Method for manufacturing semiconductor device, substrate processing method, substrate processing apparatus, and recording medium

Abstract

The present invention relates to a method for manufacturing a semiconductor device, a substrate processing method, a substrate processing apparatus, and a recording medium, which improve the characteristics of an oxide film formed on a substrate. An operation of forming a first oxide film containing an atom X is alternately performed, and the following operations are not performed simultaneously: an operation of forming a first layer containing a component in which a first functional group is bonded to the atom X, and an operation of oxidizing the first layer to form a second layer containing the atom X and oxygen; and an operation of forming a second oxide film containing the atom X is alternately performed, and the following operations are not performed simultaneously: an operation of forming a third layer containing a component in which the first functional group is bonded to the atom X, and an operation of forming a fourth layer containing the atom X and oxygen by oxidizing the third layer under processing conditions where the oxidizing power is higher than the oxidizing power when the first layer is oxidized.

Description

Technical Field

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

[0002] As one of the manufacturing processes of a semiconductor device, there is a case where the following substrate processing process is performed: The process of supplying a raw material to the substrate and the process of supplying an oxidant to the substrate are alternately repeated, thereby forming an oxide film on the substrate (for example, see Patent Documents 1 and 2).

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2008-135633

[0006] Patent Document 2: Japanese Patent Application Laid-Open No. 2010-153776 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] An object of the present invention is to improve the characteristics of an oxide film formed on a substrate.

[0009] Means for Solving the Problems

[0010] According to one aspect of the present invention, there is provided a technique having a step of alternately performing the following (a) and (b) a predetermined number of times to form an oxide film in which a first oxide film and a second oxide film are alternately laminated on a substrate:

[0011] (a) By performing a cycle of non-simultaneously performing the following (a1) and (a2) n 1 times (n 1 is an integer of 1 or more), a step of forming the first oxide film containing atom X is performed: (a1) A raw material having a partial structure in which a first functional group and a second functional group are directly bonded to atom X and the bond energy between the first functional group and atom X is higher than the bond energy between the second functional group and atom X is supplied to the substrate, and a step of forming a first layer containing a component in which the first functional group is bonded to atom X is performed; and (a2) A first oxidant is supplied to the substrate to oxidize the first layer, and a step of forming a second layer containing atom X and oxygen is performed; and

[0012] (b) By performing a cycle of non-simultaneously performing the following (b1) and (b2) n 2 times (n 2A step of forming the second oxide film containing the atom X (wherein m is an integer of 1 or more): (b1) a step of supplying the raw material to the substrate to form a third layer containing a component in which the first functional group is bonded to the atom X; and (b2) a step of supplying a second oxidant to the substrate under treatment conditions where the oxidizing power is higher than the oxidizing power when oxidizing the first layer in (a2), and oxidizing the third layer to form a fourth layer containing the atom X and oxygen.

[0013] Advantages of the Invention

[0014] According to the present invention, a technique capable of improving the characteristics of an oxide film formed on a substrate can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 FIG. 12 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferably used in one embodiment of the present invention, and is a diagram showing a part of the processing furnace 202 in a longitudinal sectional view.

[0016] Figure 2 FIG. 13 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferably used in one embodiment of the present invention, and is a diagram showing a part of the processing furnace 202 in Figure 1 a sectional view taken along line A-A of FIG. 13.

[0017] Figure 3 FIG. 14 is a schematic configuration diagram of a controller of a substrate processing apparatus preferably used in one embodiment of the present invention, and is a diagram showing a control system of the controller 121 in a block diagram.

[0018] Figure 4 FIG. 15 is a flowchart showing the gas supply sequence when forming the first oxide film in one embodiment of the present invention.

[0019] Figure 5 FIG. 16 is a flowchart showing the gas supply sequence when forming the second oxide film in one embodiment of the present invention.

[0020] Figure 6 FIG. 17 is a partially enlarged sectional view of the surface of a wafer 200 on which a laminated oxide film formed by alternately laminating a first oxide film and a second oxide film is formed in one embodiment of the present invention.

