SUBSTRATE PROCESSING APPARATUS, SUBSTRATE PROCESSING METHOD, SEMICONDUCTOR DEVICE MANUFACTURING METHOD, PROGRAM, AND EXHAUST SYSTEM

Abstract

In the present invention, an atmosphere close to a desired process condition can be constructed even when an exhaust system transitions to a prescribed state, and the deterioration of characteristics of process results is suppressed. An invention is provided having: a first gas supply line that supplies a first gas to a substrate in a processing chamber; a first exhaust line that exhausts the first gas; a first valve provided in the first exhaust line; a second gas supply line that supplies a second gas to the substrate in the processing chamber; a second exhaust line that exhausts the second gas; a second valve provided in the second exhaust line; and a control unit that can control the first valve and the second valve so as to perform a first line change process for exhausting the first gas via the second exhaust line when it is detected that the first exhaust line has transitioned to a prescribed state.

Description

[Technical field]

[0001] The present disclosure relates to a substrate processing apparatus, a substrate processing method, a semiconductor device manufacturing method, a program, and an exhaust system. [Background technology]

[0002] As a substrate processing apparatus used in the manufacturing process of semiconductor device, there is, for example, an apparatus that has a first exhaust system that exhausts raw materials from within the processing chamber and a second exhaust system that exhausts reactants from within the processing chamber, and is configured to reduce the frequency of maintenance of the exhaust systems (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-186574 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique that can suppress deterioration of the characteristics of the processing results even in cases where desired processing conditions may not be obtained depending on the state of the exhaust system. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, a first gas supply line that supplies a first gas to a substrate in a processing chamber; a first exhaust line connected to a first pump and configured to exhaust the first gas supplied to the substrate; a first valve provided in the first exhaust line; a second gas supply line that supplies a second gas to the substrate in the processing chamber; a second exhaust line connected to a second pump and configured to exhaust the second gas supplied to the substrate; a second valve provided in the second exhaust line; a control unit capable of controlling the first valve and the second valve to perform a first line change process of exhausting the first gas supplied to the substrate toward the second pump through the second exhaust line when it is detected that the first exhaust line has transitioned to a predetermined state; The present invention provides a technique having the following features: Effect of the Invention

[0006] According to the present disclosure, even if the exhaust system transitions to a predetermined state, an atmosphere close to the desired processing conditions can be created, and deterioration of the characteristics of the processing result can be suppressed. [Brief description of the drawings]

[0007] [Figure 1] 1 is a vertical cross-sectional view showing a processing furnace of a substrate processing apparatus according to an embodiment of the present disclosure. [Diagram 2] 2 is a cross-sectional view showing a process furnace of the substrate processing apparatus according to the embodiment of the present disclosure, taken along the line AA of FIG. 1. [Diagram 3] FIG. 2 is a block diagram showing a control unit of the substrate processing apparatus according to an embodiment of the present disclosure. [Figure 4] 1 is an explanatory diagram showing a processing operation of an exhaust system of a substrate processing apparatus according to an embodiment of the present disclosure; [Diagram 5] 1A and 1B are explanatory diagrams showing the process operation of switching the exhaust system during a film formation process in a substrate processing apparatus according to an embodiment of the present disclosure, in which (a) shows a normal operation state and (b) shows a state after transition to a predetermined state. [Figure 6] 1A and 1B are explanatory diagrams showing the process operation of switching the exhaust system when a bypass line is used in a substrate processing apparatus according to an embodiment of the present disclosure, in which (a) shows a normal operation state, and (b) shows a state after transition to a predetermined state. [Figure 7] 11 is an explanatory diagram showing a processing operation for switching an exhaust system before maintenance of a substrate processing apparatus according to an embodiment of the present disclosure. FIG.

[0008] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. Note that all drawings used in the following description are schematic, and the dimensional relationship between elements on the drawings, the ratio of elements, etc. do not necessarily match the actual ones. Furthermore, the dimensional relationship between elements and the ratio of elements between multiple drawings do not necessarily match.

[0009] (1) Configuration of the substrate processing device First, a configuration of a substrate processing apparatus according to an embodiment of the present disclosure will be described. Here, as an example of a substrate processing apparatus, we will explain a substrate processing apparatus that is used in one step of a semiconductor device manufacturing process and is a batch-type vertical apparatus that performs film formation processing, etc. on multiple substrates at once.

[0010] (Processing furnace) As shown in FIG. 1, the substrate processing apparatus according to this embodiment includes a processing furnace 202.

[0011] The processing furnace 202 has a heater 207 as a heating means (heating mechanism). 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.

[0012] A reaction tube 203 constituting a reaction vessel (processing vessel) is disposed inside the heater 207 concentrically with the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC), and is formed in a cylindrical shape with a closed upper end and an open lower end.

[0013] A processing chamber 201 is formed in a cylindrical hollow portion of the reaction tube 203. The processing chamber 201 is configured to be capable of accommodating a wafer 200 as a substrate.

[0014] Below the reaction tube 203, a seal cap 219 is provided as a furnace port cover capable of airtightly closing the lower end opening of the reaction tube 203. The seal cap 219 is made of a metal such as SUS and is formed in a disk shape. An O-ring 220 is provided on the upper surface of the seal cap 219 as a seal member that contacts the lower end of the reaction tube 203. Below the seal cap 219, a rotation mechanism 267 is provided for rotating the boat 217 described later. A rotation shaft 255 of the rotation mechanism 267 is connected to the boat 217 through the seal cap 219. The rotation mechanism 267 is configured to rotate the wafers 200 by rotating the boat 217. The seal cap 219 is configured to be vertically raised and lowered by a boat elevator 115 as a lifting mechanism installed outside the reaction tube 203. The boat elevator 115 is configured as a transfer device (transfer mechanism) that transfers the boat 217, that is, the wafers 200, into and out of the processing chamber 201 by raising and lowering the seal cap 219.

[0015] The boat 217 as a substrate support is configured to support a plurality of wafers 200, for example 25 to 200, in multiple stages in a horizontal position and aligned vertically with their centers aligned, i.e., arranged at intervals. The boat 217 is made of a heat-resistant material such as quartz or SiC. At the bottom of the boat 217, heat insulating plates 218 made of a heat-resistant material such as quartz or SiC are supported in multiple stages in a horizontal position.

[0016] A temperature sensor 263 serving as a temperature detector is installed in 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 in the process chamber 201 becomes a desired one. The temperature sensor 263 is installed along the inner wall of the reaction tube 203.

[0017] (Gas Supply System) Nozzles 249a and 249b are provided in the processing chamber 201 so as to penetrate the lower sidewall of the reaction tube 203. Gas supply pipes 232a and 232b are connected to the nozzles 249a and 249b, respectively.

[0018] Gas supply pipes 232a and 232b are provided with mass flow controllers (MFCs) 241a and 241b, which are flow rate controllers (flow rate control parts), and valves 243a and 243b, which are on-off valves, in order from the upstream direction. Gas supply pipes 232c and 232d, which supply inert gas, are connected to the gas supply pipes 232a and 232b downstream of the valves 243a and 243b. Gas supply pipes 232c and 232d are provided with MFCs 241c and 241d and valves 243c and 243d, respectively, in order from the upstream direction.

[0019] As shown in FIG. 2, the nozzles 249a and 249b are provided in a circular space between the inner wall of the reaction tube 203 and the wafers 200 in a plan view, from the lower part to the upper part of the inner wall of the reaction tube 203, so as to rise upward in the arrangement direction of the wafers 200. That is, the nozzles 249a and 249b are provided in a region horizontally surrounding the wafer arrangement region on the side of the wafer arrangement region where the wafers 200 are arranged, so as to extend along the wafer arrangement region. Gas supply holes 250a and 250b for supplying gas are provided on the side of the nozzles 249a and 249b, respectively. The gas supply holes 250a and 250b are opened to face the center of the reaction tube 203, so that gas can be supplied toward the wafers 200. A plurality of gas supply holes 250a and 250b are provided from the lower part to the upper part of the reaction tube 203.

