Cleaning method, semiconductor device manufacturing method, substrate processing apparatus, and recording medium

Abstract

The present application relates to a cleaning method, a method for manufacturing a semiconductor device, a substrate processing apparatus, and a recording medium. The cleaning effect within a processing container is improved. The method comprises a step of removing substances adhered to the processing container by performing a cycle comprising the following steps at a first temperature a predetermined number of times: (a) supplying one of a nitrogen- and hydrogen-containing gas and a fluorine-containing gas into the processing container after substrate processing; and (b) supplying another gas, different from the nitrogen- and hydrogen-containing gas and the fluorine-containing gas, into the processing container in which one of the gases remains.

Description

Technical Field

[0001] The present invention relates to a cleaning method, a method for manufacturing a semiconductor device, a substrate processing apparatus, and a recording medium. Background Art

[0002] As one of the steps in the manufacturing process of a semiconductor device, there is a step of cleaning the inside of a processing container after processing a substrate (for example, see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2011-134781 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] The object of the present invention is to improve the cleaning effect inside a processing container.

[0008] Means for solving problems

[0009] One aspect of the present invention provides a technique for removing substances adhered to the inside of the processing container by performing a cycle including the following steps at a first temperature a predetermined number of times:

[0010] (a) supplying one of a nitrogen- and hydrogen-containing gas and a fluorine-containing gas into a processing container after processing the substrate; and

[0011] (b) A step of supplying a gas different from the one gas, from among the nitrogen- and hydrogen-containing gas and the fluorine-containing gas, into the processing container in a state where the one gas remains.

[0012] Effects of the Invention

[0013] According to the present invention, the cleaning effect inside the processing container can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 1 is a schematic diagram of the structure of a vertical processing furnace of a substrate processing apparatus preferably used in one embodiment of the present invention, and shows a processing furnace 202 portion in a vertical cross-sectional view.

[0015] Figure 2 This is a schematic diagram of a vertical processing furnace of a substrate processing device preferably used in one embodiment of the present invention. Figure 1 A cross-sectional view taken along line AA shows a portion of the processing furnace 202 .

[0016] Figure 31 is a schematic diagram of the configuration of a controller 121 of a substrate processing apparatus preferably used in one embodiment of the present invention, and is a diagram showing a control system of the controller 121 in the form of a block diagram.

[0017] Figure 4 This is a diagram showing gas supply timing in substrate processing according to one embodiment of the present invention.

[0018] Figure 5 1 and 2 are diagrams respectively showing the gas supply timing, the set pressure, and the set temperature in the processing chamber in the cleaning process according to one embodiment of the present invention. DETAILED DESCRIPTION

[0019] <One embodiment of the present invention>

[0020] The following mainly refers to Figures 1 to 5 One embodiment of the present invention will be described. It should be noted that the drawings used in the following description are schematic, and the dimensional relationships and ratios of the elements in the drawings may not necessarily be consistent with actual dimensions. Furthermore, the dimensional relationships and ratios of the elements in the drawings may not necessarily be consistent across multiple drawings.

[0021] (1) Configuration of substrate processing apparatus

[0022] like Figure 1 As shown, the processing furnace 202 has a heater 207 as a temperature control unit (heating unit). The heater 207 is cylindrical and is vertically mounted by being supported by a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) the gas using heat.

[0023] A reaction tube 203 is arranged concentrically with the heater 207 inside the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and has a cylindrical shape with a closed top and an open bottom. Below the reaction tube 203, a manifold 209 is arranged concentrically with 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 is configured to engage with and support the lower end of the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a sealing member. The reaction tube 203 is mounted vertically, similar to the heater 207. The reaction tube 203 and the manifold 209 primarily constitute a processing vessel (reaction container). A processing chamber 201 is formed within the hollow portion of the processing container. The processing chamber 201 is configured to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed in the processing chamber 201 .

[0024] Nozzles 249a to 249c, serving as first to third supply units, are provided within the processing chamber 201, extending through the sidewalls of the manifold 209. These nozzles 249a to 249c are also referred to as the first to third nozzles, respectively. These nozzles 249a to 249c are made of a heat-resistant material such as quartz or SiC. Gas supply pipes 232a to 232c are connected to these nozzles, respectively. These nozzles 249a to 249c are separate nozzles, and nozzles 249a and 249c are each located adjacent to nozzle 249b.

[0025] Gas supply pipes 232a to 232c are provided, in order from the upstream side of the gas flow, with mass flow controllers (MFCs) 241a to 241c, serving as flow controllers (flow control units), and valves 243a to 243c, serving as on-off valves. Gas supply pipes 232d and 232f are connected to gas supply pipe 232a downstream of valve 243a, respectively. Gas supply pipes 232e and 232g are connected to gas supply pipe 232b downstream of valve 243b, respectively. Gas supply pipe 232h is connected to gas supply pipe 232c downstream of valve 243c. MFCs 241d to 241h and valves 243d to 243h are provided, in order from the upstream side of the gas flow. Gas supply pipes 232a to 232h are made of a metal material, such as SUS.

[0026] like Figure 2As shown, nozzles 249a-249c are positioned in the annular space between the inner wall of reaction tube 203 and wafers 200, rising upward from the bottom to the top of the inner wall of reaction tube 203 in the direction in which wafers 200 are arranged. Specifically, nozzles 249a-249c are positioned along the wafer arrangement area, lateral to and horizontally surrounding the wafer arrangement area where wafers 200 are arranged. When viewed from above, nozzle 249b is positioned so as to align with exhaust port 231a (described later) across the center of wafer 200 loaded into processing chamber 201. Nozzles 249a and 249c are positioned so as to sandwich a straight line L passing through the centers of nozzle 249b and exhaust port 231a along the inner wall of reaction tube 203 (the outer periphery of wafer 200). Line L also passes through nozzle 249b and the center of wafer 200. That is, nozzle 249c can also be positioned on the opposite side of nozzle 249a with line L interposed therebetween. Nozzles 249a and 249c are symmetrically arranged with line L as the axis of symmetry. Gas supply holes 250a to 250c for supplying gas are provided on the side surfaces of nozzles 249a to 249c, respectively. Gas supply holes 250a to 250c are each opened so as to face exhaust port 231a when viewed from above, and are capable of supplying gas to wafer 200. A plurality of gas supply holes 250a to 250c are provided from the bottom to the top of reaction tube 203.

[0027] As a processing gas, for example, a raw material (raw material gas) is supplied from the gas supply pipe 232a via the MFC 241a, the valve 243a, and the nozzle 249a into the processing chamber 201. Specifically, a silane-based gas containing silicon (Si), which is the main element constituting the film formed on the wafer 200, can be used. As the silane-based gas, for example, a gas containing Si and a halogen, that is, a halosilane-based gas can be used. Halogens include chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc. As the halosilane-based gas, for example, a chlorosilane-based gas containing Si and Cl can be used.

[0028] As a cleaning gas, for example, a gas containing nitrogen (N) and hydrogen (H) is supplied from gas supply pipe 232b via MFC 241b, valve 243b, and nozzle 249b into process chamber 201. While N and H containing gases alone cannot achieve a practical cleaning effect, in this embodiment, they are mixed with a F containing gas (described later) under specific conditions to improve the efficiency of the cleaning process. Therefore, it is conceivable to include N and H containing gases in the cleaning gas in the same manner as the F containing gas.

[0029] As the processing gas, for example, a gas containing oxygen (O) as an oxidizing gas (oxidant) is supplied from the gas supply pipe 232 c into the processing chamber 201 via the MFC 241 c , the valve 243 c , and the nozzle 249 c .

[0030] As the cleaning gas, for example, a F-containing gas is supplied from the gas supply pipe 232 d into the processing chamber 201 via the MFC 241 d , the valve 243 d , the gas supply pipe 232 a , and the nozzle 249 a .

[0031] As a process gas, for example, H-containing gas is supplied as a reducing gas (reducing agent) from gas supply pipe 232e via MFC 241e, valve 243e, gas supply pipe 232b, and nozzle 249b into process chamber 201. H-containing gas alone cannot achieve an oxidizing effect, but by reacting with O-containing gas under specific conditions, it generates oxidizing species such as atomic oxygen (O), thereby improving the efficiency of the oxidation process. Therefore, it is conceivable to include H-containing gas in the oxidizing gas, similarly to O-containing gas.

