Dome-shaped chamber for generating in-situ cleaning plasma

Abstract

A process chamber includes a first portion having a dome and a second portion. The dome comprises a ceramic material and is elliptical. A susceptor for processing a substrate is arranged in the second portion. The showerhead is disposed at a base of the dome between the first portion and the second portion. An injector comprising a ceramic material is mounted on the dome to inject a process gas and a cleaning gas during substrate processing and during processing chamber cleaning, respectively. A coil is disposed around a portion of the dome. An RF generator supplies RF power to the coil to generate plasma within the dome during substrate processing and during cleaning. The controller controls the temperatures of the susceptor and the showerhead at respective predetermined temperatures within a predetermined range during substrate processing and cleaning.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 412,152, filed on September 30, 2022. The entire disclosure of the above application is incorporated herein by reference. Technical Field

[0002] The present disclosure relates generally to substrate processing systems and, more particularly, to a dome-shaped chamber for generating an in-situ cleaning plasma. Background Art

[0003] The background description provided here is for the purpose of generally presenting the background of the present disclosure. The work of the currently designated inventors within the scope described in this background section and aspects of the specification that were not determined to be prior art at the time of filing the application are neither explicitly nor implicitly admitted to be prior art against the present disclosure.

[0004] Substrate processing systems typically include one or more processing chambers. Each processing chamber surrounds a susceptor on which a substrate, such as a semiconductor wafer, is disposed during processing. A gas delivery system may be used to introduce a process gas mixture containing one or more precursors into the processing chamber to deposit a film on the substrate or to etch the substrate. A plasma may be energized in the processing chamber.

[0005] Some substrate processing systems use atomic layer deposition (ALD) processes to deposit materials on substrates. ALD is a thin film deposition method that performs chemical processes in sequence to deposit a thin film on a substrate surface. ALD uses at least two chemical species called precursors (reactants) to react with the substrate surface one precursor at a time in a sequential, self-limiting manner. Through repeated exposure to different precursors, a thin film is gradually deposited on the surface of the substrate. Summary of the invention

[0006] A substrate processing system includes a processing chamber, a pedestal, a showerhead, an injector, a coil, a radio frequency (RF) generator, and a controller. The processing chamber includes a first portion and a second portion. The first portion includes a dome. The dome includes a ceramic material and is elliptical. The pedestal is configured to process a substrate arranged in the second portion of the processing chamber. The showerhead is arranged at the base of the dome between the first portion and the second portion of the processing chamber. The injector includes the ceramic material and is mounted on the dome. The injector is configured to inject a process gas and a cleaning gas during substrate processing and during cleaning of the processing chamber, respectively. The coil is arranged around a portion of the dome. The RF generator is configured to supply RF power to the coil to generate plasma in the dome during substrate processing and during cleaning of the processing chamber. The controller is configured to control the temperature of the pedestal and the showerhead to a corresponding predetermined temperature within a predetermined range during substrate processing and during cleaning of the processing chamber.

[0007] In additional features, the predetermined range is ±0-1% of the respective predetermined temperatures.

[0008] In additional features, the controller is configured to maintain the temperature of the pedestal and the showerhead at the respective predetermined temperatures during processing of the substrate and during cleaning of the chamber.

[0009] In additional features, the ceramic material is alumina.

[0010] In an additional feature, the inner wall of the dome is coated with a second material that is heat and corrosion resistant.

[0011] In additional features, the second material is yttrium oxide.

[0012] In additional features, the substrate processing system further includes a housing disposed around the dome and the coil, the housing being attached to a periphery of the showerhead. The housing includes a plurality of fans disposed in an azimuthally symmetrical manner along a sidewall thereof.

[0013] In additional features, the substrate processing system further includes a gas delivery system configured to supply the cleaning gas through the injector at a flow rate that inhibits particles ejected from the susceptor from contaminating the showerhead during the cleaning of the processing chamber.

[0014] In additional features, the substrate processing system further includes a gas delivery system configured to supply an inert gas directly to the showerhead to inhibit particles ejected from the pedestal from contaminating the showerhead during the cleaning of the processing chamber.

[0015] In additional features, the substrate processing system further includes a gas delivery system configured to supply an inert gas directly to the showerhead to prevent the cleaning gas from stagnating in the showerhead after the cleaning of the processing chamber.

[0016] In additional features, the substrate processing system further comprises a gas delivery system. The showerhead comprises a first plenum and a second plenum. The first plenum is configured to filter ions from the plasma and deliver radicals from the plasma to the second portion of the processing chamber. The second plenum is configured to (i) directly receive a precursor from the gas delivery system and supply the precursor to the second portion of the processing chamber during the substrate processing, and (ii) directly receive an inert gas from the gas delivery system during the cleaning of the processing chamber.

[0017] In additional features, the coil includes a plurality of turns. The plurality of turns around the dome and the positions of the turns distribute ions and heat loads from the plasma throughout the dome.

[0018] In additional features, the pedestal includes a heater. The substrate processing system further includes a fluid delivery system configured to supply a coolant to the pedestal and the showerhead. The controller is configured to control the heater and the flow of the coolant to maintain the temperature of the showerhead and the pedestal within the predetermined range of the respective predetermined temperatures during the substrate processing and during the cleaning of the processing chamber.

[0019] In additional features, the pedestal includes a heater. The substrate processing system further includes a fluid delivery system configured to supply a coolant to the pedestal and the showerhead. The controller is configured to control the heater and the flow of the coolant to maintain the temperature of the pedestal and the showerhead at the respective predetermined temperatures during the substrate processing and during the cleaning of the processing chamber.

[0020] In yet further features, a method for cleaning a processing chamber comprising a pedestal and a showerhead and configured to process a substrate comprises: during the cleaning of the processing chamber, controlling the temperature of the pedestal and the showerhead within a predetermined range of respective predetermined temperatures used during processing of the substrate. The method comprises supplying a cleaning gas to an elliptical dome of the processing chamber through an injector, the injector being mounted on the elliptical dome, the elliptical dome and the injector comprising a ceramic material. The method comprises generating a plasma in the elliptical dome by supplying radio frequency (RF) power to a coil disposed around the elliptical dome. The method comprises controlling the flow of the cleaning gas through the injector to inhibit contamination of the showerhead by particles ejected from the pedestal.

[0021] In additional features, the predetermined range is ±0-1% of the corresponding predetermined temperature.

[0022] In additional features, the method further comprises maintaining the temperatures of the pedestal and the showerhead at the respective predetermined temperatures during processing of the substrate and during cleaning of the chamber.

[0023] In additional features, the method further includes spraying an inner wall of the elliptical dome with a second material that is heat and corrosion resistant.

[0024] In additional features, the ceramic material is aluminum oxide and the second material is yttrium oxide.

[0025] In additional features, the method further includes: enclosing the elliptical dome and the coil in a housing attached to a perimeter of the showerhead; and cooling the elliptical dome using a plurality of fans arranged in an azimuthally symmetrical manner along a sidewall of the housing.

[0026] In additional features, the method further includes supplying an inert gas directly to the showerhead to further inhibit the contamination of the showerhead by the particles.

[0027] In additional features, the method further includes flowing an inert gas through the showerhead to prevent stagnation of the cleaning gas in the showerhead.

[0028] In additional features, the method further comprises arranging turns of the coil around the elliptical dome to distribute ions and heat loads from the plasma throughout the elliptical dome.

[0029] In additional features, the method further includes, after the cleaning of the processing chamber: stopping the supply of the cleaning gas and the RF power; controlling the temperature of the susceptor and the showerhead within the predetermined range of the corresponding predetermined temperatures; and supplying process gas to the elliptical dome through the injector to process a second substrate in the processing chamber.

[0030] In additional features, the method further comprises supplying a precursor directly to the showerhead.

[0031] In additional features, the method further comprises exciting a second plasma in the elliptical dome by supplying the RF power to the coil; and filtering ions from the second plasma and transmitting radicals from the second plasma to the second substrate.