[0020] (First gas supply line) From the gas supply pipe 232a, a halogen-based raw material gas containing a predetermined element (main element) and a halogen element as a raw material gas, which is a first gas, is supplied into the processing chamber 201 via the MFC 241a, the valve 243a, and the nozzle 249a. That is, the gas supply pipe 232a functions as a first gas supply line that supplies the raw material gas, which is the first gas, to the wafer 200 in the processing chamber 201.

[0021] The source gas refers to a gaseous source, for example, a gas obtained by vaporizing a source that is in a liquid state at room temperature and normal pressure, or a source that is in a gaseous state at room temperature and normal pressure. Halogen elements include chlorine (Cl), fluorine (F), bromine (Br), iodine (I), and the like. That is, halogen-based source gases include halogen groups such as chloro, fluoro, bromo, and iodine. For example, a halosilane source gas containing silicon (Si) and Cl as the predetermined elements, that is, a chlorosilane source gas, can be used as the halogen-based source gas. For example, hexachlorodisilane (Si2C6, abbreviated as HCDS) gas can be used as the chlorosilane source gas. As the raw material gas, in addition to HCDS gas, chlorosilane raw material gases containing Si-Cl bonds, such as monochlorosilane (SiH3Cl, abbreviation: MCS) gas, dichlorosilane (SiH2Cl2, abbreviation: DCS), trichlorosilane (SiHCl3, abbreviation: TCS) gas, tetrachlorosilane (SiCl4, abbreviation: STC) gas, and octachlorotrisilane (Si3Cl8, abbreviation: OCTS) gas, can be used.

[0022] That is, the raw material gas as the first gas is a gas containing a main element (e.g., Si) constituting a film (e.g., a Si-containing film) to be formed on the wafer 200. Specifically, the raw material gas as the first gas is, for example, a Si-containing gas. More specifically, the raw material gas as the first gas is, for example, a halosilane-based gas such as a chlorosilane-based gas.

[0023] A raw material supply system (halosilane raw material supply system) is mainly constituted by the gas supply pipe 232a, the MFC 241a, and the valve 243a.

[0024] (Second gas supply line) From the gas supply pipe 232b, a gas containing nitrogen (N) (nitriding gas, nitriding agent) is supplied as a reactant gas, which is a second gas, into the processing chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b. That is, the gas supply pipe 232b functions as a second gas supply line that supplies the reactant gas, which is the second gas, to the wafer 200 in the processing chamber 201.

[0025] The nitriding agent constituting the reactant gas may be, for example, a hydrogen nitride gas, such as ammonia (NH3) gas. In addition to NH3 gas, hydrogen nitride gases containing NH bonds, such as diazene (N2H2) gas, hydrazine (N2H4) gas, and N3H8 gas, may also be used as the reactant gas.

[0026] That is, the reactant gas as the second gas is a gas that does not contain a main element (e.g., Si) constituting a film (e.g., a Si-containing film) to be formed on the wafer 200. Specifically, the reactant gas as the second gas contains at least one of a C-containing gas such as C3H6, an O-containing gas such as O2, and an N- and H-containing gas. The reactant gas as the second gas may contain any of a C-containing gas, an O-containing gas, and an N- and H-containing gas.

[0027] A reactant supply system (nitriding agent supply system) is mainly constituted by the gas supply pipe 232b, the MFC 241b, and the valve 243b.

[0028] (Inert gas supply line) From the gas supply pipes 232c and 232d, an inert gas is supplied into the processing chamber 201 via the MFCs 241c and 241d, the valves 243c and 243d, the gas supply pipes 232a and 232b, and the nozzles 249a and 249b, respectively. That is, the gas supply pipes 232c and 232d function as inert gas supply lines that supply the inert gas into the processing chamber 201.

[0029] As the inert gas, for example, at least one of nitrogen (N2) gas, helium (He) gas, neon (Ne) gas, argon (Ar) gas, and xenon (Xe) gas can be used.

[0030] An inert gas supply system is mainly configured by the gas supply pipes 232c and 232d, the MFCs 241c and 241d, and the valves 243c and 243d.

[0031] (Gas exhaust system) The reaction tube 203 is provided with an exhaust pipe 231 that exhausts the atmosphere inside the processing chamber 201. A pressure sensor 245 serving as a pressure detector (pressure detection unit) that detects the pressure inside the processing chamber 201 is provided on the upstream side of the exhaust pipe 231. The downstream side of the exhaust pipe 231 branches into exhaust pipes 231a and 231b.

[0032] As indicated by diagonal lines in FIG. 1, for example, ribbon-shaped heaters 231h are wound around the outer periphery of exhaust pipe 231 and the outer periphery of the upstream portions of exhaust pipes 231a and 231b as heating means (heating mechanism) for heating them.

[0033] (First exhaust line) The exhaust pipe 231a is connected to a vacuum pump 246a serving as a first vacuum exhaust device. By operating the vacuum pump 246a, the exhaust pipe 231a in the processing chamber 201 functions as a first exhaust line for exhausting the raw material gas, which is a first gas, through the exhaust pipe 231.

[0034] An APC (Auto Pressure Controller) valve 244a serving as a pressure regulator (pressure adjustment unit) is provided in each exhaust pipe 231a. The APC valve 244a functions as a first valve provided in the first exhaust line, and can evacuate and stop the evacuation of the processing chamber 201 by opening and closing the valve while the vacuum pump 246a is operating. Furthermore, the pressure in the processing chamber 201 can be adjusted by adjusting the valve opening based on pressure information detected by a pressure sensor 245 while the vacuum pump 246a is operating.

[0035] A first exhaust system is mainly composed of the exhaust pipe 231, the exhaust pipe 231a, and the APC valve 244a. The vacuum pump 246a may be included in the first exhaust line.

[0036] Furthermore, a first pressure gauge 247a may be provided downstream (on the vacuum pump 246a side) of the APC valve 244a of the exhaust pipe 231. In this case, the first pressure gauge 247a may be considered to be included in the first exhaust line.

[0037] (Second exhaust line) The exhaust pipe 231b is connected to a vacuum pump 246b serving as a second vacuum exhaust device. The vacuum pump 246b is configured to exhaust the reactant gas supplied to the wafer 200 in the processing chamber 201 through the exhaust pipe 231 by operating the vacuum pump 246b. In other words, the exhaust pipe 231b functions as a second exhaust line for exhausting the reactant gas, which is a second gas.

[0038] The exhaust pipe 231b is provided with an APC valve 244b as a pressure regulator (pressure adjustment unit). The APC valve 244b functions as a second valve provided in the second exhaust line, and can evacuate and stop the evacuation of the processing chamber 201 by opening and closing the valve while the vacuum pump 246b is operating. Furthermore, with the vacuum pumps 246a and 246b operating, the valve opening is adjusted based on pressure information detected by the pressure sensor 245, thereby adjusting the pressure in the processing chamber 201.

[0039] A second exhaust system is mainly composed of the exhaust pipe 231, the exhaust pipe 231b, and the APC valve 244b. The vacuum pump 246b may be included in the second exhaust line.

[0040] Furthermore, a second pressure gauge 247b may be provided downstream of the APC valve 244b of the exhaust pipe 231b (on the side of the vacuum pump 246b). In this case, the second pressure gauge 247b may be considered to be included in the second exhaust line.

[0041] Either the first exhaust system or the second exhaust system, or the entire system, may be referred to as an exhaust system. The pressure sensor 245 and the heater 231h may be included in the exhaust system.

[0042] The first and second exhaust systems are alternately used. That is, the first exhaust system is used when exhausting an atmosphere containing raw materials from the processing chamber 201, and the second exhaust system is used when exhausting an atmosphere containing reactants from the processing chamber 201.

[0043] (Bypass line) A bypass line 233 is provided between the exhaust pipe 231a downstream of the APC valve 244a and the exhaust pipe 231b downstream of the APC valve 244b. The bypass line 233 is connected to the exhaust pipe 231a via a valve 244c serving as a third valve, and is connected to the exhaust pipe 231b via a valve 244d serving as a fourth valve.