[0032] The inert gas is supplied from the gas supply pipes 232f to 232h through the MFCs 241f to 241h, valves 243f to 243h, gas supply pipes 232a to 232c, and nozzles 249a to 249c into the processing chamber 201. The inert gas functions as a purge gas, carrier gas, dilution gas, and the like.

[0033] The silane gas supply system primarily comprises gas supply pipe 232a, MFC 241a, and valve 243a. The N- and H-containing gas supply system primarily comprises gas supply pipe 232b, MFC 241b, and valve 243b. The O-containing gas supply system primarily comprises gas supply pipe 232c, MFC 241c, and valve 243c. The F-containing gas supply system primarily comprises gas supply pipe 232d, MFC 241d, and valve 243d. The H-containing gas supply system primarily comprises gas supply pipe 232e, MFC 241e, and valve 243e. The inert gas supply system primarily comprises gas supply pipes 232f-232h, MFCs 241f-241h, and valves 243f-243h.

[0034] It should be noted that silane-based gases, O-containing gases, and H-containing gases are each or collectively referred to as film-forming gases (processing gases), and the silane-based gas supply system, O-containing gas supply system, and H-containing gas supply system are each or collectively referred to as film-forming gas supply systems (processing gas supply systems). Furthermore, the silane-based gas supply system is also referred to as a raw gas supply system, and the O-containing gas supply system and H-containing gas supply system are also referred to as oxidizing gas supply systems (oxidant supply systems). Furthermore, the N- and H-containing gas supply system and the F-containing gas supply system are each or collectively referred to as cleaning gas supply systems.

[0035] Any or all of the various gas supply systems described above may be configured as an integrated gas supply system 248, which is formed by integrating valves 243a-243h, MFCs 241a-241h, and the like. The integrated gas supply system 248 is connected to the gas supply pipes 232a-232h, respectively, and is configured so that the supply of various gases into the gas supply pipes 232a-232h, namely, the opening and closing of valves 243a-243h and the flow rate adjustment by MFCs 241a-241h, is controlled by a controller 121 (described later). The integrated gas supply system 248 is constructed as a single or split integrated unit, which can be attached to and detached from the gas supply pipes 232a-232h, etc., and can be maintained, replaced, or expanded.

[0036] An exhaust port 231a for exhausting the atmosphere in the processing chamber 201 is provided at the lower side wall of the reaction tube 203. Figure 2As shown, when viewed from above, the exhaust port 231a is positioned opposite (facing) the nozzles 249a to 249c (gas supply holes 250a to 250c) with the wafer 200 sandwiched therebetween. The exhaust port 231a can also be positioned 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 231a. 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 within the processing chamber 201, and an APC (Auto Pressure Controller) valve 244, serving as a pressure regulator (pressure regulation unit). The APC valve 244 is configured to open and close while the vacuum pump 246 is operating, thereby enabling vacuum evacuation and stopping of the processing chamber 201. Furthermore, the valve opening is adjusted based on pressure information detected by the pressure sensor 245 while the vacuum pump 246 is operating, thereby enabling pressure regulation within the processing chamber 201. The exhaust system primarily comprises the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may also be included in the exhaust system.

[0037] A sealing cover 219 is provided below the manifold 209 as a furnace port cover that can airtightly seal the lower end opening of the manifold 209. The sealing cover 219 is made of a metal material such as SUS and is formed into a disc shape. An O-ring 220b is provided on the upper surface of the sealing cover 219 as a sealing member that abuts the lower end of the manifold 209. A rotating mechanism 267 is provided below the sealing cover 219 to rotate the wafer boat 217 described later. The rotating shaft 255 of the rotating mechanism 267 is connected to the wafer boat 217 in a manner that passes through the sealing cover 219. The rotating mechanism 267 is configured to rotate the wafer 200 by rotating the wafer boat 217. The sealing cover 219 is configured to be raised and lowered in the vertical direction by the wafer boat elevator 115 as an elevating mechanism provided outside the reaction tube 203. The boat elevator 115 serves as a transport device (transport mechanism) that transports the wafers 200 into and out of the processing chamber 201 by raising and lowering the seal cap 219 .

[0038] A gate plate 219s, serving as a furnace port cover, is installed below the manifold 209. This gate plate 219s can airtightly seal the lower opening of the manifold 209 when the sealing cover 219 is lowered and the wafer boat 217 is removed from the processing chamber 201. The gate plate 219s is formed of a metal material, such as SUS, and is disc-shaped. An O-ring 220c, serving as a sealing member, is installed on the upper surface of the gate plate 219s, abutting against the lower end of the manifold 209. The opening and closing movements (lifting and rotating movements, etc.) of the gate plate 219s are controlled by the gate plate opening and closing mechanism 115s.

[0039] The wafer boat 217, serving as a substrate support, is configured to support multiple wafers 200, for example, 25 to 200, arranged vertically in a horizontal position with their centers aligned. The wafer boat 217 is made of a heat-resistant material such as quartz or SiC. Heat shields 218, also made of a heat-resistant material such as quartz or SiC, are supported in multiple stages at the bottom of the wafer boat 217.

[0040] A temperature sensor 263 is provided within the reaction tube 203 as a temperature detector. The power supply to the heater 207 is adjusted based on the temperature information detected by the temperature sensor 263, thereby achieving a desired temperature distribution within the processing chamber 201. The temperature sensor 263 is provided along the inner wall of the reaction tube 203.

[0041] like Figure 3 As shown, the controller 121, which serves as a control unit (control mechanism), is configured as a computer including a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, storage device 121c, and I / O port 121d are configured to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122, such as a touch panel, is connected to the controller 121.

[0042] The storage device 121c is composed of, for example, a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), etc. The storage device 121c stores, in a readable manner, a control program for controlling the operation of the substrate processing device, a process recipe that records the steps and conditions of the substrate processing described later, a cleaning recipe that records the steps and conditions of the cleaning processing described later, etc. The process recipe is obtained by combining the various steps of the substrate processing described later so that the controller 121 can execute and obtain a specified result, and functions as a program. The cleaning recipe is obtained by combining the various steps of the cleaning processing described later so that the controller 121 can execute and obtain a specified result, and functions as a program. Hereinafter, the process recipe, cleaning recipe, control recipe, etc. will also be referred to as a program. In addition, the process recipe and cleaning recipe will also be referred to as a process. In this specification, the term "program" may be used to include only the process, only the control recipe, or both the process and the control recipe. The RAM 121 b is configured as a memory area (work area) for temporarily storing programs, data, and the like read by the CPU 121 a .

[0043] The I / O port 121d is connected to the MFCs 241a to 241h, valves 243a to 243h, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotation mechanism 267, boat elevator 115, shutter opening and closing mechanism 115s, and the like.

[0044] 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. In accordance with the contents of the read recipe, the CPU 121a is configured to control the flow rate adjustment of various gases by the MFCs 241a to 241h, the opening and closing of the valves 243a to 243h, the opening and closing of the APC valve 244 and the pressure adjustment by the APC valve 244 using the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment of the heater 207 using the temperature sensor 263, the rotation and rotation speed adjustment of the wafer boat 217 by the rotation mechanism 267, the lifting and lowering of the wafer boat 217 by the boat elevator 115, and the opening and closing of the shutter 219s by the shutter opening and closing mechanism 115s.

[0045] The controller 121 can be constructed by installing the above-mentioned program 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, an optical disk such as an MO, a semiconductor memory such as a USB memory, an SSD, etc. The storage device 121c and the external storage device 123 are constructed in the form of a computer-readable recording medium. Hereinafter, they will also be referred to as recording media. In this specification, the term recording medium is used in cases where only the storage device 121c is included, only the external storage device 123 is included, or both the storage device 121c and the external storage device 123 are included. It should be noted that the provision of the program to the computer can also be carried out without using the external storage device 123, but using a communication mechanism such as the Internet or a dedicated line.

[0046] (2) Substrate processing

[0047] Main Use Figure 4 The following sequence example will be described: a sequence example in which a wafer 200 serving as a substrate is processed as one step in the semiconductor device manufacturing process using the substrate processing apparatus described above, that is, a film formation sequence example in which a film is formed on the wafer 200. In the following description, the operations of the various components constituting the substrate processing apparatus are controlled by the controller 121.

