Processing method, processing device, method for producing semiconductor device, and program

Abstract

Provided is a technique that makes it possible to improve the surface roughness of a film.　The present invention includes (a) a step in which a second film is formed on a first film, the etching rate of the second film when a first gas capable of removing at least part of the first film is supplied being a second etching rate equal to or lower than a first etching rate of the first film, and (b) a step in which the first gas is supplied to the first film.

Description

Processing method, processing apparatus, semiconductor device manufacturing method and program

[0001] The present disclosure relates to a processing method, a processing apparatus, a method for manufacturing a semiconductor device, and a program.

[0002] As one step in the manufacturing process of a semiconductor device, a process may be performed in which a crystal layer dividing film is formed on the surface of a metal-containing film or abnormal growth nuclei are removed from the surface of the metal-containing film to form multiple layers of the metal-containing film on a substrate (see, for example, Patent Document 1).

[0003] International Publication No. 2021 / 053761

[0004] The present disclosure provides a technique that can improve the roughness of a film surface (hereinafter referred to as surface roughness).

[0005] According to one aspect of the present disclosure, there is provided a technique comprising: (a) forming a second film on a first film, the second film having an etching rate, when supplied with a first gas capable of removing at least a portion of the first film, of a second etching rate that is equal to or lower than the first etching rate of the first film; and (b) supplying the first gas to the first film.

[0006] According to the present disclosure, it is possible to improve the surface roughness of the film.

[0007] FIG. 1 is a longitudinal cross-sectional view showing an outline of a vertical processing furnace of a substrate processing apparatus according to one embodiment of the present disclosure. FIG. 2 is a schematic transverse cross-sectional view taken along line A-A in FIG. 1. FIG. 3 is a schematic configuration diagram of a controller of a substrate processing apparatus according to one embodiment of the present disclosure, and is a block diagram showing a control system of the controller. FIG. 4 is a diagram showing a process flow according to one embodiment of the present disclosure. FIG. 5 is a flow diagram showing a first cleaning process in the process flow of FIG. 4. FIG. 6(A) is a diagram for explaining the state of the surface inside the reaction tube before the cleaning process. FIG. 6(B) is a diagram for explaining the state of the surface inside the reaction tube when the cleaning process is performed from the state shown in FIG. 6(A). FIG. 7(A) is a diagram for explaining the state of the surface inside the reaction tube before the cleaning process. FIG. 7(B) is a diagram for explaining the state of the surface inside the reaction tube when the treatment process is performed from the state shown in FIG. 7(A). FIG. 7(C) is a diagram for explaining the state of the surface inside the reaction tube when the cleaning process is performed from the state shown in FIG. 7(B). FIG. 8 is a flow diagram showing a first cleaning process according to a second embodiment of the present disclosure. FIG. 9 is a flow chart showing the first cleaning process in the third aspect of the present disclosure.

[0008] <One Aspect of the Present Disclosure> One aspect of the present disclosure will be described below, mainly with reference to Figures 1 to 7. Note that all drawings used in the following description are schematic, and the dimensional relationships between elements, the ratios of elements, and the like shown in the drawings do not necessarily match those in reality. Furthermore, the dimensional relationships between elements, the ratios of elements, and the like do not necessarily match between multiple drawings.

[0009] (1) Configuration of the Substrate Processing Apparatus As shown in Fig. 1, the processing furnace 202 has a heater 207 as a temperature adjustment unit (heating unit). The heater 207 is cylindrical and is installed vertically by being supported by a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) gas by heat.

[0010] A reaction tube 203 is disposed inside the heater 207 concentrically with the heater 207. The reaction tube 203 is made of, for example, quartz (SiO ２The reaction tube 203 is made of a heat-resistant material such as silicon carbide (SiC) or silicon carbide (SiC) and has a cylindrical shape with a closed top and an open bottom. A manifold 209 is disposed concentrically below the reaction tube 203. The manifold 209 is made of a metal material such as stainless steel (SUS) and has a cylindrical shape with open top and bottom ends. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 to support the reaction tube 203. An O-ring 220a serving as a sealing member is provided between the manifold 209 and the reaction tube 203. The reaction tube 203 is installed vertically, similar to the heater 207. The reaction tube 203 and the manifold 209 mainly constitute a processing vessel (reaction vessel). A processing chamber 201 is formed in the cylindrical hollow portion of the processing vessel. The processing chamber 201 is configured to accommodate wafers 200 as substrates.

[0011] Nozzles 249a to 249c serving as first to third supply units are provided in the processing chamber 201 so as to penetrate the sidewall of the manifold 209. The nozzles 249a to 249c are also referred to as first to third nozzles, respectively. The nozzles 249a to 249c are made of, for example, SiO ２ Alternatively, the nozzles 249a to 249c are made of a heat-resistant material such as SiC, etc. Gas supply pipes 232a to 232c are connected to the nozzles 249a to 249c, respectively.

[0012] Gas supply pipes 232a to 232c are respectively provided with mass flow controllers (MFCs) 241a to 241c, which are flow rate control devices (flow rate control parts), and valves 243a to 243c, which are on-off valves, in order from the upstream side of the gas flow. Gas supply pipes 232d and 232f are respectively connected to gas supply pipe 232a downstream of valve 243a. Gas supply pipe 232e is connected to gas supply pipe 232b downstream of valve 243b. Gas supply pipe 232g is connected to gas supply pipe 232c downstream of valve 243c. Gas supply pipes 232d to 232g are respectively provided with MFCs 241d to 241g and valves 243d to 243g in order from the upstream side of the gas flow.

[0013] 2, the nozzles 249a to 249c are respectively provided in a circular space between the inner wall of the reaction tube 203 and the wafers 200 in a plan view, extending from the bottom to the top of the inner wall of the reaction tube 203 and rising upward in the arrangement direction of the wafers 200. That is, the nozzles 249a to 249c are respectively provided in regions horizontally surrounding the wafer arrangement region on the sides of the wafer arrangement region in which the wafers 200 are arranged, and extending along the wafer arrangement region. In a plan view, the nozzle 249b is disposed so as to face a later-described exhaust port 233 in a straight line across the center of the wafer 200 being loaded into the processing chamber 201. The nozzles 249a and 249c are disposed so as to sandwich a line L passing through the nozzle 249b and the center of the exhaust port 233 along the inner wall of the reaction tube 203 (the outer periphery of the wafers 200) from both sides. Gas supply holes 250a to 250c for supplying gas are provided on the side surfaces of the nozzles 249a to 249c, respectively. Each of the gas supply holes 250a to 250c opens to face (face) the exhaust port 233 in a plan view, and is capable of supplying gas toward the wafers 200. A plurality of gas supply holes 250a to 250c are provided from the bottom to the top of the reaction tube 203.

[0014] A first process gas is supplied from the gas supply pipe 232a into the process chamber 201 via the MFC 241a, the valve 243a, and the nozzle 249a. The first process gas may be, for example, a source gas. Examples of the source gas include a metal-containing gas, which is a gas containing a metal element, and a silicon (Si)-containing gas.

