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

Abstract

This invention provides a technology that can improve the film deposition efficiency in a film deposition process that includes the step of supplying a reactant to a substrate. [Solution] The method includes a step of forming a film on a substrate by performing a predetermined number of cycles that include (a) supplying a first reactant that reacts with the surface of the substrate to the substrate at a first partial pressure, and (b) after (a), evacuating the processing space of the substrate so that the partial pressure of the reaction product produced by the reaction between the surface of the substrate and the first reactant present in the processing space of the substrate becomes a second partial pressure, wherein (a) and (b) are performed such that the ratio of the second partial pressure to the first partial pressure is less than or equal to a predetermined partial pressure ratio.

Description

[Technical Field]

[0001] This disclosure relates to a substrate processing method, a semiconductor device manufacturing method, a program, and a substrate processing apparatus. [Background technology]

[0002] As part of the manufacturing process for semiconductor devices, a cycle is sometimes performed that includes supplying a reactant such as a nitrogen-containing gas to a substrate to form a film such as a nitride film on the surface of the substrate (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2017-168644 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] This disclosure provides a technology that can improve the film deposition efficiency in a film deposition process that includes a step of supplying a reactant to a substrate. [Means for solving the problem]

[0005] According to one aspect of this disclosure, (a) A step of supplying a first reactant that reacts with the surface of the substrate to the substrate at a first partial pressure, (b) After (a), the process is to evacuate the processing space of the substrate so that the partial pressure of the reaction product produced by the reaction between the surface of the substrate and the first reactant, which is present in the processing space of the substrate, becomes the second partial pressure. The process includes a step of forming a film on the substrate by performing a predetermined number of cycles including the following: (a) and (b) are performed such that the first and second partial pressures are set such that the ratio of the second partial pressure to the first partial pressure is less than or equal to a predetermined partial pressure ratio. Technology is provided.

Advantages of the Invention

[0006] According to the present disclosure, in a film-forming process including a step of supplying a reactant to a substrate, it becomes possible to improve the film-forming efficiency.

Brief Description of the Drawings

[0007] [Figure 1] FIG. 1 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferably used in one aspect of the present disclosure, and is a diagram showing the processing furnace portion in a longitudinal sectional view. [Figure 2] FIG. 2 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferably used in one aspect of the present disclosure, and is a diagram showing the processing furnace portion in a sectional view taken along line A-A in FIG. 1. [Figure 3] FIG. 3 is a schematic configuration diagram of a controller of a substrate processing apparatus preferably used in one aspect of the present disclosure, and is a diagram showing a control system of the controller in a block diagram. [Figure 4] FIG. 4 is a diagram showing a substrate processing step in one aspect of the present disclosure. [Figure 5] FIG. 5 is a diagram for explaining a reaction on a substrate by supplying a reaction gas. [Figure 6] FIG. 6 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus in another aspect of the present disclosure, and is a diagram showing the processing furnace portion in a longitudinal sectional view. [Figure 7] FIG. 7 is a diagram showing a substrate processing step in another aspect of the present disclosure.

Embodiments for Carrying Out the Invention

[0008] <One Aspect of the Present Disclosure> Hereinafter, one aspect of the present disclosure will be mainly described while referring mainly to FIGS. 1 to 5. Note that the drawings used in the following description are all schematic, and the dimensional relationships and ratios of the respective elements shown in the drawings do not necessarily match the actual ones. Also, the dimensional relationships and ratios of the respective elements do not necessarily match among the plurality of drawings.

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

[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, for example, and is formed in a cylindrical shape with the upper end closed and the lower end open. Below the reaction tube 203, a manifold 209 is arranged concentrically with the reaction tube 203. The upper end of the manifold 209 is engaged with the lower end of the reaction tube 203 and is configured to support the reaction tube 203. An O-ring 220a as a seal member is provided between the manifold 209 and the reaction tube 203. Mainly, the reaction tube 203 and the manifold 209 constitute a processing container (reaction container). A processing chamber 201, which is a processing space, is formed in the cylindrical hollow portion of the processing container. The processing chamber 201 is configured to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed in this processing chamber 201.

[0011] In the processing chamber 201, nozzles 249a and 249b are provided so as to penetrate the side wall of the manifold 209. Gas supply pipes (pipes) 232a and 232b are respectively connected to the nozzles 249a and 249b.

[0012] On the gas supply pipes 232a and 232b, mass flow controllers (MFCs) 241a and 241b, which are flow controllers (flow control units), and valves 243a and 243b, which are on-off valves, are respectively provided in order from the upstream side. On the downstream side of the valves 243a and 243b of the gas supply pipes 232a and 232b, gas supply pipes 232c and 232d for supplying inert gas are respectively connected. On the gas supply pipes 232c and 232d, MFCs 241c and 241d and valves 243c and 243d are respectively provided in order from the upstream side.

[0013] As shown in Figure 2, nozzles 249a and 249b are provided in an annular space in plan view between the inner wall of the reaction tube 203 and the wafer 200, extending upward in the direction of wafer 200 stacking, along the upper part of the inner wall of the reaction tube 203 from the lower part. Gas supply holes 250a and 250b, which are supply ports for supplying gas, are provided on the sides of nozzles 249a and 249b, respectively. Multiple gas supply holes 250a and 250b are provided extending from the lower to the upper part of the reaction tube 203.

[0014] From the gas supply pipe 232a, a raw material gas containing a predetermined element is supplied into the processing chamber 201 via the MFC 241a, valve 243a, and nozzle 249a.

[0015] From the gas supply pipe 232b, a reaction gas, which acts as a first reactant that reacts with the raw material gas, is supplied into the processing chamber 201 via the MFC 241b, valve 243b, and nozzle 249b.

[0016] In this disclosure, the raw material gas can also be described as a second reactant that reacts with the first reactant.

[0017] Inert gas is supplied from gas supply pipes 232c and 232d into the processing chamber 201 via MFCs 241c and 241d, valves 243c and 243d, gas supply pipes 232a and 232b, nozzles 249a and 249b, respectively. When the inert gas supplied from gas supply pipes 232c and 232d is supplied simultaneously with the raw material gas or reaction gas, it is used as a diluent gas to dilute the raw material gas or reaction gas.

[0018] The raw material gas supply system (also called the second reactant supply system) mainly consists of gas supply pipes 232a, MFC 241a, and valve 243a. The reaction gas supply system (also called the first reactant supply system) mainly consists of gas supply pipes 232b, MFC 241b, and valve 243b. The raw material gas supply system and the reaction gas supply system can together be called the gas supply system (also called the reactant supply system). In addition, the inert gas supply system mainly consists of gas supply pipes 232c, 232d, MFC 241c, 241d, and valves 243c, 243d. The inert gas supply system may also be included in the gas supply system.