[0048] In the film formation sequence of this embodiment, a silicon oxide film (SiO film) is formed on the surface of the wafer 200 as a film containing Si and O by performing a cycle of the following steps non-simultaneously a predetermined number of times (n times, where n is an integer greater than or equal to 1):

[0049] Step 1 of supplying chlorosilane-based gas as a raw material gas to the wafer 200 in the processing chamber 201;

[0050] Step 2 of purging the process chamber 201 to remove residual gas from the process chamber 201;

[0051] Step 3 of supplying an O-containing gas and an H-containing gas as oxidizing gases to the wafer 200 in the processing chamber 201; and

[0052] Step 4: purging the process chamber 201 to remove residual gas from the process chamber 201.

[0053] In this specification, for convenience, the film formation sequence may be described as follows. The same description is also used in the following description of modifications and other aspects.

[0054]

[0055] In this specification, the term "wafer" may be used to refer to the wafer itself or to refer to a laminate of a wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of the wafer" may be used to refer to the surface of the wafer itself or to refer to the surface of a predetermined layer, etc., formed on the wafer. In this specification, the phrase "a predetermined layer is formed on the wafer" may refer to forming the predetermined layer directly on the surface of the wafer itself or to forming the predetermined layer on a layer, etc., formed on the wafer. In this specification, the term "substrate" has the same meaning as the term "wafer."

[0056] (Wafer filling and wafer boat loading)

[0057] After a plurality of wafers 200 are filled in the wafer boat 217 (wafer filling), the shutter 219s is moved by the shutter opening and closing mechanism 115s, and the lower end opening of the manifold 209 is opened (shutter opening). Figure 1 As shown, the boat 217 supporting a plurality of wafers 200 is lifted by the boat elevator 115 and carried into the processing chamber 201 (boat loading). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0058] (Pressure regulation and temperature regulation)

[0059] After the wafer boat is loaded, vacuum pump 246 performs vacuum evacuation (decompression evacuation) to reduce the pressure (vacuum level) within processing chamber 201, i.e., the space where wafers 200 are located. The pressure within processing chamber 201 is measured by pressure sensor 245, and feedback control (pressure regulation) is performed on APC valve 244 based on this measured pressure information. Heater 207 heats wafers 200 within processing chamber 201 to the desired processing temperature. Feedback control of heater 207 is performed based on temperature information detected by temperature sensor 263 to achieve the desired temperature distribution within processing chamber 201 (temperature regulation). Rotation of wafers 200 by rotation mechanism 267 is also initiated. Exhausting processing chamber 201, heating wafers 200, and rotating them continue at least until processing of wafers 200 is completed.

[0060] (Film Formation)

[0061] Then, execute the following steps 1 to 4 in sequence.

[0062] [Step 1]

[0063] In this step, chlorosilane-based gas is supplied to the wafer 200 in the processing chamber 201 .

[0064] Specifically, valve 243a is opened to allow chlorosilane gas to flow into gas supply pipe 232a. The chlorosilane gas is flow-regulated by MFC 241a, supplied into processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this point, chlorosilane gas is supplied to wafer 200 (chlorosilane gas supply). Alternatively, valves 243f through 243h may be opened to supply inert gas into processing chamber 201 via nozzles 249a through 249c, respectively.

[0065] The treatment conditions in this step can be exemplified as follows:

[0066] Chlorosilane gas supply flow rate: 0.005 to 2 slm, preferably 0.05 to 1 slm

[0067] Chlorosilane gas supply time: 1 to 120 seconds, preferably 1 to 60 seconds

[0068] Processing temperature: 250-800°C, preferably 400-700°C

[0069] Treatment pressure: 1-2666 Pa, preferably 67-1333 Pa.

[0070] It should be noted that in this specification, the expression of a numerical range such as "1 to 2666 Pa" means that the lower limit and the upper limit are included in the range. Thus, for example, "1 to 2666 Pa" means "1 Pa or more and 2666 Pa or less." The same applies to other numerical ranges.

[0071] By supplying chlorosilane gas to wafer 200 under the above conditions, a Si-containing layer (first layer) containing Cl is formed on the outermost surface of wafer 200, which serves as a substrate. The Si-containing layer containing Cl is formed by physical adsorption or chemical adsorption of chlorosilane gas molecules on the outermost surface of wafer 200, chemical adsorption of molecules of a substance obtained by partial decomposition of the chlorosilane gas, or accumulation of Si caused by thermal decomposition of the chlorosilane gas. The Si-containing layer containing Cl can be an adsorbed layer (physical adsorption layer, chemical adsorption layer) of molecules of chlorosilane gas or molecules of a substance obtained by partial decomposition of the chlorosilane gas, or a deposited layer of Si containing Cl. In this specification, the Si-containing layer containing Cl is simply referred to as the Si-containing layer.

[0072] Examples of chlorosilane gases that can be used include monochlorosilane (SiH3Cl, abbreviated as MCS) gas, dichlorosilane (SiH2Cl2, abbreviated as DCS) gas, trichlorosilane (SiHCl3, abbreviated as TCS) gas, tetrachlorosilane (SiCl4, abbreviated as STC) gas, hexachlorodisilane (Si2Cl6, abbreviated as HCDS) gas, and octachlorotrisilane (Si3Cl8, abbreviated as OCTS) gas. Fluorosilane gases such as silicon tetrafluoride (SiF4), bromosilane gases such as silicon tetrabromide (SiBr4), and iodosilane gases such as silicon tetraiodide (SiI4) can also be used in place of chlorosilane gases. In addition, aminosilane gases such as tetrakis(dimethylamino)silane (Si[N(CH3)2]4, abbreviated as: 4DMAS) gas, tris(dimethylamino)silane (Si[N(CH3)2]3H, abbreviated as: 3DMAS) gas, bis(diethylamino)silane (Si[N(C2H5)2]2H2, abbreviated as: BDEAS) gas, bis(tert-butylamino)silane (SiH2[NH(C4H9)]2, abbreviated as: BTBAS) gas, and (diisopropylamino)silane (SiH3[N(C3H7)2], abbreviated as: DIPAS) gas can be used instead of chlorosilane gases.

[0073] As the inert gas, a rare gas such as nitrogen (N 2 ) gas, argon (Ar) gas, helium (He) gas, neon (Ne) gas, or xenon (Xe) gas can be used. This also applies to the steps described below.

[0074] [Step 2]

[0075] After the Si-containing layer is formed on the wafer 200, the valve 243a is closed to stop the supply of the chlorosilane gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any remaining gas from the processing chamber 201. At this time, the valves 243f to 243h may be opened to supply an inert gas as a purge gas into the processing chamber 201, thereby purging the processing chamber 201 with the inert gas.

[0076] The treatment conditions in this step can be exemplified as follows:

[0077] Inert gas supply flow rate: 0.1~20slm

[0078] Inert gas supply time: 1 to 120 seconds, preferably 1 to 60 seconds.

[0079] The other treatment conditions are the same as those in step 1.

[0080] [Step 3]

[0081] After the purge in the processing chamber 201 is completed, an O-containing gas and a H-containing gas are supplied to the wafer 200 in the processing chamber 201 , that is, to the Si-containing layer formed on the wafer 200 .

[0082] Specifically, valves 243c and 243e are opened to allow O-containing gas and H-containing gas to flow into gas supply pipes 232c and 232e, respectively. The O-containing gas and H-containing gas are flow-regulated by MFCs 241c and 241e, respectively, and supplied into processing chamber 201 through nozzles 249c and 249b, and exhausted through exhaust port 231a. At this time, O-containing gas and H-containing gas are simultaneously supplied to wafer 200 (O-containing gas and H-containing gas supply). Alternatively, valves 243f to 243h may be opened to supply inert gas into processing chamber 201 through nozzles 249a to 249c, respectively.

[0083] The treatment conditions in this step can be exemplified as follows:

[0084] O-containing gas supply flow rate: 0.1~10slm

[0085] H-containing gas supply flow rate: 0.1~10slm

[0086] Each gas supply time: 1 to 120 seconds, preferably 1 to 60 seconds

[0087] Treatment pressure: 13.3-1333 Pa, preferably 13.3-399 Pa.

[0088] Other treatment conditions are the same as those in step 1.