[0032] In additional features, the method further includes supplying a coolant through the pedestal and the showerhead to maintain the temperature of the showerhead and the pedestal within the predetermined range of the respective predetermined temperatures during the processing of the second substrate in the processing chamber.

[0033] In additional features, the method further comprises supplying a coolant through the pedestal and the showerhead to maintain the temperatures of the pedestal and the showerhead at the respective predetermined temperatures during the processing of the second substrate in the processing chamber.

[0034] Further scope of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0036] Figure 1 An example of a substrate processing system including a dome-shaped processing chamber for generating an in-situ cleaning plasma during substrate processing and chamber cleaning according to the present disclosure is shown;

[0037] Figure 2 An example of a housing containing a cooling fan and surrounding a Figure 1 A process chamber dome of a substrate processing system;

[0038] Figure 3 It further shows that Figure 1 An example of a portion of a gas delivery system in a substrate processing system; and

[0039] Figure 4 Shows Figure 1 A flow chart of a method of processing a substrate and cleaning a process chamber using an in-situ cleaning plasma while maintaining a constant pedestal and showerhead temperature during substrate processing and cleaning.

[0040] Among the drawings, reference numerals may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION

[0041] Some substrate processing systems (also referred to as tools) contain up to four processing chambers that are used to deposit materials on substrates using a deposition process. The processing chambers are periodically cleaned using a cleaning process during which substrate production is suspended. That is, the cleaning process is performed separately and differently from the deposition process. For example, the cleaning process is typically performed during a periodic preventive maintenance process after many cycles of the deposition process to clean the processing chambers and their components.

[0042] In a typical cleaning process for cleaning a process chamber, a remote plasma source (RPS) disposed outside the process chamber is used to generate a cleaning plasma. For example, the RPS is located in the center between multiple process chambers, and the cleaning plasma from the RPS is supplied to each process chamber to clean the process chamber. There are various problems with using externally generated cleaning plasma to clean multiple process chambers.

[0043] For example, it is necessary to set multiple components of the processing chamber (such as the showerhead and the pedestal) to different temperatures for the cleaning process and the deposition process for processing the substrate in the processing chamber. For example, the temperatures of the showerhead and the pedestal are usually maintained at 50 degrees Celsius and 550 degrees Celsius, respectively. These temperatures can be different depending on the process (such as the recipe) used to process the substrate in the processing chamber. During the cleaning process, the temperatures of the showerhead and the pedestal are usually maintained at 150 degrees Celsius and 400 degrees Celsius, respectively.

[0044] Typically, the susceptor temperature is lowered to a temperature lower than the temperature used during substrate processing (e.g., from 550 degrees Celsius to 400 degrees Celsius) before performing a cleaning process, because at higher temperatures (e.g., above 450 degrees Celsius), the susceptor may generate particles from the susceptor surface that contaminate the showerhead. Therefore, in order to minimize particles generated from the susceptor surface that contaminate the showerhead, the susceptor temperature is typically lowered to a temperature lower than the temperature used during substrate processing (e.g., from 550 degrees Celsius to 400 degrees Celsius) before performing a cleaning process.

[0045] After the cleaning process, the showerhead temperature is lowered (e.g., from 150 degrees Celsius to 50 degrees Celsius) and the susceptor temperature is raised (e.g., from 400 degrees Celsius to 550 degrees Celsius). The different temperature settings used during substrate processing and cleaning processes require additional time to allow the temperature of the components to transition between the temperatures required during deposition and the temperatures required during cleaning. The additional time required to allow these temperature transitions to occur reduces the throughput time of the processing chamber.

[0046] Furthermore, the contamination problem is exacerbated because the cleaning plasma is supplied at a location in the process chamber between the showerhead and the pedestal. Due to the location where the cleaning plasma is supplied and due to the typical conical shape of the plasma chamber, particles generated from the pedestal surface are transported toward the showerhead and contaminate it.

[0047] In addition, the movement of the remote cleaning plasma in the process chamber requires a longer time to clean the showerhead during cleaning, but still does not effectively clean the showerhead (i.e., the etching rate at the showerhead is less than the etching rate at the pedestal). Therefore, the cleaning process using the remote cleaning plasma exacerbates the showerhead particle contamination that occurs during the cleaning process. Therefore, before the deposition process is restarted in the process chamber, the showerhead needs to undergo a requalification process after the cleaning process. The requalification period performed on all four process chambers of the tool further reduces the production time of the process chamber.

[0048] The present disclosure provides an in-situ plasma-based cleaning process that solves the above-mentioned problems. The in-situ plasma-based cleaning process of the present disclosure is also performed separately and differently from the ALD process performed, for example, in the processing chamber to process the substrate. For example, the cleaning process is usually performed during a preventive maintenance program that is performed regularly after many cycles of processing the substrate in the processing chamber to clean the processing chamber and its components.

[0049] Specifically, in an in-situ plasma-based cleaning process, instead of supplying a remotely generated cleaning plasma to the processing chamber, the cleaning plasma is generated in situ in each processing chamber. In addition, the temperature of components such as showerheads and pedestals does not change between cleaning and deposition. During the cleaning process, the components are maintained at the same temperature used during substrate processing. At most, the temperature of the component may vary within a predetermined range (e.g., a narrow range of ±0-1%) between substrate processing and the cleaning process. For practical purposes, as long as the temperature remains within a predetermined range, the temperature of the component is considered to be uniform (i.e., substantially equal) during substrate processing and the cleaning process. Throughout this disclosure, unifying the temperature of a component during substrate processing and the cleaning process should be understood as controlling or maintaining the temperature of the component at a corresponding predetermined temperature within a predetermined range (e.g., ±0-1%). Below in Figure 4 The predetermined range will be explained in detail after the description of The cleaning process performed using the in-situ plasma generated in each processing chamber provides the following improvements.

[0050] The cleaning process performed using an in-situ plasma generated in each processing chamber provides the following improvements. By unifying the temperature of components used for the cleaning and deposition processes, the time normally required to switch between different temperature settings for these processes is eliminated. Eliminating the time required for temperature switching increases the production time of the processing chamber.

[0051] In addition, the cleaning plasma is generated in each processing chamber using the same hardware used to generate the plasma during the deposition process. Specifically, during the deposition process, the process gas is supplied by an injector located at the top of the processing chamber, and the plasma is excited in the processing chamber. During the cleaning process, the cleaning gas is supplied by the same injector located at the top of the processing chamber, and the cleaning plasma is excited in the processing chamber. The cleaning plasma first passes through the showerhead and cleans the showerhead first, and then reaches and cleans the pedestal. In other words, the etching rate at the showerhead is greater than the etching rate at the pedestal. Therefore, the cleaning process based on the in-situ plasma not only removes the remote plasma source, but also cleans the showerhead better than when using the remote cleaning plasma. Since the in-situ cleaning plasma cleans the showerhead better than when using the remote cleaning plasma, the cleaning process based on the in-situ cleaning plasma is also shorter in time than the cleaning process based on the remote plasma.

[0052] In addition, unifying component temperatures for cleaning and deposition processes requires that the susceptor be maintained at the same temperature during the cleaning process as during substrate processing (e.g., 550 degrees Celsius). High susceptor temperatures can generate particles on the susceptor surface, which can contaminate the showerhead. In-situ plasma-based cleaning processes mitigate (suppress) particle contamination of the showerhead by controlling (e.g., increasing) the flow rate of the cleaning gas flowing through the injector during the cleaning process.

