Substrate processing methods, semiconductor device manufacturing methods, processes, and substrate processing apparatus

Abstract

The present invention addresses the problem of providing a technique for improving the stepped coverage of a film formed on a substrate. The solution of the present invention includes a step of forming a film on a substrate by performing a first cycle a predetermined number of times. The first cycle comprises (a) supplying a first processing gas to the substrate and (b) supplying a second processing gas to the substrate. In (a), the following steps are performed sequentially: (a-1) opening a first storage compartment filled with the first processing gas and supplying the first processing gas released from the first storage compartment to the substrate via a first supply port; (a-2) venting the processing space of the substrate while the supply of the first processing gas to the substrate is stopped; and (a-3) opening a second storage compartment filled with the first processing gas and supplying the first processing gas released from the second storage compartment to the substrate via a second supply port different from the first supply port.

Description

[Technical Field]

[0001] This invention relates to a substrate processing method, a method for manufacturing a semiconductor device, a process, and a substrate processing apparatus. [Previous Technology]

[0002] As a step in the substrate processing step (the manufacturing step of a semiconductor device), there is a process of forming a film on the substrate (see, for example, Patent Document 1). [Prior Art Documents] [Patent Documents]

[0003] Patent Document 1: Japanese Patent Application Publication No. 2022-052622 [Summary of the Invention]

[0004] (Problem to be Solved by the Invention) The present invention provides a technique for improving the step coverage of a film formed on a substrate. (Technical Means for Solving the Problem)

[0005] According to one aspect of the present invention, a technique is provided that includes the step of forming a film on a substrate by performing a first cycle a predetermined number of times, wherein the first cycle includes (a) supplying a first processing gas to the substrate and (b) supplying a second processing gas to the substrate; in (a), the following steps are performed sequentially: (a-1) opening a first storage compartment filled with the first processing gas and supplying the first processing gas released from the first storage compartment to the substrate through a first supply port; (a-2) venting the processing space of the substrate while the supply of the first processing gas to the substrate is stopped; and (a-3) opening a second storage compartment filled with the first processing gas and supplying the first processing gas released from the second storage compartment to the substrate through a second supply port different from the first supply port. (Effects compared to prior art)

[0006] According to the present invention, the step coverage of the film formed on the substrate can be improved.

Implementation Method

[0008] <One Embodiment of the Invention> Hereinafter, one embodiment of the invention will be described with reference to FIGS. 1 to 4. The drawings used in the following description are schematic, and the dimensional relationships and ratios of the components in the drawings may not be consistent with the actual situation. In addition, the dimensional relationships and ratios of the components may not be consistent among the multiple drawings.

[0009] (1) The structure of the substrate processing apparatus is shown in FIG1. ​​The processing furnace 202 has a heater 207 as a temperature regulator (heating unit). The heater 207 is cylindrical and is vertically positioned by being supported by a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that uses heat to activate (excite) the gas.

[0010] Inside the heater 207, a reaction tube 203 is arranged 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 into a cylindrical shape that is closed at the top and open at the bottom. Below the reaction tube 203, a manifold 209 is arranged concentrically with the reaction tube 203. The upper end of the manifold 209 engages with the lower end of the reaction tube 203, thus supporting the reaction tube 203. An O-ring 220a, serving as a sealing component, is provided between the manifold 209 and the reaction tube 203. The reaction tube 203 is also vertically oriented, just like the heater 207. The processing container (reaction container) is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed in the hollow part of the cylindrical part of the processing container. The processing chamber 201 is configured to accommodate a wafer 200, which serves as a substrate. The wafer 200 is processed in the processing chamber 201.

[0011] Inside the processing chamber 201, nozzles 249a to 249c, serving as first to third supply sections, are respectively provided through the side wall of the manifold 209. These nozzles are also referred to as the first to third nozzles. The nozzles 249a to 249c are made of, for example, heat-resistant materials such as quartz or SiC. Each of the nozzles 249a to 249c is connected to a gas supply pipe 232a to 232c, which serve as the first to third piping. The nozzles 249a to 249c are different nozzles.

[0012] In the gas supply pipe 232a, which serves as the first piping, and the gas supply pipe 232b, which serves as the second piping, mass flow controllers (MFCs) 241a and 241b, which serve as flow controllers (flow control units), valves 243a and 243b, which serve as switching valves, and a first storage unit 240a, a second storage unit 240b, and valves 242a and 242b, configured to temporarily store gas, are sequentially provided from the upstream side of the gas flow. The first storage unit 240a is connected to the gas supply port 250a, which serves as the first supply port, via the gas supply pipe 232a, which serves as the first piping. The second storage unit 240b is connected to the gas supply port 250b, which serves as the second supply port, via the gas supply pipe 232b, which serves as the second piping and is independent of the gas supply pipe 232a. A gas supply pipe 232e is connected downstream of the valve 242a of the gas supply pipe 232a. Gas supply pipes 232d and 232f are connected downstream of valve 242b in gas supply pipe 232b. MFCs 241d to 241f and valves 243d to 243f are sequentially installed on gas supply pipes 232d to 232f, starting from the upstream side of the gas flow.

[0013] The first storage section 240a and the second storage section 240b are respectively constructed from gas tanks with a gas capacity larger than that of ordinary piping, piping with a diameter larger than that of ordinary piping, or spiral piping. The configuration allows for the filling of the first storage section 240a and the second storage section 240b with gas supplied from gas supply pipes 232a and 232b by opening and closing valves 243a and 243b upstream of the first storage section 240a and the second storage section 240b, and the supply of gas filled in the first storage section 240a and the second storage section 240b to the processing chamber 201. The gas conductance between the first storage section 240a and the processing chamber 201 is preferably configured to be, for example, 1.5 × 10⁻³ m³ / s or higher. Furthermore, considering the ratio of the volume of the processing chamber 201 to the volume of the first storage section 240a, when the volume of the processing chamber 201 is 100L, the volume of the first storage section 240a is preferably 100 to 3000cc, and preferably 1 / 1000 to 30 / 1000 times the volume of the processing chamber 201. The same applies to the second storage section 240b.

[0014] By closing valves 242a and 242b and opening valves 243a and 243b, the gas whose flow rate has been adjusted by MFCs 241a and 241b can be filled into the first storage section 240a and the second storage section 240b, respectively. After a predetermined amount of gas is filled into the first storage section 240a and the second storage section 240b, and the pressure in the first storage section 240a and the second storage section 240b reaches a predetermined pressure, valves 243a and 243b are closed and valves 242a and 242b are opened. This allows the high-pressure gas filled into the first storage section 240a and the second storage section 240b to be supplied into the processing chamber 201 in a short time through gas supply pipes 232a and 232b and nozzles 249a and 249b (flash supply). In addition, valves 243a and 243b can also be opened during flash supply.

[0015] In the gas supply pipe 232c, an MFC 241c and a valve 243c serving as a switching valve are sequentially arranged from the upstream side of the gas flow. A gas supply pipe 232g is connected downstream of the valve 243c in the gas supply pipe 232c. In the gas supply pipe 232g, an MFC 241g and a valve 243g are sequentially arranged from the upstream side of the gas flow.

[0016] As shown in Figure 2, the nozzles 249a to 249c form a ring-shaped space between the inner wall of the reaction tube 203 and the wafer 200 when viewed from above. They are respectively arranged to stand upright along the lower part of the inner wall of the reaction tube 203 upwards and towards the arrangement direction of the wafer 200. That is, the nozzles 249a to 249c are arranged horizontally around the wafer arrangement area on the side of the wafer arrangement area where the wafers 200 are arranged, and are respectively arranged along the wafer arrangement area.

[0017] Nozzle 249c is positioned near the exhaust port 231a, as described later, relative to nozzles 249a and 249b. That is, nozzles 249a and 249b are positioned far from the exhaust port 231a relative to nozzle 249c. Furthermore, when viewed from above, nozzles 249a and 249b are arranged linearly symmetrically with the center of the wafer 200 (in the state where the wafer 200 has been moved into the processing chamber 201), i.e., the straight line passing through the center of the reaction tube 203 and the center of the exhaust port 231a, as the axis of symmetry. Additionally, nozzles 249b and 249c are arranged opposite each other along a straight line, sandwiching the center of the reaction tube 203. That is, nozzle 249b is arranged facing (opposite to) nozzle 249c.

