Substrate processing method, semiconductor device manufacturing method, program product, and substrate processing apparatus

Abstract

The present invention relates to a substrate processing method, a semiconductor device manufacturing method, a program product, and a substrate processing apparatus. The present invention aims to provide a technology capable of improving step coverage of a film formed on a substrate. The means for solving the problem is to form a film containing a first element and a second element on a substrate by performing a cycle including the following processes a predetermined number of times: (a) a process of supplying a first gas containing the first element and a first halogen element to the substrate at a first flow rate; (b) a process of supplying a second gas containing the first element and different from the first gas to the substrate at a second flow rate greater than the first flow rate; and (c) a process of supplying a third gas containing the second element to the substrate after (b).

Description

Technical Field

[0001] This invention relates to substrate processing methods, semiconductor device manufacturing methods, process products, and substrate processing apparatus. Background Technology

[0002] As a step in the substrate processing process (the manufacturing process of semiconductor devices), a process of forming a film on the substrate is sometimes performed (see, for example, Patent Document 1).

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

[0004] The problem that the invention aims to solve This invention provides a technique for improving the step coverage of films formed on a substrate.

[0005] Methods for solving problems According to one aspect of the present invention, a technique is provided in which a film comprising the aforementioned first element and the aforementioned second element is formed on a substrate by performing a predetermined number of cycles comprising the following steps: (a) A process of supplying a first gas containing a first element and a first halogen element to a substrate at a first flow rate; (b) A process of supplying the substrate with a second gas containing the first element and different from the first gas at a second flow rate greater than the first flow rate; and (c) A process following (b) of supplying the aforementioned substrate with a third gas containing the second element.

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

[0007] Figure 1 This is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus that can be suitably used in one aspect of the present invention, showing the portion of the processing furnace 202 in a longitudinal cross-sectional view.

[0008] Figure 2 This is a schematic diagram of a vertical processing furnace of a substrate processing apparatus suitable for use in one embodiment of the present invention. Figure 1 The AA-line cross-sectional view shows part of the processing furnace 202.

[0009] Figure 3This is a schematic configuration diagram of the controller 121 of a substrate processing apparatus that can be suitably used in one aspect of the invention, and is a block diagram illustrating the control system of the controller 121.

[0010] Figure 4 This is a diagram illustrating the processing sequence in one embodiment of the invention, and a diagram illustrating the partial pressure variations of the first to third gases, the shift in the opening degree of the APC valve 244, and the opening and closing states of the downstream valve (valve 242b) of the storage tank 240b.

[0011] Figure 5 (a) is an enlarged cross-sectional view of the wafer 200 after step A. Figure 5 (b) is an enlarged cross-sectional view of the wafer 200 after step B. Figure 5 (c) is an enlarged cross-sectional view of the wafer 200 after step C.

[0012] Figure 6 This is a diagram showing the processing sequence in Modification 1 of the present invention, and a diagram showing the partial pressure variation of the first to third gases, the shift in the opening degree of the APC valve 244, and the opening and closing state of the downstream valve (valve 242b) of the storage tank 240b.

[0013] Explanation of reference numerals in the attached figures 200 wafers (substrates) Detailed Implementation

[0014] <One aspect of the invention> The following is mainly based on Figures 1-4 , Figure 5 (a) in Figure 5 Section (c) describes one aspect of the invention. It should be noted that the drawings used in the following description are schematic, and the dimensional relationships and ratios of the elements in the drawings may not necessarily correspond to reality. Furthermore, the dimensional relationships and ratios of the elements may not be consistent between different drawings.

[0015] (1) Composition of substrate processing device like Figure 1 As shown, the processing furnace 202 has a heater 207 that functions as a temperature regulator (heating unit). The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) the gas by heat.

[0016] A reaction tube 203 is arranged concentrically with the heater 207 inside the heater 207. The reaction tube 203 is formed into a cylindrical shape that is closed at the top and open at the bottom. A manifold 209 is arranged concentrically with the reaction tube 203 below the reaction tube 203. An O-ring 220a as a sealing component is provided between the manifold 209 and the reaction tube 203. 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 as a substrate. The wafer 200 is processed in the processing chamber 201.

[0017] Inside the processing chamber 201, nozzles 249a to 249c, serving as the first to third supply units, are respectively installed through the side wall of the manifold 209. Gas supply pipes 232a to 232c are connected to the nozzles 249a to 249c respectively.

[0018] On gas supply pipes 232a and 232c, mass flow controllers (MFCs) 241a and 241c, serving as flow controllers (flow control units), and valves 243a and 243c, serving as on / off valves, are sequentially installed from the upstream side of the airflow. Gas supply pipe 232e is connected to the downstream side of valve 243a in gas supply pipe 232a. Gas supply pipe 232g is connected to the downstream side of valve 243c in gas supply pipe 232c. On gas supply pipes 232e and 232g, MFCs 241e and 241g and valves 243e and 243g are sequentially installed from the upstream side of the airflow. On gas supply pipe 232b, MFC 241b, valve 243b, a storage tank 240b, which is configured as a gas storage unit capable of temporarily storing gas, and valve 242b are sequentially installed from the upstream side of the airflow. Gas supply pipes 232d and 232f are connected downstream of valve 242b in gas supply pipe 232b. MFCs 241d and 241f and valves 243d and 243f are sequentially installed on gas supply pipes 232d and 232f, starting from the upstream side of the gas flow.

[0019] The electrical conductivity between the storage tank 240b and the processing chamber 201 is preferably, for example, 1.5 × 10⁻⁶. -3 m 3The configuration is configured as described above. Furthermore, considering the ratio of the volume of the processing chamber 201 to the volume of the storage tank 240b, if the volume of the processing chamber 201 is 100L, the volume of the storage tank 240b is preferably set to, for example, 100 to 3000cc, and preferably to, for example, 1 / 1000 to 30 / 1000 times the volume of the processing chamber 201. It should be noted that, in addition to the storage tank 240b, or in addition to the storage tank 240b, the area of ​​the gas supply pipe 232b between valve 243b and valve 242b may also be used as a gas storage section.

[0020] like Figure 2 As shown, nozzles 249a to 249c are respectively arranged in the space between the inner wall of the reaction tube 203 and the wafer 200, in a manner that rises from the lower part of the inner wall of the reaction tube 203 along the upper part toward the arrangement direction of the wafer 200.

[0021] Nozzle 249c is positioned closer to the exhaust port 231a (described later) than nozzles 249a and 249b. When viewed from above, nozzles 249a and 249b are arranged linearly symmetrically about a straight line passing through the center of the reaction tube 203 and the center of the exhaust port 231a. Furthermore, 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 opposite (facing) nozzle 249c.

[0022] Gas supply holes 250a to 250c are respectively provided on the side of nozzles 249a to 249c for supplying gas. Gas supply holes 250a to 250c are respectively opened towards the center of reaction tube 203 when viewed from above, and can supply gas to wafer 200. There are multiple gas supply holes 250a to 250c in the range from the bottom to the top of reaction tube 203.

[0023] A first gas containing the first element and the first halogen element is supplied from the gas supply pipe 232a into the processing chamber 201 via MFC 241a, valve 243a, and nozzle 249a.