[0053] In addition, cleaning gases tend to remain in the showerhead, which can contaminate and damage the showerhead. By supplying an inert gas (called a trickle) directly to the showerhead, the cleaning gas can be prevented from remaining (i.e., traces of the cleaning gas can be removed) in the showerhead. Therefore, there is no need to requalify the showerhead after the cleaning process, and the deposition process can be resumed for production immediately after the cleaning process. The processing chamber can also be ready for production immediately after the cleaning process because the temperature of the showerhead and the pedestal does not change (i.e., is consistent) between the deposition and cleaning processes. Since the in-situ plasma-based cleaning process eliminates the temperature conversion time and reduces particle contamination of the showerhead, the time spent on the in-situ plasma-based cleaning process is further reduced.

[0054] Thus, the in-situ plasma based cleaning process of the present disclosure eliminates the remote plasma source, cleans the showerhead better than a remote plasma based cleaning process, eliminates particle contamination of the showerhead, and increases process throughput time compared to using a remote plasma based cleaning process.

[0055] In-situ plasma based cleaning processes use different geometries and materials for the dome of the processing chamber and energize the plasma in the dome of the processing chamber compared to conventional processing chambers that use remote plasma in the cleaning process. The different geometries (described in detail below) optimize the movement of the plasma during deposition and cleaning. The different materials of the dome and the coatings applied to the inner surface of the dome reduce etching and corrosion of the inner surface of the dome due to the harsh chemical, thermal and electrical environments used during deposition and cleaning processes.

[0056] In addition, the injector of the processing chamber also includes a material different from that used in the injectors of conventional processing chambers based on remote plasma cleaning processes. The different materials show less etching and corrosion of the injectors due to the harsh environment used during deposition and cleaning. In addition, the present disclosure also provides a housing having an improved cooling effect on the dome and the RF coils disposed around the dome for plasma generation. These and other features of the present disclosure are described in detail below.

[0057] The content of this disclosure is organized as follows. In Part 1, reference is made to Figure 1 An example of a substrate processing system 100 including a dome-shaped processing chamber is shown and described. In Section 2, reference is made to Figure 1 and Figure 2 The design of the dome, coil and housing with fan is described in detail. In Part 3, Ref. Figure 1 and Figure 3 The controlled supply of clean and inert gases to mitigate showerhead contamination is described. In Section 4, reference Figure 4 Methods of processing substrates and cleaning plasma chambers according to the present disclosure are described. Part 1: Substrate handling systems

[0058] Figure 1 A substrate processing system 100 (also referred to as a tool) according to the present disclosure is shown. The substrate processing system 100 includes a processing chamber 103. The substrate processing system 100 may include multiple (e.g., four) processing chambers (also referred to as stations or processing modules) that are similar to the processing chamber 103 and include components similar to the components of the processing chamber 103. The processing chamber 103 is described below. Some components of the substrate processing system 100 described below may be shared by multiple processing chambers of the substrate processing system 100. Examples of components of the substrate processing system 100 shared by multiple processing chambers include a gas delivery system (element 130, element 170), an RF generation system (element 136), a fluid delivery system (element 180), a temperature controller (182), and a system controller (element 190).

[0059] The processing chamber 103 includes a dome 102, a showerhead 104, and a pedestal 112. The dome 102 will be described in detail below after describing the plasma generation. In short, the dome 102 is elliptical. Specifically, the shape of the dome 102 is a portion of an ellipse and has an elliptical profile. The shape of the dome is similar to an ellipse, wherein the bottom of the ellipse is removed along a horizontal plane. The dome 102 includes a ceramic material (e.g., alumina). The dome 102 is arranged above the showerhead 104 and attached to the showerhead 104. The pedestal 112 is arranged below the showerhead 104. The showerhead 104 separates the dome 102 and the pedestal 112.

[0060] The space defined by the inner wall of the dome 102 and the upper surface of the showerhead 104 may be referred to as the upper portion (or first portion) of the process chamber 103. The space defined by the lower surface of the showerhead 104 facing the substrate and the sidewalls 108 and the bottom wall 110 of the process chamber 103 may be referred to as the lower portion (or second portion) of the process chamber 103. The susceptor 112 is arranged in the lower portion of the process chamber 103 and is located below the showerhead 104. The showerhead 104 separates the upper portion and the lower portion of the process chamber 103.

[0061] The showerhead 104 is a double-gassing showerhead. The showerhead 104 comprises a metal (e.g., aluminum) or an alloy. The showerhead 104 comprises a planar base 105 and a cylindrical portion 107 extending vertically downward from the base 105. The base 105 is horizontal and parallel to a top surface 116 of the base 112 and a bottom wall 110 of the processing chamber 103. The base 105 extends radially outward at the top of the cylindrical portion 107. The base 105 extends radially outward from the outer diameter (OD) of the cylindrical portion 107 to form a flange 118. The flange 118 is fastened to a top plate (not shown) of the processing chamber 103. An O-ring (not shown) may be disposed between the flange 118 and the top plate to form a seal between the showerhead 104 and the top plate. The cylindrical portion 107 has an outer wall 109-1 and an inner wall 109-2. The inner wall 109-2 of the cylindrical portion 107 defines the hole 106 of the showerhead 104. The diameter of the hole 106 is equal to the diameter of the inner wall 109-2 of the cylindrical portion 107 of the showerhead 104 (ie, the inner diameter or ID of the cylindrical portion 107).

[0062] The side wall 108 of the process chamber 103 is attached to the bottom of the cylindrical portion 107 of the showerhead 104. The side wall 108 is perpendicular to the base 105 of the showerhead 104 and extends vertically downward from the bottom of the outer wall 109-1 of the cylindrical portion 107 of the showerhead 104. The bottom wall 110 of the process chamber 103 is parallel to the base 105 of the showerhead 104, perpendicular to the side wall 108 of the process chamber 103, and attached to the side wall 108 of the process chamber 103.

[0063] During processing, the substrate 114 is disposed on the top surface 116 of the pedestal 112. The top surface 116 of the pedestal 112 is flat and parallel to the base 105 of the showerhead 104 and to the bottom wall 110 of the processing chamber 103. Therefore, when the substrate 114 is disposed on the top surface 116 of the pedestal 112, the substrate 114 is parallel to the top surface 116 of the pedestal 112, the base 105 of the showerhead 104, and the bottom wall 110 of the processing chamber 103. The ID of the cylindrical portion 107 of the showerhead 104 (i.e., the diameter of the inner wall 109-2 of the showerhead 104) is greater than the OD of the top surface 116 of the pedestal 112. The ID of the cylindrical portion 107 of the showerhead 104 (i.e., the diameter of the inner wall 109-2 of the showerhead 104) is also greater than the OD of the substrate 114.

[0064] The actuator 122 driven by the motor 120 can move the pedestal 112 vertically up and down relative to the showerhead 104 within the cylindrical portion 107 of the showerhead 104. The dome 102 and the showerhead 104 are fixed relative to the pedestal 112. The gap between the bottom of the base 105 of the showerhead 104 and the top surface 116 of the pedestal 112 can be adjusted by vertically moving the pedestal 112 within the cylindrical portion 107 of the showerhead 104. For example, during substrate processing, the gap between the bottom of the base 105 of the showerhead 104 and the top surface 116 of the pedestal 112 can be about 0.2 inches, 0.15 inches, or 0.11 inches. When performing a cleaning process (hereinafter referred to as Figure 4 When the pedestal 112 is further lowered below the showerhead 104 to perform cleaning of the process chamber 103 as described in detail above, the pedestal 112 may be further lowered below the showerhead 104. During the cleaning process, the gap between the bottom of the base 105 of the showerhead 104 and the top surface 116 of the pedestal 112 may be much larger than during substrate processing.