[0018] Gas supply holes 250a-250c, serving as first to third supply ports, are respectively provided on the side surfaces of nozzles 249a-249c, supplying gas from the outer periphery of the wafer 200 into the plane of the wafer 200. The first and third gas supply holes 250a and 250c open towards or near the center of the reaction tube 203, respectively, allowing gas to be supplied towards the wafer 200. The second gas supply hole 250b is configured to supply gas towards the outer edge of the wafer 200 in a direction different from the direction towards the center of the wafer 200; more specifically, relative to the direction towards the center of the wafer 200. A plurality of gas supply holes 250a-250c are provided from the bottom to the top of the reaction tube 203.

[0019] Nozzles 249a and 249b may also be arranged in a more intimate manner, sandwiching a straight line passing through the center of the reaction tube 203 and the center of the exhaust port 231a. Furthermore, gas supply holes 250a and 250b may also be able to open in a direction parallel to the straight line passing through the center of the reaction tube 203 and the center of the exhaust port 231a.

[0020] Furthermore, the gas supply holes 250a to 250c are not limited to being circular or elliptical openings, but may also be other shapes of openings, such as slit-shaped openings extending in a direction perpendicular to the extending direction of the nozzles 249a to 249c (i.e., the plane direction of the wafer 200). Additionally, the gas supply holes 250a to 250c may each be composed of one or more slit-shaped openings provided along the extending direction of the nozzles 249a to 249c.

[0021] A first processing gas is supplied as raw material gas from the gas supply pipe 232a through MFC 241a, valve 243a, first storage unit 240a, valve 242a, and nozzle 249a into the processing chamber 201.

[0022] A first processing gas is supplied as raw material gas from the gas supply pipe 232b through MFC 241b, valve 243b, second storage section 240b, valve 242b, and nozzle 249b into the processing chamber 201.

[0023] A second processing gas is supplied as a reaction gas from the gas supply pipe 232c via MFC 241c, valve 243c, and nozzle 249c into the processing chamber 201.

[0024] Modified gas is supplied to the processing chamber 201 from the gas supply pipe 232d via MFC 241d, valve 243d, and nozzle 249d.

[0025] Inert gas is supplied to the processing chamber 201 from gas supply pipes 232e-232g via MFC 241e-241g, valves 243e-243g, gas supply pipes 232a-232c, and nozzles 249a-249c. The inert gas functions as a purge gas, carrier gas, and dilution gas.

[0026] The first gas supply system (first processing gas supply system) is mainly composed of gas supply pipe 232a, MFC 241a, valves 243a and 242a, and the first storage unit 240a. The second gas supply system (first processing gas supply system) is mainly composed of gas supply pipe 232b, MFC 241b, valves 243b and 242b, and the second storage unit 240b. The third gas supply system (second processing gas supply system) is mainly composed of gas supply pipe 232c, MFC 241c, and valve 243c. The fourth gas supply system (refining gas supply system) is mainly composed of gas supply pipe 232d, MFC 241d, and valve 243d. The inert gas supply system is mainly composed of gas supply pipes 232e-232g, MFC 241e-241g, and valves 243e-243g. Furthermore, nozzles connected to the gas supply pipes constituting the various supply systems described above may also be included in the supply system.

[0027] An exhaust port 231a for venting the environment inside the processing chamber 201 is provided below the side wall of the reaction tube 203. As shown in FIG2, when viewed from above, the exhaust port 231a is positioned opposite the nozzles 249a and 249b (gas supply holes 250a and 250b) across the wafer 200. The exhaust port 231a may also be provided along the side wall of the reaction tube 203 from bottom to top, that is, along the wafer arrangement area. An exhaust pipe 231, which serves as an exhaust path, is connected to the exhaust port 231a. The exhaust pipe 231 is connected to a vacuum pump 246, which serves as a vacuum venting device, via a pressure sensor 245, which serves as a pressure detector (pressure detection unit) for detecting the pressure inside the processing chamber 201, and an APC (Auto Pressure Controller) valve 244, which serves as a pressure regulator (pressure adjustment unit). The APC valve 244, serving as the exhaust valve, is configured to allow for vacuum exhaust and cessation of vacuum exhaust within the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is running. Furthermore, while the vacuum pump 246 is running, the valve opening is adjusted based on pressure information detected by the pressure sensor 245, thereby regulating the pressure within the processing chamber 201. The exhaust system mainly consists of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. It is also possible to include the vacuum pump 246 within the exhaust system.

[0028] A sealing cover 219, serving as a furnace opening cover, is provided below the manifold 209 to airtightly seal the lower opening of the manifold 209. An O-ring 220b, serving as a sealing component, is provided on the upper surface of the sealing cover 219, abutting against the lower end of the manifold 209. A rotation mechanism 267, which rotates the crystal boat 217 (described later), is provided below the sealing cover 219. The rotation shaft 255 of the rotation mechanism 267 passes through the sealing cover 219 and is connected to the crystal boat 217. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the crystal boat 217. The sealing cover 219 is configured to be raised and lowered vertically by a crystal boat elevator 115, which is a lifting mechanism located outside the reaction tube 203. The crystal boat elevator 115 is configured as a conveying device (conveyor) that moves the wafer 200 in and out of the processing chamber 201 by raising and lowering the sealing cover 219.

[0029] Below the manifold 209, a gate 219s, serving as a furnace opening cover, is provided. This gate can airtightly seal the lower opening of the manifold 209 when the sealing cover 219 is lowered and the crystal boat 217 is removed from the processing chamber 201. An O-ring 220c, serving as a sealing component, is provided on the upper surface of the gate 219s, abutting against the lower end of the manifold 209. The opening and closing action (lifting, rotating, etc.) of the gate 219s is controlled by a gate opening and closing mechanism 115s.

[0030] The crystal boat 217, which serves as a substrate support, is configured to support multiple wafers 200, for example 25 to 200, arranged horizontally and aligned with each other in a vertical direction in multiple layers, i.e., arranged at intervals. The crystal boat 217 is made of heat-resistant materials such as quartz or SiC. Heat insulation plates 218 are supported in multiple layers at the bottom of the crystal boat 217.

[0031] A temperature sensor 263, serving as a temperature detector, is provided inside the reaction tube 203. The energizing level of the heater 207 is adjusted based on the temperature information detected by the temperature sensor 263, so that the temperature inside the processing chamber 201 becomes the desired temperature distribution. The temperature sensor 263 is provided along the inner wall of the reaction tube 203.

[0032] As shown in FIG3, the controller 121, which serves as the control unit (control unit), is configured as a computer equipped with a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, a memory device 121c, and an I / O port 121d. The RAM 121b, memory 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. In addition, the controller 121 is configured to be connected to an external memory device 123. Furthermore, the board processing apparatus may be configured to have one control unit or multiple control units. That is, control for performing the processing flow described later can be performed using one control unit or multiple control units. Furthermore, the multiple control units can be configured as a control system interconnected by wired or wireless communication networks, or the entire control system can be used to control the processing flow described later. In this specification, the term "control unit" refers not only to a single control unit, but also to a system comprising multiple control units or a control system composed of multiple control units.

[0033] The memory device 121c is composed of, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. The memory device 121c records and stores in a readable manner a control program that controls the operation of the board processing device, a process recipe that records the board processing procedures and conditions described later, etc. The process recipe is composed of combinations that allow the board processing device to execute the various procedures in the board processing described later and obtain a predetermined result via the controller 121, and functions as a program. Hereinafter, the process recipe, control program, etc., will also be collectively referred to as a program. Furthermore, the process recipe will be simply referred to as a recipe. When the term "program" is used in this specification, there may be cases where only a recipe is included, cases where only a control program is included, or cases where both are included. The RAM 121b is configured as a memory area (working area) that temporarily holds programs, data, etc., read by the CPU 121a.

[0034] I / O port 121d is connected to the above-mentioned MFC 241a~241g, valves 243a~243g, 242a, 242b, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotating mechanism 267, crystal boat elevator 115, gate switching mechanism 115s, etc.