[0024] A second gas containing the first element and different from the first gas is supplied as a raw material gas from gas supply pipe 232b to processing chamber 201 via MFC 241b, valve 243b, storage tank 240b, valve 242b, and nozzle 249b.

[0025] A third gas containing the second element is supplied as a reactant gas from gas supply pipe 232c to processing chamber 201 via MFC 241c, valve 243c, and nozzle 249c.

[0026] A fourth gas containing metallic elements is supplied as a raw material gas from gas supply pipe 232d through MFC 241d, valve 243d, gas supply pipe 232c, and nozzle 249c into processing chamber 201.

[0027] Inactive gases are supplied to the treatment chamber 201 from gas supply pipes 232e-232g via MFCs 241e-241g, valves 243e-243g, gas supply pipes 232a-232c, and nozzles 249a-249c. The inactive gases function as purge gases, carrier gases, and dilution gases.

[0028] The first gas supply system mainly consists of gas supply pipe 232a, MFC 241a, and valve 243a. The second gas supply system mainly consists of gas supply pipe 232b, MFC 241b, valves 243b and 242b, and storage tank 240b. The third gas supply system mainly consists of gas supply pipe 232c, MFC 241c, and valve 243c. The fourth gas supply system mainly consists of gas supply pipe 232d, MFC 241d, and valve 243d. The inactive gas supply system mainly consists of gas supply pipes 232e-232g, MFC 241e-241g, and valves 243e-243g. Each of the first to fourth gas supply systems may be referred to individually or collectively as a gas supply system. It should be noted that nozzles connected to the gas supply pipes constituting the above-mentioned supply systems may also be included in their respective supply systems.

[0029] An exhaust port 231a is provided below the side wall of the reaction tube 203 for venting the atmosphere inside the processing chamber 201. An exhaust pipe 231, serving as an exhaust path, is connected to the exhaust port 231a. A vacuum pump 246, acting as a vacuum venting device, is connected to the exhaust pipe 231 via a pressure sensor 245 (a pressure detector, or pressure detection unit) and an APC (Auto Pressure Controller) valve 244 (a pressure regulator, or pressure regulating unit). The APC valve 244 is configured such that by opening and closing the valve while the vacuum pump 246 is operating, vacuum venting and stopping of vacuum venting within the processing chamber 201 can be performed. Furthermore, while the vacuum pump 246 is operating, the pressure inside the processing chamber 201 can be adjusted by regulating the valve opening based on the pressure information detected by the pressure sensor 245. The exhaust system mainly consists of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may also be included in the exhaust system.

[0030] 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, is provided below the sealing cover 219. The rotation shaft 255 of the rotation mechanism 267 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 crystal boat elevator 115, serving as a lifting mechanism, is configured as a conveying device (transfer mechanism) that moves the wafer 200 in and out of the processing chamber 201 by raising and lowering the sealing cover 219.

[0031] The crystal boat 217, which serves as a substrate support, is configured to support multiple wafers 200, for example 25 to 200, in a horizontal orientation and arranged in a straight line along the vertical direction with their centers aligned with each other, in a multi-layered manner, i.e., arranged at intervals. A heat insulation plate 218 is supported in multiple layers at the bottom of the crystal boat 217.

[0032] A temperature sensor 263, which serves as a temperature detector, is installed inside the reaction tube 203. By adjusting the energization of the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature inside the processing chamber 201 is adjusted to achieve the desired temperature distribution.

[0033] like Figure 3 As shown, the controller 121, serving as the control unit (control means), is configured as a computer equipped with a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, storage device 121c, and I / O port 121d are configured to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122, such as a touch panel, is connected to the controller 121. Furthermore, an external storage device 123 can be connected to the controller 121.

[0034] The storage device 121c is configured such as flash memory, HDD (Hard Disk Drive), or SSD (Solid State Drive). The storage device 121c records and stores in a readable manner a control program that controls the operation of the substrate processing apparatus, and a process flow that describes the substrate processing steps and conditions (described later). The process flow is formed by the controller 121 causing the substrate processing apparatus to execute each step of the substrate processing (described later) in a way that yields a predetermined result, and functions as a program. Hereinafter, the process flow, control program, etc., will be generally referred to as a program (program product). Furthermore, the process flow will be referred to simply as a process. When the term "program" is used in this specification, there may be cases where only the process flow is included, cases where only the control program is included, or cases where both are included. RAM 121b is configured as a memory area that temporarily holds programs, data, etc., read by the CPU 121a.

[0035] I / O port 121d is connected to the aforementioned MFC 241a~241g, valves 243a~243g, 242b, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotating mechanism 267, crystal boat lift 115, etc.

[0036] CPU 121a is configured to read and execute control programs from storage device 121c, and to read processes from storage device 121c based on inputs such as operation commands from input / output device 122. CPU 121a is configured to perform the following according to the read processes: flow regulation of various substances (various gases) based on MFC 241a to 241g, opening and closing of valves 243a to 243g and 242b, opening and closing of APC valve 244, pressure regulation based on pressure sensor 245 and using APC valve 244, starting and stopping of vacuum pump 246, temperature regulation of heater 207 based on temperature sensor 263, rotation and rotation speed regulation of crystal boat 217 based on rotation mechanism 267, and lifting of crystal boat 217 based on crystal boat lift 115.

[0037] The controller 121 can be configured to install the aforementioned program, recorded and stored in the external storage device 123, into the computer. The external storage device 123 includes, for example, a hard disk such as an HDD, an optical disk such as a CD, a USB flash drive, or a semiconductor storage device such as an SSD. The storage device 121c and the external storage device 123 constitute a computer-readable recording medium. Hereinafter, they will also be generally referred to simply as recording media. When the term "recording medium" is used in this specification, there may be a case where only the storage device 121c is included, a case where only the external storage device 123 is included, or a case where both are included. It should be noted that the program can also be provided to the computer using a communication unit such as the Internet or a dedicated line, without using the external storage device 123.

[0038] (2) Processing procedures Main use Figure 4 , Figure 5 (a) in Figure 5 Section (c) describes a method for processing a substrate using the aforementioned processing apparatus as a step in the manufacturing process of a semiconductor device, namely, an example of a processing sequence for forming a film on a wafer 200 that serves as a substrate. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

[0039] In this method, an example of a wafer 200 with recesses such as grooves, slots, and holes formed on its surface as a three-dimensional structure will be described.

[0040] It should be noted that, in this specification, the term "recess" is not limited to shapes with a bottom surface, and may sometimes include structures such as gaps or through holes that do not have a bottom surface. In the case of structures without a bottom surface, "bottom side" sometimes refers to the direction (side) from each opening toward the inside of the structure when viewed from two or more openings.

[0041] In this processing sequence, a film containing the first element and the second element is formed on the wafer 200 by repeating the following steps a predetermined number of times (n1 times, where n1 is an integer of 1 or 2 or more): (a) Step A: supplying a first gas containing a first element and a first halogen element to the wafer 200 at a first flow rate; (b) Step B, which involves supplying a second gas containing the first element and different from the first gas to the wafer 200 at a second flow rate greater than the first flow rate; and (c) Step C, which involves supplying the wafer 200 with a third gas containing the second element after step B.