[0019] Of the various supply systems described above, one or all of them may be configured as an integrated supply system 248, which is comprised of valves 243a to 243d and MFCs 241a to 241d, etc. The integrated supply system 248 is connected to each of the gas supply pipes 232a to 232d, and the supply operation of various gases into the gas supply pipes 232a to 232d, i.e., the opening and closing operation of valves 243a to 243d and the flow rate adjustment operation by MFCs 241a to 241d, etc., is controlled by a controller 121, which will be described later. The integrated supply system 248 is configured as an integrated or segmented integrated unit, and can be attached to and detached from the gas supply pipes 232a to 232d, etc., in units of the integrated unit, and is configured so that maintenance, replacement, and expansion of the integrated supply system 248 can be performed in units of the integrated unit.

[0020] The reaction tube 203 is provided with an exhaust pipe 231 for exhausting the atmosphere inside the processing chamber 201. A vacuum pump 246, acting as a vacuum evacuation device, is connected to the exhaust pipe 231 via a pressure sensor 245, which acts 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 acts as a pressure regulator (pressure adjustment unit). The APC valve 244 can be opened and closed while the vacuum pump 246 is operating to perform vacuum evacuation and stop vacuum evacuation from the processing chamber 201. Furthermore, while the vacuum pump 246 is operating, the valve opening can be adjusted based on the pressure information detected by the pressure sensor 245 to adjust the pressure inside the processing chamber 201. 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.

[0021] Below the manifold 209, a seal cap 219 is provided, which serves as a furnace opening cover capable of airtightly closing the lower end opening of the manifold 209. An O-ring 220b is provided on the upper surface of the seal cap 219, which serves as a sealing member that contacts the lower end of the manifold 209. Below the seal cap 219, a rotating mechanism 267 is installed for rotating the boat 217, which will be described later. The rotating shaft 255 of the rotating mechanism 267 passes through the seal cap 219 and is connected to the boat 217. The rotating mechanism 267 is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be raised and lowered vertically by a boat elevator 115, which serves as a lifting mechanism installed outside the reaction tube 203. The boat elevator 115 is configured to move the boat 217 in and out of the processing chamber 201 by raising and lowering the seal cap 219. The boat elevator 115 is configured as a transport device (transport mechanism) for transporting the boat 217, i.e., the wafer 200, to and from the processing chamber 201.

[0022] The boat 217, which serves as a substrate support, is configured to support multiple wafers 200, for example 25 to 200 wafers 200, in a horizontal position and aligned vertically with their centers aligned, in multiple layers, that is, arranged with spacing between them. The boat 217 is made of a heat-resistant material such as quartz. Below the boat 217, multiple layers of heat-insulating plates 218, also made of a heat-resistant material such as quartz, are supported.

[0023] A temperature sensor 263 is installed inside the reaction tube 203 to detect temperature. By adjusting the power supply to the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature inside the processing chamber 201 can be adjusted to the desired temperature distribution.

[0024] As shown in Figure 3, the controller 121, which is the control unit (control means), is configured as a computer equipped with a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, storage device 121c, and 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, configured as, for example, a touch panel, is connected to the controller 121.

[0025] The storage device 121c is composed of, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. The storage device 121c contains, in a readable format, control programs that control the operation of the substrate processing device, and process recipes that describe the procedures and conditions for the film deposition process described later. The process recipe is a combination of steps in the film deposition process described later that can be executed by the controller 121 to obtain a predetermined result, and functions as a program. Hereinafter, process recipes and control programs will be collectively referred to simply as "programs" (program products). Similarly, process recipes will be simply referred to as "recipes." In this specification, the term "program" may include only recipes, only control programs, or both. RAM 121b is configured as a memory area (work area) where programs and data read by the CPU 121a are temporarily held.

[0026] I / O port 121d is connected to the MFCs 241a to 241d, valves 243a to 243d, pressure sensor 245, APC valve 244, vacuum pump 246, heater 207, temperature sensor 263, rotary mechanism 267, boat elevator 115, etc.

[0027] The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read a recipe from the storage device 121c in response to input of operation commands from the input / output device 122. The CPU 121a is configured to control the flow rate adjustment operation of various gases by the MFCs 241a to 241d, the opening and closing operation of valves 243a to 243d, the opening and closing operation of the APC valve 244 and the pressure adjustment operation of the APC valve 244 based on the pressure sensor 245, the starting and stopping of the vacuum pump 246, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the rotation and rotation speed adjustment operation of the boat 217 by the rotating mechanism 267, and the raising and lowering operation of the boat 217 by the boat elevator 115, in accordance with the contents of the read recipe.

[0028] The controller 121 can be configured by installing the above-mentioned program, which is recorded and stored on an external storage device (for example, a magnetic disk such as a hard disk, an optical disk such as a CD, or a semiconductor memory such as a USB memory) 123, into a computer. The storage device 121c and the external storage device 123 are configured as computer-readable recording media. Hereinafter, these will be collectively referred to simply as recording media. In this specification, the term recording media may include only the storage device 121c, only the external storage device 123, or both. Note that the program may be provided to the computer using communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0029] (2) Substrate processing process Using the substrate processing apparatus described above, an example sequence for forming a film containing a predetermined element on a wafer 200 as one step in the substrate processing process of the semiconductor device manufacturing process will be explained with reference to Figures 4 and 5. In the following explanation, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

[0030] In this specification, the term "wafer" may refer to the wafer itself or to a laminate of a wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of the wafer" may refer to the surface of the wafer itself or to the surface of a predetermined layer formed on the wafer. In this specification, when it is stated that "a predetermined layer is formed on the wafer," it may mean that the predetermined layer is formed directly on the surface of the wafer itself or that the predetermined layer is formed on a layer already formed on the wafer. In this specification, the term "substrate" has the same meaning as when it is used with the term "wafer."

[0031] (Wafer delivery) Once multiple wafers 200 are loaded into the boat 217, as shown in Figure 1, the boat 217 supporting the multiple wafers 200 is lifted by the boat elevator 115 and transported into the processing room 201.

[0032] (Pressure adjustment and temperature adjustment) The processing chamber 201, i.e., the space where the wafer 200 is located, is evacuated (reduced pressure exhausted) by a vacuum pump 246 so that it reaches a desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by a pressure sensor 245, and the APC valve 244 is feedback-controlled based on this measured pressure information. The vacuum pump 246 is kept running continuously at least until the processing of the wafer 200 is completed. The wafer 200 inside the processing chamber 201 is heated by a heater 207 so that it reaches a desired temperature. At this time, the amount of power supplied to the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the processing chamber 201 has a desired temperature distribution. Heating of the processing chamber 201 by the heater 207 is continued at least until the processing of the wafer 200 is completed. The rotation of the boat 217 and the wafer 200 by the rotation mechanism 267 is started. The rotation of the boat 217 and the wafer 200 by the rotating mechanism 267 continues at least until the processing of the wafer 200 is completed.

[0033] (Film deposition process) Then, perform steps S11 to S14 below.

