program may be software readable by the controller 130 and may include, for example, instructions for monitoring and controlling a predetermined diffuser temperature of the diffuser 105.

FIG. 2A is a partial schematic cross-sectional view of the exemplary diffuser 105, and FIG. 2B is a bottom sectional view of the exemplary diffuser 105. The diffuser 105 is composed of a thickness 242 that maintains sufficient flatness in the entire hanger plate 107 so as not to adversely affect the processing of the substrate. In one embodiment that can be combined with other embodiments described herein, the thickness 242 of the diffuser 105 is between about 0.8 inches and about 2.0 inches. The diffuser 105 may be circular for manufacturing semiconductor wafers, or may be polygonal such as a rectangle for manufacturing flat panel displays.

The diffuser 105 includes an upper diffuser plate 202 that includes an upstream surface 206 and a downstream surface 208 facing the backing plate 103. In one embodiment that can be combined with other embodiments described herein, one of the downstream surfaces 208 of the diffuser 105 is upstream of the bottom diffuser plate 204 including the downstream surface 212 facing the substrate support 112. At least one of casting, brazing, forging, hot hydrostatic pressing and sintering is performed on the surface 210. The top diffuser plate 202 has a thickness of 244 and the bottom diffuser plate 204 has a thickness of 246. Each gas passage 109 includes a first gas passage section 248 in the upper diffuser plate 202 and a second gas passage section 250 in the bottom diffuser plate 204. In one embodiment that can be combined with other embodiments described herein, each of the fluid channels 121 adjacent to the orifice hole 216 is a distance 240 from the orifice hole 216. In another embodiment that can be combined with other embodiments described herein, each of the fluid channels 121 has a width of 238 and a height of 236. In another embodiment that can be combined with other embodiments described herein, each of the fluid channels 121 is U-shaped or V-shaped.

As shown in FIG. 2C, which is an inverted bottom perspective view of the upper diffuser plate 202 of the exemplary diffuser 105, and FIG. 2D, which is an enlarged inverted sectional view of the upper diffuser plate 202, each of the fluid channels 121 is at least. It is located adjacent to one first gas passage section 248. The fluid channel 121 is formed on the downstream surface 208 of the upper diffuser plate 202. Each first gas passage section 248 is located on the upper diffuser plate 202. As shown in FIG. 2A, each first gas passage section 248 is defined by a first bore 214 coupled to an orifice hole 216, and each second gas passage section 250 is an orifice in the upper diffuser plate 202. It is defined in the bottom diffuser plate 204 by a second bore 218 coupled to the hole 216. In one embodiment shown in FIGS. 2C and 2D having a unidirectional flow structure, each of the fluid channels 121 has a channel inlet 213 coupled to a supply channel 207 and a channel outlet 215 coupled to a return channel 209. Have. The supply channel 207 includes an inlet connected to the heat exchanger 123 via the fluid supply conduit 125 and an outlet 205 connected to the heat exchanger 123 via the fluid return conduit 127. The heat exchanger 123 circulates the fluid through the fluid channel 121 in a unidirectional flow, maintaining the diffuser 105 at a predetermined diffuser temperature. In one embodiment that can be combined with other embodiments described herein, the system 101 includes a plurality of thermocouples 251 coupled to the controller 130 to determine the temperature of the diffuser 105. The controller 130 coupled to the thermocouple 251 and the heat exchanger 123 can operate to monitor and control the circulation and temperature of the fluid entering the supply channel 207.

The first bore 214, the orifice hole 216, and the second bore 218 combine to form a passage through the diffuser 105. The first bore 214 extends a first length 230 from the upstream surface 206 of the upper diffuser plate 202 to the bottom 220. The bottom 220 of the first bore 214 is chamfered, whether tapered or beveled, to minimize flow restrictions as gas flows from the first bore 214 into the orifice hole 216. It may be rounded or rounded. The first bore 214 typically has a diameter of about 0.093 inches to about 0.218 inches, and in one embodiment has a diameter of about 0.156 inches.