[0042] The following examples illustrate the loop described above, including the case of (d): (d) Between steps A and B, in step D, while the supply of the first gas is stopped, the opening of the APC valve is changed from the first opening to the second opening.

[0043] The following examples illustrate the case of loop (e) mentioned above: (e) Between step A and step B, in the state of stopping the supply of the first gas, step E is taken to change the pressure in the processing chamber 201 from the first pressure to the second pressure.

[0044] In the following examples, such as Figure 4 The following description illustrates the processing sequence, explaining the cases where purging and vacuum venting are performed between steps A and B, between steps B and C, and after step C. In this method, as an example, the case where purging and vacuum venting are performed sequentially will be explained.

[0045] Figure 4 The processing sequence is schematically illustrated. Here, the execution periods of steps A, B, and C are respectively referred to as A, B, and C. The first gas, the second gas, and the third gas are respectively referred to as 1, 2, and 3, and the flash supply of the second gas is referred to as 2F. Furthermore, purging and vacuum exhaust are referred to as P / V. Figure 4 The diagram schematically illustrates the changes in the partial pressure of each gas during processing, the shift in the opening degree (valve opening) of APC valve 244, and the opening and closing of valve 242b, which serves as the downstream valve of storage tank 240b. These aspects are... Figure 6 The same applies to the middle. Details regarding flash supply, purging, and vacuum exhaust will be described later.

[0046] For convenience, the above processing order is sometimes represented as follows in this specification. The same expression is also used in the following descriptions of variations and other methods.

[0047] (Gas 1 → P / V → Gas 2 → P / V → Gas 3 → P / V) × n1 The term "wafer" as used in this specification can refer to the wafer itself, or to a laminate of the wafer and a specified layer or film formed on its surface. The term "surface of the wafer" as used in this specification can refer to the surface of the wafer itself, or to the surface of a specified layer, etc., formed on the wafer. In this specification, when described as "forming a specified layer on the wafer," it can mean forming the specified layer directly on the surface of the wafer itself, or forming the specified layer on a layer, etc., formed on the wafer. In this specification, the use of "substrate" is also synonymous with the use of "wafer."

[0048] As used in this specification, the terms "substance" and "agent" include at least one of gaseous and liquid substances. Liquid substances include mist substances.

[0049] As used in this specification, the term "layer" includes at least one of continuous layers and discontinuous layers. For example, layers 1 through 3 described later may include continuous layers, discontinuous layers, or both.

[0050] In this specification, when describing the adsorption and reaction of the first to fourth gases onto the surface of the wafer 200, it includes not only the adsorption and reaction of the gases onto the wafer surface in their undecomposed state, but also the adsorption and reaction of intermediates generated by their decomposition and ligand release onto the surface of the wafer 200.

[0051] (Wafer filling and crystal boat loading) When multiple wafers 200 are loaded into the crystal boat 217, such as Figure 1 As shown, a crystal boat 217 supporting multiple wafers 200 is moved into the processing chamber 201 by a crystal boat elevator 115 (crystal boat loading).

[0052] (Pressure and temperature regulation) After the crystal boat loading is completed, vacuum exhaust (pressure reduction exhaust) is performed by vacuum pump 246 to bring the pressure (vacuum level) inside processing chamber 201, i.e., the space where wafer 200 exists, to the desired pressure. Additionally, wafer 200 inside processing chamber 201 is heated by heater 207 to the desired processing temperature. Furthermore, rotation of wafer 200 is initiated based on rotation mechanism 267. Exhausting gas from processing chamber 201, heating wafer 200, and rotation all continue at least until the processing of wafer 200 is completed.

[0053] (The second gas is filled into the storage tank 240b) With valve 242b closed, valve 243b is opened, allowing the second gas to flow into gas supply pipe 232b. The flow rate of the second gas is regulated by MFC 241b and supplied to storage tank 240b. This allows a predetermined amount of the second gas to be pressurized to the filling pressure and filled into storage tank 240b. After the predetermined amount of the second gas has been filled into storage tank 240b, valve 243b is closed, maintaining the state of the second gas filling in storage tank 240b.

[0054] (Film-forming treatment) Then, proceed with the following steps A, B, and C in sequence.

[0055] [Step A] In step A, a first gas containing a first element and a first halogen element is supplied to the wafer 200 in the processing chamber 201.

[0056] Specifically, valve 243a is opened, allowing the first gas to flow into gas supply pipe 232a. The first gas is regulated by MFC 241a to supply a substantially constant flow rate and velocity into processing chamber 201 via nozzle 249a and is exhausted through exhaust port 231a. At this time, the first gas is supplied to wafer 200 (first gas supply). At this time, valves 243e to 243g can also be opened to supply inactive gases into processing chamber 201 via nozzles 249a to 249c, respectively. At this time, the opening degree (valve opening degree) of APC valve 244 is adjusted to a state between fully open and fully closed, that is, the opening degree that makes the pressure in processing chamber 201 reach the specified processing pressure (first pressure) (hereinafter also referred to as the first opening degree). It should be noted that the flow rate and velocity of the first gas may vary during at least a portion of step A.

[0057] Examples of processing conditions for supplying the first gas in step A can be shown below: Processing temperature: 250–900℃, preferably 650–850℃ Processing pressure (first pressure): 10–10000 Pa, preferably 20–5000 Pa First gas supply flow rate (first flow rate): 0.1–3 slm First gas supply time: 1–120 seconds, preferably 1–60 seconds Inactive gas supply flow rate (per gas supply pipe): 0-20 slm.

[0058] In this specification, the flow rate of the first gas supplied to the wafer 200 under the above-described processing conditions is referred to as the first flow rate. Furthermore, the execution time of step A (e.g., the first gas supply time) is longer than the execution time of step B (e.g., the second gas supply time) described later.

[0059] It should be noted that the numerical range "250~900℃" in this specification refers to the lower and upper limits being included within that range. Therefore, for example, "250~900℃" means "above 250℃ and below 900℃". The same applies to other numerical ranges. Furthermore, 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 other words, the pressure of the space where the wafer 200 exists. Additionally, the processing time refers to the duration of the processing. Also, when the supply flow rate includes 0 slm, 0 slm means that the substance (gas) is not supplied. These same principles apply in the following descriptions.

[0060] By supplying a first gas containing a first element and a first halogen element to the wafer 200 under the above processing conditions, the first gas is preferentially adsorbed on the opening side of the recess, thereby forming a first layer containing the first element and having a first halogen element formed on its surface (first halogen end capping) (see...). Figure 5 (a) in the middle.

[0061] In the first layer, the adsorption of at least a portion of the molecular structure of the molecules constituting the second gas supplied in step B, as described later, is suppressed (hindered) by the formation of a first halogen end cap on the surface. In other words, the first layer constitutes an adsorption barrier layer that prevents at least a portion of the molecular structure constituting the second gas from adsorbing on the first layer.

[0062] When the first element is silicon (Si), a gas containing a halosilane can be used as the first gas, for example. The first halogen elements include chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc.