[0065] The bottom end of the dome 102 is attached to the periphery of the top end of the sprinkler 104 using a cylindrical member 124. Specifically, the bottom end of the dome 102 is attached to the top surface 162 of the base 105 of the sprinkler 104 using the cylindrical member 124. For example, the cylindrical member 124 includes a ring having a shape of the letter "T" and includes a horizontal portion 126 and a vertical portion 128. The horizontal portion 126 has a first end defining an outer edge of the cylindrical member 124 and a second end defining an inner edge of the cylindrical member 124. The first end of the horizontal portion 126 (i.e., the outer edge of the cylindrical member 124) is attached to the periphery of the top surface 162 of the sprinkler 104 using a fastener (not shown). The outer wall of the dome 102 is attached to the vertical portion 128 along the inner diameter of the vertical portion 128. The inner wall of the dome 102 extends downward past the second end of the horizontal portion 126. The inner wall of the dome 102 is attached to the top surface 162 of the base 105 of the spray head 104 near the second end of the horizontal portion 126 (ie, near the inner edge of the cylindrical member 124).

[0066] The dome 102 generates a plasma (specifically, an inductively coupled plasma or ICP) in an upper portion of the processing chamber 103 as described below. The dome 102 receives one or more gases from a gas delivery system 130 via a gas injector 132 mounted on top of the dome 102. For example, as explained in detail below, the gas injector 132 can inject one or more process gases received from the gas delivery system 130 into the dome 102 during substrate processing. The gas injector 132 can inject one or more cleaning gases received from the gas delivery system 130 into the dome 102 during a cleaning process. The gas injector 132 comprises a ceramic material such as alumina.

[0067] The gas delivery system 130 includes one or more gas sources 150-1, 150-2, ..., and 150-N (collectively referred to as gas sources 150), where N is an integer greater than 1. The gas sources 150 are connected to a manifold 156 through valves 152-1, 152-2, ..., and 152-N (collectively referred to as valves 152) and mass flow controllers 154-1, 154-2, ..., and 154-N (collectively referred to as mass flow controllers 154). The manifold 156 is connected to the gas injectors 132. During substrate processing, the one or more gas sources 150 supply one or more process gases to the dome 102 via the manifold 156 and the gas injectors 132. As described below, during a cleaning process, the one or more gas sources 150 supply one or more cleaning gases to the dome 102 via the manifold 156 and the gas injectors 132.

[0068] The coil 134 is arranged around the dome 102. The coil 134 is described in detail below. In short, the coil 134 may include a plurality of turns (eg, 3 turns or more). A first end of the coil 134 is grounded. A second end of the coil 134 is connected to an RF generation system 136.

[0069] The RF generation system 136 generates RF power and outputs it to the coil 134. By way of example only, the RF generation system 136 may include an RF generator 138 that generates RF power. The RF power is fed to the coil 134 by a matching network 140. The RF power supplied to the coil 134 ignites one or more gases injected into the dome 102 by the gas injector 132 and generates a plasma 142 in the dome 102 (i.e., in the upper portion of the processing chamber 103). Thus, the processing chamber 103 does not use any remote plasma generated by a remote plasma source that is typically disposed outside the processing chamber 103. Instead, the plasma 142 is generated in situ (i.e., in the dome 102 of the processing chamber 103) during substrate processing and cleaning.

[0070] The base 105 of the showerhead 104 includes a first set of holes (also referred to as free-radical holes as described above) 160-1, 160-2, ... and 160-N (collectively referred to as free-radical holes 160), where N is an integer greater than 1. The free-radical holes 160 extend vertically from the top surface 162 of the base 105 of the showerhead 104 to the bottom surface 164 (also referred to as the faceplate 164) of the base 105 of the showerhead 104 facing the substrate. The free-radical holes 160 can be referred to as the first plenum of the showerhead 104.

[0071] The showerhead 104 filters ions from the plasma 142 and allows free radicals from the plasma 142 to enter the second portion of the processing chamber 103 through free radical holes 160. The free radicals react with the precursors in the gap between the showerhead 104 and the susceptor 112 and deposit a thin film on the substrate 114 using a process such as ALD. The open area provided by the free radical holes 160 for the free radicals to pass through the showerhead 104 and the density and pattern of the free radical holes 160 and the precursor holes 172 provide near zero radial and azimuthal non-uniformity in the film deposited using the showerhead 104.

[0072] In addition, the base 105 of the showerhead 104 includes a plenum 166 that is separate from (does not intersect) the free radical holes 160. The plenum 166 is not in fluid communication with the free radical holes 160. The plenum 166 may be referred to as a second plenum of the showerhead 104. The plenum 166 receives one or more precursor gases from the second gas delivery system 170 during substrate processing. During the cleaning process, the plenum 166 receives an inert gas from the second gas delivery system 170. Figure 3 The second gas delivery system 170 is described in detail.

[0073] The base 105 of the showerhead 104 also includes a second set of holes (also referred to as precursor holes) 172-1, 172-2, ... and 172-N (collectively referred to as precursor holes 172), where N is an integer greater than 1. The precursor holes 172 extend vertically from the plenum 166 through the base 105 of the showerhead 104 and through the faceplate 164 of the showerhead 104. During substrate processing, one or more precursor gases are supplied into the lower portion of the processing chamber through the precursor holes 172. The precursor holes 172 and the plenum 166 are not in fluid communication with the free radical holes 160.

[0074] The radical holes 160 and the precursor holes 172 are cylindrical. The diameter and length of the radical holes 160 are larger than the precursor holes 172. The radical holes 160 are tapered at their top end (i.e., on the side facing the dome 102). The total cross-sectional area of ​​the radical holes 160 is optimized to filter ions from the plasma 142 and only allow radicals from the plasma 142 to pass through the showerhead 104 and enter the lower part of the processing chamber 103 containing the pedestal 112. The adjustable gap between the faceplate 164 of the showerhead 104 and the top surface 116 of the pedestal 112 allows precise control of the micro volume in the ALD process. In addition, the narrow gap between the faceplate 164 of the showerhead 104 and the top surface 116 of the pedestal 112 prevents the depletion of radicals within the micro volume in the gap.

[0075] The outer wall 109-1 of the cylindrical portion 107 of the showerhead 104 does not directly contact the ceiling of the processing chamber 103. Due to this feature and because the cylindrical portion 107 of the showerhead 104 extends vertically below the top surface 116 of the pedestal 112 (on which the substrate 114 is arranged), the cylindrical portion 107 of the showerhead 104 provides a symmetrical thermal boundary condition (i.e., a constant temperature region) around the edge of the top surface 116 of the pedestal 112. Therefore, the pedestal 112 can be moved vertically within the cylindrical portion 107 (i.e., through the height of the cylindrical portion 107) to adjust the gap between the showerhead 104 and the pedestal 112 without significantly changing the thermal boundary conditions around the edge of the top surface 116 of the pedestal 112, which is advantageous during substrate processing.

[0076] In addition, the cylindrical portion 107 of the showerhead 104 also provides a constant constraint on the gas flow around the edge of the top surface 116 of the pedestal 112 when the pedestal 112 moves upward or downward within the cylindrical portion 107. Since the cylindrical portion 107 surrounds and is adjacent to the edge of the top surface 116 of the pedestal 112, the gas flow conditions around the edge of the top surface 116 of the pedestal 112 are kept constant, thus simplifying the process of controlling the trace gas in the gap between the showerhead 104 and the pedestal 112. Therefore, the pedestal 112 can be moved vertically within the cylindrical portion 107 (i.e., through the height of the cylindrical portion 107) to adjust the gap between the showerhead 104 and the pedestal 112 without significantly changing the gas flow conditions around the edge of the top surface 116 of the pedestal 112.

[0077] The base 105 of the nozzle 104 further includes a plurality of grooves 168-1, 168-2, ... and 168-N (collectively referred to as grooves 168), wherein N is an integer greater than 1. The grooves 168 form cooling channels through which the coolant flows (refer to Figure 3 A fluid delivery system 180 supplies coolant to the recess 168 through an inlet in the base 105 of the spray head 104 .