[0034] [Raw material gas supply, step S11] First, a raw material gas, acting as the second reactant, is supplied to the wafer 200 in the processing chamber 201. Specifically, valve 243a is opened, and the raw material gas flows into the gas supply pipe 232a. The flow rate of the raw material gas is regulated by MFC 241a and supplied into the processing chamber 201 via nozzle 249a, and exhausted through exhaust pipe 231. At the same time, valve 243c is opened, and an inert gas flows into the gas supply pipe 232c. The flow rate of the inert gas is regulated by MFC 241c and supplied into the processing chamber 201 together with the raw material gas, and exhausted through exhaust pipe 231. Alternatively, to prevent the raw material gas from entering nozzle 249b, valve 243d may be opened, and the inert gas may flow into gas supply pipe 232d. The inert gas is supplied into the processing chamber 201 via gas supply pipe 232d and nozzle 249b, and exhausted through exhaust pipe 231.

[0035] The processing conditions in step S11 are: Processing temperature: 400-750°C, preferably 500-650°C Processing pressure (total pressure): 5 to 4000 Pa, preferably 10 to 1333 Pa Partial pressure of the raw material gas: 1 to 3000 Pa, preferably 5 to 1500 Pa Inert gas supply flow rate (total flow rate): 0 to 10,000 sccm, preferably 100 to 5,000 sccm Processing time: 0.1 to 240 seconds, preferably 1 to 120 seconds Examples are given.

[0036] Furthermore, it is preferable that the processing temperature be substantially the same in all of the following steps. In this specification, processing temperature refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201, and processing pressure refers to the pressure inside the processing chamber 201. Processing time refers to the time during which the processing is continued. These terms are also the same in the following explanation. In this specification, numerical range notations such as "400~750°C" mean that the lower and upper limits are included within that range. For example, "400~750°C" means "400°C or more and 750°C or less". The same applies to other numerical ranges. When the supply flow rate includes 0 sccm, 0 sccm means the case in which the substance (gas) is not supplied. This is also the same in the following explanation.

[0037] Under the processing conditions described above, a silicon (Si)-containing layer containing chlorine (Cl) is formed on the surface of the wafer 200 by supplying, for example, a chlorosilane-based gas as a raw material gas to the wafer 200. The Si-containing layer containing Cl is formed by physical or chemical adsorption of molecules of the chlorosilane-based gas onto the outermost surface of the wafer 200, or by physical or chemical adsorption of molecules of substances obtained by the decomposition of part of the chlorosilane-based gas. The Si-containing layer containing Cl may also be an adsorption layer (physical adsorption layer or chemical adsorption layer) of molecules of chlorosilane-based gas or molecules of substances obtained by the decomposition of part of the chlorosilane-based gas. In this specification, the Si-containing layer containing Cl is also simply referred to as the Si-containing layer. The Si-containing layer formed in this step is also simply referred to as the first layer.

[0038] A raw material gas containing a predetermined element can be used as the raw material gas. In particular, a raw material gas containing a predetermined element and a halogen element can be used as the raw material gas.

[0039] Examples of halogen elements that can be used include Cl, fluorine (F), bromine (Br), iodine (I), etc. One or more of these halogen elements can be used.

[0040] Examples of specified elements include metalloid elements such as Si, boron (B), germanium (Ge), arsenic (As), antimony (Sb), and tellurium (Te), as well as metallic elements such as titanium (Ti), aluminum (Al), tungsten (W), hafnium (Hf), zirconium (Zr), tantalum (Ta), molybdenum (Mo), ruthenium (Ru), and cobalt (Co).

[0041] As a raw material gas containing the specified elements, for example, a halosilane gas containing halogen elements and Si, an aminosilane gas containing an amino group and Si, or an inorganic silane gas containing Si can be used.

[0042] Examples of halosilane gases that can be used include chlorosilane gases such as dichlorosilane (SiH2Cl2) gas, trichlorosilane (SiHCl3) gas, tetrachlorosilane (SiCl4) gas, and hexachlorodisilane (Si2Cl6) gas; fluorosilane gases such as tetrafluorosilane (SiF4) gas and difluorosilane (SiH2F2) gas; bromosilane gases such as tetrabromosilane (SiBr4) gas and dibromosilane (SiH2Br2) gas; and iodosilane gases such as tetraiodosilane (SiI4) gas and diiodosilane (SiH2I2) gas. One or more of these can be used as the halosilane gas.

[0043] Examples of aminosilane gases that can be used include tetrakisdimethylaminosilane (Si[N(CH3)2]4) gas, trisdimethylaminosilane (Si[N(CH3)2]3H) gas, bisdiethylaminosilane (Si[N(C2H5)2]2H2) gas, bis-sharrybutylaminosilane (SiH2[NH(C4H9)]2) gas, and diisopropylaminosilane (SiH3[N(C3H7)2]) gas. One or more of these can be used as the aminosilane gas.

[0044] Examples of inorganic silane gases that can be used include monosilane (SiH4) gas, disilane (Si2H6) gas, and trisilane (Si3H8) gas. One or more of these can be used as the inorganic silane gas.

[0045] As the inert gas, for example, nitrogen (N2) gas or noble gases such as argon (Ar), helium (He), neon (Ne), and xenon (Xe) can be used. One or more of these can be used as the inert gas.

[0046] [Purge, Step S12] After a first layer containing a predetermined element is formed on at least a portion of the wafer 200, the valve 243a is closed to stop the supply of the raw material gas. At this time, the APC valve 244 is fully opened, and the processing chamber 201 is evacuated using the vacuum pump 246 to remove any unreacted raw material gas remaining in the processing chamber 201, as well as reaction products generated by the reaction between the raw material gas and the surface of the wafer 200.

[0047] At this time, it is desirable to keep valves 243c and 243d open to maintain the supply of inert gas into the treatment chamber 201. The inert gas acts as a purge gas.

[0048] In this specification, a reaction product that can produce a reaction (reverse reaction) in which a first layer formed on the surface of wafer 200 is desorbed from the surface of wafer 200 by reacting with the first layer formed on the surface of wafer 200 in response to a reaction (forward reaction) in which a source gas or a part of its molecules is adsorbed onto the surface of wafer 200 is sometimes referred to as reaction product A.

[0049] When a halosilane gas is used as the raw material gas, reaction product A may contain halogen elements present in the raw material gas (e.g., chlorine (Cl2) or hydrogen chloride (HCl)). When an aminosilane gas is used as the raw material gas, reaction product A may contain at least one of carbon (C), nitrogen (N), and hydrogen (H) present in the raw material gas (e.g., hydrogen (H2) gas or hydrocarbon compounds). When an inorganic silane gas is used as the raw material gas, reaction product A may contain H present in the raw material gas (e.g., H2 gas).

[0050] The processing conditions in step S12 are: Processing pressure (purge pressure) (total pressure): 0.1 to 1330 Pa, preferably 1 to 400 Pa Inert gas supply flow rate (total flow rate): 0 to 10,000 sccm, preferably 100 to 5,000 sccm Processing time (purging time): 0.1 to 120 seconds, preferably 0.1 to 60 seconds This is an example. Other processing conditions can be the same as the processing conditions in step S11.