[0063] As the first gas, for example, chlorosilane gases such as tetrachlorosilane (SiCl4), monochlorosilane (SiH3Cl), dichlorosilane (SiH2Cl2), and trichlorosilane (SiHCl3) can be used, that is, gases in which there are no Si-Si bonds between atoms of the first element in a single molecule. In addition to chlorosilanes, gases such as fluorosilanes such as tetrafluorosilane (SiF4) and difluorosilane (SiH2F2), bromosilanes such as tetrabromosilane (SiBr4) and dibromosilane (SiH2Br2), and iodosilanes such as tetraiodosilane (SiI4) and diiodosilane (SiH2I2) can also be used as the first gas, that is, gases in which there are no Si-Si bonds between atoms in a single molecule.

[0064] In addition, as the first gas, for example, chlorosilane gases such as hexachlorodisilane (Si2Cl6), octachlorotrisilane (Si3Cl8), monochlorodisilane (Si2H5Cl), dichlorodisilane (Si2H4Cl2), trichlorodisilane (Si2H3Cl3), tetrachlorodisilane (Si2H2Cl4), monochlorotrisilane (Si3H5Cl), and dichlorotrisilane (Si3H4Cl2) can be used, that is, gases containing Si bonds between each other (Si-Si bonds) in one molecule.

[0065] As the first gas, one or more of these can be used.

[0066] As inert gases, rare gases such as nitrogen (N2), argon (Ar), helium (He), neon (Ne), and xenon (Xe) can be used. One or more of these can be used as inert gases. This also applies to the steps described later.

[0067] After the first layer (adsorption barrier layer) is formed on the surface inside the recess of the wafer 200, the valve 243a is closed to stop the supply of the first gas into the processing chamber 201.

[0068] [Step D + Step E] Then, the opening of APC valve 244 is increased from the first opening. Specifically, the opening of APC valve 244 is adjusted to a substantially fully open state (hereinafter also referred to as the second opening), that is, an opening that brings the processing chamber 201 to a predetermined pressure (the second pressure). Then, valves 243e to 243g are opened, and inert gas is supplied to the processing chamber 201 through nozzles 249a to 249c. The inert gas supplied from nozzles 249a to 249c acts as a purge gas, thereby purging the processing chamber 201. Then, valves 243e to 243g are closed, and the supply of inert gas to the processing chamber 201 is stopped. Then, a vacuum is applied to the processing chamber 201 to remove gaseous substances and the like remaining in the processing chamber 201.

[0069] It should be noted that, in this context, "purging" refers to removing intermediates and other byproducts of the first gas present in the processing chamber 201 by supplying an inert gas into the processing chamber 201. "Vacuum exhaust" refers to removing intermediates of the first gas present in the processing chamber 201 without supplying an inert gas. Furthermore, "no inert gas supply" in "vacuum exhaust" means that no purging gas is supplied; however, a carrier gas or a small amount of inert gas may also be supplied. Additionally, "intermediates of the first gas" primarily refers to substances obtained by the thermal decomposition of the first gas within the processing chamber 201.

[0070] [Step B] In step B, a second gas containing the first element is supplied to the wafer 200 in the processing chamber 201.

[0071] Specifically, with valve 243b closed, valve 242b is opened to supply the second gas from storage tank 240b to processing chamber 201. The second gas, which is filled in storage tank 240b and pressurized, is supplied in a single pass through nozzle 249b to the depressurized processing chamber 201 and exhausted through exhaust port 231a. At this time, the second gas is supplied to wafer 200 (second gas supply). In this specification, the gas supply method of supplying the pressurized gas to wafer 200 using a pressure difference is also referred to as flash supply. At this time, valves 243e to 243g may also be opened to supply inactive gas into gas supply pipes 232a to 232c.

[0072] Examples of processing conditions for supplying the second gas in step B can be shown as follows: Processing temperature: 250–900℃, preferably 650–850℃ Processing pressure (second pressure lower than the first pressure): 1–2666 Pa, preferably 1–1333 Pa Second gas filling pressure: 60–1500 Torr, preferably 200–1200 Torr Second gas supply: 50–3000 cc, preferably 100–2000 cc The second gas supply time is 0.1 to 20 seconds, preferably 0.5 to 5 seconds. Inactive gas supply flow rate (per gas supply pipe): 0-20 slm.

[0073] Under the aforementioned processing conditions, the second gas stored in the storage tank 240b is released into the depressurized processing chamber 201 in a single release. Therefore, a second gas with a flow rate greater than the first flow rate and a flow velocity greater than the first flow velocity can be supplied to the wafer 200. This allows the second gas to reach the bottom side of the recessed portion of the wafer 200. It should be noted that the supply flow rate and supply velocity of the second gas in step B are different from those in step B. Figure 4 The partial pressure variation of the second gas shown also changes in a manner that is maximum immediately after valve 242b opens, and then decreases. The second flow rate refers to the flow rate at least including the time point when the flow rate is maximum in step B. Similarly, the second flow velocity refers to the flow velocity at least including the time point when the flow velocity is maximum in step B.

[0074] By supplying a second gas containing the first element (specifically, a raw material gas containing the first element) to the wafer 200 under the aforementioned processing conditions, the second gas is adsorbed onto the surface within the recess and onto the portion of the first layer where the first halogen end cap is not formed (e.g., the bottom side of the recess), thereby forming a second layer containing the first element (see [link to documentation]). Figure 5 (b) in the middle.

[0075] As described above, the opening degree (second opening degree) of APC valve 244 in step B is adjusted to be greater than the opening degree (first opening degree) of APC valve 244 in step A. This allows the exhaust velocity in processing chamber 201 in step B to be greater than the exhaust velocity in processing chamber 201 in step A. By relatively increasing the exhaust velocity in processing chamber 201 in step B, the flow rate of the second gas supplied in step B (second flow rate) can be made greater than the flow rate of the first gas supplied in step A (first flow rate). By relatively increasing the flow rate of the second gas supplied in step B, the residence time of the second gas in processing chamber 201 in step B can be shorter than the residence time of the first gas in processing chamber 201 in step A.

[0076] As the second gas, for example, a gas containing a Si-containing substance can be used, which includes Si as the main element (first element) constituting the formed film. Alternatively, a substance containing a second halogen element, i.e., a gas containing a halosilane, can also be used as the second gas. The second halogen element may include Cl, F, Br, I, etc. The first halogen element and the second halogen element may be the same or different.

[0077] As the second gas, more than one gas from the substances listed as the first gas can be used. However, the second gas and the first gas are gases with different molecular structures (chemical structures). For example, a gas containing bonds between atoms of the first element can be used as the second gas, and a gas not containing bonds between atoms of the first element can be used as the first gas. Furthermore, from other perspectives, for example, a gas whose thermal decomposition temperature is lower than that of the first gas can be used as the second gas.

[0078] In addition to these, other substances containing amino groups and Si, such as aminosilanes, can also be used as the second gas.

[0079] As the second gas, gases containing aminosilanes such as tetra(dimethylamino)silane (Si[N(CH3)2]4), tri(dimethylamino)silane, bis(diethylamino)silane (Si[N(C2H5)2]2H2), bis(tert-butylamino)silane (SiH2[NH(C4H9)]2), and (diisopropylamino)silane (SiH3[N(C3H7)2]) can also be used. One or more of these can be used as the second gas.