[0035] The CPU 121a is configured to read and execute a control program from the memory device 121c, and to read a recipe from the memory device 121c based on inputs of operation commands from the input / output device 122. The CPU 121a is configured to control, according to the contents of the read recipe, various flow rate adjustment actions of substances (various gases) performed by the MFCs 241a~241g, the opening and closing actions of valves 243a~243g, 242a, 242b, the opening and closing actions of the APC valve 244, the pressure adjustment actions of the APC valve 244 based on the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment actions of the heater 207 based on the temperature sensor 263, the rotation and rotation speed adjustment actions of the crystal boat 217 performed by the rotating mechanism 267, the lifting and lowering actions of the crystal boat 217 performed by the crystal boat elevator 115, and the opening and closing actions of the gate 219s performed by the gate switching mechanism 115s.

[0036] The controller 121 may be configured to install the aforementioned program, which is recorded and stored in the external memory device 123, onto a computer. The external memory device 123 may include, for example, magnetic disks such as HDDs, optical disks such as CDs, optical discs such as MO drives, USB memory, semiconductor memory such as SSDs, etc. The memory device 121c and the external memory device 123 constitute a computer-readable recording medium. Hereinafter, these will also be collectively referred to as recording media. When the term "recording media" is used in this specification, sometimes only the memory device 121c is included, sometimes only the external memory device 123 is included, or sometimes both are included. Furthermore, the program may be provided to the computer using communication means such as the Internet or dedicated lines, without using the external memory device 123.

[0037] (2) Substrate processing step Using the above-described substrate processing apparatus as a step in the manufacturing process of a semiconductor device, FIG4 is mainly used to describe a process example of a method for processing a substrate, namely, a process example of forming a film on a wafer 200 of a substrate with three-dimensional grooves, trenches, holes and other recesses formed on its surface. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

[0038] In the processing flow of this sample, there is a step of forming a film on the wafer 200 by performing a first cycle a predetermined number of times (n times, where n is an integer of 1 or 2 or more). The first cycle is performed non-simultaneously: (a) step A of supplying a first processing gas to the wafer 200, and (b) step B of supplying a second processing gas to the wafer 200. In step A, the following are performed sequentially: (a-1) step a1 of opening the first storage section 240a filled with the first processing gas and supplying the first processing gas released from the first storage section 240a to the wafer 200 through the gas supply hole 250a. (a-2) Step a2, which involves venting the processing space of wafer 200 while the supply of the first processing gas to wafer 200 has been stopped, and (a-3) Step a3, which involves opening the second storage section 240b filled with the first processing gas and supplying the first processing gas released from the second storage section 240b to wafer 200 through a gas supply hole 250b that is different from the gas supply hole 250a.

[0039] In this sample, as shown in FIG4, exhaust can also be performed in the processing chamber 201 after the supply of the first processing gas in step A and after the supply of the second processing gas in step B. The exhaust process will be explained below.

[0040] In this specification, for convenience, the above processing flow is sometimes represented as follows. The same expression is also used in the following descriptions of variations or other forms.

[0041] {(First processed gas → Exhaust → First processed gas → Exhaust) →(Second processed gas → Exhaust)}×n

[0042] When the term "wafer" is used in this specification, it sometimes refers to the wafer itself, and sometimes refers to a laminate of the wafer and a predetermined layer or film formed on its surface. When the term "surface of the wafer" is used in this specification, it sometimes refers to the surface of the wafer itself, and sometimes refers to the surface of a predetermined layer or the like formed on the wafer. When described in this specification as "forming a predetermined layer on the wafer," it sometimes means forming the predetermined layer directly on the surface of the wafer itself, and sometimes means forming the predetermined layer on top of a layer or the like formed on the wafer. When the term "substrate" is used in this specification, it is synonymous with the use of the term "wafer."

[0043] The term "layer" as used in this specification includes at least one of continuous layers and discontinuous layers. For example, the first to third layers described below may include continuous layers, discontinuous layers, or both.

[0044] In this specification, when describing the adsorption and reaction of the first processing gas and the second processing gas relative to the surface of the wafer 200, it includes not only the adsorption and reaction of the wafer surface in an undecomposed state, but also the adsorption and reaction of intermediates generated by decomposition and ligand detachment on the surface of the wafer 200.

[0045] (Wafer Filling and Ship Loading) After a plurality of wafers 200 are loaded into the ship 217 (wafer filling), the gate 219s is moved by the gate opening mechanism 115s, opening the lower end of the manifold 209 (gate opening). Then, as shown in FIG1, the ship 217 supporting the plurality of wafers 200 is lifted by the ship lift 115 and moved into the processing chamber 201 (ship loading). In this state, the sealing cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0046] (Pressure and Temperature Adjustment) After the wafer boat is loaded, vacuum pump 246 is used to exhaust the vacuum (pressure reduction exhaust) to bring the pressure (vacuum level) in the processing chamber 201, i.e., the space where the wafer 200 exists (i.e., the processing space), to the desired pressure. At this time, the pressure in the processing chamber 201 is measured by pressure sensor 245, and the APC valve 244 is controlled based on the measured pressure information (pressure adjustment). In addition, the wafer 200 in the processing chamber 201 is heated by heater 207 to bring it to the desired processing temperature. At this time, the energization level of heater 207 is controlled based on the temperature information detected by temperature sensor 263 (temperature adjustment) to bring the processing chamber 201 to the desired temperature distribution. In addition, the wafer 200 is rotated by rotation mechanism 267. The exhaust in the processing chamber 201, the heating of the wafer 200, and the rotation are all carried out continuously at least until the processing of the wafer 200 is completed.

[0047] (Film forming treatment) After that, proceed with the following steps A and B in sequence.

[0048] [Step A] In this step, step a1 of supplying a first processing gas to the wafer 200 in the processing chamber 201, step a2 of venting the processing chamber 201, and step a3 of supplying the first processing gas to the wafer 200 in the processing chamber 201 are performed sequentially. Here, "venting" refers to at least one of purging and vacuum venting. In this example, as an example, the case where purging and vacuum venting are performed sequentially when venting the processing chamber 201 is described.

[0049] Before performing step a1, valve 242a is closed, and valve 243a is opened to allow the first processing gas to flow into the gas supply pipe 232a. The flow rate of the first processing gas is adjusted by MFC 241a and supplied to the first storage section 240a. In this way, the first processing gas is pressurized to the filling pressure and filled into the first storage section 240a. After a predetermined amount of the first processing gas has been filled into the first storage section 240a, valve 243a is closed to maintain the state where the first processing gas is filled into the first storage section 240a.

[0050] (i) Step a1 In this step, a first processing gas is supplied to the wafer 200 in the processing chamber 201.

[0051] Specifically, valve 242a is opened, allowing the high-pressure first processing gas filled in the first storage section 240a to flow into the depressurized processing chamber 201 in one go. This supplies the wafer 200 with the first processing gas in one go (first flash supply of the first processing gas). At this time, valve 243a is opened. Valves 243e-243g can also be opened at this time, supplying inert gas into the processing chamber 201 via nozzles 249a-249c, respectively. At this time, the APC valve 244 is substantially fully open. Valve 243a may also remain closed at this time.

[0052] The processing conditions for supplying the first processing gas in step a1 can be exemplified as follows: Processing temperature: 250~900℃, preferably 650~850℃; Processing pressure: 1~2666 Pa, preferably 1~1333 Pa; First processing gas filling pressure: 60~1500 Torr, preferably 200~1200 Torr; First processing gas supply amount: 50~3000cc, preferably 100~2000cc; First processing gas supply time: 0.1~20 seconds, preferably 0.5~5 seconds; Inert gas supply flow rate (per gas supply pipe): 0~20slm.

[0053] The expression "250~900℃" in this specification refers to the fact that the lower and upper limits are included within this range. Therefore, for example, "250~900℃" means "above 250℃ and below 900℃". The same applies to other numerical ranges. In addition, the processing temperature in this specification refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201, and the processing pressure refers to the pressure inside the processing chamber 201. In addition, the processing time refers to the duration of the processing. In addition, when the supply flow rate includes 0slm, 0slm means that the substance (gas) is not supplied. The same applies to the following description.