[0078] One or more temperature sensors (not shown) may be disposed in the base 105 of the showerhead 104. The temperature sensors may be connected to a temperature controller 182. The temperature controller 182 may control coolant from the fluid delivery system 180 to be supplied to the recess 168 to control the temperature of the showerhead 104 that receives heat from the pedestal 112 and the plasma 142. The coolant flows through the recess 168 and controls the temperature of the showerhead 104. During substrate processing and cleaning processes, the temperature of the showerhead 104 is lower than the temperature of the pedestal 112. During substrate processing and cleaning processes, the temperature controller 182 maintains the temperature of the showerhead 104 at a first default temperature (e.g., 50 degrees Celsius) that is lower than the temperature of the pedestal 112 (e.g., 550 degrees Celsius).

[0079] In addition, the pedestal 112 may include one or more heaters 184, a cooling system that receives a coolant from the fluid delivery system 180, and one or more temperature sensors. The temperature controller 182 may be connected to the temperature sensor in the pedestal 112. The temperature controller 182 may control the power supply to the heater 184. The temperature controller 182 may control the supply of coolant from the fluid delivery system 180 to the cooling system in the pedestal 112 to control the temperature of the pedestal 112. During substrate processing and cleaning processes, the temperature of the pedestal 112 is higher than the temperature of the showerhead 104. During substrate processing and cleaning processes, the temperature controller 182 maintains the temperature of the pedestal 112 at a second default temperature (e.g., 550 degrees Celsius) that is higher than the temperature of the showerhead 104 (e.g., 50 degrees Celsius).

[0080] The processing chamber 103 further includes a housing 125. The housing 125 is cylindrical. The housing 125 is mounted on the top of the showerhead 104. Specifically, the housing 125 is mounted on the vertical portion 128 of the cylindrical member 124. Figure 2 The housing 125 is described in detail below. Briefly, the housing 125 surrounds the dome 102 and the coil 134. The housing 125 includes a plurality of fans ( Figure 2 The fans are arranged in an azimuthally symmetrical configuration along the sidewalls of the housing 125 to provide uniform cooling of the dome 102 and the coil 134, as described below with reference to Figure 2 Described in detail.

[0081] Valve 186 and pump 188 control the pressure in process chamber 103. Pump 188 also exhausts reactants from process chamber 103 during substrate processing and cleaning processes. System controller 190 controls the components of substrate processing system 100 as described above and below. Part 2: Domes, coils, injectors and housings

[0082] Reference now Figure 1 and 2The dome 102, the coil 134, the gas injector (hereinafter referred to as the injector) 132 and the housing 125 are described in detail. As described above, the dome 102 is elliptical and includes a ceramic material such as alumina. The elliptical shape of the dome 102 is not just a design choice. Rather, the elliptical shape of the dome 102 was selected after extensive experiments because the elliptical shape significantly reduces the thermal stress on the dome 102 caused by the plasma compared to other shapes.

[0083] Additionally, the number of turns of coil 134 and the positioning of coil 134 around dome 102 are not merely design choices. Rather, the number of turns of coil 134 and the positioning of coil 134 around dome 102 are specifically designed to improve the heat load on dome 102 and increase the life of dome 102. Additionally, the elliptical shape of dome 102 and the number of turns and positioning of coil 134 around dome 102 are specifically designed to increase the volume of plasma 142, increase the surface area of ​​dome 102 that is bombarded by ions (which reduces damage to the interior walls of dome 102 compared to other shapes), and reduce thermal stress loads on dome 102.

[0084] Furthermore, as described above, the dome 102 and the injector 132 comprise a ceramic material such as alumina, which is also not a design choice. Other materials such as quartz can be etched away during substrate processing and cleaning processes due to the plasma 142 generated. Other materials such as quartz can be etched away during substrate processing and cleaning processes due to the corrosive cleaning gases (e.g., fluorine) and other harsh process chemicals used, as well as due to ion bombardment from the plasma. Therefore, after much experimentation, a ceramic material (e.g., alumina) that has a low dielectric constant and will not be etched away in these harsh environments was selected to replace quartz to construct the dome 102 and the injector 132. This is because the ceramic material such as alumina enables the use of the dome 102 and the injector 132 to generate the plasma 142 in the dome 102 using process gases during substrate processing and using cleaning gases during cleaning processes.

[0085] In addition, the inner wall of dome 102 is coated (e.g., sprayed) with a material (e.g., yttrium oxide) that is highly resistant to plasma-induced heat and corrosion. The coating on the inner wall of dome 102 is shown at 111. Coating 111 (e.g., yttrium oxide) not only bonds well with aluminum oxide, but also enhances the aluminum oxide's resistance to plasma-induced heat and corrosion. Thus, coating 111 further protects the inner wall of dome 102 from damage from ion bombardment from plasma 142 and damage from thermal and chemical stresses induced by the plasma.

[0086] Thus, using a dome 102 and injector 132 comprising a ceramic material such as alumina serves the dual purpose of enabling substrate processing and chamber cleaning using an in-situ plasma 142 generated with a wide range of harsh chemistries, and also providing longer life than components made from other materials such as quartz.

[0087] Figure 2 The housing 125 is schematically shown. The housing 125 includes fans (collectively referred to as fans 127) schematically shown as 127-1, 127-2, ..., 127-8. Although eight fans 127 are shown as examples only, any number of fans can be used. For symmetry, the number of fans 127 can be an even number. As described above, the fans 127 are arranged along the side walls of the housing 125 in an azimuthally symmetrical structure. Specifically, the housing 125 is cylindrical. The fans 127 are arranged on a circle equidistant from each other along the side walls of the housing 125. In addition, the fans 127 are located at the same distance d from the top and bottom of the housing 125.

[0088] Fans 127 provide cooling for dome 102 and coils 134. The cooling provided by the fans symmetrically arranged in housing 125 is also not merely a design choice. Rather, due to the azimuthally symmetrical arrangement selected after extensive experimentation, fans 127 evenly distribute heat throughout dome 102 and improve thermal uniformity throughout dome 102. Specifically, the azimuthally symmetrical arrangement of the fans along the sidewalls of housing 125 is designed for efficient heat dissipation during substrate processing where power loads are relatively low, and during cleaning processes where power loads are relatively high. Thus, in addition to the above-described elliptical shape of dome 102 and the design of coils 134, which reduce thermal stresses on dome 102 as described above, the azimuthally symmetrical arrangement of the fans in housing 125 further reduces thermal stresses on dome 102.

[0089] In some examples, although not shown, the fans 127 can be staggered. For example, the alternating fans 127 can be located on two different circles (e.g., the first circle and the second circle) along the side wall of the housing 125. The first circle can have the same distance (e.g., the first distance) from the top of the housing 125 as the second circle from the bottom of the housing 125. The distance between the two circles (e.g., the second distance) can be the same or different from the first distance. In each circle, the fans 127 can be equidistant from each other, but the positions of the fans 127 in the first circle can be staggered or offset relative to the positions of the fans 127 in the second circle. In other examples, the positions of the fans 127 in the two circles can be vertically aligned with each other. In some examples, the fans 127 can be arranged in more than two circles using any of the above configurations. Any combination of the above arrangements can be used. In addition, in some examples, in any of the above arrangements and combinations thereof, all fans 127 may have the same cooling capacity, and in other examples, at least some fans 127 may have cooling capacities different from other fans.

[0090] The design of the dome 102, coil 134, injector 132, and housing 125 with fan 127 provides many of the advantages described above. In addition, as described above, conventional substrate processing systems not only use a remote plasma source (which is eliminated in the substrate processing system 100 by using an in-situ plasma 142), but also require that the temperature of the showerhead and pedestal be changed during the cleaning process relative to the temperature used during substrate processing. Changing the temperature before and after the cleaning process wastes time and reduces the throughput of processed substrates.