[0089] By simultaneously and concurrently supplying an O-containing gas and an H-containing gas into the processing chamber 201, these gases are thermally activated (excited) and react in a heated, reduced-pressure atmosphere and a non-plasma atmosphere, thereby generating oxidizing species such as atomic oxygen (O) that contain oxygen but do not contain water (H2O). Furthermore, the Si-containing layer formed on the wafer 200 in step 1 is oxidized mainly using the oxidizing species. The energy possessed by the oxidizing species is higher than the bond energy of the Si-Cl bond and the like contained in the Si-containing layer. Therefore, by imparting the energy of the oxidizing species to the Si-containing layer, the Si-Cl bond and the like contained in the Si-containing layer are cut. The Cl and the like whose bonds to Si are cut are removed from the layer and discharged in the form of Cl2, HCl, etc. In addition, the bonding sites of Si remaining after the bonds to Cl and the like are cut combine with the O contained in the oxidizing species to form Si-O bonds. Thus, the Si-containing layer is converted (modified) into a layer containing Si and O with a low content of impurities such as Cl, that is, a high-purity SiO layer (second layer). This oxidation treatment can significantly improve the oxidizing power compared to the case where the O-containing gas is supplied alone or the case where HO gas (water vapor) is supplied alone. Specifically, by adding the H-containing gas to the O-containing gas under a reduced pressure atmosphere, a significant improvement in oxidizing power can be achieved compared to the case where the O-containing gas is supplied alone or the case where HO gas is supplied alone.

[0090] As the O-containing gas, oxygen (O2) gas, nitrous oxide (N2O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, ozone (O3) gas, H2O gas, carbon monoxide (CO) gas, carbon dioxide (CO2) gas, etc. can be used.

[0091] As the H-containing gas, hydrogen (H 2 ) gas, deuterium (D 2 ) gas, or the like can be used.

[0092] It should be noted that in step 1, when aminosilane gas is used instead of chlorosilane gas, in this step (step 3), instead of supplying H-containing gas, an oxidizing gas (oxidant) such as O3 gas may be supplied alone as the O-containing gas.

[0093] [Step 4]

[0094] After the Si-containing layer formed on the wafer 200 is converted into a SiO layer, the valves 243c and 243e are closed to stop the supply of the O-containing gas and the H-containing gas into the processing chamber 201, respectively. Then, the gas remaining in the processing chamber 201 is removed from the processing chamber 201 by the same processing steps and processing conditions as in step 2, and the processing chamber 201 is purged with an inert gas.

[0095] [Number of times of implementation]

[0096] By performing the above-described steps 1 to 4 non-simultaneously, i.e., asynchronously, a predetermined number of times (n times, where n is an integer greater than or equal to 1), a SiO film having a desired film thickness can be formed on the wafer 200. Preferably, the above-described cycle is repeated a plurality of times. Specifically, the thickness of the SiO layer formed in each cycle is preferably less than the desired film thickness, and the above-described cycle is repeated a plurality of times so that the film thickness of the SiO film formed by stacking the SiO layers reaches the desired film thickness.

[0097] (Post-purge and atmospheric pressure recovery)

[0098] After film formation is completed, inert gas is supplied into the processing chamber 201 from the nozzles 249a to 249c and exhausted from the exhaust port 231a. This purges the processing chamber 201, removing any remaining gas, byproducts, etc. (post-purge). The atmosphere in the processing chamber 201 is then replaced with the inert gas (inert gas replacement), and the pressure in the processing chamber 201 is restored to normal pressure (return to atmospheric pressure).

[0099] (Wafer boat unloading and wafer removal)

[0100] The boat elevator 115 then lowers the sealing cap 219, opening the lower end of the manifold 209. The processed wafers 200, supported by the boat 217, are then unloaded from the lower end of the manifold 209 to the exterior of the reaction tube 203 (boat unloading). After the boat is unloaded, the shutter 219s is moved, sealing the lower end of the manifold 209 with the shutter 219s via the O-ring 220c (shutter closing). After being unloaded to the exterior of the reaction tube 203, the processed wafers 200 are removed from the boat 217 (wafer removal).

[0101] (3) Cleaning

[0102] During the above-mentioned substrate processing, i.e., processing of the wafer 200, substances containing Si and O, such as deposits containing silicon oxides such as SiO films, adhere to the surfaces of components in the processing container, such as the inner wall surface of the reaction tube 203, the surface of the wafer boat 217, etc. Therefore, using the above-mentioned substrate processing apparatus, after the above-mentioned processing of the wafer 200 is performed a predetermined number of times (one or more) as a step in the manufacturing process of the semiconductor device, a cleaning process is performed to remove the substances containing Si and O (hereinafter referred to as attached substances) adhered to the processing container. Hereinafter, the main method used is Figure 5 A description will be given of an example sequence for cleaning the interior of the processing container after processing the wafer 200. In the following description, the operations of the various components constituting the substrate processing apparatus are also controlled by the controller 121.

[0103] In the cleaning sequence of this method, a cycle including the following step a and the following step b is performed at a first temperature a predetermined number of times (m times, where m is an integer greater than or equal to 1), thereby performing a step (etching) of removing substances adhered to the processing container:

[0104] Step a, wherein one of a gas containing N and H and a gas containing F is supplied into a processing container after the wafer 200 is processed; and

[0105] Step b is to supply another gas different from the one gas, one of the N and H containing gas and the F containing gas, into the processing container in a state where the one gas remains.

[0106] In this embodiment, as an example, a case where a gas containing N and H is supplied as one gas in step a and a gas containing F is supplied as another gas in step b is described.

[0107] In addition, this method describes, as an example, a case where, in step a, the processing container is filled with N- and H-containing gases, and, in step b, the F-containing gas is mixed with the N- and H-containing gases filling the processing container. In addition, in step b, this method describes, as an example, a case where, after stopping the supply of N- and H-containing gases into the processing container, the supply of the F-containing gas into the processing container is started. In addition, in step b, this method describes, as an example, a case where, in step b, the following steps b1 and b2 are performed: step b1, in which the F-containing gas is supplied into the processing container while exhausting the processing container is stopped; and step b2, in which the F-containing gas is supplied into the processing container while exhausting the processing container is performed.

[0108] In this embodiment, as an example, a case where a gas containing N and H is supplied into the processing container while the processing container is being exhausted in step a will be described.

[0109] In addition, this embodiment will describe, as an example, a case where the above cycle further includes step c: exhausting the processing container while stopping the supply of the N- and H-containing gas and the F-containing gas into the processing container. In addition, this embodiment will describe, as an example, a case where an inert gas is supplied into the processing chamber 201 to purge the processing chamber 201 with the inert gas in step c.

[0110] In addition, in this method, as an example, the case where the following step d (sublimation) is also performed is described: in this step d, after the above-mentioned etching is performed, the inside of the processing container is heated and exhausted at a second temperature higher than the first temperature, so that the by-products generated during the above-mentioned etching and the by-products remaining in the processing container after the above-mentioned etching are sublimated.

[0111] In this specification, for convenience, the cleaning sequence may be described as follows. The same description is also used in the following modifications and other embodiments.

[0112] (Gas containing N and H → Gas containing F → Purge) × m → Sublimation

[0113] (Crystal boat loading)

[0114] The shutter 219s is moved by the shutter opening and closing mechanism 115s, thereby opening the lower end of the manifold 209 (the shutter is open). Subsequently, the empty wafer boat 217, whose surface is covered with a substance containing Si and O, i.e., the wafer boat 217 without wafers 200, is lifted by the boat elevator 115 and loaded into the processing container containing a substance containing Si and O, i.e., the processing chamber 201. In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0115] (Pressure regulation and temperature regulation)

[0116] After the wafer boat is loaded, vacuum exhaust (decompression exhaust) is performed by the vacuum pump 246 to achieve the desired pressure (vacuum degree) in the processing chamber 201. At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback controlled (pressure regulated) based on the measured pressure information. In addition, heating is performed by the heater 207 to achieve the desired processing temperature in the processing chamber 201. At this time, the power supply status of the heater 207 is feedback controlled based on the temperature information detected by the temperature sensor 263 to achieve the desired temperature distribution (temperature regulation) in the processing chamber 201. In addition, the rotation of the wafer boat 217 by the rotation mechanism 267 is started. The operation of the vacuum pump 246, the heating in the processing chamber 201, and the rotation of the wafer boat 217 are all continued at least until the cleaning process is completed. It should be noted that the wafer boat 217 does not have to rotate.