[0054] Under the above processing conditions, by supplying a first processing gas containing predetermined elements (i.e. a raw material gas containing predetermined elements) to the wafer 200, the first processing gas can be adsorbed onto the surface of the wafer 200 to form a first layer containing predetermined elements.

[0055] When the predetermined element is silicon (Si), the first processing gas can be a silane-based gas. As a silane-based gas, for example, a gas containing Si and a halogen, i.e., a halosilane-based gas, can be used. As a halogen, at least one element selected from chlorine (Cl), fluorine (F), bromine (Br), and iodine (I) can be used.

[0056] As the first processing gas, a chlorosilane gas such as tetrachlorosilane (SiCl 4), monochlorosilane (SiH 3Cl), dichlorosilane (SiH 2Cl 2), or trichlorosilane (SiHCl 3) can be used, and the gas does not contain Si bonds between each other (i.e., bonds between predetermined elements) in one molecule. As the first processing gas, in addition to chlorosilane-based gases, for example, fluorosilane-based gases such as tetrafluorosilane (SiF4) gas and difluorosilane (SiH2F2) gas, bromosilane-based gases such as tetrabromosilane (SiBr4) gas and dibromosilane (SiH2Br2) gas, iodine-based gases such as tetraiodosilane (SiI4) gas and diiodosilane (SiH2I2) gas can also be used, provided that one molecule does not contain bonds between Si (i.e., bonds between predetermined elements).

[0057] In addition, as the first processing gas, gases such as hexachlorosilane (Si 2Cl 6), octachloropropane (Si 3Cl 8), monochlorosilane (Si 2H 5Cl), dichlorosilane (Si 2H 4Cl 2), trichlorosilane (Si 2H 3Cl 3), tetrachlorosilane (Si 2H 2Cl 4), monochloropropane (Si 3H 5Cl), and dichloropropane (Si 3H 4Cl 2) can be used, and these gases contain bonds between Si elements (i.e., bonds between predetermined elements) in one molecule.

[0058] In addition, as the first processing gas, besides the above, for example, a gas containing Si and an amino group in one molecule, i.e., an aminosilane gas, can also be used. An amino group refers to a monovalent functional group obtained by removing hydrogen (H) from ammonia, a primary amine, or a secondary amine, and can be represented as -NH₂, -NHR, or -NR₂. Furthermore, R represents an alkyl group, and the two Rs in -NR₂ can be the same or different.

[0059] As the first processing gas, for example, tetra(dimethylamino)silane (Si[N(CH 3) 2] 4 gas, tri(dimethylamino)silane (Si[N(CH 3) 2] 3H) gas, bis(diethylamino)silane (Si[N(C 2H) 2] 2H) gas, bis(tert-butylamino)silane (SiH 2[NH(C 4H 9)] 2) gas, (diisopropylamino)silane (SiH 3[N(C 3H 7) 2]) gas, and other aminosilane gases can also be used.

[0060] One or more of these can be used as the first processing gas. This point is also the same in step a3 described later.

[0061] As the inert gas, nitrogen (N2), argon (Ar), helium (He), neon (Ne), xenon (Xe), and other inert gases can be used. More than one of these can be used as the inert gas. This also applies to the steps described later.

[0062] (ii) Step a2 After forming the first layer on the surface of the wafer 200, valves 243a and 242a are closed to stop the supply of the first processing gas to the processing chamber 201. Then, valves 243e to 243g are opened to supply inert gas to the processing chamber 201 through nozzles 249a to 249c. The inert gas system supplied from nozzles 249a to 249c functions as a purge gas, thereby purging the processing chamber 201, which is the space where the wafer 200 is located, i.e., the space where the wafer 200 is processed (processing space). Afterward, valves 243e to 243g are closed to stop the supply of inert gas to the processing chamber 201. Then, a vacuum is vented from the processing chamber 201 to remove gaseous substances and the like remaining in the processing chamber 201.

[0063] Here, "purging" means removing intermediates of the first and second processed gases, other byproducts, etc., present in the processing chamber 201 by supplying inert gas into the processing chamber 201. "Vacuum venting" means removing intermediates of the first and second processed gases, etc., present in the processing chamber 201 without supplying inert gas into the processing chamber 201. In addition, "no inert gas supply" in "vacuum venting" means that no purging gas is supplied, but carrier gas or a small amount of inert gas can also be supplied. In addition, "intermediates of the first and second processed gases" refers to substances that are mainly thermally decomposed in the first and second processed gases in the processing chamber 201.

[0064] During step a2, valve 242b is closed, and valve 243b is opened to allow the first processing gas to flow into gas supply pipe 232b. The flow rate of the first processing gas is adjusted by MFC 241b and supplied to the second storage section 240b. This allows the first processing gas to be pressurized to the filling pressure and filled into the second storage section 240b (canister filling). After a predetermined amount of the first processing gas has been filled into the second storage section 240b, valve 243b is closed, maintaining the second storage section 240b filled with the first processing gas. This canister filling can also be performed during step a1 or approximately simultaneously with stopping the release of the first processing gas from the first storage section 240a in step a1.

[0065] (iii) Step a3 In this step, a first processing gas is supplied to the wafer 200 in the processing chamber 201.

[0066] Specifically, valve 242b is opened, allowing the high-pressure first processing gas filled in the second storage section 240b to flow into the depressurized processing chamber 201 in one go. This supplies the wafer 200 with the first processing gas in one go (second flash supply of the first processing gas). At this time, valve 243a is opened. Also at this time, valves 243e to 243g can be opened to supply inert gas into the processing chamber 201 via nozzles 249a to 249c, respectively.

[0067] The processing conditions for supplying the first processing gas in this step (step a3) may be the same as those for supplying the first processing gas in step a1. However, the processing conditions for step a1 may also be different from those in this step in order to adjust the distribution of film thickness in the plane of wafer 200, etc.

[0068] By supplying a first processing gas to the wafer 200 under the above processing conditions, the first processing gas can be adsorbed onto the surface of the wafer 200 on which the first layer is formed, further forming a second layer containing the predetermined element. The second layer is mainly formed in the region on the surface of the wafer 200 where the first layer is not formed (e.g., adsorption sites on the surface of the wafer 200). However, the second layer can also be formed on the first layer. Here, the first layer and the second layer containing the predetermined element are described separately, but the first layer and the second layer can also be understood as a single layer containing the predetermined element (a layer containing the predetermined element).

[0069] After the second layer is formed on the surface of wafer 200, valves 243b and 242b are closed to stop the supply of the first processing gas to the processing chamber 201. Then, the processing chamber 201 is purged using the same procedures and conditions as in step a2. Afterward, vacuum exhaust is performed on the processing chamber 201 using the same procedures and conditions as in step a2.

[0070] [Step B] After step A is completed, a second processing gas is supplied to the wafer 200 in the processing chamber 201.

[0071] Specifically, valve 243c is opened to allow the second processing gas to flow into gas supply pipe 232c. The second processing gas, with its flow rate adjusted by MFC 241c, is supplied to processing chamber 201 via nozzle 249c and exhausted from exhaust port 231a. At this time, the second processing gas is supplied to wafer 200 (second processing gas supply). At this time, valves 243e-243g can also be opened to supply inert gas into processing chamber 201 via nozzles 249a-249c, respectively. At this time, the valve opening of APC valve 244 is reduced from the fully open state. Specifically, the valve opening of APC valve 244 is adjusted to a state between fully open and fully closed, and the pressure in processing chamber 201 is adjusted to a predetermined processing pressure.

[0072] The processing conditions for supplying the second processing gas in this step can be exemplified as follows: Processing temperature: 250~900℃, preferably 650~850℃; Processing pressure: 10~10000 Pa, preferably 20~5000 Pa; Second processing gas supply flow rate: 0.001~20slm, preferably 1~10slm; Second processing gas supply time: 1~120 seconds, preferably 1~60 seconds; Inert gas supply flow rate (per gas supply pipe): 0~20slm.