[0044] A branch point is provided between the valves 244c and 244d in the bypass line 233. The branch point is connected to a gas supply source (not shown) via a valve 248b provided in a pipe 248a connected to the gas supply pipe 232a, so that a predetermined gas (here, a source gas) is supplied to the bypass line 233.

[0045] (controller) The substrate processing apparatus according to this embodiment includes a controller 121 as a control unit (control means).

[0046] 3, the controller 121 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.

[0047] The storage device 121c is composed of, for example, a flash memory, a HDD (Hard Disk Drive), etc. A control program for controlling the operation of the substrate processing apparatus, a process recipe in which the procedures and conditions of the substrate processing described later are described, etc. are readably stored in the storage device 121c. The process recipe is a combination of procedures in the substrate processing step described later that are executed by the controller 121 to obtain a predetermined result, and functions as a program. Hereinafter, the process recipe and the control program are collectively referred to simply as a program. In addition, the process recipe is also simply referred to as a recipe. In this specification, when the word program is used, it may include only a recipe, only a control program, or both. The RAM 121b is configured as a memory area (work area) in which the programs and data read by the CPU 121a are temporarily stored.

[0048] The I / O port 121d is connected to the above-mentioned MFCs 241a to 241h, valves 243a to 243h, 244c, and 244d, pressure sensor 245, APC valves 244a and 244b, vacuum pumps 246a and 246b, heaters 207 and 231h, temperature sensor 263, rotation mechanism 267, boat elevator 115, and the like.

[0049] 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 an input of an operation command from the input / output device 122, etc. The CPU 121a is configured to be capable of controlling the flow rate adjustment operation of various gases by the MFCs 241a to 241h, the opening and closing operations of the valves 243a to 243h, 244c, 244d, and 248b, the opening and closing operations of the APC valves 244a and 244b and the pressure adjustment operation by the APC valves 244a and 244b based on the pressure sensor 245, the start and stop of the vacuum pumps 246a and 246b, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the temperature adjustment operation of the heater 231h, 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, etc., in accordance with the contents of the read recipe.

[0050] The controller 121 can be configured by installing the above-mentioned program stored in an external storage device (for example, a magnetic disk such as a hard disk, an optical disk such as a CD, a magneto-optical disk such as an MO, or a semiconductor memory such as a USB memory) 123 into a computer. The storage device 121c and the external storage device 123 are configured as computer-readable recording media. Hereinafter, these are collectively referred to simply as recording media. When the term recording media is used in this specification, it may include only the storage device 121c alone, only the external storage device 123 alone, or both. 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.

[0051] (Exhaust system) The substrate processing apparatus configured as above constitutes an exhaust system together with the vacuum pumps 246a and 246b as a vacuum exhaust device. That is, the exhaust system in the present disclosure is configured to include the substrate processing apparatus, the vacuum pump 246a as a first pump, and the vacuum pump 246b as a second pump.

[0052] (2) Substrate processing procedure Next, a procedure for forming a silicon nitride film (SiN film) on a wafer 200 as a substrate as one step of a manufacturing process of a semiconductor device using the substrate processing apparatus having the above-mentioned configuration will be described. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by a controller 121.

[0053] In this specification, the term "wafer" may mean "the wafer itself" or "a laminate (assembly) of a wafer and a predetermined layer or film formed on its surface", i.e., the wafer may include the predetermined layer or film formed on the surface. In addition, in this specification, the term "surface of a wafer" may mean "the surface (exposed surface) of the wafer itself" or "the surface of a predetermined layer or film formed on the wafer, i.e., the outermost surface of the wafer as a laminate".

[0054] Therefore, in this specification, when it is stated that "a predetermined gas is supplied to the wafer", it may mean "a predetermined gas is directly supplied to the surface (exposed surface) of the wafer itself" or "a predetermined gas is supplied to a layer or film formed on the wafer, i.e., to the outermost surface of the wafer as a laminate". In addition, when it is stated that "a predetermined layer (or film) is formed on the wafer", it may mean "a predetermined layer (or film) is directly formed on the surface (exposed surface) of the wafer itself" or "a predetermined layer (or film) is formed on the layer or film formed on the wafer, i.e., on the outermost surface of the wafer as a laminate".

[0055] Furthermore, the use of the word "substrate" in this specification is the same as the use of the word "wafer", and in that case, the "wafer" can be replaced with "substrate" in the above explanation.

[0056] The substrate processing steps will be described below.

[0057] (Wafer charge and boat load) A plurality of wafers 200 are loaded into the boat 217 (wafer charge). Then, the boat 217 supporting the plurality of wafers 200 is lifted by the boat elevator 115 and carried into the processing chamber 201 (boat load). In this state, the seal cap 219 seals the lower end of the reaction tube 203 via the O-ring 220.

[0058] (Pressure and temperature regulation) The processing chamber 201 is evacuated (reduced pressure exhausted) by the first exhaust system and the second exhaust system so that the processing chamber 201, i.e., the space in which the wafer 200 exists, reaches a desired pressure (vacuum level). At this time, the pressure in the processing chamber 201 is measured by a pressure sensor 245, and the APC valves 244a, 244b are feedback-controlled based on the measured pressure information. The vacuum pumps 246a, 246b are each kept in a constantly operating state at least until the processing of the wafer 200 is completed.

[0059] The heater 207 heats the wafer 200 in the processing chamber 201 to a predetermined temperature (film formation temperature). At this time, the power supply to the heater 207 is feedback-controlled based on temperature information detected by the temperature sensor 263 to achieve a predetermined temperature distribution in the processing chamber 201. The heater 231h heats the exhaust pipe 231 and the exhaust pipes 231a and 231b upstream of the APC valves 244a and 244b to a predetermined temperature (a temperature that can suppress raw material adsorption). The above-mentioned heating by the heaters 207 and 231h continues at least until the processing of the wafer 200 is completed.

[0060] Furthermore, the rotation mechanism 267 starts to rotate the boat 217 and the wafers 200. The rotation of the boat 217 and the wafers 200 continues at least until the processing of the wafers 200 is completed.

[0061] (Deposition step) Thereafter, as a film forming step, the following steps 1A and 2A are executed in sequence.

[0062] [Step 1A] In this step, a first gas (source gas) is supplied to the wafer 200. Specifically, as shown in the upper left of FIG. 4, the APC valve 244b is fully closed, and the APC valve 244a is open, and the valve 243a is opened to allow the source gas to flow into the gas supply pipe 232a. The source gas is adjusted in flow rate by the MFC 241a, and is supplied into the processing chamber 201 through the nozzle 249a, and is exhausted from the exhaust pipe 231a through the exhaust pipe 231, that is, from the first exhaust system. At this time, the source gas is supplied to the wafer 200. At the same time, the valve 243c is opened to allow an inert gas to flow into the gas supply pipe 232c. The inert gas is supplied into the processing chamber 201 together with the source gas, and is exhausted from the exhaust pipe 231a. Also, in order to prevent the source gas from entering the nozzle 249b, the valve 243d is opened to allow the inert gas to flow into the gas supply pipe 232d. The inert gas is supplied into the processing chamber 201 via a gas supply pipe 232b and a nozzle 249b, and is exhausted from an exhaust pipe 231a.

[0063] Here, when chlorosilane gas is used as the source gas, a Si-containing layer containing Cl is formed on the top surface of the wafer 200 by supplying the source gas to the wafer 200. The Si-containing layer containing Cl may be a Si layer containing Cl, an adsorption layer of source gas molecules, or may contain both. Hereinafter, the Si-containing layer containing Cl is also simply referred to as a Si-containing layer.