[0117] (Etching)

[0118] After that, execute the following steps a to c in sequence.

[0119] [Step a]

[0120] In step a, a gas containing N and H is supplied into the processing chamber 201 while the processing chamber 201 is exhausted.

[0121] Specifically, while APC valve 244 is open and the process chamber 201 is being evacuated, valve 243b is opened to allow the N- and H-containing gas to flow into gas supply pipe 232b. The N- and H-containing gas is flow-regulated by MFC 241b, supplied into the process chamber 201 through nozzle 249b, and exhausted from exhaust port 231a (N- and H-containing gas supply). At this time, valves 243f to 243h may also be opened to supply inert gas into the process chamber 201 through nozzles 249a to 249c, respectively.

[0122] The treatment conditions in this step can be exemplified as follows:

[0123] N and H containing gas supply flow rate: 0.1 to 20 slm, preferably 1 to 10 slm

[0124] Inert gas supply flow rate: 0 to 50 slm, preferably 0 to 10 slm

[0125] Each gas supply time: 1 second to 60 minutes, preferably 10 seconds to 30 minutes

[0126] Treatment pressure (first pressure): 1 to 39900 Pa, preferably 1 to 13300 Pa

[0127] Treatment temperature (first temperature): 20 to 400°C, preferably 50 to 150°C.

[0128] It should be noted that Figure 5 The pressure and temperature shown are respectively set pressure and set temperature for the purpose of simplicity, that is, the pressure and temperature of the target value of the control. The actual pressure and temperature in the processing chamber 201 are not limited to Figure 5 In the case of fixed values ​​shown, each may change over time to reach the target value.

[0129] By performing this step under the aforementioned process steps and process conditions, the process chamber 201 is filled with the N and H containing gas, and the N and H containing gas can be dispersed throughout the entire range of the process chamber 201 .

[0130] After a predetermined time has passed, the supply of the N and H containing gas into the processing chamber 201 is stopped.

[0131] As the gas containing N and H, a hydrogen nitride-based gas such as ammonia (NH 3 ) gas, diazene (N 2 H 2 ) gas, hydrazine (N 2 H 4 ) gas, or N 3 H 8 gas can be used.

[0132] [Step b1]

[0133] After step a is completed, the exhaust in the processing chamber 201 is stopped, and then the F-containing gas is supplied into the processing chamber 201 where the N- and H-containing gases remain.

[0134] Specifically, APC valve 244 is fully closed (fully closed) to stop exhaust within process chamber 201. Then, valve 243d is opened to allow the F-containing gas to flow into gas supply pipe 232d. The F-containing gas is flow-regulated by MFC 241d and supplied into process chamber 201 via nozzle 249a (F-containing gas supply). At this point, valves 243f to 243h may be opened to supply inert gas into process chamber 201 via nozzles 249a to 249c, respectively.

[0135] The treatment conditions in this step can be exemplified as follows:

[0136] F-containing gas supply flow rate: 0.1-10 slm, preferably 1-3 slm

[0137] Inert gas supply flow rate: 0 to 50 slm, preferably 0 to 10 slm

[0138] Each gas supply time: 1 second to 60 minutes, preferably 10 seconds to 10 minutes

[0139] Treatment pressure (second pressure): a pressure higher than the first pressure, for example, 5 to 39,900 Pa, preferably 5 to 26,600 Pa.

[0140] The other treatment conditions are the same as those in step a.

[0141] By performing this step under the aforementioned processing steps and processing conditions, the F-containing gas can be mixed with the N- and H-containing gas filling the processing chamber 201 by performing step a. Furthermore, the pressure within the processing chamber 201 can be raised to a second pressure higher than the first pressure. This allows the mixture of the N- and H-containing gas and the F-containing gas to react with attached substances within the processing chamber 201, thereby etching the attached substances. It should be noted that as etching proceeds, H2O and other H- and O-containing substances may be generated within the processing chamber 201 through the reaction between the mixture of the N- and H-containing gas and the F-containing gas and the attached substances within the processing chamber 201. These H2O and other H- and O-containing substances have the effect of promoting the etching reaction. Furthermore, as etching proceeds, gaseous byproducts such as silicon tetrafluoride (SiF4), hexafluorosilicic acid (H2SiF6), and ammonium hexafluorosilicate ((NH4)2SiF6) may be generated within the processing chamber 201. These byproducts may reduce the etching efficiency of attached substances within the processing chamber 201.

[0142] As the F-containing gas, fluorine (F 2 ) gas, chlorine trifluoride (ClF 3 ) gas, chlorine monofluoride (ClF) gas, nitrogen trifluoride (NF 3 ) gas, hydrogen fluoride (HF) gas, or the like can be used.

[0143] [Step b2]

[0144] After step b1 is completed and the process chamber 201 is exhausted, the F-containing gas is supplied into the process chamber 201 in which a mixed gas of the N- and H-containing gas and the F-containing gas and gaseous by-products remain.

[0145] Specifically, APC valve 244 is opened to a predetermined opening to initiate exhaust of the process chamber 201. Furthermore, valve 243d is maintained open to continuously supply F-containing gas into gas supply pipe 232d. The F-containing gas is continuously supplied into the process chamber 201 through nozzle 249a, with its flow rate regulated by MFC 241d. It is then exhausted from exhaust port 231a along with various gases and gaseous byproducts that fill the process chamber 201 (F-containing gas supply). At this point, valves 243f to 243h may also be opened to supply inert gas into the process chamber 201 through nozzles 249a to 249c, respectively.

[0146] The treatment conditions in this step can be exemplified as follows:

[0147] Each gas supply time: 1 second to 5 minutes, preferably 10 seconds to 1 minute

[0148] Treatment pressure (third pressure): a pressure equal to or higher than the second pressure, for example, 10 to 39,900 Pa, preferably 10 to 26,600 Pa.

[0149] The other treatment conditions are the same as those in step a.

[0150] By performing this step under the aforementioned processing steps and conditions, the reaction between the mixed gas containing N and H and the F-containing gas and the attached substances in the processing chamber 201 can be further promoted, thereby further etching the attached substances. In addition, gaseous byproducts generated as the etching of the attached substances proceeds can be exhausted (removed) from the processing chamber 201.

[0151] After a predetermined time has passed, the valve 243 d is closed to stop the supply of the F-containing gas into the processing chamber 201 .

[0152] [Step c]

[0153] After step b2 is completed, the processing chamber 201 is exhausted while the supply of the N- and H-containing gas and the F-containing gas into the processing chamber 201 is stopped, and an inert gas is further supplied into the processing chamber 201 .

[0154] Specifically, APC valve 244 is fully opened to continuously exhaust the process chamber 201. Valves 243f to 243h are then opened to allow inert gas to flow into gas supply pipes 232f to 231h as a purge gas. The inert gas is flow-regulated by MFCs 241f to 241h and supplied into the process chamber 201 through nozzles 249a to 249c. The inert gas is then exhausted from exhaust port 231a along with various gases and gaseous byproducts remaining in the process chamber 201 (purge gas supply).

[0155] The treatment conditions in this step can be exemplified as follows:

[0156] Inert gas supply flow rate: 0.1 to 50 slm, preferably 1 to 20 slm

[0157] Gas supply time: 1 second to 30 minutes, preferably 5 seconds to 5 minutes

[0158] Treatment pressure (fourth pressure): a pressure lower than the third pressure, preferably lower than the second pressure, and further preferably lower than the first pressure, and is, for example, 0.1 to 26,600 Pa, preferably 0.1 to 13,300 Pa.

[0159] The other treatment conditions are the same as those in step a.

[0160] By performing this step under the above-described processing steps and processing conditions, N- and H-containing gases, F-containing gases remaining in the processing chamber 201 , and gaseous byproducts generated during etching of attached substances can be removed from the processing chamber 201 .

[0161] [Number of times of implementation]

[0162] By performing the above steps a to c non-simultaneously, i.e., a cycle of steps a, b1, b2, and c a predetermined number of times (m times, where m is an integer greater than or equal to 1), the attached substances in the processing chamber 201 can be removed.