[0073] By supplying a second processing gas to the wafer 200 under the above-described processing conditions, at least a portion of the first and second layers formed on the wafer 200 react with the second processing gas and are modified. As a result, a third layer is formed on the wafer 200 as a modified layer of the first and second layers. That is, the second processing gas is a reactive gas that reacts with the first and second layers to be modified into the third layer.

[0074] As the second processing gas, a nitrogen- (N) and hydrogen- (H) gas, which is used as a nitriding gas, can be used, for example. The gas containing N and H is both a N-containing gas and a H-containing gas. It is preferable that the N- and H-containing gas has NH bonds.

[0075] As a second processing gas, for example, hydrogen nitride gases such as ammonia (NH3), diazoxide (N2H2), hydrazine (N2H4), and N3H8 can be used.

[0076] As the second processing gas, in addition to the above, gases containing N, carbon (C), and H may also be used, for example. As gases containing N, C, and H, amine-based gases and organic hydrazine-based gases may be used, for example. A gas containing N, C, and H is a gas containing N, a gas containing C, a gas containing H, and a gas containing both N and C.

[0077] As the second processing gas, for example, ethylamine gases such as monoethylamine (C 2H 5NH 2), diethylamine ((C 2H 5) 2NH), triethylamine ((C 2H 5) 3N), monomethylamine (CH 3NH 2), dimethylamine ((CH 3) 2NH), trimethylamine ((CH 3) 3N), monomethylhydrazine ((CH 3)HN 2H 2), dimethylhydrazine ((CH 3) 2N 2H 2), trimethylhydrazine ((CH 3) 2N 2(CH 3)H) gas, etc., can be used.

[0078] One or more of these may be used as the second processing gas.

[0079] After the third layer is formed on the surface of wafer 200, valve 243c is closed to stop the supply of the second processing gas to the processing chamber 201. Then, the processing chamber 201 is purged using the same procedures and conditions as in step a2. Afterward, the processing chamber 201 is vacuumed using the same procedures and conditions as in step a2.

[0080] [Performance a predetermined number of times] By performing the first cycle of steps A and B sequentially and asynchronously n times (n is an integer of 1 or 2 or more), a film can be formed on the surface of wafer 200. That is, the first cycle in this sample includes cycles of steps A and B respectively. Alternatively, from another viewpoint, in this sample, steps A and B are performed alternately n times. When the predetermined element contained in the first processing gas is, for example, Si, a silicon nitride film (SiN film) containing Si can be formed on the surface of wafer 200. The first cycle described above is preferably repeated multiple times. That is, it is preferable to make the thickness of the third layer formed in each cycle thinner than the desired film thickness, and repeat the above cycle multiple times until the thickness of the film (e.g., SiN film) formed by stacking the third layer is the desired thickness. At this time, in step A, it is preferable to make the amount of the first processing gas pre-filled into the first storage section 240a and the second storage section 240b a fixed amount in each cycle. Furthermore, in the first cycle after the second cycle, it is preferable that the filling of the first processing gas into the first storage unit 240a in step a1 is carried out in parallel with the supply of the second processing gas in step B of the previous cycle.

[0081] (Post-purging and atmospheric pressure restoration) After forming a film of the desired thickness on wafer 200, inert gases as purging gases are supplied into processing chamber 201 through nozzles 249a-249c, and exhaust gases are discharged through exhaust port 231a. This purging process removes residual gases, reaction byproducts, etc., from processing chamber 201 (post-purging). Afterwards, the environment within processing chamber 201 is replaced with inert gas (inert gas replacement), and the pressure within processing chamber 201 is restored to atmospheric pressure (atmospheric pressure restoration).

[0082] (Crystal Boat Unloading and Wafer Release) Subsequently, the sealing cover 219 is lowered by the crystal boat elevator 115, opening the lower end of the manifold 209. Then, the processed wafer 200, supported by the crystal boat 217, is moved from the lower end of the manifold 209 toward the outside of the reaction tube 203 (crystal boat unloading). After the crystal boat is unloaded, the gate 219s is moved, sealing the lower end opening of the manifold 209 (gate closing). After being moved to the outside of the reaction tube 203, the processed wafer 200 is removed from the crystal boat 217 (wafer release).

[0083] (3) Effects of the original sample: Based on the original sample, one or more effects can be obtained as shown below.

[0084] (a) In steps a1 and a3, the first processing gas is pre-filled into the first storage section 240a and the second storage section 240b, respectively, and then pressurized before being supplied to the processing chamber 201. That is, the pressurized first processing gas is supplied to the wafer 200 in the depressurized processing chamber 201 in a short time (flash supply). Accordingly, by increasing the flow rate when supplying the first processing gas to the processing chamber 201, the step coverage of the film formed on the recess of the wafer 200 can be increased.

[0085] In steps a1 and a3, the first processing gas is flash-fed into the processing chamber 201 through gas supply holes 250a and 250b, respectively. Therefore, by using multiple gas supply holes (gas supply holes 250a and 250b) located at different positions along the outer periphery of the wafer 200 (circumferential direction) for flash-fed supply, the controllability of the film thickness distribution within the substrate surface can be improved.

[0086] In step A, the first processing gas is sequentially flash-fed into the processing chamber 201 using different storage units (first storage unit 240a, second storage unit 240b). By sequentially flash-fing the first processing gas, the flash-fing time can be shortened. By shortening the flash-fing time, the retention of the first processing gas or byproducts in the processing chamber 201 can be further reduced. Furthermore, the initial period of high flash-fing flow rate can be utilized. Therefore, by shortening the residence time of the first processing gas in the processing chamber 201, the supply of intermediates and byproducts of the first processing gas to the wafer 200 can be further suppressed. This allows for further improvement in step coverage, improved film thickness distribution on the substrate surface, and reduction in particles.

[0087] In step A, the first processing gas is sequentially flash-supplied into the processing chamber 201 using different storage units (first storage unit 240a, second storage unit 240b). Therefore, even if the number of flash-supplied times is increased, the reduction in production caused by the time for filling the storage unit with the first processing gas (tank filling time) can be minimized, thus achieving both improved step coverage and increased production.

[0088] In step A, during step a2, which is performed between the flash evaporation supply in step a1 and the flash evaporation supply in step a3, exhaust is performed inside the processing chamber 201. This promotes the discharge of the first processing gas and byproducts remaining in the processing chamber 201, thereby achieving further improvement in the stepped coverage, improvement in the film thickness distribution on the substrate surface, and reduction in particles.

[0089] In steps a1 and a3, a first processing gas is flash-supplied into the processing chamber 201 through separate storage units (first storage unit 240a and second storage unit 240b) for different gas supply holes (gas supply holes 250a and 250b). This allows for easy adjustment of the supply amount and flow rate of the first processing gas at each nozzle, further improving the controllability of the film thickness distribution within the substrate surface.

[0090] (b) In steps a1 and a3, the first processing gas is supplied to the wafer 200 while the processing chamber 201 is being vented. In this way, the intermediates of the first processing gas and the byproducts generated by the first processing gas can be continuously discharged from the processing chamber 201, thereby improving the step coverage and the uniformity of the substrate thickness.

[0091] (c) In steps a1 and a3, the opening degree of APC valve 244 in the exhaust state of the processing chamber 201 is made greater than the opening degree of APC valve 244 in the exhaust state of the processing chamber 201 in step B. Therefore, compared to supplying the second processing gas as a reaction gas, the exhaust velocity can be increased, and the intermediates and byproducts of the first processing gas, which is the raw material gas, can be efficiently discharged from the processing chamber 201.

[0092] (d) In step a2, while supplying inert gas to the processing chamber 201, the processing chamber 201 is also vented. In this way, the stagnant gas and by-products in the processing chamber 201 can be discharged more efficiently.

[0093] (e) The first storage unit 240a is connected to the gas supply port 250a via a gas supply pipe 232a, and the second storage unit 240b is connected to the gas supply port 250b via a gas supply pipe 232b that is independent as a second piping and does not share a section with the gas supply pipe 232a. With this structure, there is no need to install other valves for switching between the gas supply port 250a and the gas supply port 250b downstream of the valve 242a on the output side of the first storage unit 240a, thus avoiding the reduction in gas conduction (reduction in flow rate) during flash supply caused by intermediate valves. In addition, it can prevent the first processing gas and the like from being trapped in the piping upstream of the intermediate valves, which would affect the substrate processing.