[0015] A second process gas is supplied from the gas supply pipe 232b into the process chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b. The second process gas may be, for example, a reactive gas. The reactive gas may be, for example, a nitriding gas.

[0016] A third process gas is supplied from the gas supply pipe 232c into the process chamber 201 via the MFC 241c, the valve 243c, and the nozzle 249c. The third process gas may be, for example, a reducing gas or a treatment gas (also referred to as a modifying gas) serving as the second gas. The third process gas may be, for example, a gas containing Si and hydrogen (H).

[0017] A cleaning gas as a first gas is supplied from the gas supply pipe 232d through the MFC 241d, the valve 243d, the gas supply pipe 232a, and the nozzle 249a into the processing chamber 201. As the cleaning gas, for example, a halogen-containing gas such as a halogen-based gas can be used.

[0018] Inert gas is supplied from the gas supply pipes 232e to 232g through the MFCs 241e to 241g, the valves 243e to 243g, the gas supply pipes 232e to 232g, and the nozzles 249a to 249c into the processing chamber 201. The inert gas acts as a purge gas, a carrier gas, a dilution gas, etc.

[0019] The first process gas supply system (also referred to as a source gas supply system) mainly includes the gas supply pipe 232a, the MFC 241a, and the valve 243a. The second process gas supply system (also referred to as a reactive gas supply system) mainly includes the gas supply pipe 232b, the MFC 241b, and the valve 243b. The third process gas supply system (also referred to as a reducing gas supply system, a second gas supply system, a treatment gas supply system, or a modifying gas supply system) mainly includes the gas supply pipe 232c, the MFC 241c, and the valve 243c. The cleaning gas supply system (also referred to as a first gas supply system) mainly includes the gas supply pipe 232d, the MFC 241d, and the valve 243d. The inert gas supply system mainly includes the gas supply pipes 232e to 232g, the MFCs 241e to 241g, and the valves 243e to 243g.

[0020] Any or all of the various supply systems described above may be configured as an integrated supply system 248 in which valves 243a to 243g, MFCs 241a to 241g, etc. are integrated. The integrated supply system 248 is connected to each of the gas supply pipes 232a to 232g, and is configured so that the supply operation of various substances (various gases) into the gas supply pipes 232a to 232g, i.e., the opening and closing operation of the valves 243a to 243g and the flow rate adjustment operation by the MFCs 241a to 241g, etc., are controlled by a controller 121, which will be described later. The integrated supply system 248 is configured as an integrated or separate integrated unit, and can be attached and detached to and from the gas supply pipes 232a to 232g, etc., so that maintenance, replacement, expansion, etc. of the integrated supply system 248 can be performed on an integrated unit basis.

[0021] An exhaust port 233 for exhausting the atmosphere inside the process chamber 201 is provided at the bottom of the sidewall of the reaction tube 203. As shown in FIG. 2, the exhaust port 233 is provided at a position facing the nozzles 249a to 249c (gas supply holes 250a to 250c) across the wafer 200 in a plan view. The exhaust port 233 may be provided along the sidewall of the reaction tube 203 from the bottom to the top, i.e., along the wafer arrangement area. An exhaust pipe 231 is connected to the exhaust port 233. A vacuum pump 246 serving as a vacuum exhaust device is connected to the exhaust pipe 231 via a pressure sensor 245 serving as a pressure detector (pressure detection unit) for detecting the pressure inside the process chamber 201 and an APC (Auto Pressure Controller) valve 244 serving as a pressure regulator (pressure adjustment unit). The APC valve 244 is configured to be able to evacuate and stop the evacuation of the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operating, and further, to be able to adjust the pressure inside the processing chamber 201 by adjusting the valve opening based on pressure information detected by the pressure sensor 245 while the vacuum pump 246 is operating. An exhaust system is mainly configured by the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may be included in the exhaust system.

[0022] A seal cap 219 serving as a furnace port cover capable of airtightly closing the lower end opening of the manifold 209 is provided below the manifold 209. The seal cap 219 is made of a metal material such as SUS and is formed in a disk shape. An O-ring 220b serving as a sealing member that abuts against the lower end of the manifold 209 is provided on the upper surface of the seal cap 219. A rotation mechanism 267 for rotating the boat 217 (described later) is provided below the seal cap 219. A rotation shaft 255 of the rotation mechanism 267 passes through the seal cap 219 and is connected to the boat 217. The rotation mechanism 267 is configured to rotate the boat 217, thereby rotating the wafers 200. The seal cap 219 is configured to be vertically raised and lowered by a boat elevator 115 serving as an elevating mechanism installed outside the reaction tube 203. The boat elevator 115 is configured as a transfer device (transfer mechanism) that transfers the wafers 200 into and out of the processing chamber 201 by raising and lowering the seal cap 219 .

[0023] A shutter 219s is provided below the manifold 209 as a furnace port cover that can airtightly close the lower end opening of the manifold 209 when the seal cap 219 is lowered and the boat 217 is unloaded from the process chamber 201. The shutter 219s is made of a metal material such as SUS and has a disk shape. An O-ring 220c is provided on the upper surface of the shutter 219s as a sealing member that abuts against the lower end of the manifold 209. The opening and closing operation (lifting and lowering operation, rotating operation, etc.) of the shutter 219s is controlled by a shutter opening and closing mechanism 115s.

[0024] The boat 217 as a substrate support is configured to support a plurality of wafers 200, for example, 25 to 200 wafers 200, in a horizontal position and aligned vertically with their centers aligned, i.e., arranged at intervals. ２ The boat 217 is made of a heat-resistant material such as silicon carbide (SiC). ２ Heat insulating plates 218 made of heat resistant material such as silicon carbide (SiC) are supported in multiple stages.

[0025] A temperature sensor 263 serving as a temperature detector is installed inside the reaction tube 203. By adjusting the power supply to the heater 207 based on temperature information detected by the temperature sensor 263, the temperature distribution inside the processing chamber 201 becomes a desired one. The temperature sensor 263 is installed along the inner wall of the reaction tube 203.

[0026] As shown in Fig. 3, the controller 121, which is a control unit (control means), is configured as a computer including a CPU (Central Processing Unit) 121a, a RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, the storage device 121c, and the I / O port 121d are configured to be able to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122 configured as, for example, a touch panel is connected to the controller 121. An external storage device 123 can also be connected to the controller 121.

[0027] The storage device 121c is composed of, for example, a flash memory, a hard disk drive (HDD), a solid state drive (SSD), etc. Control programs for controlling the operation of the substrate processing apparatus, process recipes describing procedures and conditions for substrate processing (described later), etc., are readably recorded and stored in the storage device 121c. The process recipe is a combination of procedures for substrate processing (described later) that are executed by the controller 121 in the substrate processing apparatus to obtain a predetermined result, and functions as a program. Hereinafter, the process recipes, control programs, etc. are collectively referred to simply as programs. The process recipes are also simply referred to as recipes. In this specification, the term "program" may refer to a recipe alone, a control program alone, or both. The RAM 121b is configured as a memory area (work area) for temporarily storing programs, data, etc. read by the CPU 121a.