[0080] After the second layer is formed on the surface within the recess of wafer 200, valve 242b is closed to stop the supply of the second gas to processing chamber 201. Then, processing chamber 201 is purged using the same processing steps and conditions as in steps D+E. Then, vacuum exhaust is performed on processing chamber 201 using the same processing steps and conditions as in steps D+E. It should be noted that purging or vacuum exhaust in processing chamber 201 can also begin with valve 242b open.

[0081] Furthermore, the execution period of step B can be understood as the period from the opening of valve 242b to the start of supplying the second gas until the closing of valve 242b to the stop of supplying the second gas. Alternatively, the execution period of step B can also be understood as the period from the opening of valve 242b to the start of purging or vacuum exhaust within the processing chamber 201.

[0082] [Step C] Then, a third gas containing the second element is supplied to the wafer 200 in the processing chamber 201.

[0083] Specifically, valve 243c is opened, allowing the third gas to flow into gas supply pipe 232c. The third gas, with flow rate regulated by MFC 241c, is supplied to processing chamber 201 via nozzle 249c and exhausted through exhaust port 231a. At this time, the third gas is supplied to wafer 200 (third gas supply). Alternatively, valves 243e to 243g can be opened to supply inactive gases to processing chamber 201 via nozzles 249a to 249c, respectively. At this time, the opening of APC valve 244 is reduced from its fully open state (second opening). Specifically, the opening of APC valve 244 is adjusted to a state between fully open and fully closed, i.e., an opening that brings the pressure in processing chamber 201 to the desired processing pressure.

[0084] Examples of processing conditions for supplying the third gas in this step can be shown as follows: Processing temperature: 250–900℃, preferably 650–850℃ Processing pressure: 10–10000 Pa, preferably 20–5000 Pa The third gas supply flow rate is 0.001–20 slm, preferably 1–10 slm. The third gas supply time is 1–120 seconds, preferably 1–60 seconds. Inactive gas supply flow rate (per gas supply pipe): 0-20 slm.

[0085] By supplying a third gas containing the second element (specifically, a reaction gas containing the second element) to the wafer 200 under the aforementioned processing conditions, at least a portion of the second layer formed on the surface within the recess reacts with the third gas and is modified (see [reference]). Figure 5 (c)). As a result, a third layer (specifically, a third layer containing the second element) is formed on the surface inside the recess as a modified layer of the first and second layers.

[0086] When the second element is nitrogen (N), the third gas can be a gas containing both N and hydrogen (H) as a nitriding agent. The substance containing both N and H is both N-containing and H-containing. Examples of substances containing both N and H include hydrogen nitrides such as ammonia (NH3), diazepines (N2H2), hydrazine (N2H4), and N3H8 gas.

[0087] In addition to these, gases containing substances containing nitrogen (N), carbon (C), and hydrogen (H) can also be used as the third gas. Examples of substances containing N, C, and H include amines and organic hydrazines. A substance containing N, C, and H is simultaneously a substance containing N, a substance containing C, a substance containing H, and a substance containing both N and C.

[0088] As a third gas, for example, gases containing ethylamines such as monoethylamine (C2H5NH2), diethylamine ((C2H5)2NH), and triethylamine ((C2H5)3N), methylamines such as monomethylamine (CH3NH2), dimethylamine ((CH3)2NH), and trimethylamine ((CH3)3N), and organic hydrazines such as monomethylhydrazine ((CH3)HN2H2), dimethylhydrazine ((CH3)2N2H2), and trimethylhydrazine ((CH3)2N2(CH3)H) can be used.

[0089] As a third gas, one or more of these can be used.

[0090] After the third layer is formed on the surface within the recess of the wafer 200, valve 243c is closed to stop the supply of the third gas to the processing chamber 201. Then, the processing chamber 201 is purged using the same processing steps and conditions as in steps D+E. Then, the processing chamber 201 is vacuumed using the same processing steps and conditions as in steps D+E.

[0091] [Number of times stipulated for implementation] By performing steps A, B, and C sequentially n1 times (n1 being an integer of 1 or 2 or more) non-simultaneously (or in other words, alternately or intermittently), a film can be formed on the wafer 200. If the first element contained in the first and second gases is, for example, Si, and the second element contained in the third gas is, for example, N, a silicon nitride film (SiN film) can be formed on the surface of the wafer 200. The above-described cycle is preferably repeated multiple times until the film thickness formed by stacking the third layer reaches the desired thickness. Furthermore, for the second gas supplied via flash flow in step B of subsequent cycles, it is preferable to complete the filling of the storage tank 240b before the start of step B, for example, during the execution of step C before and after a cycle of purging, or during the execution of step A of that cycle and the subsequent steps D+E.

[0092] (Post-purge and atmospheric pressure recovery) After forming a film of the desired thickness on the surface within the recess of the wafer 200, inert gases are supplied as purge gases into the processing chamber 201 through nozzles 249a to 249c, and exhausted through exhaust port 231a. This purges the processing chamber 201, removing any gaseous substances remaining within it. Then, the atmosphere within the processing chamber 201 is replaced with the inert gas, and the pressure within the processing chamber 201 returns to atmospheric pressure.

[0093] (Crystal boat unloading and wafer removal) Then, the sealing cover 219 is lowered by the crystal boat lift 115, opening the lower end of the manifold 209. The wafer 200, supported by the crystal boat 217, is then moved from the lower end of the manifold 209 to the outside of the reaction tube 203. After the wafer 200 is moved to the outside of the reaction tube 203, it is removed from the crystal boat 217.

[0094] (3) The effects of this method According to this method, one or more of the following effects can be obtained.

[0095] (a) In step A, the flow rate of the first gas supplied to the wafer 200 (first flow rate) is made less than the flow rate of the second gas supplied to the wafer 200 in step B (second flow rate). By relatively reducing the flow rate of the first gas in step A, the residence time of the first gas on the surface of the wafer 200 (particularly the surface within the recess) can be relatively prolonged. Therefore, the adsorption probability of the first gas per unit flow rate on the wafer 200 can be increased, and the total exposure of the first gas per unit flow rate can be increased. As a result, it is easy to sufficiently ensure the exposure of the first gas to the wafer 200 in step A.

[0096] In step B, the flow rate of the second gas supplied to the wafer 200 (the second flow rate) is greater than the flow rate of the first gas supplied to the wafer 200 in step A (the first flow rate). By relatively increasing the flow rate of the second gas in step B, the residence time of the second gas on the surface of the wafer 200 (particularly the surface within the recess) can be relatively shortened. Therefore, the probability of thermal decomposition of the second gas can be reduced, and multiple adsorption of the second gas after thermal decomposition can be suppressed. As a result, the reduction in the step coverage of the film formed in the recess of the wafer 200 can be suppressed.

[0097] Furthermore, in step B, by forming a second layer from the second gas that has been adsorbed without thermal decomposition, a membrane with desired properties can be obtained in which at least a portion of the molecular structure of the second gas is contained in a maintained state. By producing a membrane in which at least a portion of the molecular structure of the second gas is contained in a maintained state, compared with a membrane without the molecular structure of the second gas, properties such as increased electron trap density, increased nitrogen concentration, and decreased refractive index can be imparted.