[0021] Figure 7 FIG. 18 is a partially enlarged sectional view of the surface of a wafer 200 on which a laminated oxide film formed by alternately laminating a first oxide film and a second oxide film is formed in a modified example of one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] <One Embodiment of the Present Invention>

[0023] Hereinafter, mainly using Figures 1 to 6A mode of the present invention will be described. It should be noted that the attached drawings used in the following description are all schematic drawings, and the dimensional relationships of the respective elements on the attached drawings, the ratios of the respective elements, etc. are not necessarily consistent with the actual situation. In addition, among multiple attached drawings, the dimensional relationships of the respective elements, the ratios of the respective elements, etc. are not necessarily consistent either.

[0024] (1) Configuration of the substrate processing apparatus

[0025] As Figure 1 shown, the processing furnace 202 has a heater 207 as a heating mechanism (temperature adjustment unit). The heater 207 has a cylindrical shape and is vertically installed by being supported on a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) a gas using heat.

[0026] 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 (SiO 2 ) or silicon carbide (SiC), and is formed in a cylindrical shape with a closed upper end and an open lower end. Below the reaction tube 203, a manifold 209 is arranged concentrically with the reaction tube 203. The manifold 209 is made of a metal material such as stainless steel (SUS), and is formed in a cylindrical shape with open upper and lower ends. The upper end portion of the manifold 209 is configured to engage with the lower end portion of the reaction tube 203 and support the reaction tube 203. An O-ring 220a as a sealing member is provided between the manifold 209 and the reaction tube 203. The reaction tube 203 is vertically installed in the same manner as the heater 207. The processing container (reaction container) is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed in the cylindrical hollow portion of the processing container. The processing chamber 201 is configured to be able to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed inside the processing chamber 201.

[0027] Inside the processing chamber 201, nozzles 249a and 249b as a first supply portion and a second supply portion are respectively provided so as to penetrate the side wall of the manifold 209. The nozzles 249a and 249b are also respectively referred to as the first nozzle and the second nozzle. The nozzles 249a and 249b are respectively made of a non-metal material such as quartz or SiC as a heat-resistant material.

[0028] Gas supply pipes 232a and 232b as a first pipe and a second pipe are respectively connected to the nozzles 249a and 249b. The nozzles 249a and 249b are adjacently arranged.

[0029] On the gas supply pipes 232a and 232b, mass flow controllers (MFCs) 241a and 241b serving as flow controllers (flow control units) and valves 243a and 243b serving as on-off valves are respectively provided in order from the upstream side of the gas flow. On the downstream side of the gas supply pipe 232a compared to the valve 243a, gas supply pipes 232c and 232d are connected. On the gas supply pipes 232c and 232d, MFCs 241c and 241d, valves 243c and 243d are respectively provided in order from the upstream side of the gas flow. On the downstream side of the gas supply pipe 232b compared to the valve 243b, a gas supply pipe 232e is connected. On the gas supply pipe 232e, an MFC 241e and a valve 243e are provided in order from the upstream side of the gas flow. The gas supply pipes 232a to 232e are made of a metal material such as SUS, for example.

[0030] As Figure 2 shown, the nozzles 249a and 249b are arranged in a space that is circular when viewed from above between the inner wall of the reaction tube 203 and the wafer 200, and are provided on the inner wall of the reaction tube 203 in a manner that stands upright upward along the arrangement direction toward the wafer 200 from the lower part to the upper part. That is, the nozzles 249a and 249b are respectively provided along the wafer arrangement area in an area that is horizontally surrounded by the side of the wafer arrangement area where the wafers 200 are arranged. On the side surfaces of the nozzles 249a and 249b, gas supply holes 250a and 250b for supplying gas are respectively provided. When viewed from above, the gas supply holes 250a and 250b are respectively opened toward the center of the wafer 200, so that gas can be supplied to the wafer 200. A plurality of gas supply holes 250a and 250b are provided in the range from the lower part to the upper part of the reaction tube 203.

[0031] A raw material (raw material gas) is supplied into the processing chamber 201 from the gas supply pipe 232a via the MFC 241a, the valve 243a, and the nozzle 249a. The raw material gas refers to a raw material in a gaseous state. For example, it is a gas obtained by vaporizing a raw material that is in a liquid state under normal temperature and pressure, a raw material that is in a gaseous state under normal temperature and pressure, and so on. In this specification, for convenience, there are also cases where the raw material gas is simply referred to as the raw material.