[0064] When the Si-containing layer is formed on the wafer 200, the valve 243a is closed to stop the supply of the source gas. At this time, as shown in the upper right of FIG. 4, the open / closed states of the APC valves 244a and 244b are maintained as shown in the upper left of FIG. 4 for a predetermined time. As a result, the source gas remaining in the processing chamber 201 is exhausted from the first exhaust system. At this time, the valves 243c and 243d are kept open to maintain the supply of the inert gas into the processing chamber 201. The inert gas acts as a purge gas, which promotes the exhaust of the remaining gas (source gas) from the processing chamber 201, the exhaust pipe 231, and the exhaust pipe 231a.

[0065] [Step 2A] After step 1A is completed, a second gas (reactant gas) is supplied to the wafer 200. In this step, as shown in the lower left of FIG. 4, the APC valve 244a is fully closed, and the APC valve 244b is open. The valves 243b to 243d are controlled to open and close in the same manner as the valves 243a, 243c, and 243d in step 1A, and the reactant gas is allowed to flow into the gas supply pipe 232b. The reactant gas is adjusted in flow rate by the MFC 241b, supplied into the process chamber 201 through the nozzle 249b, and exhausted from the exhaust pipe 231b, i.e., the second exhaust system, through the exhaust pipe 231. At this time, the reactant gas is supplied to the wafer 200.

[0066] Here, when NH3 gas is used as the reactant gas, at least a part of the Si-containing layer formed on the wafer 200 can be modified (nitrided) by supplying the reactant gas to the wafer 200. As a result, a layer containing Si and N, i.e., a silicon nitride layer (SiN layer), is formed on the wafer 200. When the SiN layer is formed, impurities such as Cl contained in the Si-containing layer are separated from this layer in the process of the modification reaction, and are discharged from the processing chamber 201 as a gaseous substance containing at least Cl. As a result, the SiN layer becomes a layer with fewer impurities such as Cl compared to the Si-containing layer.

[0067] Once the SiN layer is formed on the wafer 200, the valve 243b is closed to stop the supply of the reactant gas. At this time, as shown in the lower right of FIG. 4, the open / closed states of the APC valves 244a and 244b are maintained as shown in the lower left of FIG. 4 for a predetermined time. As a result, the reactant gas remaining in the process chamber 201 is exhausted from the second exhaust system. At this time, the valves 243c and 243d are kept open to promote exhaust of the remaining gas (reactant gas) from the process chamber 201, the exhaust pipe 231, and the exhaust pipe 231b.

[0068] [Perform the specified number of times] By repeating the cycle of alternately performing the above-mentioned steps 1A and 2A a predetermined number of times (n times (n is an integer equal to or greater than 1)), the source gas and the reactant gas flow intermittently and non-simultaneously a predetermined number of times in the processing chamber 201. This allows a film (e.g., a SiN film) of a predetermined thickness to be formed on the wafer 200. It is preferable to repeat the above-mentioned cycle multiple times.

[0069] (After purging and atmospheric pressure recovery) After the formation of the SiN film on the wafer 200 is completed, an inert gas is supplied into the processing chamber 201 from each of the gas supply pipes 232c and 232d, and the processing chamber 201 is evacuated to a vacuum state by the first and second exhaust systems. This causes the processing chamber 201 to be purged with the inert gas, and gas and reaction by-products remaining in the processing chamber 201 are removed from the processing chamber 201 (after-purging). 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 (return to atmospheric pressure).

[0070] (Boat unloading and wafer discharging) The seal cap 219 is lowered by the boat elevator 115 to open the bottom end of the reaction tube 203. Then, the processed wafers 200 are carried out from the bottom end of the reaction tube 203 to the outside of the reaction tube 203 while being supported by the boat 217 (boat unloading). The processed wafers 200 are taken out of the boat 217 (wafer discharging).

[0071] (3) Processing operation when an abnormality occurs in the exhaust system As described above, in the substrate processing step, a first gas (source gas) and a second gas (reactant gas) are supplied to the wafer 200 in the processing chamber 201 to form a desired layer (for example, a SiN layer) on the wafer 200. At that time, the substrate processing apparatus is provided with a first exhaust system having an exhaust pipe 231a which is a first exhaust line, and a second exhaust system having an exhaust pipe 231b which is a second exhaust line. Each of the exhaust pipes 231a and 231b is a vacuum pump specification as a first pump. Therefore, even when a source gas and a reactant gas are supplied to the wafer 200, each gas can be exhausted separately, such as exhausting the source gas through the first exhaust system and exhausting the reactant gas through the second exhaust system. This reduces the amount of by-products accumulated in the exhaust system, and extends the period until pump maintenance is required, which results in a reduction in the frequency of maintenance of the exhaust system.

[0072] However, even in the case of a dual pump specification, by-products may accumulate when the substrate processing apparatus is operated for a long period of time, which may cause a performance degradation of the exhaust system including the exhaust line. The performance degradation of the exhaust system may be, for example, at least one of a performance degradation of the vacuum pump, a performance degradation of the valve, and a performance (conductance) degradation of the exhaust pipe. In particular, the first pump, the vacuum pump 246a, is expected to have a higher failure rate than the others because by-products are likely to adhere to it, and there is a concern that the performance degradation of the exhaust system may occur due to the occurrence of failure.

[0073] A decrease in the performance of the exhaust system may be a factor that makes it impossible to form a desired film in the processing chamber 201. Specifically, for example, due to a decrease in the exhaust rate, the source gas may not be exhausted before it decomposes in the processing chamber 201, which may result in the generation of particles in the processing chamber 201, resulting in poor coverage or the like. In other words, a decrease in the performance of the exhaust system may cause the characteristics of the film formed on the wafer 200 to deteriorate.

[0074] Therefore, in the substrate processing apparatus according to this embodiment, the controller 121 monitors the state of the exhaust system, and when the exhaust system transitions to a predetermined state, the controller 121 performs the following control process. The control process by the controller 121 will be described below. Here, the state of the exhaust system may include at least one of the opening degree of each valve, the pressure of the first exhaust line, the pressure of the second exhaust line, and the state of the pumps 246a and 246b.

[0075] (During film formation process) 5(a), in step 1A in the film forming step of the substrate processing process described above, the controller 121 opens the APC valve 244a (white circle in the figure) and closes the APC valve 244b (black circle in the figure). The controller 121 also closes the valves 244c and 244d in the bypass line 233. As a result, the source gas is exhausted by the first exhaust system through the exhaust pipe 231a as the first exhaust line by the operation of the vacuum pump 246a.

[0076] At this time, the controller 121 monitors whether the exhaust pipe 231a serving as the first exhaust line is in a predetermined state. The "predetermined state" here refers to a state in which there is a high possibility that an abnormality will occur in the exhaust performed through the exhaust pipe 231a. Specifically, for example, at least one of the states (i) to (v) described below may be applicable.

[0077] (i) When a decrease in the amount of exhaust air discharged through the exhaust pipe 231a occurs, the controller 121 determines that the exhaust pipe 231a has transitioned to a predetermined state. The presence or absence of a decrease in the amount of exhaust air discharged may be determined, for example, by detecting the time it takes for either or both of the pressure gauge 245 and the first pressure gauge 247a to reach a predetermined pressure based on a predefined pressure-time curve during exhaust, or by detecting that the pressure does not fall within a predetermined pressure range within a set time. Note that the pressure is measured using either or both of the pressure gauge 245 and the first pressure gauge 247a during step 1A. If the pressure is measured outside step 1A, the pressure is measured using the first pressure gauge 247a.

[0078] (ii) When the vacuum pump 246a connected to the exhaust pipe 231a suddenly stops, the controller 121 determines that the exhaust pipe 231a has transitioned to a predetermined state. The presence or absence of the sudden stop of the vacuum pump 246a may be determined by, for example, the controller 121 monitoring the operating state of the vacuum pump 246a and detecting an alarm signal or the like from the vacuum pump 246a.

[0079] (iii) When an increase in the pump load occurs for the vacuum pump 246a connected to the exhaust pipe 231a, the controller 121 determines that the exhaust pipe 231a has transitioned to a predetermined state. Whether or not the pump load has increased may be determined, for example, by monitoring the load current value of the vacuum pump 246a and comparing the load current value with a predetermined threshold value since the current value increases as the pump load increases.