[0163] (sublimation)

[0164] As described above, by performing the cycle including step b2 and step c a predetermined number of times, at least a portion of the gaseous byproducts generated as the etching proceeds is removed from the processing chamber 201. However, there are cases where a portion of these gaseous byproducts adheres to and solidifies on the surfaces of components within the processing chamber 201, thereby remaining within the processing chamber 201. Therefore, in order to remove the solid byproducts (e.g., fluorides such as SiF4) remaining within the processing chamber 201, after the etching is completed, the processing chamber 201 is heated at a second temperature that is higher than the first temperature to sublime the byproducts.

[0165] Specifically, the output of the heater 207 is adjusted so that the temperature in the processing chamber 201 is changed to a temperature higher than the temperature in the processing chamber 201 during etching (the first temperature). In addition, the APC valve 244 is fully opened to exhaust the processing chamber 201. At this time, the valves 243f to 243h can also be opened to allow inert gas to flow into the gas supply pipes 232f to 231h as a purge gas. The inert gas is flow-regulated by the MFCs 241f to 241h and supplied to the processing chamber 201 through the nozzles 249a to 249c. It is then exhausted from the exhaust port 231a together with the by-products that have become gaseous by sublimation (purge gas supply).

[0166] The treatment conditions in this step can be exemplified as follows:

[0167] Inert gas supply time: 1 second to 300 minutes, preferably 5 to 60 minutes

[0168] Treatment pressure (fifth pressure): a pressure lower than the third pressure, preferably lower than the second pressure, and more preferably lower than the first pressure, and is, for example, 0.1 to 26600 Pa, preferably 0.1 to 13300 Pa

[0169] Treatment temperature (second temperature): a temperature equal to or higher than the first temperature, preferably a temperature higher than the first temperature, for example, 100 to 800°C, preferably 300 to 500°C.

[0170] By performing this step under the above-described processing steps and processing conditions, byproducts remaining in the processing chamber 201 after being adsorbed and solidified on the surfaces of components in the processing chamber 201 can be sublimated and removed from the processing chamber 201 .

[0171] (Post-purge and atmospheric pressure recovery)

[0172] After sublimation is complete, inert gas is supplied into the processing chamber 201 from nozzles 249a-249c, and exhausted from exhaust port 231a. This purges the processing chamber 201, removing any remaining gas, byproducts, etc. (post-purge) from the processing chamber 201 after sublimation. The atmosphere in the processing chamber 201 is then replaced with the inert gas (inert gas replacement), and the pressure in the processing chamber 201 is restored to normal pressure (return to atmospheric pressure).

[0173] (Unloading of crystal boat)

[0174] Afterwards, the sealing cap 219 is lowered by the boat elevator 115, and the lower end of the manifold 209 is opened (the boat is unloaded). After the boat is unloaded, 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 (the shutter is closed). Then, the substrate processing described above is resumed.

[0175] (4) Effects of this method

[0176] According to this aspect, one or more of the following effects can be obtained.

[0177] (a) By performing a cycle comprising the following steps a and b at a first temperature a predetermined number of times, it is possible to more efficiently etch attached material within the processing container, compared to the case where a F-containing gas is supplied solely into the processing container: in step a, a gas containing N and H is supplied into the processing container after processing the wafer 200; in step b, a F-containing gas is supplied into the processing container in a state where N and H-containing gases remain. This shortens the cleaning time within the processing container, reduces the downtime of the substrate processing apparatus, and improves the productivity of substrate processing. Furthermore, by adjusting the number of cycles, etc., it is possible to improve the controllability of the amount of attached material removed (etching amount). Furthermore, by improving etching efficiency, it is possible to reduce the amount of cleaning gas used to etch attached material within the processing container.

[0178] (b) By filling the processing container with N2 and H2-containing gases in step a and then mixing the F2-containing gas with the N2 and H2-containing gases in step b, it is possible to efficiently etch away adhering materials within the processing container, shortening the cleaning time. Furthermore, the entire processing container, including corners, can be cleaned uniformly.

[0179] (c) In step b, by starting to supply F-containing gas into the processing container after stopping the supply of N- and H-containing gases into the processing container, the controllability of the etching amount of the attached material in the processing container can be improved compared to the case where the supply of N- and H-containing gases and the supply of F-containing gas into the processing container overlap.

[0180] (d) In step b1, by supplying the F-containing gas into the processing vessel while the exhaust within the processing vessel is stopped, the amount of cleaning gas used to etch adhering substances within the processing vessel can be reduced. Furthermore, the pressure within the processing vessel can be quickly increased, resulting in a shorter cleaning time. Furthermore, the entire processing vessel, including corners, can be cleaned uniformly.

[0181] (e) In step b2, by supplying F-containing gas into the processing container while exhausting the processing container, gaseous by-products generated during the etching of the attached substances can be removed from the processing container, thereby suppressing the reduction in etching efficiency of the attached substances caused by the influence of the by-products.

[0182] (f) In step a, by supplying a gas containing N and H into the processing container while exhausting the processing container, the interior of the processing container can be cleaned using the gas containing N and H. Furthermore, depending on the processing conditions in step a, at least a portion of the adhering material in the processing container may be nitrided. As a result, the adhering material can be efficiently etched.

[0183] (g) In step c, by exhausting the processing container while stopping the supply of N- and H-containing gases and F-containing gases into the processing container, gaseous by-products generated as a result of the etching of the attached substances in the processing container can be removed from the processing container, thereby suppressing the reduction in etching efficiency of the attached substances caused by the influence of the by-products.

[0184] (h) After etching, step (d) of heating the interior of the processing container at a second temperature that is higher than the first temperature allows byproducts remaining in the processing container to sublime. This facilitates removal of byproducts from the processing container, thereby suppressing a decrease in etching efficiency of attached substances caused by the byproducts.

[0185] Note that, in step d, by setting the temperature in the processing container to a second temperature higher than the first temperature, the effects described here can be further enhanced.

[0186] Furthermore, in step d, by purging the interior of the processing container with an inert gas, the sublimated by-products can be efficiently removed from the processing container, further enhancing the effects described herein.

[0187] (i) By setting the processing pressure in step a to a first pressure, setting the processing pressure in step b1 to a second pressure higher than the first pressure, and setting the processing pressure in step b2 to a third pressure greater than the second pressure, the etching efficiency of attached substances can be improved. Furthermore, by setting the processing pressure in step b2 to a third pressure greater than the second pressure, the re-adhesion of etched attached substances within the processing container can be suppressed. Consequently, cleaning time can be shortened.

[0188] (j) By setting the first to third pressures in accordance with the various methods described above, the processing pressure in step c is set to a fourth pressure that is lower than the third pressure, thereby improving the etching efficiency of the attached substances. That is, the removal efficiency of the gaseous byproducts generated in conjunction with the etching of the attached substances from the processing container can be improved, and the adhesion of the substances to the processing container can be suppressed, thereby maintaining a high etching efficiency of the attached substances. As a result, the cleaning time can be shortened. It should be noted that by making the fourth pressure lower than the third pressure, the effect described here can be fully obtained. In addition, by making the fourth pressure lower than the second pressure, the effect described here can be further improved. In addition, by making the fourth pressure lower than the first pressure, the effect described here can be further improved.

[0189] (k) By setting the first to fourth pressures in accordance with the various methods described above, the processing pressure in step d is set to a fifth pressure that is lower than the third pressure, thereby improving the etching efficiency of the attached substances. That is, the removal efficiency of the gaseous byproducts generated in conjunction with the etching of the attached substances from the processing container can be improved, and the adhesion of the substances to the processing container can be suppressed, thereby maintaining a high etching efficiency of the attached substances. As a result, the cleaning time can be shortened. It should be noted that by making the fifth pressure lower than the third pressure, the effect described here can be fully obtained. In addition, by making the fifth pressure lower than the second pressure, the effect described here can be further improved. In addition, by making the fifth pressure lower than the first pressure, the effect described here can be further improved.

[0190] (1) By making the supply flow rate of the N and H containing gas in step a greater than the supply flow rate of the F containing gas in step b, the attached materials in the processing container can be etched efficiently, and the cleaning time can be shortened.

[0191] (m) By making the supply time of the N and H containing gas in step a longer than the supply time of the F containing gas in step b, it is possible to efficiently etch the attached substances in the processing container and shorten the cleaning time.