[0032] As an oxidant (oxidizing gas), an oxygen (O)-containing gas is supplied into the processing chamber 201 from the gas supply pipe 232b via the MFC 241b, the valve 243b, and the nozzle 249b. The O-containing gas functions as an oxidizing gas, that is, an O source.

[0033] As a reducing agent (reducing gas), a hydrogen (H)-containing gas is supplied into the processing chamber 201 from the gas supply pipe 232c via the MFC 241c, the valve 243c, the gas supply pipe 232a, and the nozzle 249a. The H-containing gas does not have an oxidizing effect on its own, but in the substrate processing step described later, by reacting with an O-containing gas under specific conditions, oxidation species such as atomic oxygen (O) are generated, and it functions in a way to improve the efficiency of the oxidation treatment. Therefore, the H-containing gas can be considered to be included in the oxidant.

[0034] An inert gas is supplied into the processing chamber 201 from the gas supply pipes 232d and 232e via the MFCs 241d and 241e, the valves 243d and 243e, the gas supply pipes 232a and 232b, and the nozzles 249a and 249b. The inert gas functions as a purge gas, a carrier gas, a dilution gas, etc.

[0035] The raw material supply system, that is, the raw material gas supply system, is mainly composed of the gas supply pipe 232a, the MFC 241a, and the valve 243a. The oxidant supply system (the first oxidant supply system, the second oxidant supply system), that is, the oxidation gas supply system (O-containing gas supply system), is mainly composed of the gas supply pipe 232b, the MFC 241b, and the valve 243b. The reducing agent supply system, that is, the reducing gas supply system (H-containing gas supply system), is composed of the gas supply pipe 232c, the MFC 241c, and the valve 243c. The gas supply pipe 232c, the MFC 241c, and the valve 243c can also be considered to be included in the oxidant supply system. The inert gas supply system is mainly composed of the gas supply pipes 232d and 232e, the MFCs 241d and 241e, and the valves 243d and 243e.

[0036] It should be noted that the raw material and the oxidant, either one or both, are also called film-forming gases, and the raw material supply system and the oxidant supply system, either one or both, are also called film-forming gas supply systems.

[0037] Any one or all of the above supply systems may also be configured as an integrated supply system 248 formed by integrating valves 243a to 243e, MFCs 241a to 241e, etc. The integrated supply system 248 is configured to be connected to each gas supply pipe 232a to 232e, and the supply operation of various gases into the gas supply pipes 232a to 232e is controlled by a controller 121 described later, that is, the opening and closing operations of the valves 243a to 243e, the flow rate adjustment operations using the MFCs 241a to 241e, etc. The integrated supply system 248 is configured as an integrated unit in an integrated or split form, and is configured to be attachable and detachable with respect to the gas supply pipes 232a to 232e, etc. in units of integrated units, and maintenance, replacement, addition, etc. of the integrated supply system 248 can be performed in units of integrated units.

[0038] Below the side wall of the reaction tube 203, an exhaust port 231a for exhausting the atmosphere in the processing chamber 201 is provided. The exhaust port 231a may also be provided from the lower part to the upper part of the side wall of the reaction tube 203, that is, along the wafer arrangement area. An exhaust pipe 231 is connected to the exhaust port 231a. The exhaust pipe 231 is made of a metal material such as SUS, for example. A vacuum pump 246 as a vacuum exhaust device is connected to the exhaust pipe 231 via a pressure sensor 245 as a pressure detector (pressure detection unit) for detecting the pressure in the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 as a pressure regulator (pressure adjustment unit). The APC valve 244 is configured to be able to perform vacuum exhaust and stop of vacuum exhaust in the processing chamber 201 by opening and closing the valve in a state where the vacuum pump 246 is operating, and to be able to adjust the pressure in the processing chamber 201 by adjusting the valve opening based on the pressure information detected by the pressure sensor 245 in a state where the vacuum pump 246 is operating. The exhaust system is mainly composed of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may also be considered to be included in the exhaust system.