[0080] (iv) When a valve opening defect occurs in the APC valve 244a provided in the exhaust pipe 231a, the controller 121 determines that the exhaust pipe 231a has transitioned to a predetermined state. The presence or absence of a valve opening defect may be determined based on a valve opening adjustment signal for the APC valve 244a and a pressure detection result in the process chamber 201, since the pressure in the process chamber 201 cannot be adjusted as desired when the valve opening defect occurs, for example.

[0081] The opening of the APC valve 244a may be determined based on the pressure detection result in the first exhaust pipe 231a using the first pressure gauge 247a. For example, when the value of the first pressure gauge 247a is equal to or higher than a predetermined pressure, it is determined that the APC valve 244a is open. Here, the predetermined pressure is, for example, a pressure of about 10 Pa to 100 Pa. Also, when the value of the first pressure gauge 247a is equal to or lower than the predetermined pressure, it is determined that the APC valve 244a is closed. In this case, the predetermined pressure is, for example, a pressure of about 0.1 Pa to 1 Pa.

[0082] (v) When the APC valve 244a provided in the exhaust pipe 231a becomes stuck, the controller 121 determines that the exhaust pipe 231a has transitioned to a predetermined state. The presence or absence of the stuck valve may be determined, for example, in the same manner as in the case of the valve opening failure described above, or may be determined by detecting an alarm signal or the like from the APC valve 244a while monitoring the operating state of the APC valve 244a.

[0083] When at least one of the above (i) to (v) is satisfied, the controller 121 determines that the exhaust pipe 231a has transitioned to a predetermined state. Then, when it detects that the exhaust pipe 231a has transitioned to a predetermined state, the controller 121 performs a line change process (hereinafter, referred to as a first line change process) for changing the gas flow. The first line change process is a process for exhausting the source gas supplied to the wafer 200 toward the vacuum pump 246b through the exhaust pipe 231b as a second exhaust line, instead of the exhaust pipe 231a as a first exhaust line. In other words, the first line change process is a process for switching exhaust by the first exhaust system to exhaust by the second exhaust system.

[0084] Specifically, when the controller 121 detects that the exhaust pipe 231a has transitioned to a predetermined state, the controller 121 controls the operation of each valve so that the APC valve 244a is fully closed and the APC valve 244b is open, as shown in Fig. 5(b). At this time, the valves 244c and 244d in the bypass line 233 are kept fully closed.

[0085] By such valve control operation, the source gas supplied to the wafer 200 is exhausted by the second exhaust system through the exhaust pipe 231b as the second exhaust line by the operation of the vacuum pump 246b.

[0086] Therefore, even if the exhaust pipe 231a transitions to a predetermined state (e.g., if the exhaust volume decreases), by switching the exhaust path from the first exhaust system to the second exhaust system, an atmosphere close to the desired film formation conditions can be created in the processing chamber 201, and deterioration of the characteristics of the film formed on the wafer 200 can be suppressed.

[0087] Specifically, for example, by detecting an alarm signal issued when the vacuum pump 246a breaks down and stops, if one of the pumps in the dual pump specification breaks down, film formation can be continued using only the remaining pump, and as a result, product lot-out can be prevented. In other words, even if a pump suddenly breaks down, for example, the exhaust line can be automatically switched accordingly, making it possible to continue processing the wafers 200.

[0088] (When using bypass line) When step 1A in the film forming step of the above-mentioned substrate processing process is completed and the raw material gas does not flow in the processing chamber 201, as shown in FIG. 6(a), the exhaust pipe 231a may be supplied with the raw material gas as the predetermined gas from the bypass line 233. Specifically, the controller 121 sets the APC valve 244a in a fully closed state (black circle state in the figure) and sets the valve 244c in the bypass line 233 in an open state (white circle state in the figure). The controller 121 also sets the APC valve 244b and the valve 244d in the bypass line 233 in a fully closed state. In addition, the valve 248b provided in the pipe 248a connected to the first gas supply line is set in an open state. This allows the raw material gas present in the first gas supply line to be exhausted to the bypass line 233 via the pipe 248a. The raw material gas exhausted to the bypass line 233 is exhausted from the exhaust pipe 231a to the pump 246a.

[0089] In this case, similarly to the above-mentioned normal operation, when the controller 121 detects that the exhaust pipe 231a has transitioned to a predetermined state, the controller 121 performs a line change process (hereinafter referred to as a second line change process) to change the gas flow. The second line change process is a process of exhausting the source gas in the first gas supply line toward the vacuum pump 246b via the bypass line 233 and the exhaust pipe 231b as the second exhaust line, instead of the exhaust pipe 231a as the first exhaust line. In other words, the second line change process is a process of switching from exhaust by the first exhaust system to exhaust by the second exhaust system while using the bypass line 233.

[0090] Specifically, when the controller 121 detects that the exhaust pipe 231a has transitioned to a predetermined state, the controller 121 controls the operation of each of the valves 244c in the bypass line 233 to be fully closed and the valve 244d in the bypass line 233 to be open, as shown in Fig. 6(b). At this time, the APC valves 244a and 244b are kept fully closed.

[0091] By such valve control operation, the source gas in the first gas supply line is exhausted by the second exhaust system through the bypass line 233 and the exhaust pipe 231b as the second exhaust line by the operation of the vacuum pump 246b.

[0092] Therefore, even if the exhaust pipe 231a transitions to a predetermined state (for example, if the exhaust rate is reduced), the raw material gas present in the first gas supply line and the raw material gas whose characteristics have changed can be exhausted through the bypass line 233 and the exhaust pipe 231b by switching the exhaust path, without passing through the processing chamber 201. This makes it possible to prevent the raw material gas whose characteristics have changed from being supplied to the processing chamber 201, and is very effective in creating an atmosphere close to the desired film formation conditions and preventing the deterioration of the characteristics of the formed film. Note that the raw material gas whose characteristics (properties) have changed here means at least one of a partially decomposed gas, an aggregated gas, a gas with a different raw material concentration, and a gas with a different pressure.

[0093] (Relationship between the first line change process and the second line change process) As described above, when the controller 121 detects that the exhaust pipe 231a has transitioned to a predetermined state, the controller 121 controls the opening and closing operations of the APC valves 244a, 244b and the valves 244c, 244d so as to perform a first line change process while the wafer 200 is being processed in the processing chamber 201, and to perform a second line change process after the first line change process. That is, when the exhaust pipe 231a transitions to a predetermined state, the source gas is exhausted from the exhaust pipe 231b as a second exhaust line during the film formation process, and the residual gas including the source gas is exhausted from the bypass line 233 to the exhaust pipe 231b in the bypass line purging after the film formation.

[0094] In this way, by performing the second line change process after the first line change process, the gas exhaust in the bypass line 233 is performed after the film formation, so that it is possible to suppress a sudden change in the processing environment during the film formation process. A sudden change in the processing environment means that the source gas exhausted to the exhaust pipe 231a via the bypass line 233 flows back toward the processing chamber 201 for some reason, or that the source gas in an unexpected state enters the exhaust pipe 231a and affects the film formation process. Therefore, it is possible to improve the processing uniformity for each wafer 200 (each batch) for the wafers 200 processed in the processing chamber 201.

[0095] (Before equipment maintenance) In the substrate processing apparatus according to this embodiment, apparatus maintenance (e.g., replacement of pumps, valves, pipes, etc.) may be performed when the above-described substrate processing steps are not being performed. In order to perform the apparatus maintenance, it is necessary to exhaust the residual gas in the exhaust pipe 231a serving as the first exhaust line beforehand.

[0096] Therefore, when the controller 121 detects that the exhaust pipe 231a has transitioned to a predetermined state before the maintenance of the apparatus, the controller 121 performs the following control process. That is, when the processing of the wafer 200 is not being performed in the processing chamber 201, the controller 121 performs a line change process (hereinafter, referred to as a third line change process) for changing the gas flow. The third line change process is a process for exhausting the atmosphere in the exhaust pipe 231a as the first exhaust line from the exhaust pipe 231b as the second exhaust line via the bypass line 233.