[0028] The I / O port 121d is connected to the above-mentioned MFCs 241a to 241g, valves 243a to 243g, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotation mechanism 267, boat elevator 115, shutter opening / closing mechanism 115s, etc.

[0029] The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read a recipe from the storage device 121c in response to input of an operation command from the input / output device 122. The CPU 121a is configured to control, in accordance with the contents of the read recipe, the flow rate adjustment operation of various substances (various gases) by the MFCs 241a to 241g, the opening and closing operation of the valves 243a to 243g, the opening and closing operation of the APC valve 244 and the pressure adjustment operation by the APC valve 244 based on the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the rotation and rotation speed adjustment operation of the boat 217 by the rotation mechanism 267, the lifting and lowering operation of the boat 217 by the boat elevator 115, the opening and closing operation of the shutter 219s by the shutter opening and closing mechanism 115s, and the like.

[0030] The controller 121 can be configured by installing the above-mentioned program recorded and stored in the external storage device 123 into a computer. The external storage device 123 includes, for example, a magnetic disk such as an HDD, an optical disk such as a CD, a magneto-optical disk such as an MO, and a semiconductor memory such as a USB memory or an SSD. The storage device 121c and the external storage device 123 are configured as computer-readable recording media. Hereinafter, these will be collectively referred to as recording media. When the term recording medium is used in this specification, it may include only the storage device 121c alone, only the external storage device 123 alone, or both. Note that the program may be provided to the computer using a communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0031] (2) Substrate Processing Step An example of a series of processing sequences including a film formation process for forming a film on wafer 200 using the above-described substrate processing apparatus as one step in the manufacturing process of a semiconductor device will be described mainly with reference to Figures 4 to 7. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by controller 121.

[0032] <Pre-coating Process, Step S10> First, a pre-coating process for forming a pre-coating film in the processing chamber before the film forming process will be described. The pre-coating film may also be simply referred to as a film.

[0033] [Loading Empty Boat] In this step, with the empty boat 217 loaded into the processing vessel, a precoating process (also referred to as pre-coating) is performed to form a precoat film on the interior of the processing vessel, i.e., on the surfaces of components within the processing vessel, such as the inner wall of the reaction tube 203, the outer surfaces of the nozzles 249a to 249c, the inner surfaces of the nozzles 249a to 249c, the inner surface of the manifold 209, the surface of the boat 217, and the upper surface of the seal cap 219. Note that the precoating process may be performed with the boat 217 unloaded.

[0034] [Pre-coating Process] (First Process Gas Supply S11) In this step, a first process gas is supplied into the process chamber 201. Specifically, the valve 243a is opened to allow the first process gas to flow into the gas supply pipe 232a. The flow rate of the first process gas is adjusted by the MFC 241a, and the first process gas is supplied into the process chamber 201 via the nozzle 249a and exhausted from the exhaust port 233. At this time, the valve 243f is simultaneously opened to allow an inert gas to flow into the gas supply pipe 232a. Furthermore, at this time, in order to prevent the first process gas from entering the nozzles 249b and 249c, the valves 243e and 243g may be opened to allow the inert gas to flow into the gas supply pipes 232b and 232c.

[0035] At this time, a first process gas is supplied into the process vessel. Here, as the first process gas, for example, a metal-containing gas can be used. As the metal-containing gas, for example, a transition metal-containing gas can be used. As the transition metal-containing gas, for example, a titanium (Ti), tungsten (W), molybdenum (Mo), tantalum (Ta)-containing gas can be used. As the Ti-containing gas, for example, titanium tetrachloride (TiCl ４ ) gas, etc. can be used. Furthermore, as the metal-containing gas, for example, aluminum (Al), gallium (Ga), indium (In)-containing gas, etc. can be used. Furthermore, as the first processing gas, in addition to the metal-containing gas, for example, Si-containing gas, etc. can be used. As the first processing gas, one or more of these can be used.

[0036] The inert gas is nitrogen (N ２ Inert gases that can be used include rare gases such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, and xenon (Xe) gas. One or more of these gases can be used as the inert gas. This also applies to the steps described below.

[0037] (Purge S12) After a predetermined time has elapsed since the start of the supply of the first process gas, the valve 243a is closed to stop the supply of the first process gas into the process chamber 201. Then, the process chamber 201 is evacuated to remove gases remaining in the process chamber 201 (purging). At this time, the valves 243e, 243f, and 243g are opened to supply an inert gas into the process chamber 201. The inert gas acts as a purge gas.

[0038] (Second Process Gas Supply S13) Next, a second process gas is supplied into the process chamber 201. Specifically, the valve 243b is opened to allow the second process gas to flow into the gas supply pipe 232b. The flow rate of the second process gas is adjusted by the MFC 241b, and the second process gas is supplied into the process chamber 201 via the nozzle 249b and exhausted from the exhaust port 233. At this time, the valve 243e is simultaneously opened to allow an inert gas to flow into the gas supply pipe 232b. Furthermore, at this time, in order to prevent the second process gas from entering the nozzles 249a and 249c, the valves 243f and 243g may be opened to allow the inert gas to flow into the gas supply pipes 232a and 232c.

[0039] At this time, a second process gas is supplied into the process vessel. Here, the second process gas may be, for example, a nitriding gas. For example, ammonia (NH ３ ) gas, diazene (N ２ H ２ ) gas, hydrazine (N ２ H ４ ) gas, N ３ H ８ The second process gas may be one or more of these gases.

[0040] (Purge S14) After a predetermined time has elapsed since the start of the supply of the second process gas, the valve 243b is closed to stop the supply of the second process gas into the process chamber 201. Then, by the same process procedure as in the above-described purge S12, gases remaining in the process chamber 201 are removed from the process chamber 201 (purge).

[0041] (Performed a Predetermined Number of Times S15) By performing a cycle including the above-described steps S11 to S14, i.e., a cycle in which steps S11 to S14 are performed non-simultaneously, a predetermined number of times (X times, where X is 1 or an integer equal to or greater than 1), a film with a predetermined composition and a predetermined thickness can be formed on the member inside the processing vessel. Here, for example, a titanium nitride (TiN) film is formed.

[0042] (Third Process Gas Supply S16) Then, after performing a predetermined number of cycles of the above-described steps S11 to S14 in this order, a third process gas is supplied into the process chamber 201. Specifically, the valve 243c is opened to allow the third process gas to flow into the gas supply pipe 232c. The flow rate of the third process gas is adjusted by the MFC 241c, and the third process gas is supplied into the process chamber 201 via the nozzle 249c and exhausted from the exhaust port 233. At this time, the valve 243g is simultaneously opened to allow an inert gas to flow into the gas supply pipe 232c. At this time, in order to prevent the third process gas from entering the nozzles 249a and 249b, the valves 243f and 243e may be opened to allow the inert gas to flow into the gas supply pipes 232a and 232b.