[0039] Below the manifold 209, a sealing cover 219, which serves as a furnace port cover body, is provided to airtightly seal the lower end opening of the manifold 209. The sealing cover 219 is made of a metal material such as SUS, for example, and is formed in a disc shape. On the upper surface of the sealing cover 219, an O-ring 220b, which serves as a sealing member, is provided to abut against the lower end of the manifold 209. Below the sealing cover 219, a rotation mechanism 267 is provided to rotate a susceptor 217 described later. The rotation shaft 255 of the rotation mechanism 267 (made of a metal material such as SUS, for example) is connected to the susceptor 217 in a manner that penetrates the sealing cover 219. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the susceptor 217. The sealing cover 219 is configured to move up and down in the vertical direction by a susceptor elevator 115, which serves as a lifting mechanism, provided outside the reaction tube 203. The susceptor elevator 115 is configured as a transfer system (transfer mechanism), which transfers (carries in and out) the wafer 200 into and out of the processing chamber 201 by moving the sealing cover 219 up and down.

[0040] Below the manifold 209, a gate plate 219s, which serves as a furnace port cover body, is provided to airtightly seal the lower end opening of the manifold 209 in a state where the sealing cover 219 is lowered and the susceptor 217 is carried out of the processing chamber 201. The gate plate 219s is made of a metal material such as SUS, for example, and is formed in a disc shape. On the upper surface of the gate plate 219s, an O-ring 220c, which serves as a sealing member, is provided to abut against the lower end of the manifold 209. The opening and closing operation (lifting operation, rotation operation, etc.) of the gate plate 219s is controlled by a gate plate opening and closing mechanism 115s.

[0041] The susceptor 217, which serves as a substrate support member, is configured to support a plurality of wafers 200, for example, 25 to 200 wafers, in a horizontally aligned state with their centers aligned and arranged in multiple layers in the vertical direction, that is, arranged at intervals. The susceptor 217 is made of a heat-resistant material such as quartz or SiC, for example. Heat insulation plates 218, made of a heat-resistant material such as quartz or SiC, for example, are supported in multiple layers at the lower part of the susceptor 217.

[0042] Inside the reaction tube 203, a temperature sensor 263, which serves as a temperature detector, is provided. By adjusting the energization state of the heater 207 based on the temperature information detected by using the temperature sensor 263, the temperature inside the processing chamber 201 becomes a desired temperature distribution. The temperature sensor 263 is provided along the inner wall of the reaction tube 203.

[0043] As Figure 3As shown in the figure, the controller 121, which serves as the control unit (control mechanism), is configured by a computer including a CPU (Central Processing Unit), a RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, the storage device 121c, and the I / O port 121d are configured to be able to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122 configured by, for example, a touch panel is connected to the controller 121.

[0044] The storage device 121c is constituted by, for example, a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), etc. In the storage device 121c, a control program for controlling the operation of the substrate processing apparatus, a process recipe including steps, conditions, etc. of the substrate processing described later, etc. are stored in a readable manner. The process recipe is a combination of the respective steps in the substrate processing described later in such a way that the controller 121 can execute it and obtain a predetermined result, and functions as a program. Hereinafter, the control program, the process recipe, etc. will also be simply referred to as a program. In addition, the process recipe will also be simply referred to as a recipe. In this specification, when the term "program" is used, there are cases where it includes only the recipe, cases where it includes only the control program, or cases where it includes both the recipe and the control program. The RAM 121b is configured as a memory area (working area) that temporarily holds programs, data, etc. read by the CPU 121a.

[0045] The I / O port 121d is connected to the above-mentioned MFCs 241a to 241e, valves 243a to 243e, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotation mechanism 267, susceptor elevator 115, gate opening / closing mechanism 115s, etc.

[0046] The CPU 121a is configured to be able to read a control program from the storage device 121c and execute it, and read a process from the storage device 121c corresponding to the input of an operation command from the input / output device 122, etc. The CPU 121a is configured to be able to control various gas flow adjustment operations performed by the MFCs 241a to 241e, opening and closing operations of the valves 243a to 243e, opening and closing operations of the APC valve 244, and pressure adjustment operations performed by the APC valve 244 based on the pressure sensor 245, starting and stopping of the vacuum pump 246, temperature adjustment operations of the heater 207 based on the temperature sensor 263, rotation and rotation speed adjustment operations of the susceptor 217 performed by the rotation mechanism 267, lifting operations of the susceptor 217 performed by the susceptor lifter 115, opening and closing operations of the gate 219s performed by the gate opening and closing mechanism 115s, etc. according to the content of the read process.