[0051] [Reaction gas supply, step S13] Next, a reaction gas, acting as a first reactant, is supplied at a first partial pressure to the wafer 200 in the processing chamber 201, reacting with the first layer, which is the surface (or outermost surface) of the wafer 200. Specifically, valve 243b is opened, and the reaction gas flows into the gas supply pipe 232b. The reaction gas flow rate is regulated by MFC 241b and supplied into the processing chamber 201 via nozzle 249b, and exhausted through exhaust pipe 231. At the same time, valve 243d is opened, and inert gas flows into the gas supply pipe 232d. The inert gas flow rate is regulated by MFC 241d and supplied into the processing chamber 201 together with the reaction gas, and exhausted through exhaust pipe 231. In addition, to prevent the reaction gas from entering nozzle 249a, valve 243c is opened, and inert gas flows into gas supply pipe 232c. The inert gas is supplied into the processing chamber 201 via the gas supply pipe 232c and nozzle 249a, and exhausted through the exhaust pipe 231.

[0052] The processing conditions in step S13 are: Processing pressure (total pressure): 1013 to 506625 Pa, preferably 10133 to 101325 Pa Partial pressure of reaction gas (first partial pressure): 10¹³ to 506625 Pa, preferably 10¹³³ to 10¹³² Pa Inert gas supply flow rate (total flow rate): 0 to 5000 sccm, preferably 50 to 2500 sccm Processing time: 1 to 180 seconds, preferably 10 to 60 seconds This is an example. Other processing conditions can be the same as the processing conditions in step S11.

[0053] In this step, at least one of the inert gas supply flow rate and partial pressure is set lower than at least one of the inert gas supply flow rate and partial pressure in steps S11 and S12 described above and step S14 described later. This makes it possible to increase the partial pressure of the reaction gas supplied into the processing chamber 201 in this step, thereby increasing the pressure difference with the partial pressure of the reaction product in the next step S14. Alternatively, for example, in this step, the inert gas may not be supplied into the processing chamber 201 at all, and the partial pressure of the reaction gas supplied to the wafer 200 may be increased.

[0054] By supplying a reaction gas to the wafer 200 under the conditions described above, at least a portion of the first layer formed on the wafer 200 is modified. If, for example, a hydrogen nitride-based gas containing N and H is used as the reaction gas, at least a portion of the first layer formed on the wafer 200 is nitrided, and a silicon nitride layer (SiN layer) containing Si and N is formed on the outermost surface of the wafer 200. The SiN layer formed in this step is also simply referred to as the second layer.

[0055] As the reaction gas, for example, a nitride agent can be used. As the nitride agent (nitriding gas), for example, a gas containing nitrogen (N) and hydrogen (H) can be used. As the N and H-containing gas, for example, hydrogen nitride-based gases such as ammonia (NH3) gas, diazene (N2H2) gas, hydrazine (N2H4) gas, and triazane (N3H5) gas can be used. One or more of these can be used as the nitride agent. In this step, if a nitride agent is used as the reaction gas, the first layer is nitrided to modify it into a nitrided layer.

[0056] Furthermore, an oxidizing agent can be used as the reaction gas. For example, oxygen (O) and H-containing gases can be used as the oxidizing agent (oxidizing gas). Examples of O and H-containing gases include water vapor (H2O gas), hydrogen peroxide (H2O2) gas, a mixture of hydrogen (H2) gas and oxygen (O2) gas, a mixture of H2 gas and ozone (O3) gas, etc. In addition to O and H-containing gases, an oxygen (O)-containing gas can also be used as the oxidizing agent. Examples of O-containing gases include O2 gas, O3 gas, nitrous oxide (N2O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, carbon monoxide (CO) gas, carbon dioxide (CO2) gas, etc. Note that O and H-containing gases are also a type of O-containing gas. One or more of these can be used as the oxidizing agent. In this step, when an oxidizing agent is used as the reaction gas, the first layer is oxidized and modified into an oxidized layer.

[0057] As used herein, the term "agent" includes at least one of gaseous substances and liquid substances. Liquid substances include mist-like substances. That is, nitriding agents and oxidizing agents may contain gaseous substances, liquid substances such as mist-like substances, or both.

[0058] [Purge, Step S14] After step S13 is completed, residual gas in the processing chamber 201 is removed. Specifically, after at least a portion of the first layer on the wafer 200 has been modified into the second layer, valve 243b is closed to stop the supply of reaction gas. At this time, APC valve 244 is fully opened and the processing chamber 201 is evacuated using vacuum pump 246 to remove any unreacted reaction gas remaining in the processing chamber 201, as well as reaction products generated by the reaction between the reaction gas and the surface of the wafer 200 (i.e., the surface of the first layer). At this time, valves 243c and 243d are left open to maintain the supply of inert gas to the processing chamber 201. The inert gas acts as a purge gas.

[0059] In this specification, a reaction product that can cause a reaction (reverse reaction) to return the second layer to its state before the modification reaction (forward reaction) by reacting with the surface of the modified wafer 200 (i.e., the surface of the second layer) in response to a modification reaction (forward reaction) caused by the reaction of the surface of the wafer 200 (i.e., the surface of the first layer) with a reaction gas is sometimes referred to as reaction product B.

[0060] Forward reforming reactions include, for example, nitriding and oxidation reactions of the first layer, and elimination reactions that remove impurities such as halogen elements and H from the first layer. On the other hand, reverse reactions include, for example, reactions that remove N from the second layer after nitriding, reactions that remove O from the second layer after oxidation, and reactions in which impurities are reincorporated into the second layer after impurity removal.

[0061] When a halosilane-based gas is used as the raw material gas and a hydrogen nitride-based gas is used as the reaction gas, the reaction product B may contain a substance containing a halogen element and H (e.g., hydrogen chloride (HCl)) or a substance containing H contained in the reaction gas (e.g., H2 gas). When an aminosilane-based gas is used as the raw material gas and a hydrogen nitride-based gas is used as the reaction gas, the reaction product B may contain a substance containing at least one of C, N, and H (e.g., hydrogen (H2) gas or hydrocarbon compounds). When an inorganic silane-based gas is used as the raw material gas and a hydrogen nitride-based gas is used as the reaction gas, the reaction product B may contain a substance containing H (e.g., H2 gas).

[0062] In this step, the processing chamber 201 is evacuated using a vacuum pump 246 to reduce the partial pressure of the reaction product B, which is produced by the reaction between the surface of the wafer 200 and the reaction gas, to the second partial pressure or lower. At the same time, an inert gas is supplied to the processing chamber 201 as a purge gas to further promote the reduction of the partial pressure of the reaction product B present in the processing chamber 201.

[0063] The processing conditions in step S14 are: Processing pressure (purge pressure) (total pressure): 0.001 to 10 Pa, preferably 0.01 to 1 Pa Inert gas supply flow rate (total flow rate): 0 to 10,000 sccm, preferably 100 to 5,000 sccm Processing time: 1 to 240 seconds, preferably 2 to 180 seconds This is an example. Other processing conditions can be the same as the processing conditions in step S11.