[0097] 7, before the apparatus maintenance when the wafer 200 is not being processed in the processing chamber 201. At this time, the APC valves 244a and 244b are closed. That is, in the third line changing process, the APC valves 244a and 244b are both substantially closed, and the valves 244c and 244d in the bypass line 233 are opened.

[0098] By such valve control operation, the atmosphere in the exhaust pipe 231a is exhausted by the second exhaust system through the bypass line 233 and the exhaust pipe 231b by the operation of the vacuum pump 246b.

[0099] Therefore, even if the exhaust pipe 231a transitions to a predetermined state before the maintenance of the apparatus, by switching the exhaust path, it is possible to exhaust the atmosphere in the exhaust pipe 231a (e.g., residual source gas) through the bypass line 233 and the exhaust pipe 231b without passing through the processing chamber 201. That is, it is possible to prevent particles generated in the exhaust pipe 231a, source gas whose properties have changed, and the like from entering the processing chamber 201. Therefore, it is possible to prevent a change in the processing environment in the processing chamber 201.

[0100] (State transition determination) The first line change process, the second line change process, and the third line change process described above are all performed in response to the exhaust pipe 231a transitioning to a predetermined state. To this end, the controller 121 monitors the state of the exhaust pipe 231a and determines whether the exhaust pipe 231a has transitioned to a predetermined state. This determination can be performed based on whether at least one of (i) to (v) applies as described above, but may also be performed as described below.

[0101] For example, when determining the state of the exhaust pipe 231a, the controller 121 supplies an inert gas as an inert gas to the processing chamber 201 from the gas supply pipes 232c and 232d as an inert gas supply line constituting an inert gas supply system. Then, the controller 121 detects the pressure state in the exhaust pipe 231a when the inert gas is exhausted from the exhaust pipe 231a as the first exhaust line. As a result, if the pressure state in the exhaust pipe 231a is not within a predetermined normal state, the controller 121 determines that the exhaust pipe 231a has transitioned to a predetermined state. Here, the pressure in the exhaust pipe 231a is measured by either or both of the pressure gauge 245 and the first pressure gauge 247a.

[0102] That is, the controller 121 judges whether the exhaust pipe 231a has transitioned to a predetermined state by using the supply of inert gas from the inert gas supply line. In this way, by making the judgment by using the supply of inert gas, the first line change process or the like is not performed during the supply of the process gas such as the source gas or the reactant gas, and as a result, it is possible to avoid unexpected film formation.

[0103] Also, for example, the controller 121 may determine whether the exhaust pipe 231a has transitioned to a predetermined state before the supply of the first gas (source gas). Before the supply of the source gas includes before the start of a film formation step in the substrate processing process, before the supply of the source gas during the repetition of multiple cycles, etc. In this way, by performing the determination before the supply of the source gas, the first line change process, etc. is not performed during the supply of the source gas, and as a result, it is possible to avoid unexpected film formation.

[0104] Also, for example, the controller 121 may determine whether the exhaust pipe 231a has transitioned to a predetermined state between the supply of the first gas (source gas) and the supply of the second gas (reactant gas). In this way, by performing the determination between the supply of the source gas and the supply of the reactant gas, the first line change process or the like is not performed during the supply of the reactant gas, and as a result, it is possible to avoid unexpected film formation.

[0105] Also, for example, the controller 121 may determine whether the exhaust pipe 231a has transitioned to a predetermined state after the second gas (reactant gas) is supplied. After the reactant gas is supplied includes after the film formation step in the substrate processing process is completed, after the reactant gas is supplied during the repetition of multiple cycles (before the raw material gas is supplied), and the like. In this way, if the determination is made after the reactant gas is supplied, the first line change process and the like are not performed during the supply of the reactant gas, and as a result, it is possible to avoid unexpected film formation. Also, by making the determination after the film formation process, it becomes possible to determine whether the film formation process on the next wafer 200 can be performed. Also, if the determination is made during a cycle, it becomes possible to easily grasp the fact that the line change process has been performed in the Nth cycle.

[0106] (Alarm notification) When the controller 121 detects that the exhaust pipe 231a has transitioned to a predetermined state, the controller 121 performs a first line change process or the like, and may issue an alarm at that time. In other words, the controller 121 may issue an alarm in response to detection that the exhaust pipe 231a has transitioned to a predetermined state.

[0107] The alarm notification may be by any method capable of notifying that a state transition has occurred, such as sound output using a speaker, light display output using a light, display output of characters or images using a display screen, or output of an alarm signal to a higher-level device using a communication line.

[0108] By issuing such an alarm notification, the user of the substrate processing apparatus to which the notification is sent can easily and accurately recognize that substrate processing is being performed under conditions other than the desired conditions, or that the substrate processing apparatus is in an abnormal state.

[0109] When issuing an alarm, the controller 121 may, after issuing the alarm, continue the processing until the processing of the wafer 200 in the processing chamber 201 is completed. Furthermore, the controller 121 may set the processing chamber 201 in a state in which the next substrate processing is not started after the processing of the wafer 200 in the processing chamber 201 is completed. That is, based on the alarm, the controller 121 may end the ongoing processing but not start a new processing, and set the substrate processing apparatus in a hold state in which the substrate processing apparatus is stopped in a state before the start of the recipe.

[0110] In this way, by putting the substrate processing apparatus into a hold state in response to an alarm, the next new process can be stopped before it is started, thereby preventing substrate processing from being performed under conditions other than the desired conditions.

[0111] Furthermore, when an alarm is issued, the controller 121 may be configured to be able to transmit information on the wafer 200 processed in the state where the alarm was issued, in addition to information that the alarm was issued, to a higher-level device (host device) using a communication line. In this way, if the information on the wafer 200 processed in the state where the alarm was issued can be transmitted, the higher-level device can easily identify the cause of the yield deterioration based on the transmitted information on the wafer 200.

[0112] The controller 121 does not necessarily need to transmit both the alarm notification information and the information on the wafer 200, but may be configured to transmit at least one of them to a higher-level device. Even in this case, the higher-level device can obtain information that is useful for grasping the state of the substrate processing apparatus and the processing wafer 200.

[0113] (4) Effects of this embodiment According to the present embodiment, one or more of the following advantages are achieved.

[0114] (a) According to this embodiment, when it is detected that the exhaust pipe 231a as the first exhaust line has transitioned to a predetermined state, a first line change process is performed to exhaust the source gas supplied to the wafer 200 through the exhaust pipe 231b as the second exhaust line. Therefore, even if the exhaust pipe 231a transitions to a predetermined state, an atmosphere close to the desired film formation conditions can be created in the processing chamber 201 by switching the exhaust path from the first exhaust system to the second exhaust system, and deterioration of the characteristics of the film formed on the wafer 200 can be suppressed. Specifically, even if a sudden pump failure occurs, for example, the exhaust line can be automatically switched accordingly, making it possible to continue processing the wafer 200.

[0115] (b) According to this embodiment, when it is detected that the exhaust pipe 231a as the first exhaust line has transitioned to a predetermined state, a second line change process is performed to exhaust the source gas present in the first gas supply line through the bypass line 233 and the exhaust pipe 231b as the second exhaust line. Therefore, even if the exhaust pipe 231a has transitioned to a predetermined state, it is possible to exhaust the source gas present in the first gas supply line, whose characteristics have changed, through the bypass line 233 and the exhaust pipe 231b without passing through the processing chamber 201, by switching the exhaust path. This is also very effective in creating an atmosphere close to the desired film formation conditions and suppressing deterioration of the characteristics of the formed film.