[0098] (b) In step B, the flow rate of the second gas supplied to the wafer 200 (second flow rate) is greater than the flow rate of the first gas supplied to the wafer 200 in step A (first flow rate). Furthermore, as described above, the flow rate of the second gas in step B is relatively increased. This allows for a relatively increased partial pressure of the second gas within the processing chamber 201 in step B, thus enabling the second gas to reach the lower (inner) side of the recess. As a result, the step coverage of the formed film can be improved.

[0099] (c) In step B, the residence time of the second gas in the processing chamber 201 is made shorter than the residence time of the first gas in the processing chamber 201 in step A. In this way, by relatively shortening the residence time of the second gas in the processing chamber 201 in step B, the thermal decomposition rate of the second gas can be reduced, and the degradation of the step coverage of the formed membrane can be suppressed.

[0100] (d) In step B, the exhaust velocity in processing chamber 201 is made greater than the exhaust velocity in processing chamber 201 in step A. In this way, by relatively increasing the exhaust velocity in processing chamber 201 in step B, the flow rate of the second gas in step B can be relatively increased. As a result, the aforementioned effect can be obtained.

[0101] (e) By making the opening degree of APC valve 244 in step B (the second opening degree) greater than the opening degree of APC valve 244 in step A (the first opening degree), the exhaust velocity in the processing chamber 201 in step B can be relatively increased. This, in turn, increases the flow rate of the second gas in step B. As a result, the aforementioned effects are achieved.

[0102] (f) By performing step D, the flow rate of the second gas in step B can be relatively increased. Thus, the above-mentioned effect can be obtained.

[0103] (g) In step B, the pressure (second pressure) inside the processing chamber 201 is lower than the pressure (first pressure) inside the processing chamber 201 in step A. In this way, by relatively reducing the pressure inside the processing chamber 201 in step B, the flow rate of the second gas in step B can be relatively increased. As a result, the aforementioned effects can be obtained.

[0104] (h) By performing step E, the pressure (second pressure) in the processing chamber 201 in step B can be made lower than the pressure (first pressure) in the processing chamber 201 in step A. This allows for a relative increase in the flow rate of the second gas in step B. As a result, the aforementioned effects can be achieved.

[0105] (i) Even when using a gas containing bonds between atoms of the first element as the second gas and a gas not containing bonds between atoms of the first element as the first gas, that is, even when using a gas with a relatively low thermal decomposition temperature as the second gas, in step B, by relatively increasing the flow rate of the second gas, it is possible to supply the second gas to the wafer 200 while suppressing thermal decomposition. Therefore, the second gas can be adsorbed onto the wafer 200 while maintaining the bonds between atoms of the first element. As a result, the step coverage can be improved, and a film containing bonds between atoms of the first element and having the desired film properties can be formed.

[0106] (j) By including the second halogen element in the second gas, thereby capping the surface of the second layer with the second halogen element, the reaction between the second layer and the third gas can be promoted.

[0107] (k) By starting step A before step B, an adsorption barrier layer that hinders the adsorption of the second gas can be formed on the opening side of the recess before the second gas is supplied. This improves the step coverage of the formed membrane.

[0108] (l) By starting step B after step A is completed, an adsorption barrier layer that prevents the adsorption of the second gas can be formed on the opening side of the recess before the second gas is supplied. As a result, the step coverage of the formed membrane can be further improved.

[0109] (m) The execution time of step A is longer than that of step B, thus ensuring sufficient exposure of the first gas to the surface of wafer 200 (the surface inside the recess).

[0110] (n) In step B, valve 242b is opened, thereby supplying the wafer 200 with a second gas that has been pressurized in storage tank 240b, so that the second gas can be supplied to the wafer 200 at a high flow rate and high partial pressure. As a result, the second gas can reach the bottom side (inner side) of the recess.

[0111] (4) Variations The processing order in this method can be changed as shown in the following variations. These variations can be combined arbitrarily. Unless otherwise specified, the processing steps and conditions in each step of each variation can be the same as the processing steps and conditions in each step of the above processing order.

[0112] (Variation Example 1) In this modified example, the processing sequence can also be modified by performing the following (f) cycle a predetermined number of times (n2 times, where n2 is an integer of 1 or 2 or more) in addition to steps A, B, C, etc., thereby forming a predetermined film on the wafer 200: (f) Step F, which involves supplying the second gas to the wafer 200 at a third flow rate less than the second flow rate and for a period longer than that of step B, after step B and before step C (see step F). Figure 6 The implementation period of step F is denoted as F).

[0113] In this variation, the purging and vacuum exhaust processes performed between step B and step F, and between step F and step C, are explained (see [reference]). Figure 6 ).

[0114] After the second layer is formed on the surface within the recess of wafer 200 (after step B), with valve 242b open, the processing chamber 201 is purged using the same processing steps and conditions as in steps D+E. Then, the processing chamber 201 is evacuated using the same processing steps and conditions as in steps D+E.

[0115] [Step F] Then, in step F, a second gas containing the first element and different from the first gas is supplied to the wafer 200 in the processing chamber 201. Specifically, valve 243b is opened to allow the second gas to flow into the gas supply pipe 232b. The second gas is regulated by MFC 241b to supply the processing chamber 201 at a substantially constant flow rate and velocity via nozzle 249b and is exhausted through exhaust port 231a. At this time, the second gas is supplied to the wafer 200 (second gas supply). At this time, valves 243e to 243g may also be opened to supply inactive gases into the processing chamber 201 via nozzles 249a to 249c, respectively. At this time, the opening of APC valve 244 is reduced from the fully open state (second opening). Specifically, the valve opening of APC valve 244 is adjusted to a state between fully open and fully closed, that is, an opening that brings the pressure in the processing chamber 201 to a predetermined processing pressure.

[0116] Examples of processing conditions for supplying the second gas in this step can be shown as follows: Processing temperature: 250–900℃, preferably 650–850℃ Processing pressure: 10–10000 Pa, preferably 20–5000 Pa The second gas supply flow rate is 0.001–20 slm, preferably 1–10 slm. Second gas supply time: 1–120 seconds, preferably 1–60 seconds Inactive gas supply flow rate (per gas supply pipe): 0-20 slm.

[0117] In this specification, the flow rate of the second gas supplied to the wafer 200 under the above processing conditions is referred to as the third flow rate. The flow rate of the second gas in step F (the third flow rate) is less than the flow rate of the second gas in step B (the second flow rate). In addition, the execution time of step F is longer than the execution time of step B.

[0118] By supplying a second gas containing the first element (specifically, a raw material gas containing the first element) to the wafer 200 under the aforementioned processing conditions, the second gas is adsorbed onto the surface within the recess and into the region of the first layer where the first halogen end cap is not formed, thereby forming a fourth layer containing the first element. Furthermore, the fourth layer is primarily formed on the surface region within the recess where the second layer is not formed. However, the fourth layer can also be formed on top of the second layer. It should be noted that the second and fourth layers containing the first element are described separately here, but the second and fourth layers can also be combined into a single layer containing the first element (a layer containing the first element). Additionally, the layer formed in step B by supplying the second gas and the layer formed in step F by supplying the second gas can also be combined into a second layer.

[0119] The second gas used in step F of this variation can be a gas containing a substance with the same molecular structure as the second gas in step B of the above-described manner.

[0120] After the fourth layer is formed on the surface within the recess of the wafer 200, valves 242b and 243b are closed to stop the supply of the second gas into the processing chamber 201 (step F ends).