[0064] The dashed line in Figure 4 is an illustrative diagram showing the change in the partial pressure of the reaction gas in the processing chamber 201, and the dashed line in Figure 4 is an illustrative diagram showing the change in the partial pressure of the reaction product B in the processing chamber 201. Reaction product B is generated by the supply of reaction gas in step S13 described above, and in step S14, these reaction product B are removed. Here, the difference (also called differential pressure) between the partial pressure of the reaction gas at the time of reaction gas supply in step S13 (first partial pressure) and the partial pressure of reaction product B in the processing chamber 201 in step S14 (second partial pressure) is set to be greater than or equal to a predetermined value. Then, in step S14, the state in which the partial pressure of reaction product B in the processing chamber 201 is less than or equal to the second partial pressure is maintained for a predetermined period (period T2). Here, the predetermined value of the differential pressure can be a value in which the partial pressure of reaction product B in the processing chamber 201 in step S14, relative to the partial pressure of reaction product B in the processing chamber 201 in step S13, is the first partial pressure ratio as a predetermined partial pressure ratio described later.

[0065] Furthermore, when multiple substances (e.g., HCl and H2) are produced as reaction product B, the "partial pressure of reaction product B" as used herein may refer to the partial pressure of each of the multiple substances that make up reaction product B. The sum of the partial pressures of the multiple substances that make up reaction product B can also be considered as the partial pressure of reaction product B.

[0066] Furthermore, in this embodiment, steps S13 and S14 described above can be carried out such that the ratio of the second partial pressure, which is the partial pressure of reaction product B in step S14, to the first partial pressure, which is the partial pressure of the reaction gas in step S13, is less than or equal to a predetermined partial pressure ratio, which is the first partial pressure ratio.

[0067] Furthermore, steps S13 and S14 can be carried out such that the ratio of the pressure (total pressure) in the processing chamber 201 in step S14 to the first partial pressure, which is the partial pressure of the reaction gas in step S13, is less than or equal to the first partial pressure ratio. Specifically, for example, the ratio of the pressure (total pressure) in the processing chamber 201 in step S14 to the partial pressure of the reaction gas in step S13 is 10 -7 ~10 -4Preferably 10 -6 ~10 -5 Steps S13 and S14 can be performed in such a manner. In this configuration, if multiple reaction products B (e.g., HCl and H2) are present in the processing chamber 201, steps S13 and S14 can be performed in such a manner that the ratio of the sum of the partial pressures of the multiple reaction products B in step S14 to the partial pressure of the reaction gas in step S13 falls within the range described above. In this way, it becomes easy to adjust the pressure so that the ratio of the partial pressure of the reaction products in the processing chamber 201 in step S14 to the partial pressure of the reaction gas in step S13 is less than or equal to the first partial pressure ratio, without measuring the partial pressure of the reaction products.

[0068] In this step, the partial pressure of reaction product B present in the processing chamber 201 can be reduced to the second partial pressure by increasing the opening of a valve (i.e., APC valve 244, etc.) in the exhaust passage. Alternatively, in this step, the partial pressure of reaction product B present in the processing chamber 201 can be reduced to the second partial pressure by increasing the exhaust speed of the exhaust device (i.e., vacuum pump 246, etc.). Alternatively, in this step, the partial pressure of reaction product B present in the processing chamber 201 can be reduced to the second partial pressure by increasing the partial pressure of the inert gas supplied into the processing chamber 201.

[0069] Furthermore, in step S13, the difference between the first and second partial pressures can be made greater than or equal to a predetermined value by increasing the partial pressure of the reaction gas (first partial pressure). Similarly, in step S13, the ratio of the second partial pressure to the first partial pressure can be made less than or equal to the ratio of the first partial pressure by increasing the first partial pressure.

[0070] Here, if a gas containing N and H (for example, a hydrogen nitride-based gas such as NH3 gas) is used as the reaction gas, and a substance containing a halogen element (for example, a compound containing H and a halogen element such as HCl) is produced as the reaction product B (hereinafter referred to as the first combination), then the ratio of the second partial pressure to the first partial pressure is 10 -7 ~10 -4 Preferably 10-6 ~10 -5 Steps S13 and S14 are performed so as to obtain such a result. That is, in this case, the first partial pressure ratio is set to a value within this range. Note that the reaction product B in this specific example may be particularly referred to as the first reaction product B. When this ratio is less than 10 -7 it may be difficult to provide a reaction gas supply system and an exhaust system capable of realizing this ratio. When this ratio is less than 10 -6 it may be difficult to supply the reaction gas to the wafer 200 in an appropriate state because the first partial pressure is too high. When this ratio is less than 10 -6 by setting it to 10 or more, even when the first partial pressure is below atmospheric pressure, it becomes easy to realize this ratio by controlling the second partial pressure. When this ratio exceeds 10 -5 depending on other conditions such as the processing temperature, it may be difficult to make the value of the free energy of formation ΔGb (described later) in the reforming reaction that occurs in steps S13 and S14 negative. When this ratio is 10 -5 or less, it becomes easy to make the value of ΔGb negative. When this ratio exceeds 10 -4 depending on other conditions, it may be difficult to make the value of ΔGb negative without regard to other conditions.

[0071] Further, when a gas containing N and H (for example, a hydrogen nitride-based gas such as NH3) is used as the reaction gas and a substance containing H (for example, a simple substance of H such as H2) is generated as the reaction product B (hereinafter referred to as the second combination), the ratio of the second partial pressure to the first partial pressure is 10 -7 ~10 -3 preferably 10 -6 ~10 -4 Steps S13 and S14 are performed so as to obtain such a result. That is, in this case, the first partial pressure ratio is set to a value within this range. When this ratio is less than 10 -7 it may be difficult to provide a reaction gas supply system and an exhaust system capable of realizing this ratio. When this ratio is less than 10 -6 it may be difficult to supply the reaction gas to the wafer 200 in an appropriate state because the first partial pressure is too high. When this ratio is less than 10-6 By doing so, even when the first partial pressure is below atmospheric pressure, it becomes easy to achieve the ratio by controlling the second partial pressure. -4 When exceeding this value, it may be difficult to make the value of ΔGb negative depending on other conditions such as processing temperature. -4 By doing the following, it becomes easy to make the value of ΔGb negative. Set the ratio to 10 -3 When the value is set to "greater than," it can be difficult to make the value of ΔGb negative, regardless of other conditions.

[0072] To distinguish it from the first reaction product B in the first example of the combination described above, the reaction product B in the second example of the combination can be specifically referred to as the second reaction product B. The first reaction product B and the second reaction product B are different substances. Also, to distinguish it from the first partial pressure ratio corresponding to the first reaction product B described above, the first partial pressure ratio in the second example of the combination may be specifically referred to as the second partial pressure ratio (or the second predetermined partial pressure ratio). The first partial pressure ratio and the second partial pressure ratio can each be different values. Also, to distinguish it from the second partial pressure corresponding to the first reaction product B described above, the second partial pressure in this specific example may be specifically referred to as the third partial pressure. The second partial pressure and the third partial pressure can each be different values ​​so as to correspond to different first and second partial pressure ratios. For example, in this case, the third partial pressure can be 10 times the value of the second partial pressure.