[0047] The controller 121 can be configured by installing the above program saved in the external storage device 123 on a computer. The external storage device 123 includes, for example, magnetic disks such as HDDs, optical discs such as CDs, magneto-optical discs such as MOs, USB memories, semiconductor memories such as SSDs, etc. The storage device 121c and the external storage device 123 are constituted by recording media readable by a computer. Hereinafter, the above components will also be simply collectively referred to as recording media. In the case of using the term recording medium in this specification, there are cases where only the storage device 121c is included, cases where only the external storage device 123 is included, or cases where both the storage device 121c and the external storage device 123 are included. It should be noted that the program can also be provided to the computer without using the external storage device 123 but using a communication mechanism such as the Internet or a dedicated line.

[0048] (2) Substrate processing step

[0049] As one step of the manufacturing process of semiconductor devices, for the sequence example of processing the wafer 200 as a substrate using the above substrate processing apparatus, that is, the film formation sequence example of forming an oxide film on the wafer 200, mainly Figures 4 to 6 will be described. In the following description, the operations of each part constituting the substrate processing apparatus are controlled by the controller 121.

[0050] In the film formation sequence in this mode, the following step A and step B are alternately performed a specified number of times to form an oxide film (laminated oxide film) in which the first oxide film and the second oxide film are alternately laminated on the wafer 200:

[0051] Step A, by performing the cycle of non-simultaneously performing the following step a1 and step a2 for n 1 times (n 1forming a first oxide film containing atom X by performing the following steps a1, a2, and repeating the cycle of non-simultaneously performing the following steps b1 and b2 n times (n is an integer of 1 or more): Step a1 of supplying a raw material gas having a partial structure in which a first functional group and a second functional group are directly bonded to atom X and the bond energy between the first functional group and atom X is higher than the bond energy between the second functional group and atom X to wafer 200 to form a first layer containing a component in which the first functional group is bonded to atom X; Step a2 of supplying a first oxidant to wafer 200 to oxidize the first layer to form a second layer containing atom X and O; and

[0052] forming a second oxide film containing atom X by performing the following steps B: Step b1 of supplying the above raw material gas to wafer 200 to form a third layer containing a component in which the first functional group is bonded to atom X; and Step b2 of supplying a second oxidant to wafer 200 under processing conditions where the oxidizing power is higher than that when oxidizing the first layer in step a2 to oxidize the third layer to form a fourth layer containing atom X and O. The cycle of non-simultaneously performing the following steps b1 and b2 is repeated n times (n is an integer of 1 or more). 2 times (n 2 is an integer of 1 or more).

[0053] Hereinafter, the case where atom X contains, for example, silicon (Si) will be described. In this case, as the first oxidant, for example, an O-containing gas can be used. As the second oxidant, for example, an O-containing gas and an H-containing gas can be used. In this case, the following occurs: as the first layer, a layer containing a component in which the first functional group is bonded to Si is formed, as the second layer, a layer containing Si and O is formed, as the third layer, a layer containing a component in which the first functional group is bonded to Si is formed, and as the fourth layer, a layer containing Si and O is formed. In addition, in this case, the following occurs: as the first oxide film, a film containing Si and O, that is, a first silicon oxide film (first SiO film) is formed, and as the second oxide film, a film containing Si and O, that is, a second silicon oxide film (second SiO film) is formed. Finally, a SiO film (stacked SiO film) in which the first SiO film and the second SiO film are alternately stacked is formed on wafer 200. Hereinafter, this example will be described in detail.

[0054] It should be noted that Figure 4 shows the film formation order (gas supply order) when forming the first SiO film, Figure 5 and shows the film formation order (gas supply order) when forming the second SiO film. Figure 4 In, a1 shows step a1 and a2 shows step a2. Figure 5 In, b1 shows step b1 and b2 shows step b2.

[0055] In the present specification, for convenience, the above film formation order is shown as follows. The same expression is used in the following modification examples and descriptions of other methods.

[0056] (Raw material gas → O-containing gas) × n 1 → (Raw material gas → O-containing gas + H-containing gas) × n 2 → ···

[0057] It should be noted that when a group that performs step A and step B non-simultaneously is performed a specified number of times (n 3 times, n 3 is an integer of 1 or more), for convenience, the above film formation sequence can be shown as follows. It should be noted that this example shows an example where step A is performed first and step B is performed last.