[0043] At this time, a third process gas is supplied into the process container. Here, the third process gas may be, for example, a gas containing Si and H. The Si and H-containing gas may be, for example, monosilane (SiH ４ ) gas, disilane (Si ２ H ６ ) gas, trisilane (Si ３ H ８ As the third process gas, one or more of these gases may be used.

[0044] (Purge S17) After a predetermined time has elapsed since the start of the supply of the third process gas, the valve 243c is closed to stop the supply of the third process gas into the process chamber 201. Then, by the same process procedure as in the above-described purge S12, gases remaining in the process chamber 201 are removed from the process chamber 201 (purging).

[0045] (Performed a Predetermined Number of Times) A ​​cycle including the above-described steps S15 to S17, i.e., a cycle in which steps S15 to S17 are performed non-simultaneously, is performed a predetermined number of times (Y times, where Y is 1 or an integer equal to or greater than 2), to form a pre-coat film of a predetermined thickness on the components inside the processing vessel. Here, for example, a titanium silicon nitride (TiSiN) film is formed as the pre-coat film.

[0046] The pre-coating process is completed through the above series of operations. By forming the pre-coating film, adhesion to the inner wall of the processing vessel is improved, making it less likely to peel off from the inner wall. In addition, the surface roughness of the initial pre-coating film can be reduced.

[0047] Furthermore, the above-described pre-coating process can prevent the film thickness drop phenomenon from occurring during film formation, and can also prepare the environment and conditions inside the processing vessel before the next film formation process.

[0048] The supply order and timing of the first process gas, the second process gas, and the third process gas in the precoat process described above are not limited to the order and timing described above.

[0049] After the pre-coating process is completed, the seal cap 219 is lowered by the boat elevator 115 to open the lower end of the manifold 209. Then, the empty boat 217 is unloaded from the lower end of the manifold 209 to the outside of the reaction tube 203 (boat unloading).

[0050] <Film Forming Process, Step S20> Next, a film forming process will be described in which the wafers 200 are loaded into the processing furnace 202 and a film is formed on the wafers 200. That is, in this process, a film forming process is performed in which the wafers 200 are processed in a processing chamber.

[0051] The term "wafer" used in this specification may refer to the wafer itself or to a laminate of the wafer and a predetermined layer or film formed on its surface. The term "surface of a wafer" used in this specification may refer to the surface of the wafer itself or to the surface of a predetermined layer or the like formed on the wafer. When described in this specification, "forming a predetermined layer on a wafer" may mean forming a predetermined layer directly on the surface of the wafer itself or forming a predetermined layer on a layer or the like formed on the wafer. When used in this specification, the term "substrate" is synonymous with the term "wafer".

[0052] 1, when a plurality of wafers 200 are loaded into the boat 217 (wafer charge), the boat 217 supporting the plurality of wafers 200 is lifted by the boat elevator 115 and loaded into the processing chamber 201 (boat load). In this state, the seal cap 219 closes the lower end opening of the reaction tube 203 via the O-ring 220b.

[0053] The processing chamber 201, i.e., the space in which the wafer 200 is present, is evacuated by the vacuum pump 246 to a desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback-controlled (pressure adjustment) based on the measured pressure information. The processing chamber 201 is also heated by the heater 207 to a desired temperature. At this time, the amount of power supplied to the heater 207 is feedback-controlled (temperature adjustment) based on temperature information detected by the temperature sensor 263 so that the processing chamber 201 has a desired temperature distribution. The rotation mechanism 267 also starts rotating the wafer 200. The evacuation of the processing chamber 201 and the heating and rotation of the wafer 200 continue at least until the processing of the wafer 200 is completed.

[0054] [Film Formation Process] (First Process Gas Supply S21) In this step, a first process gas is supplied to the wafers 200 in the process chamber 201. Specifically, the valve 243a is opened to allow the first process gas to flow into the gas supply pipe 232a. The flow rate of the first process gas is adjusted by the MFC 241a, and the first process gas is supplied into the process chamber 201 via the nozzle 249a and exhausted from the exhaust port 233. At this time, the valve 243f is simultaneously opened to allow an inert gas to flow into the gas supply pipe 232a. Furthermore, at this time, in order to prevent the first process gas from entering the nozzles 249b and 249c, the valves 243e and 243g may be opened to allow the inert gas to flow into the gas supply pipes 232b and 232c.

[0055] At this time, the first process gas described above is supplied to the wafer 200 .

[0056] (Purge S22) After a predetermined time has elapsed since the start of the supply of the first processing gas, the valve 243a is closed to stop the supply of the first processing gas into the processing chamber 201. Then, by the same processing procedure as in the above-described purge S12, gases remaining in the processing chamber 201 are removed from the processing chamber 201 (purging).

[0057] (Second Process Gas Supply S23) Next, a second process gas is supplied to the wafers 200 in the process chamber 201. Specifically, the valve 243b is opened to allow the second process gas to flow into the gas supply pipe 232b. The flow rate of the second process gas is adjusted by the MFC 241b, and the second process gas is supplied into the process chamber 201 via the nozzle 249b and exhausted from the exhaust port 233. At this time, the valve 243e is simultaneously opened to allow an inert gas to flow into the gas supply pipe 232b. Furthermore, at this time, in order to prevent the second process gas from entering the nozzles 249a and 249c, the valves 243f and 243g may be opened to allow the inert gas to flow into the gas supply pipes 232a and 232c.

[0058] At this time, the second process gas described above is supplied to the wafers 200 .

[0059] (Purge S24) After a predetermined time has elapsed since the start of the supply of the second process gas, the valve 243b is closed to stop the supply of the second process gas into the process chamber 201. Then, by the same process procedure as in the above-described purge S12, gases remaining in the process chamber 201 are removed from the process chamber 201 (purge).

[0060] (Performed a Predetermined Number of Times) By performing a cycle including the above-described steps S21 to S24, i.e., a cycle in which steps S21 to S24 are performed non-simultaneously, a predetermined number of times (n times, where n is 1 or an integer equal to or greater than 2), a film with a predetermined composition and a predetermined thickness can be formed on wafer 200. The film T1 formed here is a polycrystalline film.

[0061] The film T1 formed here can be, for example, a metal-containing film, which is a film containing a metal element. Examples of the metal-containing film include a transition metal-containing film, which is a film containing a Group 3 to 11 transition metal element. Examples of the transition metal-containing film include a Ti-, W-, Mo-, or Ta-containing film. Examples of the transition metal-containing film include a transition metal nitride film. Examples of the transition metal nitride film include a tantalum nitride (TaN) film, a tungsten nitride (WN) film, a molybdenum nitride (MoN) film, and a titanium nitride (TiN) film. Examples of the film T1 include a simple film or nitride film of Al, Si, Ga, In, or the like.

[0062] (After-Purge and Atmospheric Pressure Return) After film formation is completed, an inert gas is supplied as a purge gas from each of the nozzles 249a to 249c into the processing chamber 201 and exhausted from the exhaust port 233. This purges the processing chamber 201, and gases and reaction by-products remaining in the processing chamber 201 are removed from the processing chamber 201 (after-purge). Thereafter, the atmosphere in the processing chamber 201 is replaced with the inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure (atmospheric pressure return).