[0091] In contrast, due to the use of an in-situ plasma 142 generated in the dome 102 during the substrate processing and cleaning processes (using different gases and chemistries), the temperature of the showerhead 104 and the pedestal 112 does not need to be changed between the substrate processing and cleaning processes. Rather, the temperature of the showerhead 104 and the pedestal 112 is maintained (i.e., the temperature is uniform or constant) during the substrate processing and cleaning processes. Uniformizing the temperature of the showerhead 104 and the pedestal 112 during the substrate processing and cleaning processes allows for seamless transitions between the substrate processing and cleaning processes. Uniform temperatures eliminate the time and production loss that is wasted due to the waiting period required in conventional substrate processing systems, in which the cleaning process must wait until a first temperature required for the cleaning process is reached before the cleaning process can begin, and then must wait until a second temperature required for the cleaning process is reached before the substrate processing can resume. Part 3: Reducing Sprinkler Head Contamination

[0092] In addition, as described above, during the cleaning process, particles ejected (e.g., etched) from the surface of the pedestal 112 (e.g., top surface 116) tend to contaminate the showerhead 104. In conventional cleaning processes, a remotely generated cleaning plasma is introduced into the processing chamber between the showerhead and the pedestal, which takes a long time to clean the showerhead for the reasons described above. In any case, some particles may still remain in the showerhead. Therefore, the showerhead needs to be requalified for use before processing the substrate.

[0093] In contrast, in substrate processing system 100, remote plasma is not used at all. Rather, cleaning gas is supplied into dome 102 via injector 132, and plasma 142 is generated in situ in dome 102. Thus, plasma 142 first cleans showerhead 104 and then cleans pedestal 112. Because plasma 142 encounters showerhead 104 first, plasma 142 can clean showerhead 104 more effectively than when a remote plasma is introduced between the showerhead and pedestal in a conventional cleaning process.

[0094] In addition, in order to reduce the contamination of the nozzle 104 by particles ejected (e.g., etched) from the surface (e.g., top surface 116) of the susceptor 112, the controller 190 controls the flow of the cleaning gas through the injector 132. For example, the cleaning gas can be supplied at a high flow rate and / or high pressure. The controlled flow of the cleaning gas through the injector 132 pushes the particles ejected (e.g., etched) from the surface of the susceptor 112 downward relative to the nozzle 104. Therefore, the contamination of the nozzle 104 by particles ejected (e.g., etched) from the surface of the susceptor 112 is reduced (suppressed) by the controlled flow of the cleaning gas of the injector 132.

[0095] In addition, because the injector 132 comprises a ceramic material such as alumina, the injector 132 is able to handle the additional corrosion stress imposed on the injector 132 by the high flow rate of the cleaning gas (i.e., it will not be damaged). Unifying the temperature of the showerhead 104 and the pedestal 112 during the substrate processing and cleaning processes requires that the pedestal 112 be maintained at the same high temperature during the cleaning process as during the substrate processing. The high temperature of the pedestal 112 may cause more particles to be ejected (e.g., etched) from the surface of the pedestal 112, which may contaminate the showerhead 104 without a high flow rate of the cleaning gas through the injector 132. Controlling the flow rate of the cleaning gas through the injector 132 suppresses contamination of the showerhead 104 by particles ejected (e.g., etched) from the surface of the pedestal 112 as described above.

[0096] Thus, the ability of the injector 132 constructed using a ceramic material such as alumina to handle the additional corrosive stress imposed by the high flow rate of the cleaning gas allows the temperature of the susceptor 112 to be maintained at the same high temperature used during substrate processing without contaminating the showerhead 104. Although the high temperature of the susceptor 112 may cause more particles to be ejected (e.g., etched) from the surface of the susceptor 112, the high flow rate of the cleaning gas through the injector 132 may inhibit the showerhead 104 from being contaminated by particles ejected (e.g., etched) from the surface of the susceptor 112. Thus, controlling the flow of the cleaning gas through the injector 132 allows for uniform temperatures during substrate processing and cleaning processes.

[0097] While controlling the flow of the cleaning gas through the injector 132 will mitigate the particle contamination problem, the showerhead 104 may remain contaminated due to any residual traces of the cleaning gas that may be captured and trapped in the plenum 166 and holes 160, 172 of the showerhead 104. The second gas delivery system 170 helps further mitigate the particle contamination problem, as described below with reference to Figure 3 As described below, the second gas delivery system 170 can also mitigate contamination of the showerhead 104 due to stagnant cleaning gas trapped in the plenum 166 and holes 172 of the showerhead 104.

[0098] Figure 3 The second gas delivery system 170 is shown in more detail. Although shown separately, the second gas delivery system 170 can be a part of the second gas delivery system 130. The second gas delivery system 170 can be similar to the second gas delivery system 130. As shown, the substrate processing system 100 further includes valves 174, 176 and a manifold 178 connected to the second gas delivery system 170 and the plenum 166 of the showerhead 104. The second gas delivery system 170 is connected to the plenum 166 of the showerhead 104 through the valves 174, 176 and the manifold 178. As shown, the valves 174, 176 are connected to the second gas delivery system 170 and the manifold 178.

[0099] The valve 174 is connected to one or more gas sources supplying one or more precursor gases in the second gas delivery system 170. Although a single valve 174 is shown here, there may be multiple valves connected to multiple gas sources supplying multiple precursor gases in the second gas delivery system 170, respectively. The multiple valves may be controlled in the same manner as the valve 174 described below. The valve 176 is connected to a gas source supplying an inert gas in the second gas delivery system 170. The controller 190 controls the valves 174, 176 as described below.

[0100] During substrate processing, the controller 190 opens the valve 174 and closes the valve 176. Thus, the second gas delivery system 170 supplies one or more precursor gases to the plenum 166 of the showerhead 104 via the valve 174 and the manifold 178 during substrate processing.

[0101] During the cleaning process, the controller 190 closes the valve 174 and opens the valve 176. The second gas delivery system 170 supplies the inert gas to the plenum 166 of the showerhead 104 via the valve 176 and the manifold 178 during the cleaning process. The inert gas is supplied in a thin stream at a low velocity. The inert gas flows through the showerhead 104 at a low velocity for two purposes.

[0102] First, the flow of the inert gas inhibits backflow (i.e., flow of any material including particles ejected (e.g., etched) from the surface of the pedestal 112) into the showerhead 104 and dome 102. Essentially, the flow of the inert gas inhibits any material from flowing back from the lower portion of the processing chamber 103 to the upper portion of the processing chamber 103. Second, the flow of the inert gas removes any stagnant cleaning gas that might otherwise reside in the plenum 166 and holes 160, 172 of the showerhead 104.

[0103] Thus, during the cleaning process, the controlled flow of cleaning gas through the injector 132 and the low rate of inert gas flow through the showerhead 104 significantly reduces and / or eliminates contamination of the showerhead 104 by particles ejected (e.g., etched) from the surface of the pedestal 112 and any stagnant cleaning gas that may otherwise remain in the plenum 166 and holes 160, 172 of the showerhead 104.

[0104] Thus, the elliptical shape of the dome 102, the ceramic material, and the coating 111 reduce the heat load on the dome 102 and the etching of the inner wall of the dome 102. The design of the coil 134 further reduces the heat load on the dome 102 and increases the plasma volume in the dome 102. The injector 132 containing the ceramic material maintains a high flow of corrosive cleaning gas, thereby inhibiting particle contamination of the showerhead 104. The inert gas flow through the showerhead 104 further reduces the contamination of the showerhead 104 by preventing the cleaning gas from stagnating in the showerhead. The controlled flow of the cleaning gas through the injector 132 and the flow of the inert gas through the showerhead 104 eliminates the contamination of the showerhead 104 caused by particles ejected (e.g., etched) from the surface of the susceptor 112 and any stagnant cleaning gas that may have otherwise settled in the showerhead 104. The housing 125 with the fan 127 improves the thermal uniformity on the dome 102.