[0073] In other words, the appropriate value to be set as the first partial pressure ratio, which is the ratio of the second or third partial pressure to the first partial pressure in steps S13 and S14, varies depending on the combination of the reaction gas and the reaction product B generated by the supply of the reaction gas, and a value can be set according to the combination. For example, the partial pressures of the reaction gas and reaction product B in each step are set to achieve the optimal pressure ratio according to the combination of the reaction gas and reaction product B. This makes it possible to set the partial pressure of the reaction gas in step S13 lower depending on the type of gas. Also, depending on the type of gas, the vacuum level in the processing chamber 201 in step S14 can be lowered. For example, if the partial pressure ratio of HCl as the reaction product B present in the processing chamber 201 is 10 -5 If the following conditions are met, the ratio of H2 partial pressures is 10 -4 The following conditions must be met.

[0074] According to the Disclosers' verification, it has been confirmed that increasing the difference between the partial pressure of the reaction gas in step S13 (first partial pressure) and the partial pressure of the reaction product B remaining in the processing chamber 201 (second partial pressure) promotes the modification reactions such as nitriding and oxidation of the film. Similarly, it has been confirmed that decreasing the ratio of the second partial pressure to the first partial pressure promotes these modification reactions.

[0075] In this disclosure, the value of the formation free energy ΔGb in the reaction between the first layer and the reaction gas can be made negative by setting the differential pressure between the first and second partial pressures to be greater than or equal to the predetermined value described above, or by setting the ratio of the second partial pressure to the first partial pressure to be less than or equal to the predetermined partial pressure ratio described above (i.e., the ratio of the first partial pressure). By providing conditions for a negative value of ΔGb, an exothermic reaction can be made to occur in the reaction between the first layer and the reaction gas.

[0076] In other words, the first partial pressure ratio, which is a predetermined partial pressure ratio in this embodiment, can be a ratio value such that the value of ΔGb is negative. To put it another way, the first partial pressure ratio can be a ratio in which an exothermic reaction occurs in the transition from the state before the reaction between the first layer and the reaction gas in step S13 to the state in step S14. In this way, by setting the first partial pressure ratio to a ratio in which an exothermic reaction occurs in the state transition, the reaction by supplying the reaction gas (i.e., the forward reaction described above) can be further promoted without raising the processing temperature.

[0077] Here, the atomic bonding on the surface of wafer 200 changes from the initial state to the final state due to the supply of the reaction gas. Figure 5(A) is an image of the surface of wafer 200 in the initial state before the supply of the reaction gas (i.e., the surface of the first layer), and Figure 5(B) is an image of the surface of wafer 200 in one of the final states after the supply of the reaction gas (i.e., the surface of the second layer). Figure 5(A) shows the state in which NH3 gas is supplied as the reaction gas to a layer containing Si and Cl as the first layer, and Figure 5(B) shows the state in which a layer containing Si and N as the second layer (i.e., the second layer) is formed and HCl is present as the reaction product B. In the process in which the atomic bonding changes from the initial state in Figure 5(A) to the final state in Figure 5(B), the system transitions to the transition state, which is the highest energy state among the energy states in the reaction system between the first layer and the reaction gas. The difference between the energy level (eV) in this transition state and the energy level (eV) in the initial state (before the reaction) is called the activation Gibbs energy ΔGa. Furthermore, the difference between the energy level (eV) of the final state (after the reaction) and the energy level (eV) of the initial state (before the reaction) is called the formation free energy ΔGb.

[0078] When ΔGb is positive, i.e., ΔGb > 0, the probability of a state transition from the final state to the initial state (i.e., the reverse reaction) occurring between the reaction product B, such as HCl or H2, and the second layer becomes relatively higher. In other words, the reforming reaction from the first layer to the second layer by the reaction gas becomes less likely to proceed, which can lead to a decrease in the efficiency of reforming reactions such as nitriding or oxidation, or even result in insufficient reforming.

[0079] Conversely, when ΔGb is negative, i.e., ΔGb < 0, the probability of the reverse reaction described above occurring is relatively reduced. In other words, the reforming reaction from the first layer to the second layer (forward reaction) by the reaction gas proceeds more easily, thereby improving the efficiency of the reforming reaction and suppressing insufficient reforming of the first layer. More specifically, by promoting the reforming reaction, the film deposition rate can be improved, as can the step coverage.

[0080] Table 1 below summarizes the simulation results obtained by calculating ΔGa and ΔGb under different conditions for the partial pressure (first partial pressure) of NH3, the reaction gas in step S13, and the partial pressure (second partial pressure) of HCl, the reaction product B in step S14. The surface of wafer 200 at the start of step S13 in this simulation was as shown in Figure 5(A).

[0081] [Table 1]

[0082] In Sample 1, when the first partial pressure is 101325 Pa and the second partial pressure is 100 Pa, ΔGa is 2.48 eV and ΔGb is 0.17 eV.

[0083] As Sample 2, when the first partial pressure is 101325 Pa and the second partial pressure is 1 Pa, ΔGa is 2.48 eV and ΔGb is -0.19 eV.

[0084] For Sample 3, when the first partial pressure is 100 Pa and the second partial pressure is 100 Pa, ΔGa is 3.03 eV and ΔGb is 0.72 eV.

[0085] For Sample 4, when the first partial pressure is 100 Pa and the second partial pressure is 1 Pa, ΔGa is 3.03 eV and ΔGb is 0.36 eV.

[0086] From Sample 2 in Table 1, it can be confirmed that the formation free energy ΔGb can be made negative by increasing the first partial pressure to, for example, atmospheric pressure and decreasing the second partial pressure to about 1 Pa. In other words, according to this simulation, the ratio of the partial pressure of reaction product B in step S14 to the partial pressure of the reaction gas in step S13 is 10 -5 By doing the following (i.e., the first partial pressure ratio is set to 10 -5 As shown above, it can be seen that ΔGb can be made negative. In other words, by making the partial pressure of the reaction gas in step S13 more than five orders of magnitude (more than 100,000 times) greater than the partial pressure of the reaction product B in step S14, ΔGb can be made negative. Note that the pressure (total pressure) inside the processing chamber 201 is greater than or equal to the magnitude of the partial pressure of the gas present inside it, so the ratio of the pressure inside the processing chamber 201 after depressurization in step S14 (i.e., the processing pressure in step S14) to the partial pressure of the reaction gas in step S13 is 10 -5 ΔGb can also be made negative by doing the following:

[0087] By using an H-containing gas such as NH3 gas as the reaction gas, a compound gas containing H different from that of the reaction gas (for example, a compound containing a halogen element such as HCl and H) or H2 gas is produced as the reaction product. When both the reaction gas and the reaction product contain H, the value of ΔGb in the reaction between the first layer and the reaction gas tends to be positive (i.e., the reverse reaction tends to occur). Therefore, in such cases, controlling the ratio of the second partial pressure to the first partial pressure to be less than or equal to the ratio of the first partial pressure (i.e., so that the value of ΔGb is negative), as in this embodiment, is particularly effective in promoting the reforming reaction.