[0094] (f) Gas supply holes 250a and 250b supply a first processing gas from the outer periphery of the wafer 200 into the surface of the wafer 200, and at least one of the gas supply holes 250a and 250b is configured to supply the first processing gas in a direction different from the direction toward the center of the wafer 200. Accordingly, by adjusting the gas ejection direction of the gas supply holes 250a and 250b respectively, the film thickness distribution in the substrate surface can be easily controlled.

[0095] (g) The above-described effects can be obtained by using the various first processing gases, the various second processing gases, and the various inert gases described above. These effects are particularly pronounced when using a gas containing bonds between predetermined elements as the first processing gas, i.e., when using a gas that is easily decomposed by heat or the like after being supplied to the processing chamber 201. Furthermore, these effects are particularly pronounced when the first processing gas (raw material gas) supplied in the processing chamber 201 decomposes and has a significant impact on the step coverage and the in-plane film thickness distribution of the substrate.

[0096] (4) The processing flow in the original sample can be changed to the following variation. These variations can be combined arbitrarily. Unless otherwise specified, the processing procedures and processing conditions in each step of each variation can be the same as those in each step of the above processing flow.

[0097] (Variation Example 1) As shown in the processing flow in Figure 5 and below, in step A, a second cycle can also be performed a predetermined number of times (m times, where m is an integer greater than or equal to 2). The second cycle is performed sequentially as follows: (a-1) step a1 (first flash evaporation step) in which the first storage section 240a filled with the first processing gas is opened and the first processing gas released from the first storage section 240a is supplied to the wafer 200 through the gas supply hole 250a, and (a-3) step a3 (second flash evaporation step) in which the second storage section 240b filled with the first processing gas is opened and the first processing gas released from the second storage section 240b is supplied to the wafer 200 through the gas supply hole 250b, which is different from the gas supply hole 250a.

[0098] That is, in step A of this variation, step a1 can also be performed after step a3 (steps a1, a3, and a1 can be performed sequentially). In other words, in step A of this variation, steps a1, a3, and a1' can also be performed sequentially. Here, "step a1'" refers to step a1 performed after step a3 in step A.

[0099] Furthermore, in this variation, in step A, exhausting the processing chamber 201 can be performed after step a3 and before the second step a1 (i.e., step a1'), while the supply of the first processing gas to the wafer 200 is stopped. Alternatively, in step A, exhausting the processing chamber 201 can be performed after step a1 and before step a3, while the supply of the first processing gas to the wafer 200 is stopped. That is, in step A, the second cycle of sequentially performing step a1, exhausting, and step a3 can be executed more than twice. Additionally, in step B, exhausting the processing chamber 201 can be performed after the supply of the second processing gas.

[0100] {(First processed gas → Exhaust → First processed gas → Exhaust)×m→(Second processed gas → Exhaust)}×n

[0101] In this variation, the same effect as described above can be obtained. In this variation, by further supplying the first processing gas from the first storage section 240a at least twice, a sufficient amount of the first processing gas can be supplied to the wafer 200. By executing step a1 again, a sufficient amount of the first processing gas can be supplied to the wafer 200. In addition, since the exhaust step is performed while the supply of the first processing gas to the wafer 200 is stopped, the discharge of the first processing gas and by-products remaining in the processing chamber 201 can be promoted, and effects such as further improving the step coverage, improving the in-plane distribution of the substrate, and reducing particles can be obtained. In addition, since the second cycle is performed at least twice, a sufficient amount of the first processing gas can be supplied to the wafer 200. This is particularly suitable for situations where short-time flash evaporation supply is performed.

[0102] (Variation Example 2) As shown in FIG6, in step A, the second cycle of sequentially performing steps a1 and a3 may be executed more than twice, and at least a portion of the execution period of steps a1 and a3 may be repeated. FIG6 illustrates the case of performing the second cycle more than twice. Furthermore, in this variation example, as shown in FIG6, in step A, after the p-th step a3 and before the p+1-th step a1, exhaust may be performed in the processing chamber 201 (p is an integer of 1 or 2 or more) while the supply of the first processing gas to the wafer 200 is stopped.

[0103] In this variation, the same effect as described above can also be obtained. In this variation, by continuously performing flash evaporation in a repetitive manner, a high flow rate can be maintained for a long time. In addition, after step a3, by performing an exhaust step while the first processing gas is stopped from being supplied to the wafer 200, the first processing gas and by-products remaining in the processing chamber 201 can be discharged, thereby further improving the step coverage, improving the in-plane distribution of the substrate, and reducing particles.

[0104] (Variation Example 3) As shown in Figure 7, in step a2, a modified gas that prevents the adsorption of the first processing gas to the surface of the wafer 200 can also be supplied to the wafer 200.

[0105] As a modifying gas, a gas containing at least one of Cl, F, Br, and I, which are halogen elements, can be used. Examples of modifying gases include elemental gases of halogen elements such as fluorine (F₂), chlorine (Cl₂), bromine (Br₂), and iodine (I₂); interhalogen compound gases such as chlorine fluoride (ClF₃), bromine chloride (BrCl), iodine chloride (ICl), iodine fluoride (IF₅), bromine fluoride (BrF₃), and iodine bromide (IBr); hydrogen halide compound gases such as hydrogen chloride (HCl), hydrogen fluoride (HF), hydrogen bromide (HBr), and hydrogen iodide (HI); or gases composed of combinations of these gases. Additionally, free radicals (Cl*, F*, Br*, I*, etc.) containing halogen elements generated by activating such gases using plasma excitation or the like can be used. One or more of these can be used as the modifying gas.

[0106] In step a2, a modifier gas is supplied to the wafer 200 in the processing chamber 201 by means of a modifier gas supply system.

[0107] The processing conditions for supplying the modified gas in this step can be exemplified as follows: Processing temperature: 250~900℃, preferably 650~850℃; Processing pressure: 1~10000 Pa, preferably 10~1333 Pa; Modified gas supply flow rate: 0.01~3 slm, preferably 0.1~1 slm; Modified gas supply time: 1~120 seconds, preferably 5~30 seconds; Inert gas supply flow rate (per gas supply pipe): 0~20 slm.

[0108] By supplying a modifier gas to the wafer 200 under the above processing conditions, the modifier gas can be adsorbed onto adsorption sites present on the surface of the wafer 200 having recesses. By supplying a modifier gas to the wafer 200 under the above processing conditions, the adsorption of the first processing gas supplied in step A onto the wafer 200 is hindered. By controlling the adsorption of the first processing gas onto the surface within the recess by supplying the modifier gas, the step coverage of the film formed in the recess can be improved. For example, by selectively adsorbing the modifier gas onto the upper part of the sidewall surface within the recess, the first processing gas can be preferentially adsorbed onto the lower part and bottom of the sidewall surface within the recess, thereby achieving bottom-up film formation.

[0109] In this variation, the same effect as described above can be obtained. In this variation, the membrane's step coverage can be further improved. In addition, by supplying the modified gas in parallel during the exhaust step, production can be increased.

[0110] Furthermore, in this variation, the example of supplying the modifier gas to the wafer 200 during step a2 has been described, but the modifier gas can also be supplied during periods other than step a2. For example, the modifier gas can be supplied during at least a portion of the periods of steps a1 and a3, in addition to the period of step a2. In this embodiment, the same effect as described above can be obtained. In this embodiment, even if the period of step a2 is short, the time for supplying the modifier gas can still be sufficiently ensured.

[0111] <Other Embodiments of the Invention> The embodiments of the present invention have been specifically described above. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from its spirit.

[0112] Although not specifically described in the above method, the amount of first processing gas supplied to the wafer 200 in step a1 of the (k+1)th cycle of the second cycle can be different from the amount of first processing gas supplied in step a1 of the kth cycle. Here, k is an integer of 1 or 2 or higher. In addition, the amount of first processing gas supplied can be controlled by adjusting the supply time of the first processing gas to the storage section (i.e., the storage amount), the opening time of the first storage section 240a, etc. In this sample, the same effect as in the above sample can also be obtained. In this sample, the film thickness distribution in the substrate surface can also be controlled by adjusting the amount of first processing gas supplied. In particular, by adjusting in the direction of reducing the amount of first processing gas supplied in each cycle, the film thickness distribution in the substrate surface can be adjusted in the direction from concave distribution to convex distribution.