[0116] (c) According to this embodiment, the first line change process is performed while the wafers 200 are being processed in the processing chamber 201, and the second line change process is performed after the first line change process. Therefore, gas exhaust in the bypass line 233 is performed after the film formation, so that a sudden change in the processing environment during the film formation process can be suppressed, and the processing uniformity of each wafer 200 (each batch) can be improved for the wafers 200 processed in the processing chamber 201.

[0117] (d) According to this embodiment, when the wafer 200 is not being processed in the processing chamber 201, a third line change process is performed in which the atmosphere in the exhaust pipe 231a as the first exhaust line is exhausted from the exhaust pipe 231b as the second exhaust line via the bypass line 233. Therefore, even if the exhaust pipe 231a transitions to a predetermined state before the apparatus maintenance, the atmosphere in the exhaust pipe 231a (e.g., residual raw material gas) can be exhausted through the bypass line 233 and the exhaust pipe 231b without passing through the processing chamber 201 by switching the exhaust path. In other words, it is possible to prevent particles generated in the exhaust pipe 231a and raw material gas whose properties have changed from entering the processing chamber 201, and as a result, it is possible to prevent changes in the processing environment in the processing chamber 201.

[0118] (e) According to the present embodiment, in determining the state of the exhaust pipe 231a, an inert gas is supplied from the gas supply pipes 232c and 232d as an inert gas supply line into the processing chamber 201, and the pressure state in the exhaust pipe 231a when the inert gas is exhausted from the exhaust pipe 231a is detected to determine whether the exhaust pipe 231a has transitioned to a predetermined state. In this way, by using the supply of inert gas to determine the state of the exhaust pipe 231a, the first line change process or the like is not performed during the supply of processing gas such as source gas or reactant gas, and as a result, it is possible to avoid unexpected film formation.

[0119] (f) According to the present embodiment, whether the exhaust pipe 231a has transitioned to a predetermined state is determined before the supply of the first gas (source gas). Therefore, the first line change process or the like is not performed during the supply of the source gas, and as a result, it is possible to avoid unexpected film formation.

[0120] (g) According to this embodiment, the determination of whether the exhaust pipe 231a has transitioned to a predetermined state is performed between the supply of the first gas (source gas) and the supply of the second gas (reactant gas). Therefore, the first line change process or the like is not performed during the supply of the reactant gas, and as a result, unexpected film formation can be avoided.

[0121] (h) According to this embodiment, the determination as to whether the exhaust pipe 231a has transitioned to a predetermined state is performed after the second gas (reactant gas) is supplied. Therefore, the first line change process or the like is not performed during the supply of the reactant gas, and as a result, it is possible to avoid unexpected film formation. Furthermore, by making the determination after the film formation process, it becomes possible to determine whether the film formation process on the next wafer 200 can be performed. Furthermore, if the determination is made during a cycle, it becomes possible to easily grasp the fact that the line change process has been performed in the Nth cycle.

[0122] (i) According to the present embodiment, an alarm is issued in response to detection of a transition of the exhaust pipe 231a serving as the first exhaust line to a predetermined state, so that a user of the substrate processing apparatus to which the alarm is issued can easily and accurately recognize that substrate processing is being performed under conditions different from desired conditions, that the substrate processing apparatus is in an abnormal state, etc.

[0123] (j) According to this embodiment, after an alarm is issued, the processing of the wafer 200 in the processing chamber 201 is continued until the processing is completed. Then, after the processing of the wafer 200 in the processing chamber 201 is completed, a state is established in which the next substrate processing is not started. Therefore, based on the alarm, the ongoing processing is terminated, but a new processing is not started, and a hold state is established in which the substrate processing apparatus is stopped in a state before the start of the recipe, thereby making it possible to prevent substrate processing from being performed under conditions different from desired conditions.

[0124] (k) According to the present embodiment, it is possible to transmit to a higher-level device either or both of the alarm notification information and the information on the wafer 200 processed in the alarm state. Therefore, the higher-level device can obtain information that is useful for grasping the state of the substrate processing apparatus and the processed wafer 200. In particular, it becomes easy to identify the cause of the yield deterioration based on the transmitted information on the wafer 200.

[0125] (l) In this embodiment, the raw material gas, which is the first gas, is a gas containing a main element constituting the film to be formed on the wafer 200, specifically a Si-containing gas, and more specifically a halosilane-based gas such as a chlorosilane-based gas. The reactant gas, which is the second gas, is a gas that does not contain a main element constituting the film to be formed on the wafer 200, specifically a gas that contains at least one of a C-containing gas, an O-containing gas, and an N- and H-containing gas. The reactant gas, which is the second gas, may contain, for example, any of a C-containing gas, an O-containing gas, and an N- and H-containing gas. By using such a type of gas, there is a risk that the exhaust pipe 231a as the first exhaust line will become abnormal during processing. However, by performing a first line change process or the like when the exhaust pipe 231a transitions to a predetermined state, it becomes possible to continue processing the wafer 200 even if the exhaust pipe 231a as the first exhaust line becomes abnormal.

[0126] (m) In this embodiment, at least one of a Si-containing gas, a C-containing gas, an O-containing gas, and an N- and H-containing gas is intermittently and non-simultaneously supplied into the processing chamber 201. In addition, all of a Si-containing gas, a C-containing gas, an O-containing gas, and an N- and H-containing gas may be intermittently and non-simultaneously supplied into the processing chamber 201. Such processing tends to take a long time, and there is a risk that the exhaust pipe 231a serving as the first exhaust line will become abnormal during processing. However, when the exhaust pipe 231a transitions to a predetermined state, a first line change process or the like is performed, so that processing of the wafer 200 can be continued even if the exhaust pipe 231a serving as the first exhaust line becomes abnormal.

[0127] (5) Modifications, etc. Although one embodiment of the present disclosure has been specifically described above, the present disclosure is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit and scope of the present disclosure.

[0128] For example, in the above embodiment, the exhaust pipe 231a is the first exhaust line, the exhaust pipe 231b is the second exhaust line, the vacuum pump 246a is the first pump, and the vacuum pump 246b is the second pump. However, the correspondence may be reversed. In other words, the controller 121 may detect whether the exhaust pipe 231b has transitioned to a predetermined state, and perform control to switch the exhaust system depending on the result.

[0129] In addition, a gas containing oxygen (oxidizer) may be added as a reactant gas, which is the second gas. As the oxidizer, in addition to H2O gas, O-containing gases containing OH bonds such as hydrogen peroxide (H2O2) gas, and O-containing gases containing OO bonds but not OH bonds such as oxygen (O2) gas, ozone (O3) gas, hydrogen (H2) gas + O2 gas, and H2 gas + O3 gas can be used. In addition, a gas containing a catalyst or carbon may be added as a reactant gas, which is the second gas. Examples of such catalysts and gases containing carbon include pyridine gas, as well as cyclic amine gases such as aminopyridine (C5H6N2, pKa = 6.89) gas, picoline (C6H7N, pKa = 6.07) gas, lutidine (C7H9N, pKa = 6.96) gas, piperazine (C4H10N2, pKa = 9.80) gas, and piperidine (C5H11N, pKa = 11.12) gas; triethylamine ((C2H5)3N, abbreviation: TEA, pKa = 10.7) gas, Chain amine gases such as diethylamine ((C2H5)2NH, abbreviation: DEA, pKa = 10.9) gas, monoethylamine ((C2H5)NH2, abbreviation: MEA, pKa = 10.6) gas, trimethylamine ((CH3)3N, abbreviation: TMA, pKa = 9.8) gas, dimethylamine ((CH3)2NH, abbreviation: DMA, pKa = 10.8) gas, and monomethylamine ((CH3)NH2, abbreviation: MMA, pKa = 10.6) gas can be used.

[0130] In the above embodiment, a film forming process on the wafer 200 is taken as an example of the substrate processing step, but the present invention is not limited to this and can be applied to other processes that require gas supply and exhaust. Examples of other processes include a diffusion process, an oxidation process, a nitridation process, an oxynitridation process, a reduction process, an oxidation-reduction process, an etching process, and a heating process.