[0105] The above features enable the generation of an in-situ cleaning plasma while unifying the temperatures of the showerhead 104 and the pedestal 112 and reducing the heat load on the dome 102 during substrate processing and chamber cleaning. Therefore, the use of an in-situ cleaning plasma and unifying the temperatures of the showerhead 104 and the pedestal 112 and reducing the heat load on the dome 102 during substrate processing and cleaning processes increases the life of the dome 102. The use of an in-situ cleaning plasma and unifying the temperatures of the showerhead 104 and the pedestal 112 improves the cleaning process. Unifying the temperatures of the showerhead 104 and the pedestal 112 eliminates the delay that would otherwise be necessary for temperature transitions between substrate processing and cleaning processes, thereby increasing tool productivity. Section 4: Substrate Handling and Chamber Cleaning Methods

[0106] Figure 4 A method 200 for processing a substrate and cleaning a process chamber 103 according to the present disclosure is shown. The method 200 is also a method of operating the substrate processing system 100. For example, the controller 190 executes the method 200 and controls elements of the substrate processing system 100 according to the method 200.

[0107] At 202, the method 200 determines whether it is time to process the substrate. For example, the method 200 determines whether the substrate 114 has been loaded into the processing chamber 103, and whether the gap between the substrate 114 and the showerhead 104 is adjusted as required by the process (e.g., ALD) used to process the substrate 114. If it is time to process the substrate, then at 204, the method 200 heats the pedestal 112 and the showerhead 104 to the temperature required for the process (e.g., ALD) to be performed on the substrate 114. In some processes, the pedestal 112 and the showerhead 104 may be preheated to the temperature required for the process. At 206, the method 200 supplies one or more process gases to the injector 132, and optionally, according to the process requirements, one or more precursors to the showerhead 104. At 208, the method 200 supplies RF power to the coil 134 to excite the plasma 142 (if used) in the dome 102.

[0108] At 210, the method determines whether it is time to clean the process chamber 103 (e.g., time to perform periodic preventive maintenance on the process chamber 103). If it is not necessary to clean the process chamber 103, then at 212, the method 200 continues to process the substrate (e.g., the same or a new substrate), and the method 200 returns to 206. If it is necessary to clean the process chamber 103, then at 214, the method 200 maintains the temperature of the pedestal 112 and the showerhead 104 at the same temperature as used at 204 to process the substrate in 206 and 208. The method 200 does not change the temperature of the pedestal 112 and the showerhead 104. The method 200 removes the substrate 114 from the process chamber 103 and lowers the pedestal 112 relative to the showerhead 104.

[0109] At 216, the method 200 stops the flow of process gases and precursor gases into the injector 132 and the showerhead 104, and stops the RF supply (if used at 208). At 218, the method 200 supplies one or more cleaning gases (e.g., a cleaning gas or a mixture of a cleaning gas and other cleaning chemistries) to the injector 132 and supplies an inert gas from the second gas delivery system 120 directly to the showerhead 104. At 220, the method 200 supplies RF power to the coil 134 to energize an in-situ cleaning plasma in the dome 102. As described above, the method 200 also controls the flow of one or more cleaning gases through the injector 132 and the flow of the inert gas through the showerhead 104.

[0110] At 222, the method determines whether the time to stop the cleaning process has arrived (i.e., whether the chamber cleaning is complete). If the time to stop the cleaning process has not arrived (i.e., if the chamber cleaning has not yet completed), the method 200 returns to 218 and continues the cleaning process at 218 and 220. If the time to stop the cleaning process has arrived, at 224, the method 200 stops the flow of one or more cleaning gases into the injector 132, stops the flow of inert gas into the showerhead 104, and stops supplying RF power to the coil 134. At 226, the method 200 maintains the temperature of the pedestal 112 and the showerhead 104 at the temperature used during the cleaning process in 218 and 220, which is the same temperature used to process the substrate in 206 and 208. The method 200 does not change the temperature of the pedestal 112 and the showerhead 104. Thereafter, at 212, the method 200 continues processing the substrate (e.g., a new substrate) without delay because the pedestal 112 and the showerhead 104 are already at the temperature used to process the substrate in 206 and 208.

[0111] The above predetermined ranges are now explained in more detail. For example, a process (e.g., ALD) may require the temperatures of the showerhead 104 and the pedestal 112 to be 50 degrees Celsius and 550 degrees Celsius, respectively, to process a substrate. These temperatures of the showerhead 104 and the pedestal 112 when the process is processing a substrate may be referred to as the predetermined temperatures of the showerhead 104 and the pedestal 112 for the process.

[0112] As mentioned above Figure 1 As described above, the temperature controller 182 strictly controls the temperature of these components. However, in some cases, at the beginning of the cleaning process, these temperatures may be slightly different and may not be exactly the same as the temperatures used during substrate processing. However, the variation is small and is strictly controlled within a predetermined range, which can be as narrow as ±0-1% of the predetermined temperature.

[0113] For example, assume that a process (e.g., ALD) requires the temperatures of the showerhead 104 and the pedestal 112 to be 50 degrees Celsius and 550 degrees Celsius, respectively, to process a substrate. At the beginning of the cleaning process, the temperature of the showerhead 104 may be within 0-1% of 50 degrees Celsius, and the temperature of the pedestal 112 may be within 0-1% of 550 degrees Celsius. The temperature controller 182 may sense these changes using temperature sensors in the showerhead 104 and the pedestal 112. Based on the sensed changes, the temperature controller 182 may control one or more of the heater 184 in the pedestal 112 and the coolant supplied to the pedestal 112 to quickly return these temperatures to their respective predetermined temperatures. A similar procedure may be used after the cleaning process is completed and at the beginning of processing a new substrate using the process (e.g., ALD).

[0114] Thus, during substrate processing and cleaning processes, the temperature of these components is substantially maintained at a temperature close to or substantially equal to the temperature required for a given process and within a narrow predetermined range (e.g., ±0-1%). Thus, after a cleaning process, substrate processing can be quickly resumed without the long delays that are typically required to allow the temperature of the components to transition from a first set of temperatures used for the cleaning process to a second set of distinct temperatures typically used for processing substrate processes. Additionally, during substrate processing and cleaning processes, the temperature controller 182 can maintain the temperatures of the showerhead 104 and the pedestal 112 the same without variation (i.e., unchanged). Thus, after a cleaning process, substrate processing can be immediately resumed without any delays that are typically required to allow the temperature of the components to transition from a first set of temperatures used for the cleaning process to a second set of distinct temperatures typically used for processing substrate processes.

[0115] The foregoing description is merely illustrative in nature and is in no way intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because other modifications will become apparent upon studying the drawings, description and appended claims.

[0116] It should be understood that one or more steps in the method may be performed in different orders (or simultaneously) without changing the principles of the present disclosure. In addition, although each embodiment is described above as having certain features, any one or more of those features described with respect to any embodiment of the present disclosure may be implemented in the features of any other embodiment and / or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and the permutation of one or more embodiments with respect to each other remains within the scope of the present disclosure.

[0117] Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "next to," "on top of," "above," "below," and "disposed." Unless the relationship between a first and a second element is explicitly described as "direct," when such a relationship is described in the above disclosure, the relationship can be a direct relationship, in which there are no other intervening elements between the first and second elements, but can also be an indirect relationship, in which there are one or more intervening elements (spatially or functionally) between the first and second elements. As used herein, the phrase "at least one of A, B, and C" should be interpreted to mean a logical (A or B or C), using a non-exclusive logical OR, and should not be interpreted to mean "at least one of A, at least one of B, and at least one of C."

[0118] In some implementations, the controller is part of a system, which may be part of the above examples. Such a system may include a semiconductor processing device, which includes one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling their operation before, during, and after processing of semiconductor wafers or substrates. The electronics may be referred to as a "controller," which may control various components or subcomponents of one or more systems.

[0119] Depending on the processing requirements and / or system type, the controller can be programmed to control any of the processes disclosed herein, including the delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer into and out of tools and other transfer tools and / or load locks connected or docked with a particular system.

[0120] Broadly speaking, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receives instructions, issues instructions, controls operations, enables cleaning operations, enables endpoint measurements, etc. Integrated circuits may include chips in the form of firmware that stores program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software).