[0063] [Wafer Unloading] The seal cap 219 is lowered by the boat elevator 115, and the lower end of the manifold 209 is opened. Then, the processed wafers 200, supported by the boat 217, are unloaded from the lower end of the manifold 209 to the outside of the reaction tube 203 (boat unloading). After the boat unloading, the shutter 219s is moved, and the opening at the lower end of the manifold 209 is sealed by the shutter 219s via the O-ring 220c (shutter close). After being unloaded to the outside of the reaction tube 203, the processed wafers 200 are removed from the boat 217 (wafer discharge).

[0064] When the above-described film formation process is performed, a film T1 is formed and accumulates as deposits inside the processing vessel, i.e., on the surfaces of components inside the processing vessel, such as the inner wall of the reaction tube 203, the outer surfaces of the nozzles 249a-249c, the inner surfaces of the nozzles 249a-249c, the inner surface of the manifold 209, the surface of the boat 217, and the upper surface of the seal cap 219. If the amount of deposits, i.e., the cumulative film thickness of the film T1, becomes too thick, peeling of the deposited film may occur, and the amount of particles generated may increase. For this reason, a cleaning process may be performed to remove all of the deposited film inside the processing vessel before peeling of the deposited film occurs, and a pre-coat film may be formed inside the processing vessel from which all of the deposited film has been removed. In this case, the cleaning process and the time required to form the pre-coat film are long, which may reduce productivity.

[0065] In the embodiment of the present disclosure, a first cleaning process is performed each time the film formation process S20 is performed, i.e., each time a substrate is processed, to clean (also referred to as etching) the surface of the film T1 formed in the processing chamber. Then, a second cleaning process is performed to remove the deposited film in the processing chamber when the cumulative film thickness in the processing chamber reaches a predetermined value or greater. This shortens the cleaning time and improves productivity. Here, the cumulative film thickness refers to the thickness of the film formed in the film formation process. When the first cleaning process is performed, the cumulative film thickness is calculated by subtracting the amount etched in the first cleaning process from the thickness of the film formed in the processing chamber. That is, the cumulative film thickness is calculated by pre-storing the film thickness formed on the wafer 200 in one film formation process and the amount etched in the first cleaning process. Each time the film formation process and the first cleaning process are performed, the number of times each process is counted to estimate the cumulative film thickness formed in the processing chamber. Alternatively, the cumulative film thickness may be calculated using an actual measurement. Alternatively, the cumulative film thickness may be calculated based on at least one of the processing time, the flow rate of the gas used in the film formation process and the first cleaning process, and the pressure in the processing chamber 201.

[0066] <Determination step, step S30> Next, it is determined whether the cumulative film thickness is equal to or greater than a predetermined value. If the cumulative film thickness is smaller than the predetermined value, a first cleaning step S40 (described later) is performed. If the cumulative film thickness is equal to or greater than the predetermined value, a second cleaning step S50 (described later) is performed.

[0067] <First Cleaning Process, Step S40> In this process, an empty boat 217 is loaded into the process chamber 201, and a first cleaning process (also referred to as an etching process) is performed, which can remove (also referred to as etching) at least a portion of the film T1 formed in the process container. The first cleaning process can also be called simple cleaning or light cleaning that is performed in a short time after each film formation process.

[0068] [Loading Empty Boat] The shutter 219s is moved by the shutter opening / closing mechanism 115s, and the lower end opening of the manifold 209 is opened (shutter open). Thereafter, the empty boat 217, i.e., the boat 217 not loaded with wafers 200, is lifted by the boat elevator 115 and loaded into the processing chamber 201. In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b. Note that the first cleaning process may be performed with the boat 217 unloaded.

[0069] After the empty boat 217 has been loaded into the processing chamber 201, the processing chamber 201 is evacuated by the vacuum pump 246 so that the interior of the processing chamber 201 reaches a desired pressure. The interior of the processing chamber 201 is heated by the heater 207 so that the interior of the processing chamber 201 reaches a desired temperature. The rotation mechanism 267 starts to rotate the boat 217. The operation of the vacuum pump 246, the heating of the interior of the processing chamber 201, and the rotation of the boat 217 continue at least until this step is completed. The boat 217 does not necessarily have to be rotated. The processing temperature in this step is set to 400 to 500° C., the same as the processing temperature in the film-forming step S20 described above. The processing pressure in this step is set to be lower than the processing pressure in the film-forming step S20.

[0070] In this specification, the processing temperature refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201, and the processing pressure refers to the pressure inside the processing chamber 201. Furthermore, the processing time refers to the time the processing continues. These terms also apply to the following explanations. Furthermore, in this specification, the notation of a numerical range such as "400 to 500°C" means that the lower limit and the upper limit are included in the range. Therefore, for example, "400 to 500°C" means "400°C or higher and 500°C or lower." The same applies to other numerical ranges.

[0071] [First Cleaning Process] The first cleaning process is performed by carrying out the following treatment process S41, cleaning process S42, and purge process S43 a predetermined number of times (m times, where m is 1 or an integer of 2 or more).

[0072] When the film formation process S20 is performed, a film T1 is deposited on the surface of the reaction tube 203, etc., as shown in FIG. 6A. The deposited film T1 is a polycrystalline film with columnar crystals. Therefore, when a cleaning gas is supplied to the film T1 in this state and a cleaning process is performed, the cleaning gas may penetrate the grain boundaries, causing the film T1 to be scraped (etched) from the grain boundaries, as shown in FIG. 6B. This may result in an uneven surface of the film T1, resulting in increased surface roughness (surface roughness). If the surface roughness of the film T1 is large, the surface area within the processing chamber may increase, resulting in different amounts of processing gas consumed within the processing chamber. This may result in different amounts of processing gas supplied to the wafer 200, resulting in uneven film thicknesses on the wafer 200. Furthermore, the film may partially peel off from the processing chamber, generating particles.

[0073] In the present disclosure, a treatment process is performed before the cleaning process in the first cleaning process. As a result, a second film T2 is formed on the surface including the grain boundaries of a polycrystalline film T1 formed in a processing vessel. In other words, the surface including the grain boundaries of the film T1 is modified by the treatment gas, and the film T2 is formed on the surface including the grain boundaries of the film T1. In this way, it is possible to prevent the grain boundaries of the film T1 from being exposed to the cleaning gas.

[0074] That is, by performing the treatment process, as shown in FIG. 7A, a film T2 is formed on the surface, including the grain boundaries, of the film T1 deposited on the surface of the reaction tube 203, etc., as shown in FIG. 7B. That is, the film T2 is formed so as to fill the grain boundaries of the film T1. In this way, by allowing the components of the treatment gas to penetrate the grain boundaries of the film T1, etching from the grain boundaries of the film T1 during the cleaning process of the film T1 can be suppressed. As a result, the film T1 is etched from above by the first cleaning process described below, improving the surface roughness of the film and enabling the amount of process gas consumed by the wafer 200 to be uniform for each wafer when processing the wafer 200. Here, "per wafer" includes either or both of per wafer when processing multiple wafers in a single process and per wafer for each substrate process (also referred to as per batch processing).