[0192] (n) During etching, by using a gas containing N and H as one gas and a gas containing F as the other gas, one or more of the above effects can be significantly achieved.

[0193] (o) During etching, by using at least one of NH3 gas, N2H2 gas, N2H4 gas and N3H8 gas as one gas and at least one of F2 gas, ClF3 gas, ClF gas, NF3 gas and HF gas as another gas, one or more of the above-mentioned effects can be more significantly obtained.

[0194] (p) During etching, by using NH₃ gas as one gas and HF gas as the other gas, one or more of the aforementioned effects can be significantly achieved. In particular, when HF gas is used as the other gas, water (H₂O) can be generated within the processing vessel during the etching reaction in steps b1 and b2, and this water can be used to promote the etching of adhering substances within the processing vessel. In this case, the first temperature is preferably a low temperature condition that makes it difficult for the generated water to be removed from the processing vessel.

[0195] (q) One or more of the above effects are particularly significantly achieved when the substance adhering to the processing container by processing the wafer 200 is a substance containing Si and O, such as silicon oxide (SiO film).

[0196] (r) Since this method of etching is performed in a non-plasma atmosphere, the controllability of the amount of etching of adhering materials in the processing container can be improved. In addition, since this method of sublimation is performed in a non-plasma atmosphere, plasma damage to components in the processing container can also be avoided.

[0197] (s) The above-mentioned effects can also be obtained by using the above-mentioned various silane gases, the above-mentioned O-containing gases, and the above-mentioned H-containing gases in substrate processing, by using the above-mentioned N- and H-containing gases and the above-mentioned F-containing gases in cleaning processing, and by using the above-mentioned various inert gases in the above-mentioned processes.

[0198] (5) Modification

[0199] The cleaning process sequence of this method can be changed according to the following modified examples. These modified examples can be combined arbitrarily. Unless otherwise specified, the processing steps and processing conditions in each step of each modified example can be the same as the processing steps and processing conditions in each step of the above-mentioned cleaning process.

[0200] (Variation 1)

[0201] As shown in the cleaning sequence described below, in step a, the F-containing gas may be supplied as one of the N- and H-containing gas and the F-containing gas, and in step b, the N- and H-containing gas may be supplied as the other gas of the N- and H-containing gas and the F-containing gas. In these cases, at least some of the effects described in the above embodiment can be achieved.

[0202] (F-containing gas → N and H-containing gas → purge) × m → sublimation

[0203] (Variation 2)

[0204] As shown in the cleaning sequence described below, step c may not be performed in each cycle. In these cases, at least part of the effects described in the above embodiment can be obtained.

[0205] (Gas containing N and H → Gas containing F) × m → Sublimation

[0206] (gas containing F → gas containing N and H) × m → sublimation

[0207] (Variation 3)

[0208] As shown in the cleaning sequence described below, the processing container can also be purged at regular intervals between step a and step b (step b1) in each cycle. The regular purging between steps a and b can be performed under the same processing steps and processing conditions as those in step c above. In these cases, at least part of the effects described in the above manner can also be obtained. It should be noted that in this modification, since the amount of the mixture of N- and H-containing gases and F-containing gases is reduced, the above reaction can be suppressed and etching can be performed in minute amounts. Therefore, this modification is particularly effective when the thickness of the attached material in the processing container is thin.

[0209] (Gas containing N and H → Purge → Gas containing F) × m → Sublimation

[0210] (F-containing gas → purge → N and H-containing gas) × m → sublimation

[0211] (Gas containing N and H → purge → Gas containing F → purge) × m → sublimation

[0212] (Gas containing F → purge → Gas containing N and H → purge) × m → sublimation

[0213] (Variation 4)

[0214] As shown in the cleaning sequence described below, etching and sublimation can also be repeated (hereinafter, m is an integer greater than 1, and p is an integer greater than 2). In this case, at least some of the effects described in the above embodiment can be achieved. It should be noted that this variation is particularly effective when the thickness of the attached material in the processing container is thick.

[0215] [(gas containing N and H → gas containing F → purge) × m → sublimation] × p

[0216] [(gas containing F → gas containing N and H → purge) × m → sublimation] × p

[0217] <Other aspects of the present invention>

[0218] While the embodiments of the present invention have been specifically described above, the present invention is not limited to the above embodiments and various modifications can be made without departing from the spirit and scope of the present invention.

[0219] While the above embodiment illustrates the cleaning process using an example in which sublimation is performed after etching, the present invention is not limited thereto. Sublimation, that is, step d, may not be performed. Even in this case, at least some of the effects described in the above embodiment can be achieved. In particular, according to the above embodiment, since step c is performed in each cycle, depending on the processing conditions in step c, byproducts generated during etching can be fully removed from the processing vessel in step c performed in each cycle, even without the additional step of sublimation.

[0220] In the above embodiment, the following example is used for description (but the present invention is not limited thereto): after supplying N and H containing gases in step a, in step b1, supplying F containing gas while stopping exhaust within the processing container, and in step b2, supplying F containing gas while exhausting the processing container. For example, after executing step a, step b1 may be omitted and step b2 may be executed instead. In this case, at least some of the effects described in the above embodiment can also be achieved.

[0221] While the above method uses the example of stopping the supply of N- and H-containing gases into the processing vessel in step b and then restarting the supply of F-containing gas into the processing vessel, the present invention is not limited to this. For example, the supply of N- and H-containing gases in step a may overlap at least partially with the supply of F-containing gas in step b. In this case, at least some of the effects described in the above method can also be achieved. It should be noted that in this case, the etching rate and etching efficiency can be further increased. Consequently, the cleaning time can also be further shortened.

[0222] In addition, the above-described embodiment describes an example in which a SiO film is formed on the wafer 200 during substrate processing. However, the present invention is not limited thereto. For example, the above-described cleaning process can also be preferably applied to the case in which a Si-based oxide film such as a silicon oxycarbide film (SiOC film), a silicon oxycarbonitride film (SiOCN film), or a silicon oxynitride film (SiON film) is formed on the wafer 200 during substrate processing. Furthermore, the above-described cleaning process can also be preferably applied to the case in which a metal oxide film such as a titanium oxide film (TiO film), an aluminum oxide film (AlO film), a hafnium oxide film (HfO film), or a zirconium oxide film (ZrO film) is formed on the wafer 200. In these cases, at least some of the effects described in the above-described embodiment can also be achieved.

[0223] The recipe used in each process is preferably prepared individually according to the process content and stored in advance in the storage device 121c via an electrical communication line or the external storage device 123. Furthermore, when each process is started, the CPU 121a preferably selects an appropriate recipe from the multiple recipes stored in the storage device 121c according to the process content. This allows for the formation of films of various film types, composition ratios, film qualities, and film thicknesses with high reproducibility using a single substrate processing apparatus. Furthermore, each process can be started quickly while reducing the burden on the operator and preventing operational errors.

[0224] The above-described process is not limited to newly prepared processes; for example, it can also be prepared by modifying an existing process already installed in a substrate processing apparatus. When modifying a process, the modified process can be installed in the substrate processing apparatus via an electrical communication line or a recording medium containing the modified process. Alternatively, the existing process installed in the substrate processing apparatus can be modified directly by operating the input / output device 122 of the existing substrate processing apparatus.

[0225] The above-described embodiment describes an example of film formation using a batch-type substrate processing apparatus that processes multiple substrates at a time. The present invention is not limited to the above-described embodiment; for example, it can also be preferably applied to film formation using a single-wafer-type substrate processing apparatus that processes one or several substrates at a time. Furthermore, the above-described embodiment describes an example of film formation using a substrate processing apparatus equipped with a hot-wall processing furnace. The present invention is not limited to the above-described embodiment; it can also be preferably applied to film formation using a substrate processing apparatus equipped with a cold-wall processing furnace.

[0226] When the above substrate processing apparatus is used, each process can be performed under the same processing steps and processing conditions as those in the above-mentioned embodiment, and the same effects as those in the above-mentioned embodiment can be obtained.

[0227] The above-mentioned methods can be used in combination as appropriate. The processing steps and processing conditions in this case can be, for example, the same as those in the above-mentioned methods.