The second bore 218 is formed in the bottom diffuser plate 204 and extends from the downstream surface 212 to a third length 234 of about 0.10 inches to about 2.0 inches. Preferably, the third length 234 is between about 0.1 inch and about 1.0 inch. The diameter 226 of the second bore 218 is typically from about 0.1 inch to about 1.0 inch and may be flared at an angle of 224 from about 10 degrees to about 50 degrees. Preferably, the diameter 226 is between about 0.1 inch and about 0.5 inch and the angle 224 is between 20 and 40 degrees. The diameter 226 of the second bore 218 refers to the diameter that intersects the downstream surface 212. The surface area of the second bore 218 is between about 0.05 square inches and about 10 square inches, preferably between about 0.05 square inches and about 5 square inches. 214

An example of a diffuser 105 used to process a 1500 mm × 1850 mm substrate has a 0.250 inch diameter 226 and a second bore 218 at an angle of about 22 degrees 224. The distance 228 between the rims 252 of the adjacent second bore 218 is between about 0 inches and about 0.6 inches, preferably between about 0 inches and about 0.4 inches. The diameter 254 of the first bore 214 is usually, but is not limited to, at least 226 or less in diameter of the second bore 218. The bottom 222 of the second bore 218, whether tapered or beveled, to minimize pressure loss of gas flowing out of the orifice hole 216 and flowing into the second bore 218. It may be chamfered or rounded.

The orifice hole 216 typically joins the bottom 220 of the first bore 214 and the bottom 222 of the second bore 218. The orifice holes 216 typically have a diameter of about 0.01 inches to about 0.3 inches, preferably about 0.01 inches to about 0.1 inches, typically from about 0.02 inches to about. It has a second length of 232 of 1.0 inches, preferably about 0.02 inches to about 0.5 inches. The second length 232 and diameter (or other geometric attribute) of the orifice hole 216 is the main back pressure in the plenum 111 that promotes a uniform distribution of gas throughout the upstream surface 206 of the upper diffuser plate 202. Responsible. The orifice hole 216 is typically configured uniformly in the plurality of gas passages 109, but the restriction through the orifice hole 216 passes through one region of the diffuser 105 as compared to another region. It may be configured differently among the plurality of gas passages 109 to promote more gas flow. For example, the orifice hole 216 is closer to the wall of the chamber body 102, in the gas passage 109 of the diffuser 105, so that more gas flows through the end face of the diffuser 105 and the deposition rate on the outer periphery of the substrate 110 increases. May have a longer diameter and / or a shorter second length 232. The thickness of the diffuser plate is between about 0.8 inches and about 3.0 inches, preferably between about 0.8 inches and about 2.0 inches.

As shown in FIG. 2E, which is a reverse bottom perspective view, and FIG. 2F, which is an enlarged reverse cross-sectional view, the upper diffuser plate 202 has a bidirectional flow structure. The bidirectional flow structure includes a first portion of a plurality of fluid channels 121 having a channel inlet 211 coupled to the supply channel 207 and a channel outlet 249 coupled to the return channel 209. The bidirectional flow structure includes a second portion of a plurality of fluid channels 121 having a channel inlet 211 coupled to the supply bypass channel 217 and a channel outlet 249 coupled to the return bypass channel 219. The supply bypass channel 217 is coupled to the supply channel 207 by the supply transmission channel 221. The return bypass channel 219 is coupled to the return channel 209 by a return transmission channel 223. The fluid channel 121 in the first part and the fluid channel 121 in the second part alternate due to the bidirectional flow of fluid. The heat exchanger 123 passes through the supply channel 207, the first portion of the plurality of fluid channels 121, and the return channel 209, and through the supply bypass channel 217, the second portion of the plurality of fluid channels 121, and the return bypass channel 219. The fluid is circulated to maintain the diffuser 105 at a predetermined diffuser temperature.

In summary, gas partitioning assemblies that improve the uniformity of deposited or etched membranes are described herein. Each of the gas distribution assemblies is one of a unidirectional and bidirectional flow of fluid through the diffuser so that excess heat is removed and / or heat is provided to the diffuser to maintain the temperature of the given diffuser. Including one. By maintaining the diffuser at a predetermined diffuser temperature regardless of the intensity of the plasma during the treatment and the heat radiated from the substrate support, the uniformity of film deposition and film etching is improved.

Although the above description is intended for the embodiments of the present disclosure, other embodiments and further embodiments of the present disclosure may be devised without departing from the basic scope of the present disclosure. The scope is determined by the following claims.