[0075] (Treatment Process S41) First, a third process gas is supplied into the process chamber 201. Specifically, the valve 243c is opened to allow the third process gas to flow into the gas supply pipe 232c. The flow rate of the third process gas is adjusted by the MFC 241c, and the third process gas is supplied into the process chamber 201 via the nozzle 249c and exhausted from the exhaust port 233. At this time, the valve 243g is simultaneously opened to allow an inert gas to flow into the gas supply pipe 232c. Furthermore, at this time, in order to prevent the third process gas from entering the nozzles 249a and 249b, the valves 243f and 243e may be opened to allow the inert gas to flow into the gas supply pipes 232a and 232b.

[0076] In this step, for example, a third treatment gas is supplied into the treatment vessel as a treatment gas. The treatment gas in this step may be supplied continuously or in portions. The treatment gas may be a gas that can form a film by itself or a gas that can change the surface state of the target film. For example, a Si-containing gas may be used as the treatment gas. For example, SiH ４ Gas, Si ２ H ６ Gas, Si ３ H ８ In addition to the Si-containing gas, for example, an oxidizing gas, a metal-containing gas, or the like can be used. As the oxidizing gas, for example, oxygen (O ２ ) gas, ozone (O ３ ) gas, water vapor (H ２ O) gas, hydrogen peroxide (H ２ O ２ ) gas, hydrogen (H ２ ) and O ２ mixed gas, nitrous oxide (N ２ O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO ２ ) gas, etc. At least one of these gases can be used as the oxidizing gas. Examples of the metal-containing gas include hafnium chloride (HfCl ４ ) gas, zirconium chloride (ZrCl ４ ) gas, tungsten hexafluoride (WF ６ ) gas, tungsten hexachloride (WCl ６ ) gas, molybdenum pentachloride (MoCl ５ ) gas, molybdenum dichloride dioxide (MoO ２ Cl ２ ) gas, molybdenum oxide tetrachloride (MoOCl ４ ) gas, molybdenum hexafluoride (MoF ６ ) gas, molybdenum dioxide difluoride (MoO ２ F ２ ) gas, molybdenum tetrafluoride oxide (MoOF ４) gas, etc. can be used. One or more of these can be used as the treatment gas. A gas capable of filling the grain boundaries of the film to be cleaned is preferred as the treatment gas. In other words, a gas capable of forming a film on the grain boundaries is preferred. Examples of gases capable of forming a film on the grain boundaries include the Si-containing gas and metal-containing gas disclosed herein. Note that while it is difficult for an oxidizing gas to form a film by itself, oxidizing the surface of the film to be cleaned (especially the grain boundaries) can sometimes lower the etching rate of the oxidized portion. In this case, etching proceeds from other portions of the grain boundaries, which can sometimes improve roughness. More preferably, a gas that seals the halogen element in the film inside the treatment vessel is preferred, and a gas that does not contain a halogen element is used. In the example of the present disclosure, for example, a silane-based gas or an oxidizing gas is used.

[0077] Furthermore, the treatment gas is supplied to the film T1 in a state where it is decomposed. This modifies the surface of the film T1, forming a film T2. Here, the state where the treatment gas is decomposed includes, for example, supplying the treatment gas at a temperature equal to or higher than the decomposition temperature of the treatment gas. Furthermore, the state where the treatment gas is decomposed refers, for example, to a state where the film T1 is composed of a catalyst for the treatment gas. That is, the film T1 is preferably a film that serves as a catalyst for the treatment gas. By performing the treatment in a state where the treatment gas is decomposed, elements contained in the treatment gas can be precipitated at the grain boundaries of the film T1. Furthermore, by supplying the treatment gas to a film that serves as a catalyst, the temperature adjustment time during substrate processing, cleaning processing, etching processing, and treatment processing (also referred to as modification processing) can be shortened. This improves the throughput of the semiconductor device manufacturing process.

[0078] The film T2 formed here is a film with lower crystallinity than the film T1, such as an amorphous film. This allows the crystal grain boundaries of the polycrystalline film T1 to be filled with the film T2. Furthermore, the etching rate of the film T2 when a cleaning gas is supplied (second etching rate) is equal to or less than the etching rate of the film T1 when a cleaning gas is supplied (first etching rate). Preferably, the etching rate of the film T2 when a cleaning gas is supplied is set to be smaller than the etching rate of the film T1 when a cleaning gas is supplied. Furthermore, the thickness of the film T2 formed here is set to be thinner than the thickness of the film T1. As a result, the film T1 is etched from above by the first cleaning process described below, improving the surface roughness of the film.

[0079] Furthermore, a film containing, for example, a Group 13 to 16 element is formed as the film T2. As the film containing a Group 13 to 16 element, for example, a film containing Si, boron (B), oxygen (O), or phosphorus (P) can be used. As the film containing Si, B, O, or P, for example, a silicon nitride (SiN) film, a silicon oxide (SiO) film, a TiSiN film, a B film, a boron nitride (BN) film, a P film, or a TiPN film can be used.

[0080] Specifically, the treatment gas may be, for example, SiH ４ When gas is used, SiH ４ The decomposition temperature of the gas is, for example, 350 to 400° C. Furthermore, when a TiN film is used as the film T1, SiH ４ The gas is easily decomposed, and the TiN film is ４ This is a membrane that acts as a catalyst.

[0081] (Cleaning Process S42) Next, a cleaning gas is supplied into the processing chamber 201. Specifically, the valve 243d is opened to allow the cleaning gas to flow into the gas supply pipe 232a. The cleaning gas has its flow rate adjusted by the MFC 241d, is supplied into the processing chamber 201 via the nozzle 249a, and is exhausted from the exhaust pipe 231. At this time, the valve 243f is simultaneously opened to allow an inert gas to flow into the gas supply pipe 232a. Furthermore, at this time, in order to prevent the cleaning gas from entering the nozzles 249b and 249c, the valves 243e and 243g may be opened to allow the inert gas to flow into the gas supply pipes 232b and 232c.

[0082] The cleaning gas may be, for example, a halogen-based gas. Examples of the halogen-based gas include nitrogen trifluoride (NF ３ ) gas, fluorine (F ２ ) gas, chlorine (Cl ２ ) gas, hydrogen fluoride (HF) gas, chlorine trifluoride (ClF ３ ) gas, hydrogen chloride (HCl) gas, boron trichloride (BCl ３ ) gas, bromine (Br ２ ) gas, etc. As the cleaning gas, one or more of these gases can be used.

[0083] As a result, the cleaning gas is supplied to the film T1 having the film T2 formed on the surface including the grain boundaries, and at least a portion of the film T1 is removed.

[0084] After a predetermined time has elapsed and the first cleaning process in the processing chamber 201 has been completed, the valve 243d is closed to stop the supply of the cleaning gas into the processing chamber 201.

[0085] (Purge S43) After a predetermined time has elapsed since the start of the supply of the third process gas, the valve 243c is closed to stop the supply of the third process gas into the process chamber 201. Then, by the same processing procedure as the purging in the above-described purge S12, gases remaining in the process chamber 201 are removed from the process chamber 201 (purging).