[0131] In the above embodiment, a batch-type substrate processing apparatus that processes multiple substrates at a time is taken as an example, but the present invention is not limited thereto, and can be suitably applied to, for example, a single-wafer type substrate processing apparatus that processes one or several substrates at a time. Furthermore, in the above embodiment, a substrate processing apparatus having a hot-wall type processing furnace is taken as an example, but the present invention is not limited thereto, and can be suitably applied to, for example, a substrate processing apparatus having a cold-wall type processing furnace. [Explanation of symbols]

[0132] 121 Controller (control unit) 200 wafers (substrates) 201 Processing Room 232a, 232b Gas supply pipe 233 Bypass Line 231a, 231b Exhaust pipe 244a, 244b APC valve 244c, 244d valve 246a, 246b Vacuum pump

Claims

1. a first gas supply line that supplies a first gas to the substrate in the processing chamber; a first exhaust line connected to a first pump and configured to exhaust the first gas supplied to the substrate; a first valve provided in the first exhaust line; a second gas supply line that supplies a second gas to the substrate in the processing chamber; a second exhaust line connected to a second pump and configured to exhaust the second gas supplied to the substrate; a second valve provided in the second exhaust line; a control unit capable of controlling the first valve and the second valve to perform a first line change process of exhausting the first gas supplied to the substrate toward the second pump through the second exhaust line when it is detected that the first exhaust line has transitioned to a predetermined state; A substrate processing apparatus comprising:

2. a bypass line connected to the first exhaust line via a third valve and connected to the second exhaust line via a fourth valve; The control unit is configured to be capable of controlling the third valve and the fourth valve so as to perform a second line change process for exhausting the first gas in the first exhaust line toward the second pump through the bypass line and the second exhaust line when it detects that the first exhaust line has transitioned to a predetermined state. The substrate processing apparatus according to claim 1 .

3. The control unit is configured to be capable of controlling each of the first valve to the fourth valve so as to perform the first line change process while the substrate is being processed in the processing chamber and to perform the second line change process after the first line change process. The substrate processing apparatus according to claim 2 .

4. The control unit is configured to be capable of controlling the third valve and the fourth valve so as to perform a third line change process in which, when processing of the substrate is not being performed in the processing chamber, the third valve and the fourth valve are opened to exhaust an atmosphere in the first exhaust line from the second exhaust line via the bypass line. The substrate processing apparatus according to claim 2 .

5. The control unit is configured to be capable of controlling the first valve and the second valve so as to perform the third line change process in a state in which both the first valve and the second valve are substantially closed. The substrate processing apparatus according to claim 4 .

6. an inert gas supply line for supplying an inert gas into the processing chamber; The control unit is configured to be capable of determining whether the first exhaust line has transitioned to a predetermined state by detecting a pressure state in the first exhaust line when the inert gas is supplied from the inert gas supply line into the processing chamber and exhausted from the first exhaust line. The substrate processing apparatus according to claim 1 .

7. The control unit is configured to be able to determine whether or not the first exhaust line has transitioned to a predetermined state before the first gas is supplied. The substrate processing apparatus according to claim 1 .

8. The control unit is configured to be able to determine whether or not the first exhaust line has transitioned to a predetermined state between the supply of the first gas and the supply of the second gas. The substrate processing apparatus according to claim 1 .

9. The control unit is configured to be able to determine whether or not the first exhaust line has transitioned to a predetermined state after the second gas is supplied. The substrate processing apparatus according to claim 1 .

10. The control unit is configured to be able to issue an alarm in response to detection of a transition of the first exhaust line to a predetermined state. The substrate processing apparatus according to claim 1 .

11. The control unit is configured to be able to continue processing the substrate in the processing chamber until the processing is completed after the alarm is issued. The substrate processing apparatus according to claim 10 .

12. The control unit is configured to be able to set a state in which a next substrate processing is not started after processing of the substrate in the processing chamber is completed. The substrate processing apparatus according to claim 10 or 11.

13. The control unit is configured to be capable of transmitting either or both of information on the alarm notification and information on the substrate processed in a state in which the alarm notification has been issued to a host device. The substrate processing apparatus according to claim 10 .

14. The first gas is a gas containing a main element constituting a film to be formed on the substrate. The substrate processing apparatus according to claim 1 .

15. The first gas is a silicon-containing gas. The substrate processing apparatus according to claim 1 .

16. The first gas is a halosilane gas. The substrate processing apparatus according to claim 1 .

17. The second gas is a gas that does not contain a main element that constitutes a film to be formed on the substrate. The substrate processing apparatus according to claim 1 .

18. The second gas includes at least one of a carbon-containing gas, an oxygen-containing gas, and a nitrogen- and hydrogen-containing gas. The substrate processing apparatus according to claim 1 .

19. The second gas includes any of a carbon-containing gas, an oxygen-containing gas, and a nitrogen- and hydrogen-containing gas. The substrate processing apparatus according to claim 1 .

20. The control unit is configured to be capable of controlling the first gas supply line and the second gas supply line so as to intermittently and non-simultaneously supply at least one of a silicon-containing gas, a carbon-containing gas, an oxygen-containing gas, and a nitrogen- and hydrogen-containing gas into the processing chamber. The substrate processing apparatus according to claim 1 .

21. The control unit is configured to be capable of controlling the first gas supply line and the second gas supply line so as to intermittently and non-simultaneously supply any of a silicon-containing gas, a carbon-containing gas, an oxygen-containing gas, and a nitrogen- and hydrogen-containing gas into the processing chamber. The substrate processing apparatus according to claim 1 .

22. supplying a first gas from a first gas supply line to the substrate in the processing chamber; exhausting the first gas supplied to the substrate through a first exhaust line connected to a first pump; supplying a second gas from a second gas supply line to the substrate in the processing chamber; exhausting the second gas supplied to the substrate through a second exhaust line connected to a second pump; when it is detected that the first exhaust line has transitioned to a predetermined state, controlling a first valve provided in the first exhaust line and a second valve provided in the second exhaust line so as to exhaust the first gas supplied to the substrate toward the second pump via the second exhaust line; A substrate processing method comprising the steps of:

23. supplying a first gas from a first gas supply line to the substrate in the processing chamber; exhausting the first gas supplied to the substrate through a first exhaust line connected to a first pump; supplying a second gas from a second gas supply line to the substrate in the processing chamber; exhausting the second gas supplied to the substrate through a second exhaust line connected to a second pump; when it is detected that the first exhaust line has transitioned to a predetermined state, controlling a first valve provided in the first exhaust line and a second valve provided in the second exhaust line so as to exhaust the first gas supplied to the substrate toward the second pump via the second exhaust line; A method for manufacturing a semiconductor device having the above structure.

24. supplying a first gas from a first gas supply line to the substrate in the processing chamber; exhausting the first gas supplied to the substrate through a first exhaust line connected to a first pump; supplying a second gas to the substrate in the processing chamber through a second gas supply line; exhausting the second gas supplied to the substrate through a second exhaust line connected to a second pump; when it is detected that the first exhaust line has transitioned to a predetermined state, controlling a first valve provided in the first exhaust line and a second valve provided in the second exhaust line so as to exhaust the first gas supplied to the substrate toward the second pump via the second exhaust line; A program for causing a computer to execute the above in a substrate processing apparatus.

25. An exhaust system including a substrate processing apparatus, a first pump, and a second pump, The substrate processing apparatus includes: a first gas supply line that supplies a first gas to the substrate in the processing chamber; a first exhaust line connected to the first pump and configured to exhaust the first gas supplied to the substrate; a first valve provided in the first exhaust line; a second gas supply line that supplies a second gas to the substrate in the processing chamber; a second exhaust line connected to the second pump and configured to exhaust the second gas supplied to the substrate; a second valve provided in the second exhaust line; a control unit capable of controlling the first valve and the second valve to perform a first line change process of exhausting the first gas supplied to the substrate toward the second pump through the second exhaust line when it is detected that the first exhaust line has transitioned to a predetermined state; An exhaust system having

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