Claims (15)

It ’s a diffuser,
With an upper diffuser plate with upstream and downstream surfaces;
A plurality of first gas passage sections arranged in the upper diffuser plate, each first gas passage adjacent to at least one fluid channel arranged in the upper diffuser plate.
Each fluid channel is connected to a supply channel located in the upper diffuser plate, which has a supply inlet configured to be coupled to the fluid supply conduit of the heat exchanger; Each fluid channel is connected to a return channel located in the upper diffuser plate, the return channel having a plurality of first outlets configured to be coupled to the fluid return conduit of the heat exchanger. With the gas passage section of;
A diffuser comprising a bottom diffuser plate coupled to an upper diffuser plate and having upstream and downstream surfaces. 1 Described diffuser. The diffuser of claim 2, wherein each orifice hole is adjacent to at least one fluid channel located in the upper diffuser plate. The diffuser according to claim 3, wherein each fluid channel adjacent to the orifice hole is a first distance from the orifice hole. When the heat exchanger is coupled with the supply and return channels, the fluid is circulated from the fluid supply conduit through the supply channel, each fluid channel, the return channel, and through the fluid return conduit to the heat exchanger. The diffuser according to claim 1, which is operable. The diffuser according to claim 5, wherein a controller coupled to the heat exchanger can operate to control the circulation of the fluid to maintain a predetermined diffuser temperature. The diffuser according to claim 6, wherein a thermocouple arranged in the upper diffuser plate is coupled to the controller. The diffuser according to claim 1, wherein the downstream surface of the upper diffuser plate is formed with respect to the upstream surface of the bottom diffuser plate at least one of casting, brazing, forging, hot hydrostatic pressing and sintering. .. The diffuser according to claim 1, which can be arranged in the processing chamber so as to face the substrate support arranged in the processing chamber. It ’s a diffuser,
With an upper diffuser plate with upstream and downstream surfaces;
A plurality of first gas passage sections arranged in the upper diffuser plate, each first gas passage adjacent to at least one fluid channel arranged in the upper diffuser plate.
Each fluid channel is connected to one of a supply channel and a supply bypass channel located in the upper diffuser plate so that the supply channel can be coupled to the fluid supply conduit of the heat exchanger. It has a supply inlet, the supply bypass channel is fluid connected to the supply channel; and each fluid channel is coupled to one of the return and return bypass channels located in the upper diffuser plate. With a plurality of first gas passage sections in which the return channel has a return outlet configured to be coupled to the fluid return conduit of the heat exchanger and the return bypass channel is fluid connected to the return channel;
A diffuser comprising a bottom diffuser plate coupled to an upper diffuser plate and having upstream and downstream surfaces. It ’s a chamber,
Support assembly; and includes a radio frequency (RF) power supply coupled to a diffuser located opposite the support assembly, and the diffuser is:
With an upper diffuser plate with upstream and downstream surfaces;
Multiple first gas passage sections located in the upper diffuser plate, each first gas passage adjacent to at least one fluid channel located in the upper diffuser plate;
Each fluid channel is connected to a supply channel that is located in the upper diffuser plate and has a supply inlet configured to be coupled to the fluid supply conduit of the heat exchanger; and each fluid channel is on top. With multiple first gas passage sections connected to a return channel with a return outlet configured to be coupled to the fluid return conduit of the heat exchanger, located in the diffuser plate;
A chamber comprising a bottom diffuser plate with upstream and downstream surfaces coupled to an upper diffuser plate. When the heat exchanger is coupled with the supply and return channels, the fluid is circulated from the fluid supply conduit through the supply channel, each fluid channel, the return channel, and through the fluid return conduit to the heat exchanger. The chamber according to claim 11, which is operational. 12. The chamber of claim 12, wherein a controller coupled to a heat exchanger can operate to control fluid circulation to maintain a predetermined diffuser temperature. 13. The chamber of claim 13, wherein a thermocouple located in the upper diffuser plate is coupled to the controller. 11. The chamber of claim 11, wherein the downstream surface of the top diffuser play is at least one of casting, brazing, forging, hot hydrostatic press and sintering with respect to the upstream surface of the bottom diffuser plate. ..

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