[0121] Program instructions may be instructions sent to a controller in the form of various individual settings (or program files) that define operating parameters for performing a particular process on or for a semiconductor wafer or system. In some embodiments, the operating parameters may be part of a recipe defined by a process engineer to accomplish one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0122] In some implementations, the controller can be part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller can be in the "cloud" or all or part of a wafer fab host system that can allow remote access to wafer processing. The computer can enable remote access to the system to monitor the current progress of a manufacturing operation, examine the history of past manufacturing operations, examine trends or performance criteria for multiple manufacturing operations, change parameters of a current process, set processing steps to follow a current process, or start a new process.

[0123] In some examples, a remote computer (e.g., a server) may provide process recipes to the system over a network (which may include a local network or the Internet). The remote computer may include a user interface that enables input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control.

[0124] Thus, as described above, the controller may be distributed, for example, by including one or more discrete controllers networked together and working toward a common purpose, such as the processes and controls described herein. An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber that communicate with one or more integrated circuits remotely (e.g., at a platform level or as part of a remote computer), which combine to control the process on the chamber.

[0125] Example systems may include, but are not limited to, plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfer edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the manufacture and / or preparation of semiconductor wafers.

[0126] As described above, depending on one or more processing steps to be performed by the tool, the controller can communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a host computer, another controller, or tools used in material transport to transport wafer containers to and from tool locations and / or load ports in a semiconductor manufacturing facility.

Claims

1. A substrate processing system, comprising: a processing chamber comprising a first portion and a second portion, the first portion comprising a dome, the dome comprising a ceramic material and being oval in shape; a susceptor configured to process a substrate disposed in the second portion of the processing chamber; a showerhead disposed at a base of the dome between the first portion and the second portion of the process chamber; an injector including the ceramic material, mounted on the dome and configured to inject process gas and cleaning gas during substrate processing and during cleaning of the chamber, respectively; a coil disposed around a portion of the dome; a radio frequency (RF) generator configured to supply RF power to the coil to generate a plasma within the dome during processing of the substrate and during the cleaning of the processing chamber; as well as A controller is configured to control the temperature of the pedestal and the showerhead to respective predetermined temperatures within a predetermined range during processing of the substrate and during the cleaning of the process chamber. 2 . The substrate processing system of claim 1 , wherein the predetermined range is ±0-1% of the corresponding predetermined temperature.

3. The substrate processing system of claim 1, wherein the controller is configured to maintain the temperatures of the pedestal and the showerhead at the respective predetermined temperatures during processing of the substrate and during cleaning of the process chamber.

4. The substrate processing system of claim 1, wherein the ceramic material is alumina.

5. The substrate processing system of claim 1, wherein an inner wall of the dome is coated with a second material that is heat-resistant and corrosion-resistant. The substrate processing system of claim 5 , wherein the second material is yttrium oxide.

7. The substrate processing system of claim 1, further comprising a housing disposed around the dome and the coil, the housing being attached to a periphery of the showerhead, the housing comprising a plurality of fans disposed in an azimuthally symmetrical manner along a side wall of the housing.

8. The substrate processing system of claim 1 , further comprising a gas delivery system configured to supply the cleaning gas through the injector at a flow rate that inhibits particles ejected from the pedestal from contaminating the showerhead during the cleaning of the processing chamber.

9. The substrate processing system of claim 1, further comprising a gas delivery system configured to supply an inert gas directly to the showerhead to inhibit particles ejected from the pedestal from contaminating the showerhead during the cleaning of the processing chamber.

10. The substrate processing system of claim 1, further comprising a gas delivery system configured to supply an inert gas directly to the showerhead to prevent the cleaning gas from stagnating in the showerhead after the cleaning of the process chamber.

11. The substrate processing system of claim 1 , further comprising a gas delivery system, wherein the showerhead comprises: a first plenum configured to filter ions from the plasma and to deliver radicals from the plasma to the second portion of the processing chamber; and A second plenum is configured to (i) directly receive a precursor from the gas delivery system and supply the precursor to the second portion of the processing chamber during the substrate processing, and (ii) directly receive an inert gas from the gas delivery system during the cleaning of the processing chamber.

12. The substrate processing system of claim 1, wherein the coil comprises a plurality of turns, and wherein the plurality of turns and positions of the turns around the dome distribute ions and heat loads from the plasma throughout the dome.

13. The substrate processing system of claim 1, wherein the pedestal comprises a heater, the substrate processing system further comprising: a fluid delivery system configured to supply coolant to the base and the spray head; The controller is configured to control the heater and the flow of the coolant to maintain the temperatures of the showerhead and the pedestal within the predetermined range of the respective predetermined temperatures during processing of the substrate and during cleaning of the process chamber.

14. The substrate processing system of claim 1, wherein the pedestal comprises a heater, the substrate processing system further comprising: a fluid delivery system configured to supply coolant to the base and the spray head; The controller is configured to control the heater and the flow of the coolant to maintain the temperatures of the pedestal and the showerhead at the respective predetermined temperatures during processing of the substrate and during cleaning of the process chamber.

15. A method for cleaning a processing chamber, the processing chamber comprising a susceptor and a showerhead and configured to process a substrate, the method comprising: controlling the temperature of the susceptor and the showerhead during the cleaning of the processing chamber to be within a predetermined range of respective predetermined temperatures used during processing of the substrate; supplying a cleaning gas to an elliptical dome of the process chamber through an injector, the injector being mounted on the elliptical dome, the elliptical dome and the injector comprising a ceramic material; generating a plasma in the elliptical dome by supplying radio frequency (RF) power to a coil disposed around the elliptical dome; as well as The flow of the cleaning gas through the injector is controlled to inhibit contamination of the showerhead by particles ejected from the susceptor.

16. The method of claim 15, wherein the predetermined range is ±0-1% of the corresponding predetermined temperature.

17. The method of claim 15, further comprising maintaining the temperatures of the pedestal and the showerhead at the respective predetermined temperatures during the processing of the substrate and during the cleaning of the processing chamber.

18. The method of claim 15, further comprising spraying an inner wall of the elliptical dome with a second material that is heat and corrosion resistant.

19. The method of claim 18, wherein the ceramic material is aluminum oxide and the second material is yttrium oxide.

20. The method of claim 15, further comprising: enclosing the elliptical dome and the coil in a housing attached to the periphery of the showerhead; and The elliptical dome is cooled using a plurality of fans arranged in an azimuthally symmetrical manner along the side walls of the housing.

21. The method of claim 15, further comprising supplying an inert gas directly to the showerhead to further suppress the contamination of the showerhead by the particles.

22. The method of claim 15, further comprising flowing an inert gas through the showerhead to prevent the cleaning gas from stagnating in the showerhead.

23. The method of claim 15, further comprising arranging turns of the coil around the elliptical dome to distribute ions and heat loads from the plasma throughout the elliptical dome.

24. The method of claim 15, further comprising, after the cleaning of the process chamber: stopping supplying the cleaning gas and the RF power; controlling the temperatures of the base and the showerhead to be within the predetermined range of the corresponding predetermined temperatures; and A process gas is supplied to the elliptical dome through the injector to process a second substrate in the processing chamber.

25. The method of claim 24, further comprising supplying a precursor directly to the showerhead.

26. The method of claim 24, further comprising: exciting a second plasma in the elliptical dome by supplying the RF power to the coil; and Ions from the second plasma are filtered and radicals from the second plasma are transported to the second substrate.

27. The method of claim 24, further comprising supplying a coolant through the pedestal and the showerhead to maintain the temperatures of the showerhead and the pedestal within the predetermined range of the respective predetermined temperatures during the processing of the second substrate in the processing chamber.

28. The method of claim 24, further comprising supplying a coolant through the pedestal and the showerhead to maintain the temperatures of the pedestal and the showerhead at the respective predetermined temperatures during the processing of the second substrate in the processing chamber.

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