[0121] Then, the opening of APC valve 244 is adjusted from a state between fully open and fully closed to a substantially fully open state (second opening). Then, the processing chamber 201 is purged using the same processing steps and conditions as in steps D+E. Then, the processing chamber 201 is evacuated using the same processing steps and conditions as in steps D+E.

[0122] The same effect as described above can be achieved in this variation. In this variation, by performing step F, that is, by supplying the second gas at a third flow rate lower than the second flow rate (i.e., non-flash supply) after supplying the second gas at a second flow rate (i.e., flash supply), the wafer 200 can be adequately supplied (exposed) with the second gas, thereby further improving the step coverage of the formed film. In addition, by adjusting the supply time and flow rate of the second gas in step F, the step coverage and film quality can be controlled.

[0123] (Variation Example 2) In this modified example, similar to modified example 1, the processing sequence can be such that a predetermined film is formed on the wafer 200 by performing a predetermined number of cycles that include step F in addition to steps A, B, C, etc.

[0124] In this variation, the cases in which purging and vacuum venting are not performed between step B and step F, i.e., steps B and F are performed continuously, and the cases in which purging and vacuum venting are performed between step F and step C will be described.

[0125] [Step B] Either valve 243b or valve 242b is opened, supplying the second gas from storage tank 240b to processing chamber 201. In step B of the above-described method, valve 242b is opened while valve 243b is closed to supply the second gas from storage tank 240b to processing chamber 201. However, in this modified example, either valve is opened simultaneously with the start of step B. That is, in step B, the second gas, whose flow rate is regulated by MFC 241b, along with the second gas stored in storage tank 240b, is continuously supplied from gas supply pipe 232b to processing chamber 201 and wafer 200. Apart from this, the processing steps and conditions in step B of this modified method are the same as those in step B of the above-described method. It should be noted that, in this modified example, similarly to the above method, a second gas with a second flow rate greater than the first flow rate and a second flow velocity greater than the first flow velocity can be supplied to the wafer 200. The second flow rate in this modified example also includes the flow rate at the point in time when the flow rate is at its maximum immediately after valve 242b opens. Similarly, the second flow velocity in this modified example also includes the flow velocity at the point in time when the flow velocity is at its maximum immediately after valve 242b opens.

[0126] [Step F] After the second layer is formed on the surface within the recess of wafer 200 (after step B), in step F, with valves 243b and 242b open, the second gas flows into the gas supply pipe 232b. The example in Modified Example 1 where valve 243b is opened (in a closed state) in step F to supply the second gas from storage tank 240b to processing chamber 201 has been described. However, in this modified example, valve 243b is already open in step B, so it is not necessary to open valve 243b in step F. Apart from this, the processing steps and conditions in step F of this modified example are the same as in Modified Example 1. It should be noted that, similarly to Modified Example 1, in this modified example, at the start of step F, the opening of APC valve 244 is adjusted from a fully open state to a state between fully open and fully closed, that is, the opening is adjusted to bring the pressure in processing chamber 201 to a predetermined processing pressure.

[0127] It should be noted that, in this modified example, the execution period of step B can be understood as the period from the opening of valve 242b until the opening degree of APC valve 244 is adjusted from its previous state. Alternatively, in this modified example, the execution period of step B can also be understood as the period from the opening of valve 242b until the flow rate or velocity of the second gas reaches a substantially constant and stable value. In this case, step F can also be understood as the period from the point when the flow rate or velocity of the second gas reaches a substantially constant and stable value until valve 242b closes.

[0128] After step F, the opening of APC valve 244 is adjusted from a state between fully open and fully closed to a substantially fully open state (second opening). Then, the processing chamber 201 is purged using the same processing steps and conditions as in steps D+E. Then, the processing chamber 201 is evacuated using the same processing steps and conditions as in steps D+E.

[0129] The same effect as described above can be achieved in this modified example. In this modified example, the step coverage of the membrane can be further improved. In addition, by adjusting the supply time and flow rate of the second gas in step F, the step coverage and membrane quality can be controlled.

[0130] Furthermore, in this modified example, by performing step F without purging and vacuum exhaust after step B, productivity can be improved.

[0131] (Variation Example 3) In this modified example, the processing sequence can also be modified by performing the following (g) cycle, in addition to steps A, B, C, etc., a predetermined number of times, thereby forming a film containing the first element, the second element, and the metal element on the wafer 200: (g) Step G, which involves supplying a fourth gas containing a metal element to the wafer 200 after step B and before step C.

[0132] [Step G] A fourth gas containing metallic elements is supplied to the wafer 200 within the processing chamber 201. Specifically, valve 243d is opened, allowing the fourth gas to flow into the gas supply pipe 232d. At this time, the opening of APC valve 244 is reduced from its fully open state (second opening). Specifically, the opening of APC valve 244 is adjusted to a state between fully open and fully closed, that is, the opening is adjusted to achieve the desired processing pressure within the processing chamber 201.

[0133] It should be noted that the purging and vacuum exhaust steps in the processing chamber 201 can be performed between step B and step G, or they can be omitted. However, if step G is performed after step B, in order to set the period for adjusting the pressure in the processing chamber 201, it is preferable to perform the purging and vacuum exhaust steps in the processing chamber 201 between step B and step G.

[0134] Furthermore, if step F is performed after step B, as in variant example 1 or 2, step G is preferably performed after step F. In this case, the steps of purging and vacuum exhausting the processing chamber 201 can be performed between step F and step G, or they can be omitted.

[0135] By supplying a fourth gas containing metal elements (specifically, a raw material gas containing metal elements) to the wafer 200, it is possible to add (dop) metal elements to the second layer formed on the surface within the recess.

[0136] When the metal element is aluminum (Al), as the fourth gas, a gas containing at least one of aluminum trifluoride (AlF3), aluminum trichloride (AlCl3), etc. can be used.

[0137] After doping the second layer of metal elements into the surface formed within the recess of wafer 200, valve 243d is closed to stop supplying the fourth gas into processing chamber 201. Then, processing chamber 201 is purged using the same processing steps and conditions as in steps D+E. Then, vacuum is evacuated from processing chamber 201 using the same processing steps and conditions as in steps D+E. At this time, the opening of APC valve 244 is set to substantially fully open (second opening).

[0138] The same effect as described above can be achieved in this modified example. Furthermore, in this modified example, it is possible to form a film that further contains metallic elements (a doped film).

[0139] <Other aspects of the invention> The present invention has been specifically described above. However, the present invention is not limited to the above-described manner, and various modifications can be made without departing from its spirit.

[0140] Although not specifically described above, in step B, the release of the second gas from the storage tank 240b can also be stopped while the second gas remains in the storage tank 240b. The same effect as described above can be achieved in this method. Furthermore, in this method, by stopping the release of the second gas when the gas pressure inside the storage tank 240b is high, flash supply can be performed only during periods of high flow rate of the second gas.