[0088] In this step, as shown in Figure 4, the partial pressure of the reaction product in the processing chamber 201 is maintained at or below the second partial pressure for a predetermined period (period T2). In this step, period T2 is made longer than period T1, which is the period from when the reaction gas supply in step S13 is stopped until the partial pressure of the reaction product B in the processing chamber 201 reaches or below the second partial pressure. By shortening period T1, during which the reverse reaction to the reforming reaction is likely to occur, the occurrence of the reverse reaction in this step can be suppressed and the reforming reaction can be promoted.

[0089] Furthermore, the execution time of this step is made longer than the execution time of step S12. This makes it possible to sufficiently reduce the partial pressure of the reaction product in this step, and makes it easy to reduce the partial pressure of the reaction product to the first partial pressure ratio.

[0090] (Performed the prescribed number of times) The cycle including steps S11 to S14 described above is performed a predetermined number of times (n times, where n is 1 or an integer of 2 or more). As a result, a film containing a predetermined element and having a predetermined thickness is formed on the wafer 200. For example, when a gas containing Si as the predetermined element is used as the raw material gas and a nitride agent is used as the reaction gas, a silicon nitride film (SiN film) is formed as the film containing the predetermined element. Alternatively, for example, when a gas containing Si as the predetermined element is used as the raw material gas and an oxidizing agent is used as the reaction gas, a silicon oxide film (SiO film) is formed as the film containing the predetermined element.

[0091] (After-purge / atmospheric pressure return step) Inert gas is supplied into the processing chamber 201 from gas supply pipes 232c and 232d, respectively, and exhausted from exhaust pipe 231. This purges the processing chamber 201, after which the atmosphere inside the processing chamber 201 is replaced with inert gas, and the pressure inside the processing chamber 201 is returned to atmospheric pressure.

[0092] (Boat unloading and wafer discharge) The boat elevator 115 lowers the seal cap 219, opening the lower end of the manifold 209. The processed wafer 200, supported by the boat 217, is then transported out of the reaction tube 203 from the lower end of the manifold 209. The processed wafer 200 is removed from the boat 217.

[0093] <Other aspects of this disclosure> Next, other embodiments of the substrate processing apparatus described above will be explained with reference to Figures 6 and 7. In this embodiment, elements of the substrate processing apparatus that are substantially the same as those described in Figure 1 are denoted by the same reference numerals, and their descriptions are omitted.

[0094] In this embodiment, as shown in Figure 6, a valve 302, a tank 300 which is a storage section for storing gas, and a valve 304 are provided in order from the upstream side of the gas flow, downstream of valve 243b of the gas supply pipe 232b and downstream of the junction with gas supply pipe 232d. That is, the tank 300 and valves 302 and 304 are provided on the supply line of the reaction gas and the inert gas. The reaction gas supply system (also called the first reactant supply system) in this embodiment is mainly composed of the gas supply pipe 232b, MFC 241b, valve 243b, valve 302, tank 300, and valve 304. An inert gas supply system connected to the reaction gas supply system may also be included in the reaction gas supply system. Note that the storage section is not limited to being composed of tank 300, but may also be composed of gas supply pipe 232b which constitutes the section between valve 302 and valve 304.

[0095] Tank 300 is temporarily filled with the reaction gas supplied from gas supply pipe 232b and the inert gas supplied from gas supply pipe 232d by opening and closing the upstream valve 302 and the downstream valve 304. Inside tank 300, the reaction gas and the inert gas are mixed, and the reaction gas is diluted with the inert gas. At this time, the partial pressure of the reaction gas inside tank 300 is increased (i.e., it is pressurized). Then, the reaction gas that has been filled into tank 300, has had its partial pressure increased, and has been diluted with the inert gas is supplied to the wafer 200 in large quantities at once.

[0096] In this embodiment, in the reaction gas supply in step S13 of the substrate processing process of the embodiment described above, the reaction gas pressurized in the tank 300 is supplied to the wafer 200 in the processing chamber 201 using the tank 300 and valves 302 and 304, under substantially the same processing temperature.

[0097] Specifically, in step S13, during the reaction gas supply, valve 304 is closed in advance, and valves 243b, 243d, and 302 are opened to fill tank 300 with reaction gas and inert gas whose flow rates have been adjusted by MFCs 241b and 241d, respectively. Then, by opening valve 304, the mixed gas of reaction gas and inert gas, which has been filled into tank 300 and whose partial pressure has been increased, is supplied to the wafer 200 in large quantities at once. By supplying a large quantity of the reaction gas with increased partial pressure to the wafer 200 in large quantities at once, the first partial pressure can be increased, and the pressure difference with the partial pressure of the reaction product (second partial pressure) in the next step S14 can be increased. In addition, by supplying a large quantity of the reaction gas with increased partial pressure to the wafer 200 in large quantities at once, the first partial pressure can be increased, and the ratio of the second partial pressure to the first partial pressure can be decreased.

[0098] In this embodiment, the same effects as in the above-described embodiment can be obtained. Furthermore, in this embodiment, by increasing the partial pressure of the reaction gas in step S13, it becomes easier to reduce the ratio of the partial pressure of the reaction product in the next step S14 to the partial pressure of the reaction gas. That is, in this embodiment, it becomes easier to make the ratio of the second partial pressure to the first partial pressure less than or equal to the ratio of the first partial pressure. Therefore, modification reactions such as nitriding and oxidation can be promoted, and as a result, the film deposition rate is improved and step coverage is improved.

[0099] The above describes in detail one aspect of this disclosure. However, this disclosure is not limited to the aspect described above, and various modifications are possible without departing from its essence.

[0100] Furthermore, the raw material gas supply in step S11 and the purging in step S12 described above can be used in the same way as the reaction gas supply in step S13 and the purging in step S14 described above. That is, in steps S11 and S12, the same effect as in the above embodiment can be obtained by making sure that the ratio of the partial pressure of the reaction product (i.e., reaction product A) in the next step S12 to the partial pressure of the raw material gas in step S11 is less than or equal to a predetermined partial pressure ratio (which can also be called the third partial pressure ratio). For example, in step S11, by using a halosilane gas (e.g., a chlorosilane gas) as the raw material gas, a compound containing a halogen element may be produced as reaction product A. In this case, steps S11 and S12 are executed so that the ratio of the partial pressure of reaction product A (e.g., Cl2 or HCl) in step S12 to the partial pressure of the raw material gas in step S11 is less than or equal to the third partial pressure ratio. The third partial pressure ratio here, like the first partial pressure ratio, is the ratio in which ΔGb in the reaction system between the surface of the wafer 200 and the raw material gas becomes negative, and is the ratio in which an exothermic reaction occurs.