[0086] (Performed a predetermined number of times) By performing a cycle including the above-mentioned S41 to S43, i.e., a cycle in which S41 to S43 are performed non-simultaneously, a predetermined number of times (m times, where m is an integer of 1 or 2 or more), the film T1 in the processing container is etched to a predetermined thickness.

[0087] Examples of processing conditions for the first cleaning (etching) process include: cleaning gas supply flow rate: 0.1 to 10 slm inert gas supply flow rate (each gas supply pipe): 0 to 10 slm each gas supply time: 5 to 300 seconds, preferably 100 to 200 seconds processing temperature: 200°C or higher and lower than 900°C, preferably 300 to 800°C, more preferably 350 to 600°C processing pressure: 150 to 400 Pa, preferably 200 to 300 Pa. Note that when the supply flow rate includes 0 slm, 0 slm means that the gas is not supplied. This also applies to other explanations in this disclosure.

[0088] The first cleaning process is completed through the above series of operations.

[0089] Furthermore, when forming a TiN film, for example, in the film forming step S20, abnormally grown nuclei grow along with the crystal growth of TiN. In this step, the abnormally grown nuclei formed on the surface of the TiN film in the processing vessel are removed (etched). As a result, the surface of the TiN film formed in the processing vessel is etched and planarized.

[0090] [Empty Boat Unloading] After the first cleaning process is completed, the seal cap 219 is lowered by the boat elevator 115, and the lower end of the manifold 209 is opened. Then, the empty boat 217 is unloaded from the lower end of the manifold 209 to the outside of the reaction tube 203 (boat unloading). After the boat unloading, the shutter 219s is moved, and the lower end opening of the manifold 209 is sealed by the shutter 219s via the O-ring 220c (shutter closing). Then, the next plurality of wafers 200 are loaded into the boat 217, and the above-described film formation process S20 is performed.

[0091] <Second Cleaning Process, Step S50> In this process, an empty boat 217 is loaded into the processing chamber 201, and a second cleaning process is performed to remove the deposition film and pre-coat film deposited on the inner walls of the processing vessel, etc., over a longer period of time than the first cleaning process described above. That is, the cycle of steps S41 to S43 described above is performed a predetermined number of times (m times, where m is an integer of 1 or 2 or greater), and when the cumulative film thickness inside the processing vessel reaches a predetermined value or greater, the second cleaning process is performed. This removes the film deposited inside the processing vessel.

[0092] [Loading Empty Boat] The shutter 219s is moved by the shutter opening / closing mechanism 115s, and the lower end opening of the manifold 209 is opened (shutter open). Thereafter, the empty boat 217, i.e., the boat 217 not loaded with wafers 200, is lifted by the boat elevator 115 and loaded into the processing chamber 201. In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b. Note that the second cleaning process may be performed with the boat 217 unloaded.

[0093] After the empty boat 217 has been carried into the processing chamber 201, the processing chamber 201 is evacuated by the vacuum pump 246 so that the interior of the processing chamber 201 reaches a desired pressure. The interior of the processing chamber 201 is heated by the heater 207 so that the interior of the processing chamber 201 reaches a desired temperature. The rotation mechanism 267 also starts to rotate the boat 217. The operation of the vacuum pump 246, the heating of the interior of the processing chamber 201, and the rotation of the boat 217 continue at least until this step is completed. The boat 217 does not necessarily have to be rotated.

[0094] [Second Cleaning Process] In this process, the cleaning gas described above is supplied into the processing chamber 201. Specifically, the valve 243d is opened to allow the cleaning gas to flow into the gas supply pipe 232a. The cleaning gas has a flow rate adjusted by the MFC 241d, is supplied into the processing chamber 201 via the nozzle 249a, and is exhausted from the exhaust pipe 231. At this time, the valve 243f may be opened at the same time to allow an inert gas to flow into the gas supply pipe 232a. Furthermore, at this time, in order to prevent the cleaning gas from entering the nozzles 249b and 249c, the valves 243e and 243g may be opened to allow the inert gas to flow into the gas supply pipes 232b and 232c.

[0095] After a predetermined time has elapsed and the second cleaning process in the processing chamber 201 has been completed, the valve 243d is closed to stop the supply of cleaning gas into the processing chamber 201. That is, the cleaning gas is supplied into the processing vessel in which the film to be cleaned is formed for a longer period of time than the supply period of cleaning gas during the first cleaning process. Then, the processing chamber 201 is purged (purging) using a processing procedure similar to the above-described purge S12. Thereafter, the atmosphere in the processing chamber 201 is replaced with an inert gas (inert gas replacement).

[0096] The second cleaning process is completed through the above series of operations.

[0097] [Empty Boat Removal] After the second cleaning process is completed, the seal cap 219 is lowered by the boat elevator 115, and the lower end of the manifold 209 is opened. Then, the empty boat 217 is removed from the lower end of the manifold 209 to the outside of the reaction tube 203 (boat unloading). After the boat unloading, the shutter 219s is moved, and the lower end opening of the manifold 209 is sealed by the shutter 219s via the O-ring 220c (shutter closing).

[0098] After the second cleaning step S50, the precoating step S10 is performed to form a precoat film inside the processing container. That is, the inside of the processing container is precoated.

[0099] In this process, when the thickness of the deposition film deposited in the processing vessel reaches a predetermined value or more, a second cleaning process is performed. Here, in the second cleaning process, the deposition film deposited in the processing vessel and the pre-coat film are etched. That is, by performing the second cleaning process, even the pre-coat film formed in the processing vessel is etched.

[0100] That is, when the cumulative film thickness in the processing vessel after the substrate processing is smaller than a predetermined value, the first cleaning process is performed in a short time, and when the cumulative film thickness in the processing vessel after the substrate processing is equal to or greater than the predetermined value, the second cleaning process is performed. This allows for efficient cleaning in a short time compared to when the first cleaning process is not performed.

[0101] (3) Other Embodiments The above describes specific embodiments of the present disclosure. However, the present disclosure is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit and scope of the present disclosure. In other embodiments described below, elements that are used in the same manner as the substrate processing apparatus shown in FIG. 1 and that are substantially the same as the elements described in FIG. 1 and processes that are substantially the same as the processes shown in FIGS. 4, 5, etc. are denoted by the same reference numerals, and descriptions thereof will be omitted.

[0102] (Second Aspect) Next, another aspect of the above-described first cleaning process will be described with reference to FIG. 8 . In this aspect, the first cleaning process is performed by performing the cleaning process S411, the purging process S412, and the treatment process S413 a predetermined number of times (m times, where m is an integer of 1 or greater). That is, the order of the processes is different from that of the first cleaning process described above. Note that the cleaning process S411, the purging process S412, and the treatment process S413 are performed in the same manner as the above-described cleaning process S42, the purging process S43, and the treatment process S41.