[0228] Example

[0229] As an example, using Figure 1 The substrate processing apparatus shown forms a SiO film on a wafer within a processing container using the same processing steps and conditions as the substrate processing described above. Subsequently, adhering materials within the processing container are removed using the same processing steps and conditions as the cleaning process described above. It should be noted that in step a, NH3 gas is used as the N and H-containing gas, and in step b, HF gas is used as the F-containing gas.

[0230] As a comparative example, Figure 1 The substrate processing apparatus shown forms a SiO film on a wafer within a processing vessel using the same processing steps and conditions as those used in the aforementioned substrate processing method. These processing steps and conditions are identical to those used in the embodiment. Subsequently, HF gas is supplied separately to the processing vessel to remove adhering materials. The processing steps and conditions for supplying HF gas are identical to those used in step b1 of the embodiment.

[0231] Afterwards, the etching amount of the attached material in the processing container was measured for each of the embodiment and the comparative example. The result showed that the etching amount of the attached material in the comparative example was In contrast, the etching amount of the attached material in the embodiment is As described above, it was confirmed that the etching rate in the cleaning process of the example increased to 83 times or more the etching rate in the cleaning process of the comparative example.

Claims

1. A cleaning method for a process container, comprising the step of removing substances adhered to the process container by performing a cycle comprising the following steps at a first temperature a predetermined number of times: (a) supplying one of a nitrogen- and hydrogen-containing gas and a fluorine-containing gas into the processing container after the substrate has been processed; and (b) supplying another gas, different from the one gas, of the nitrogen- and hydrogen-containing gas and the fluorine-containing gas into the processing container in a state where the one gas remains, in, (b) having the following steps: (b1) supplying the other gas into the processing container while stopping exhaust in the processing container; and (b2) A step of supplying the other gas into the processing container while the processing container is being evacuated.

2. The cleaning method according to claim 1, wherein In (a), the processing container is filled with the one gas, In (b), the other gas is mixed with the one gas filled in the processing container.

3. The cleaning method according to claim 1, wherein: In (b), after the supply of the one gas into the processing container is stopped, the supply of the other gas into the processing container is started.

4. The cleaning method according to claim 1, wherein In (a), the one gas is supplied into the processing container while the processing container is being exhausted.

5. The cleaning method according to claim 1, wherein The cycle further includes (c) a step of exhausting the processing container while stopping the supply of the nitrogen- and hydrogen-containing gas and the fluorine-containing gas into the processing container. The cleaning method according to claim 1 , wherein: The method further includes the step of (d) heating the interior of the processing container at a second temperature and exhausting the interior of the processing container, wherein the second temperature is a temperature higher than the first temperature.

7. The cleaning method according to claim 1, wherein: The pressure in the processing container in (a) is set to a first pressure, (b1) setting the pressure in the processing container to a second pressure higher than the first pressure, The pressure in the processing container in (b2) is set to a third pressure that is equal to or higher than the second pressure.

8. The cleaning method according to claim 1, wherein: The cycle further includes (c) exhausting the processing container while stopping the supply of the nitrogen- and hydrogen-containing gas and the fluorine-containing gas into the processing container. The pressure in the processing container in (a) is set to a first pressure, (b1) setting the pressure in the processing container to a second pressure higher than the first pressure, (b2) setting the pressure in the processing container to a third pressure that is greater than the second pressure, The pressure in the processing container in (c) is set to a fourth pressure lower than the third pressure.

9. The cleaning method according to claim 1, wherein: The cycle further includes (c) exhausting the processing container while stopping the supply of the nitrogen- and hydrogen-containing gas and the fluorine-containing gas into the processing container. The cleaning method further comprises the step of (d) heating and exhausting the interior of the processing container at a second temperature, wherein the second temperature is a temperature higher than the first temperature. The pressure in the processing container in (a) is set to a first pressure, (b1) setting the pressure in the processing container to a second pressure higher than the first pressure, (b2) setting the pressure in the processing container to a third pressure that is greater than the second pressure, (c) setting the pressure in the processing container to a fourth pressure lower than the third pressure, The pressure in the processing container in (d) is set to a fifth pressure lower than the third pressure.

10. The cleaning method according to claim 1, wherein: The supply flow rate of the one gas in (a) is made larger than the supply flow rate of the other gas in (b).

11. The cleaning method according to claim 1, wherein: The supply time of the other gas in (b) is made longer than the supply time of the one gas in (a).

12. The cleaning method according to claim 1, wherein: By performing the cycle a predetermined number of times, at least a portion of the substance adhering to the processing container is removed, and a portion of the by-products generated during the process is removed.

13. The cleaning method according to claim 6, wherein: By performing the cycle a predetermined number of times, at least a portion of the substance adhering to the processing container is removed, and a portion of the by-products generated during the process is removed. In (d), the by-product remaining in the processing container is sublimated.

14. The cleaning method according to claim 1, wherein: The one gas is the nitrogen- and hydrogen-containing gas, and the other gas is the fluorine-containing gas.

15. The cleaning method according to claim 1, wherein The nitrogen and hydrogen-containing gas includes at least any one of NH3 gas, N2H2 gas, N2H4 gas and N3H8 gas. The fluorine-containing gas includes at least any one of F2 gas, ClF3 gas, ClF gas, NF3 gas, and HF gas.

16. The cleaning method according to claim 1, wherein: The nitrogen and hydrogen-containing gas includes NH 3 gas, and the fluorine-containing gas includes HF gas.

17. The cleaning method according to claim 1, wherein: The substance adhered to the inside of the processing container includes silicon and oxygen.

18. The cleaning method according to claim 6, wherein: The step of removing the substances adhering to the inside of the processing container and step (d) are repeated.

19. The cleaning method according to claim 1, wherein: The step of removing substances adhering to the inside of the processing container is performed in a non-plasma atmosphere.

20. A method for manufacturing a semiconductor device, comprising: supplying a processing gas to a substrate in a processing container to process the substrate; and a step of cleaning the inside of the processing container after processing the substrate; The step of cleaning the interior of the processing container includes the step of removing substances adhered to the processing container by performing a cycle including the following steps at a first temperature for a predetermined number of times: (a) supplying one of a nitrogen- and hydrogen-containing gas and a fluorine-containing gas into the processing container after the substrate has been processed; and (b) supplying another gas, different from the one gas, of the nitrogen- and hydrogen-containing gas and the fluorine-containing gas into the processing container in a state where the one gas remains, in, (b) having the following steps: (b1) supplying the other gas into the processing container while stopping exhaust in the processing container; and (b2) A step of supplying the other gas into the processing container while the processing container is being evacuated.

21. A substrate processing apparatus comprising: a processing container for performing processing on a substrate; a nitrogen and hydrogen-containing gas supply system for supplying nitrogen and hydrogen-containing gas into the processing container; a fluorine-containing gas supply system for supplying fluorine-containing gas into the processing container; a temperature regulating unit for regulating the temperature in the processing container; an exhaust system for exhausting the interior of the processing container; and a control unit configured to control the nitrogen- and hydrogen-containing gas supply system, the fluorine-containing gas supply system, the temperature adjustment unit, and the exhaust system so as to perform a process for removing substances adhered to the processing container by performing a cycle including the following processes at a first temperature for a predetermined number of times: (a) a process of supplying one of the nitrogen- and hydrogen-containing gas and the fluorine-containing gas into the processing container after processing a substrate; and (b) a process of supplying another gas, different from the one gas, of the nitrogen- and hydrogen-containing gas and the fluorine-containing gas into the processing container in a state where the one gas remains. in, The following processes are performed in (b): (b1) supplying the other gas into the processing container while stopping the exhaust in the processing container; and (b2) supplying the other gas into the processing container while exhausting the processing container.

22. A computer-readable recording medium having a program recorded thereon, the program causing a substrate processing apparatus to execute the following steps via a computer: A step of removing substances adhered to a processing container of the substrate processing apparatus by performing a cycle including steps (a) and (b) a predetermined number of times at a first temperature: (a) supplying one of a nitrogen- and hydrogen-containing gas and a fluorine-containing gas into the processing container after processing the substrate; and (b) supplying another gas, different from the one gas, of the nitrogen- and hydrogen-containing gas and the fluorine-containing gas into the processing container in which the one gas remains, and In (b): (b1) a step of supplying the other gas into the processing container while stopping the exhaust in the processing container; and (b2) a step of supplying the other gas into the processing container while exhausting the processing container.

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