[0141] Furthermore, the above method exemplifies the case where the first element contained in the first gas is Si. As for the second gas, a feed gas containing Si as the first element has been cited as an example. However, the first element can also be, for example, metallic elements such as titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), niobium (Nb), aluminum (Al), molybdenum (Mo), tungsten (W), and germanium (Ge). In this case, a nitride film containing these metallic elements is formed as the resulting film. The same effect as the method described above can be obtained in this method. Furthermore, in the above method, a reaction gas (nitriding agent) containing nitrogen as the second element was cited as an example of the third gas. However, for example, a reaction gas (oxidizing agent) containing oxygen as the second element can be used as the third gas. For example, a gas containing oxygen (O2), ozone (O3), nitrous oxide (N2O), nitric oxide (NO), nitrogen dioxide (NO2), carbon monoxide (CO), carbon dioxide (CO2), water vapor (H2O), hydrogen peroxide (H2O2), a mixture of H2 and O2, or a mixture of H2 and O3 can be used. In this case, a substance containing deuterium (D) can be used instead of a substance containing H. Deuterium (D2) can also be used as a substance containing D. When using a reaction gas containing oxygen as the third gas, an oxide film containing the aforementioned first element is formed as the resulting film. The same effect as the method described above can be obtained in this method.

[0142] The process for each process is preferably prepared separately according to the processing content, and recorded and stored in the storage device 121c via an electrical communication line and an external storage device 123. Furthermore, when starting each process, the CPU 121a preferably selects an appropriate process from the multiple processes recorded and stored in the storage device 121c according to the processing content. This allows for the reproducible formation of films of various types, compositions, qualities, and thicknesses using a single substrate processing device. Additionally, it reduces the operator's workload, enabling rapid initiation of each process while minimizing operational errors.

[0143] The aforementioned process is not limited to the case of new fabrication; for example, it can also be prepared by modifying an existing process already installed in the substrate processing apparatus. In the case of process modification, the modified process can also be installed in the substrate processing apparatus via an electrical communication line and a recording medium containing the process. Alternatively, the existing process already installed in the substrate processing apparatus can be directly modified by operating the input / output device 122 of the existing substrate processing apparatus.

[0144] This invention is not limited to the methods described above. For example, it can also be suitably applied to the formation of films using a monolithic substrate processing apparatus that processes one or more substrates at a time. Furthermore, this invention is not limited to the methods described above; it can also be suitably applied to the formation of films using a substrate processing apparatus with a cold-wall type processing furnace. When using these substrate processing apparatuses, each processing step and processing condition can be performed in the same manner and under the same conditions as described above, and the same effects as described above can be obtained.

[0145] The above methods and variations can be used in appropriate combinations. The processing steps and conditions can be set to be the same as those in the above methods and variations.

Claims

1. A substrate processing method, wherein, A film containing element 1 and element 2 is formed on a substrate by performing a predetermined number of cycles including the following steps: (a) A process of supplying a first gas containing a first element and a first halogen element to a substrate at a first flow rate; (b) A process of supplying the substrate with a second gas containing the first element and different from the first gas at a second flow rate greater than the first flow rate; and (c) A process following (b) of supplying the substrate with a third gas containing the second element.

2. The substrate processing method as described in claim 1, wherein, In (a), the first gas at a first flow rate is supplied to the substrate at the first flow velocity. In (b), the second gas, which has a second flow rate greater than the first flow rate, is supplied to the substrate at the second flow rate.

3. The substrate processing method as described in claim 1 or 2, wherein, The second gas is supplied to the substrate in such a manner that the second gas described in (b) remains in the space in which the substrate exists for a shorter time than the first gas described in (a) remains in the space in which the substrate exists.

4. The substrate processing method according to any one of claims 1 to 3, wherein, The exhaust velocity of the space in which the substrate exists in (b) is greater than the exhaust velocity of the space in (a).

5. The substrate processing method as described in claim 4, wherein, In (b), the opening degree of the valve of the exhaust path for venting the space where the substrate exists is set to a second opening degree, which is greater than the first opening degree, which is the valve opening degree in (a).

6. The substrate processing method as described in claim 5, wherein, The cycle also includes (d) a process, between (a) and (b), of changing the valve opening from the first opening to the second opening while the supply of the first gas is stopped.

7. The substrate processing method according to any one of claims 1 to 6, wherein, In (b), the second gas is supplied to the substrate when the pressure in the space where the substrate exists is a second pressure that is lower than the first pressure in the space where the substrate exists in (a).

8. The substrate processing method as described in claim 7, wherein, The cycle further includes (e) a step between (a) and (b) of changing the pressure of the space in which the substrate exists from the first pressure to the second pressure while the supply of the first gas is stopped.

9. The substrate processing method according to any one of claims 1 to 8, wherein, The thermal decomposition temperature of the second gas is lower than that of the first gas.

10. The substrate processing method according to any one of claims 1 to 9, wherein, The first gas is a gas that does not contain bonds between atoms of the first element, and the second gas is a gas that contains bonds between atoms of the first element.

11. The substrate processing method according to any one of claims 1 to 10, wherein, The second gas is a gas that further contains a second halogen element.

12. The substrate processing method according to any one of claims 1 to 11, wherein, In the loop, (a) begins before (b).

13. The substrate processing method as described in claim 12, wherein, In the loop, (b) begins after (a) ends.

14. The substrate processing method according to any one of claims 1 to 13, wherein, The cycle further includes (f) a step of supplying the second gas to the substrate at a third flow rate less than the second flow rate and for a period longer than (b) after (b) and before (c).

15. The substrate processing method according to any one of claims 1 to 14, wherein, The execution time of (a) is longer than that of (b).

16. The substrate processing method according to any one of claims 1 to 15, wherein, In (b), by opening the downstream valve of the gas storage section, the second gas, which is pressurized in the gas storage section constituting the supply system of the second gas, is supplied to the substrate.

17. The substrate processing method according to any one of claims 1 to 16, wherein, The cycle further includes (g) a step of supplying the substrate with a fourth gas containing a metal element after (b) and before (c). The membrane contains the metal element.

18. A method for manufacturing semiconductor devices, wherein, A film containing element 1 and element 2 is formed on a substrate by performing a predetermined number of cycles including the following steps: (a) A process of supplying a first gas containing a first element and a first halogen element to a substrate at a first flow rate; (b) A process of supplying the substrate with a second gas containing the first element and different from the first gas at a second flow rate greater than the first flow rate; and (c) A process following (b) of supplying the substrate with a third gas containing the second element.

19. A process product which, via a computer, causes a substrate processing apparatus to perform the step of forming a film comprising an element 1 and an element 2 on a substrate by performing the following cycles a predetermined number of times, said cycles comprising: (a) The step of supplying a first gas containing a first element and a first halogen element to a substrate at a first flow rate; (b) The step of supplying the substrate with a second gas containing the first element and different from the first gas at a second flow rate greater than the first flow rate; and (c) Following (b), the step of supplying the substrate with a third gas containing the second element.

20. A substrate processing apparatus, comprising: A gas supply system that supplies a substrate with a first gas containing a first element and a first halogen element, a second gas containing the first element but different from the first gas, and a third gas containing the second element; and A control unit, configured to control the gas supply system, performs a process of forming a film containing the first element and the second element on the substrate by performing the following cycle a predetermined number of times, the cycle including: (a) The process of supplying the first gas to the substrate at a first flow rate; (b) A process of supplying the second gas to the substrate at a second flow rate greater than the first flow rate; and (c) Following (b), the substrate is supplied with the third gas.

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