[0101] In the embodiments described above, the case in which a film containing Si is formed as a film containing a predetermined element was given as an example, but this disclosure is not limited thereto. The film containing a predetermined element may be a film containing a metallic element such as a titanium film (Ti film), titanium nitride film (TiN film), titanium oxide film (TiO film), tungsten film (W film), tungsten nitride film (WN film), tungsten oxide film (WO film), hafnium nitride film (HfN film), hafnium oxide film (HfO film), zirconium nitride film (ZrN film), zirconium oxide film (ZrO film), tantalum nitride film (TaN film), tantalum oxide film (TaO film), molybdenum film (Mo film), molybdenum nitride film (MoN film), molybdenum oxide film (MoO film), aluminum film (Al film), aluminum nitride film (AlN film), aluminum oxide film (AlO film), ruthenium film (Ru film), or cobalt film (Co film). In these cases as well, the same effects as those described above can be obtained.

[0102] The above-described embodiments illustrate an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at once. This disclosure is not limited to the above embodiments and can be suitably applied, for example, to forming a film using a single-wafer substrate processing apparatus that processes one or several substrates at once. Furthermore, the above-described embodiments illustrate an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace. This disclosure is not limited to the above embodiments and can be suitably applied to forming a film using a substrate processing apparatus having a cold-wall type processing furnace.

[0103] Even when using these substrate processing devices, each process can be carried out using the same processing procedures and conditions as described above, and the same effects as described above can be obtained.

[0104] The above embodiments can be used in combination as appropriate. The processing procedure and processing conditions in this case can be the same as, for example, the processing procedure and processing conditions in the above embodiments. [Explanation of Symbols]

[0105] 200 wafers (substrates)

Claims

1. (a) A step of supplying a first reactant that reacts with the surface of the substrate to the substrate at a first partial pressure, (b) After (a), the process is to evacuate the processing space of the substrate so that the partial pressure of the reaction product produced by the reaction between the surface of the substrate and the first reactant, which is present in the processing space of the substrate, becomes the second partial pressure. The process includes a step of forming a film on the substrate by performing a predetermined number of cycles including the following: (a) and (b) are performed such that the ratio of the second partial pressure to the first partial pressure is less than or equal to a predetermined partial pressure ratio. Substrate processing method.

2. The substrate processing method according to claim 1, wherein the predetermined partial pressure ratio is the ratio at which an exothermic reaction occurs in (b).

3. The predetermined partial pressure ratio is a ratio in which the formation free energy ΔG, which is the difference obtained by subtracting the magnitude of the energy level of the reaction system before the reaction between the surface of the substrate and the first reactant from the magnitude of the energy level of the reaction system after the reaction between the surface of the substrate and the first reactant, becomes negative. The substrate processing method according to claim 1.

4. The substrate processing method according to claim 1, wherein the predetermined partial pressure ratio is set according to the combination of the first reactant and the reaction product.

5. (b) The processing space is evacuated such that the partial pressure of the second reaction product, which is different from the reaction product and is produced by the reaction between the surface of the substrate and the first reactant, present in the processing space, becomes the third partial pressure. (a) and (b) are performed such that the first partial pressure and the third partial pressure are such that the ratio of the third partial pressure to the first partial pressure is less than or equal to a second predetermined partial pressure ratio. The substrate processing method according to claim 1.

6. The first reactant contains a gas containing hydrogen, The reaction product is a hydrogen-containing compound different from the first reactant. The substrate processing method according to claim 1.

7. (c) The process further includes the step of supplying a second reactant containing a halogen element to the substrate before (a), (a) In this case, a hydrogen-containing gas is supplied to the substrate as the first reactant. The reaction product is a compound of the halogen element and hydrogen or hydrogen gas. The substrate processing method according to claim 1.

8. The substrate processing method according to claim 7, wherein the first reactant contains hydrogen nitride gas.

9. The reaction product is a compound of the halogen element and hydrogen. The predetermined partial pressure ratio is 10 －５ The following is: The substrate processing method according to claim 8.

10. The reaction product is hydrogen gas. The predetermined partial pressure ratio is 10 －４ The following is: The substrate processing method according to claim 8.

11. The second reactant further comprises a predetermined element which is a metallic element or a metalloid element. The aforementioned film is a film containing the predetermined element. The substrate processing method according to claim 7.

12. (b) The substrate processing method according to claim 1, wherein an inert gas is supplied into the processing space of the substrate to reduce the partial pressure of the reaction product present in the processing space to the second partial pressure.

13. The substrate processing method according to claim 1, wherein in (b), the processing space is evacuated such that the ratio of the pressure in the processing space in (b) to the first partial pressure is less than or equal to the predetermined partial pressure ratio.

14. (b) The substrate processing method according to claim 1, wherein the partial pressure of the reaction product in the processing space is maintained to the second partial pressure for a predetermined period of time.

15. The substrate processing method according to claim 14, wherein the predetermined period is longer than the period after (a) until the partial pressure of the reaction product in the processing space reaches the second partial pressure.

16. (d) The process further includes a step of evacuating the processing space while stopping the supply of the second reactant between (c) and (a), The execution time of (b) is longer than the execution time of (d). The substrate processing method according to claim 7.

17. (a) is, (a-1) A step of filling the storage section with the first reactant and increasing the partial pressure of the first reactant in the storage section, (a-2) The process includes the step of supplying the first reactant, which has been filled in the storage section, to the substrate after (a-1), The substrate processing method according to claim 1.

18. (a) A step of supplying a first reactant that reacts with the surface of the substrate to the substrate at a first partial pressure, (b) After (a), the process is to evacuate the processing space of the substrate so that the partial pressure of the reaction product produced by the reaction between the surface of the substrate and the first reactant, which is present in the processing space of the substrate, becomes the second partial pressure. The process includes a step of forming a film on the substrate by performing a predetermined number of cycles including the following: (a) and (b) are performed such that the ratio of the second partial pressure to the first partial pressure is less than or equal to a predetermined partial pressure ratio. A method for manufacturing a semiconductor device.

19. (a) A procedure for supplying a first reactant that reacts with the surface of the substrate to the substrate at a first partial pressure, (b) After (a), the procedure of exhausting the processing space of the substrate so that the partial pressure of the reaction product produced by the reaction between the surface of the substrate and the first reactant present in the processing space of the substrate becomes the second partial pressure, A film is formed on the substrate by performing a predetermined number of cycles including the following: (a) and (b) are procedures performed such that the ratio of the second partial pressure to the first partial pressure is less than or equal to a predetermined partial pressure ratio, A program that causes a circuit board processing device to execute commands via a computer.

20. A first reactant supply system that supplies a first reactant that reacts with the surface of the substrate to the substrate, An exhaust system for exhausting the processing space of the aforementioned substrate, (a) A process of supplying the first reactant to the substrate at a first partial pressure, (b) After (a), the process of exhausting the processing space is performed such that the partial pressure of the reaction product produced by the reaction between the surface of the substrate and the first reactant present in the processing space becomes the second partial pressure. A film is formed on the substrate by performing a predetermined number of cycles including the following: (a) and (b) respectively include a control unit configured to control the first reactant supply system and the exhaust system so as to perform a process to make the first partial pressure and the second partial pressure such that the ratio of the second partial pressure to the first partial pressure is less than or equal to a predetermined partial pressure ratio, A substrate processing apparatus having

Images