[0113] Although not specifically described in the above-described state, the execution time of at least any one of steps a1 and a3 can be set to make the film thickness distribution in the plane of wafer 200 a desired distribution. The film thickness distribution in the plane of wafer 200 can also be adjusted by adjusting the execution time of at least any one of steps a1 and a3. In this state, the same effect as the above-described state can be obtained. In this state, the film thickness distribution in the plane of wafer 200 can be controlled by further adjusting the supply time of the first processing gas. In particular, by shortening the supply time of the first processing gas in each cycle, the film thickness distribution in the plane of the substrate can be adjusted towards a convex distribution, and by lengthening it, it can be adjusted towards a concave distribution.

[0114] Although not specifically described in the above-described state, in step a1, the release of the first processed gas from the first storage unit 240a can be stopped while the first processed gas remains in the first storage unit 240a. Similarly, in step a3, the release of the first processed gas from the second storage unit 240b can be stopped while the first processed gas remains in the second storage unit 240b. In this state, the same effect as the above-described state can be obtained. In this state, by further stopping the gas release while the gas pressure in the first storage unit 240a and the second storage unit 240b is high, flash evaporation supply can be performed only during the period when the flow rate of the first processed gas is high.

[0115] In the above-described example, the filling of the first processing gas into the first storage unit 240a (can filling) in step A, performed in parallel with step B of the previous cycle, was described as an example. However, the present invention is not limited to this. For example, in the first cycle after the second time, it is preferable to fill the first storage unit 240a with the first processing gas after the release of the first gas in step a1 of the previous cycle has stopped, and during the execution of at least one of steps a2 and a3 (i.e., before step B begins). In this example, the same effect as in the above-described example can also be obtained. In this example, the cycle time can be further shortened, and the production rate can be further increased. In addition, it is preferable that the can filling is performed without discharging the first processing gas in the first storage unit 240a. In this way, the filling time can be shortened. In addition, by not discharging the residual portion, the consumption of the first processing gas can be reduced.

[0116] Unless otherwise specified in the above description, it is preferable that the execution time of step a2 is longer than that of step a1. In this description, the same effect as in the above description can also be obtained. In this description, the time for the exhaust step in the processing chamber 201 can also be sufficiently ensured, further promoting the discharge of the first processing gas and by-products remaining in the processing chamber 201.

[0117] Furthermore, in the above-described embodiment, it was explained that after the supply of the first processing gas in step A and the supply of the second processing gas in step B, the exhaust in the processing chamber 201 was performed sequentially, with purging and vacuum exhaust occurring in sequence. However, the present invention is not limited to the above-described embodiment. For example, in at least one of the exhaust step after the supply of the first processing gas in step A and the exhaust step after the supply of the second processing gas in step B, purging may not be performed, and only vacuum exhaust may be performed. Specifically, for example, in the exhaust step after the supply of the first processing gas in step A, purging may not be performed, and only vacuum exhaust may be performed. In this embodiment, the same effect as in the above-described embodiment can also be obtained.

[0118] Furthermore, in the above-described state sample, a raw material gas containing Si as a predetermined element is used as an example for explanation as the first processing gas. However, the present invention is not limited thereto. For example, the present invention can also be applied in the following situations: using a first processing gas containing metal elements such as aluminum (Al), titanium (Ti), hafnium (Hf), zirconium (Zr), tantalum (Ta), molybdenum (Mo), and tungsten (W) as predetermined elements, through the above-described processing flow, films containing metal elements such as aluminum nitride (AlN film), titanium nitride (TiN film), hafnium nitride (HfN film), zirconium nitride (ZrN film), tantalum nitride (TaN film), molybdenum nitride (MoN) film, tungsten nitride (WN) film, aluminum oxide (AlO film), titanium oxide (TiO film), hafnium oxide (HfO film), zirconium oxide (ZrO film), tantalum oxide (TaO film), molybdenum oxide (MoO) film, tungsten oxide (WO) film, titanium oxynitride (TiON film), titanium aluminum carbonitride (TiAlCN film), titanium aluminum carbide (TiAlC film), and titanium carbonitride (TiCN film) are formed on wafer 200. In this pattern, the same effect as the pattern described above can also be obtained.

[0119] Furthermore, in the above-described sample, an N- and H-containing gas was used as an example of a N-containing reaction gas (nitriding gas) as the second processing gas. However, the present invention is not limited thereto. For example, as reactant gases, carbon-containing (C) gases such as ethylene (C₂H₄), acetylene (C₂H₂), and propylene (C₃H₆), boron-containing (B) gases such as diborane (B₂H₆) and trichloroborane (BCl₃), oxygen (O₂), ozone (O₃), plasma-excited O₂ (O₂*), O₂ + hydrogen (H₂), water vapor (H₂O), hydrogen peroxide (H₂O₂), nitrous oxide (N₂O), nitric oxide (NO), nitrogen dioxide (NO₂), carbon monoxide (CO), and carbon dioxide (CO₂) are used. Furthermore, in this specification, the phrase "O₂ + H₂" generally refers to a mixture of H₂ and O₂ gases. When supplying a mixed gas, the two gases can be mixed (premixed) in the supply pipe before being supplied to the processing chamber 201, or the two gases can be supplied to the processing chamber 201 separately from different supply pipes and mixed (postmixed) in the processing chamber 201. One or more of these can be used as the second processing gas. In this sample, the same effect as described above can also be obtained.

[0120] Furthermore, in the above-described sample, an example was shown where a SiN film was formed on wafer 200 during substrate processing. However, the present invention is not limited to this. Besides SiN films, the present invention can also be applied to the formation of films containing Si, such as silicon carbonitride (SiCN), silicon oxynitride (SiON), silicon oxycarbonate (SiOC), silicon oxycarbonate (SiOCN), boron silicon carbonitride (SiBCN), silicon boron nitride (SiBN), and silicon oxide (SiO). In this sample, the same effects as in the above-described sample can also be obtained.

[0121] Furthermore, in the above-described embodiment, a case was illustrated where a raw material gas was used as the first processing gas and a reactant gas was used as the second processing gas. However, the present invention is not limited thereto. For example, a reactant gas may be supplied as the first processing gas from a first supply port and a second supply port, and a raw material gas may be supplied as the second processing gas from a third supply port. In this embodiment, at least a portion of the same effects as in the above-described embodiment can be obtained.

[0122] The formulas used in each process are preferably prepared individually according to the processing content, and recorded and stored in the memory device 121c via a telecommunication line and external memory device 123. Furthermore, it is preferable that when each process begins, the CPU 121a appropriately selects a suitable formula from the multiple formulas recorded and stored in the memory device 121c according to the processing content. In this way, films of various types, compositions, qualities, and thicknesses can be formed with good reproducibility using a single substrate processing device. In addition, it reduces the operator's workload, avoids operational errors, and allows for rapid initiation of each process.

[0123] The above-mentioned formula is not limited to the case of making a new one. For example, it can also be prepared by changing an existing formula that is already installed in the substrate processing device. In the case of changing the formula, the changed formula can also be installed in the substrate processing device via a telecommunication line or a recording medium containing the formula. In addition, the existing formula that is already installed in the substrate processing device can be directly changed by operating the input / output device 122 of the existing substrate processing device.

[0124] In the above-described example, an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at a time was described. The present invention is not limited to the above-described example; for example, it can also be appropriately applied when forming a film using a single-piece substrate processing apparatus that processes one or several substrates at a time. Furthermore, in the above-described example, an example of forming a film using a substrate processing apparatus with a hot-wall type processing furnace was described. The present invention is not limited to the above-described example; it can also be appropriately applied when forming a film using a substrate processing apparatus with a cold-wall type processing furnace. Furthermore, in the above-described example, an example of activating gas using heat was described. However, the present invention is not limited to this. For example, it can also be appropriately applied when activating gas by plasma generated inside or outside the processing chamber 201, or when activating gas by irradiating it with electromagnetic waves using a lamp or the like.