[0103] This embodiment also provides the same effects as the above-described embodiment. In this embodiment, from the second cycle onward, the cleaning process is performed after the treatment process, so that the deterioration of the surface roughness of the film T1 can be improved, as in the above-described embodiment. Furthermore, in this embodiment, the treatment process S413 is performed at the end of the first cleaning process, so that components contained in the cleaning gas can be prevented from remaining in the reaction tube 203. That is, in the next film formation process S20, it is possible to prevent components contained in the cleaning gas from being adsorbed onto the wafer 200.

[0104] (Third Aspect) Next, yet another aspect of the second cleaning process will be described with reference to Fig. 9. In this aspect, the treatment process S44 is performed after the treatment process S41, cleaning process S42, and purging process S43 in the above-described aspect have been performed a predetermined number of times (m times, where m is an integer of 1 or greater). That is, the treatment process S44 is performed after the process shown in Fig. 5 has been performed. The treatment process S44 is performed in the same manner as the treatment process S41 described above. That is, the treatment process is performed before and after the cleaning process.

[0105] In this embodiment, as in the above-described embodiment, the deterioration of the surface roughness of the film T1 can be improved. In this embodiment, it is further possible to prevent components contained in the cleaning gas from remaining in the reaction tube 203. That is, it is possible to prevent components contained in the cleaning gas from being adsorbed onto the wafer 200 in the next film formation step S20.

[0106] Although the above-described embodiment has been described with reference to an example in which a film T1 formed in a processing chamber is cleaned (etched), the present disclosure is not limited thereto and can also be suitably applied to etching a film T1 formed on a wafer 200. That is, the present disclosure can also be suitably applied to etching a film T1 formed on a wafer 200 by forming a film T2 on a surface including the grain boundaries of the film T1 formed on the wafer 200. This embodiment can also reduce the surface roughness of a film formed on the surface of the wafer 200. This can improve the uniformity of the film formed on the surface of the wafer 200, thereby improving the characteristics of the semiconductor device. The present embodiment can be applied to a product substrate, a dummy substrate, or both. A product substrate is a substrate used as a semiconductor device. Applying this embodiment to a film formed on a product substrate can improve the surface roughness of a film forming a structure of a semiconductor device. A dummy substrate is a substrate used when processing a product substrate. A dummy substrate can be, for example, a monitor substrate used for inspection or a fill dummy substrate used to uniform gas consumption. By applying this embodiment to a film formed on a dummy substrate, the gas consumption amount in the dummy substrate can be made uniform for each substrate processing, thereby making it possible to make the consumption amount of the processing gas supplied to each product substrate uniform.

[0107] Furthermore, it is preferable that recipes used for each process are individually prepared according to the process content and stored in the storage device 121c via an electric communication line or the external storage device 123. Then, when starting each process, it is preferable that the CPU 121a appropriately selects an appropriate recipe according to the process content from among the multiple recipes recorded and stored in the storage device 121c. This makes it possible to reproducibly form films with various film types, composition ratios, film qualities, and film thicknesses using a single substrate processing apparatus. It also reduces the burden on the operator, avoids operational errors, and enables each process to be started quickly.

[0108] The above-mentioned recipes do not necessarily have to be newly created, but may be prepared by modifying an existing recipe already installed in the substrate processing apparatus. When modifying a recipe, the modified recipe may be installed in the substrate processing apparatus via an electric communication line or a recording medium on which the modified recipe is recorded. Alternatively, an existing recipe already installed in the substrate processing apparatus may be directly modified by operating the input / output device 122 provided in the existing substrate processing apparatus.

[0109] In the above-described embodiment, an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at a time has been described. The present disclosure is not limited to the above-described embodiment and can be suitably applied, for example, to a case where a film is formed using a single-wafer substrate processing apparatus that processes one or several substrates at a time. In the above-described embodiment, an example of forming a film using a substrate processing apparatus having a hot-wall processing furnace has been described. The present disclosure is not limited to the above-described embodiment and can be suitably applied to a case where a film is formed using a substrate processing apparatus having a cold-wall processing furnace.

[0110] Even when using these substrate processing apparatuses, each process can be performed using the same processing procedures and conditions as those in the above-mentioned and other embodiments, and the same effects as those in the above-mentioned and other embodiments can be obtained.

[0111] The above-described and other embodiments may be used in combination as appropriate. In this case, the processing procedures and processing conditions may be the same as those in the above-described and other embodiments, for example.

[0112] 200 Wafer (substrate) 203 Reaction tube

Claims

1. A processing method comprising: (a) a step of forming a second film on a first film, the second film having an etching rate, when a first gas capable of removing at least a portion of the first film is supplied, which has a second etching rate equal to or lower than the first etching rate of the first film; and (b) a step of supplying the first gas to the first film.

2. The method of claim 1, wherein said second etch rate is less than said first etch rate.

3. The method of claim 1, wherein (a) is carried out before or after (b).

4. The method of claim 1, wherein steps (a) and (b) are performed a predetermined number of times.

5. The method according to claim 1, further comprising the step of removing said first film by supplying said first gas after carrying out (a) and (b) a predetermined number of times.

6. The processing method according to claim 1, wherein the first film is a film containing a metal element.

7. The method according to claim 6, wherein the metal element is a transition metal element.

8. The process of claim 1, wherein said second film comprises a Group 13 to 16 element.

9. The processing method according to claim 1, wherein the first film and the second film are formed in a processing vessel.

10. The method of claim 1, wherein said first film and said second film are formed on a substrate.

11. The method of claim 1, wherein said first film is a polycrystalline film and said second film is a film having a lower crystallinity than said first film.

12. The process of claim 1, wherein said first film is a polycrystalline film and said second film is an amorphous film.

13. The method of claim 1, wherein the thickness of said second film is less than the thickness of said first film.

14. The processing method according to claim 1, wherein in (a), the second film is formed by supplying a second gas to the first film in a state in which the second gas is decomposed.

15. The method of claim 14, wherein the conditions under which the second gas is decomposed include a temperature equal to or higher than the decomposition temperature of the second gas.

16. The method of claim 14, wherein the condition in which the second gas is decomposed is a condition in which the first film comprises a catalyst for the second gas.

17. A processing apparatus having: a first gas supply system capable of supplying a first gas capable of removing at least a portion of a first film; and a control unit configured to be capable of controlling the first gas supply system to perform: (a) a process of forming a second film on the first film, the second film having an etching rate, when the first gas is supplied, that is a second etching rate that is equal to or lower than a first etching rate of the first film; and (b) a process of supplying the first gas to the first film.

18. A method for manufacturing a semiconductor device, comprising: (a) a step of forming a second film on a first film, the second film having an etching rate, when a first gas capable of removing at least a portion of the first film is supplied, which has a second etching rate that is equal to or lower than the first etching rate of the first film; and (b) a step of supplying the first gas to the first film.

19. (a) a step of forming a second film on a first film, the second film having an etching rate, when a first gas capable of removing at least a portion of the first film is supplied, which is a second etching rate equal to or lower than the first etching rate of the first film; and (b) a step of supplying the first gas to the first film. A program for causing a processing device to execute the steps by a computer.