[0125] When using such substrate processing apparatus, each processing procedure and processing condition can be performed in the same way as the above-described state and variation examples, and the same effect as the above-described state and variation examples can be obtained.

[0126] The above methods and variations can be used in appropriate combinations. In this case, the processing procedures and processing conditions can be set to be the same as those of the above methods and variations. [Simplified Explanation of the Diagram]

[0007] Figure 1 is a schematic structural diagram of a longitudinal processing furnace of a substrate processing apparatus suitable for use in one embodiment of the present invention, showing a longitudinal sectional view of the processing furnace 202. Figure 2 is a schematic structural diagram of a longitudinal processing furnace of a substrate processing apparatus suitable for use in one embodiment of the present invention, showing a cross-sectional view of the processing furnace 202 along line AA in Figure 1. Figure 3 is a schematic structural diagram of a controller 121 of a substrate processing apparatus suitable for use in one embodiment of the present invention, showing a block diagram of the control system of the controller 121. Figure 4 is a processing flow diagram in one embodiment of the present invention, showing the timing of the supply of the first processing gas, the second processing gas, and the inert gas and the switching state of the APC valve 244. Figure 5 is a processing flow diagram excerpted from steps A and B of the processing flow in Modification 1 of the present invention. Figure 6 is a processing flow diagram in Modification 2 of the present invention. Figure 7 is a processing flow diagram excerpted from steps A and B of the processing flow in Modification 3 of the present invention.

Claims

1. A substrate processing method comprising the step of forming a film on a substrate by performing a first cycle a predetermined number of times, wherein the first cycle comprises: (a) supplying a first processing gas to the substrate, and (b) supplying a second processing gas to the substrate; wherein in (a), the following steps are performed sequentially: (a-1) opening a first storage compartment pre-filled with the first processing gas in a pressurized state, and supplying the first processing gas released from the first storage compartment to the substrate in a depressurized processing chamber via a first supply port; (a-2) venting the processing space of the substrate while the supply of the first processing gas to the substrate is stopped; and (a-3) opening a second storage compartment pre-filled with the first processing gas in a pressurized state, and supplying the first processing gas released from the second storage compartment to the substrate in the depressurized processing chamber via a second supply port different from the first supply port.

2. The substrate processing method as described in claim 1, wherein, In (a-1) and (a-3), the first processing gas is supplied to the substrate while the aforementioned processing space is being vented.

3. The substrate processing method as described in claim 2, wherein, In (a-1) and (a-3), the opening degree of the exhaust valve installed in the exhaust path of the above-mentioned processing space in the state of exhausting the above-mentioned processing space is set to be larger than the opening degree in the state of exhausting the above-mentioned processing space in (b).

4. The substrate processing method as described in claim 1, wherein, In (a), (a-1') is further performed: after (a-3), the first storage section filled with the first processing gas is opened, and the first processing gas released from the first storage section is supplied to the substrate through the first supply port.

5. The substrate processing method as described in claim 4, wherein, In (a), (a-4) is further performed: after (a-3) and before (a-1'), the processing space is vented while the supply of the first processing gas to the substrate is stopped.

6. The substrate processing method as described in claim 1, wherein, In (a), the second loop (a-1), (a-2), and (a-3) will be executed more than twice the predetermined number of times.

7. The substrate processing method as described in claim 6, wherein, The supply amount of the first processing gas in the (k+1)th (a-1)th cycle of the second cycle is different from the supply amount of the first processing gas in the (k)th (a-1)th cycle.

8. The substrate processing method as described in claim 1, wherein, In (a-2), while supplying inert gas to the above-mentioned processing space, the processing space is also vented.

9. The substrate processing method as described in claim 1, wherein, The membrane is formed by performing the first cycle twice or more a predetermined number of times.

10. The substrate processing method as described in claim 1, wherein, In (a-1), when the first processing gas remains in the first storage section, the release of the first processing gas from the first storage section is stopped.

11. The substrate processing method as described in claim 10, wherein, After stopping the release of the first processing gas in (a-1), during the execution of at least one of (a-2) and (a-3), a further step is performed to fill the first storage unit with the first processing gas without discharging the first processing gas from the first storage unit.

12. The substrate processing method as described in claim 1, wherein, The execution time of (a-2) is longer than that of (a-1).

13. The substrate processing method as described in claim 1, wherein, The first storage unit is connected to the first supply port via a first piping, and the second storage unit is connected to the second supply port via a second piping independent of the first piping.

14. The substrate processing method as described in claim 1, wherein, The first supply port and the second supply port are configured to supply the first processing gas from the outer periphery of the substrate into the surface of the substrate, and at least one of the first supply port and the second supply port is configured to supply the first processing gas in a direction different from the direction toward the center of the substrate.

15. The substrate processing method as described in claim 1, wherein, The first processing gas contains predetermined elements, and the membrane is a membrane containing the predetermined elements.

16. The substrate processing method as described in claim 15, wherein, The first processing gas is a gas containing bonds between the aforementioned predetermined elements.

17. The substrate processing method as described in claim 1, wherein, In (a-2), a modified gas is supplied to the substrate, and the modified gas system prevents the first processing gas from being adsorbed onto the substrate.

18. A method for manufacturing a semiconductor device, comprising the step of forming a film on a substrate by performing a first cycle a predetermined number of times, wherein the first cycle is performed non-simultaneously: (a) supplying a first processing gas to the substrate, and (b) supplying a second processing gas to the substrate; in (a), the following steps are performed sequentially: (a-1) opening a first storage compartment pre-filled with the first processing gas in a pressurized state, and supplying the first processing gas released from the first storage compartment to the substrate in a depressurized processing chamber via a first supply port; (a-2) venting the processing space of the substrate while the supply of the first processing gas to the substrate is stopped; and (a-3) opening a second storage compartment pre-filled with the first processing gas in a pressurized state, and supplying the first processing gas released from the second storage compartment to the substrate in the depressurized processing chamber via a second supply port different from the first supply port.

19. A program by which a computer causes a substrate processing apparatus to execute the following procedure, wherein a film is formed on a substrate by performing a first cycle a predetermined number of times, the first cycle comprising: (a) a procedure of supplying a first processing gas to the substrate, and (b) a procedure of supplying a second processing gas to the substrate; wherein in (a), the following procedures are performed sequentially: (a-1) opening a first storage compartment pre-filled with the first processing gas in a pressurized state, and supplying the first processing gas released from the first storage compartment to the substrate in a depressurized processing chamber via a first supply port; (a-2) venting the processing space of the substrate while the supply of the first processing gas to the substrate is stopped; and (a-3) opening a second storage compartment pre-filled with the first processing gas in a pressurized state, and supplying the first processing gas released from the second storage compartment to the substrate in the depressurized processing chamber via a second supply port different from the first supply port.

20. A substrate processing apparatus, comprising: A first gas supply system includes a first storage section and a first supply port configured to supply a first processing gas filled in the first storage section to a substrate; a second gas supply system includes a second storage section and a second supply port configured to supply the first processing gas filled in the second storage section to the substrate, but different from the first supply port; a third gas supply system configured to supply a second processing gas to the substrate; an exhaust system configured to exhaust the processing space of the substrate; and a control unit configured to enable the first gas supply system, the second gas supply system, the third gas supply system, and the exhaust system to perform a process including forming a film on the substrate by performing a first cycle a predetermined number of times. The first cycle includes (a) a process of supplying the first processing gas to the substrate and (b) a process of supplying the second processing gas to the substrate. In (a), the following processes are performed sequentially: (a-1) A process in which the first storage section, which is pre-filled with the first processing gas in a pressurized state, is opened, and the first processing gas is supplied to the substrate in the depressurized processing chamber through the first supply port; (a-2) A process in which the processing space is vented when the supply of the first processing gas to the substrate is stopped; and (a-3) A process in which the second storage section, which is pre-filled with the first processing gas in a pressurized state, is opened, and the first processing gas is supplied to the substrate in the depressurized processing chamber through the second supply port.

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