[0058] [(Raw material gas → O-containing gas) × n 1 → (Raw material gas → O-containing gas + H-containing gas) × n 2 × n 3

[0059] In addition, when a group that performs step A and step B non-simultaneously is performed a specified number of times (n 3 times, n 3 is an integer of 1 or more) and then step A is performed, for convenience, the above film formation sequence can also be shown as follows. It should be noted that this example shows an example where step A is performed first and last.

[0060] [(Raw material gas → O-containing gas) × n 1 → (Raw material gas → O-containing gas + H-containing gas) × n 2 × n 3 → (Raw material gas → O-containing gas) × n 1

[0061] In addition, when a group that performs step B and step A non-simultaneously is performed a specified number of times (n 3 times, n 3 is an integer of 1 or more), for convenience, the above film formation sequence can also be shown as follows. It should be noted that this example shows an example where step B is performed first and step A is performed last.

[0062] [(Raw material gas → O-containing gas + H-containing gas) × n 2 → (Raw material gas → O-containing gas) × n 1 × n 3

[0063] In addition, when a group that performs step B and step A non-simultaneously is performed a specified number of times (n 3 times, n 3 is an integer of 1 or more) and then step A is performed, for convenience, the above film formation sequence can also be shown as follows. It should be noted that this example shows an example where step B is performed first and last.

[0064] [(Raw material gas → O-containing gas + H-containing gas) × n 2 → (Raw material gas → O-containing gas) × n 1 × n 3 → (Raw material gas → O-containing gas + H-containing gas) × n 2

[0065] In these cases, when step A is carried out multiple times, the n values for each of the multiple executions of step A can be the same or different. When step B is carried out multiple times, the n values for each of the multiple executions of step B can be the same or different. 1 When the term "wafer" is used in this specification, there are cases where it represents the wafer itself, and cases where it represents a laminate of the wafer and a specified layer or film formed on its surface. When the term "surface of the wafer" is used in this specification, there are cases where it represents the surface of the wafer itself, and cases where it represents the surface of a specified layer or the like formed on the wafer. When it is described in this specification that "a specified layer is formed on the wafer", there are cases where it represents directly forming a specified layer on the surface of the wafer itself, and cases where it represents forming a specified layer on a layer or the like formed on the wafer. The cases where the term "substrate" is used in this specification have the same meaning as the cases where the term "wafer" is used. 2

[0066] In this specification, when the term "wafer" is used, there are cases where it represents the wafer itself, and cases where it represents a laminate of the wafer and a specified layer or film formed on its surface. When the term "surface of the wafer" is used in this specification, there are cases where it represents the surface of the wafer itself, and cases where it represents the surface of a specified layer or the like formed on the wafer. When it is described in this specification that "a specified layer is formed on the wafer", there are cases where it represents directly forming a specified layer on the surface of the wafer itself, and cases where it represents forming a specified layer on a layer or the like formed on the wafer. The cases where the term "substrate" is used in this specification have the same meaning as the cases where the term "wafer" is used.

[0067] (Wafer filling, boat loading)

[0068] After loading multiple wafers 200 into the boat 217 (wafer filling), the shutter 219s is moved by the shutter opening / closing mechanism 115s, and the lower end opening of the manifold 209 is opened (shutter opening). After that, as Figure 1 shown, the boat 217 supporting multiple wafers 200 is lifted by the boat elevator 115 and carried into the processing chamber 201 (boat loading). In this state, the seal cover 219 is in a state where the lower end of the manifold 209 is sealed by the O-ring 220b.

[0069] (Pressure regulation and temperature regulation)

[0070] After the wafer boat is loaded, vacuum evacuation (pressure reduction evacuation) is performed by the vacuum pump 246 so that the pressure (vacuum degree) in the processing chamber 201, that is, the space where the wafer 200 is located, becomes a desired pressure. At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and feedback control (pressure adjustment) is performed on the APC valve 244 based on the measured pressure information. In addition, heating is performed by the heater 207 so that the wafer 200 in the processing chamber 201 becomes a desired processing temperature. At this time, feedback control is performed on the energization state of the heater 207 based on the temperature information detected by the temperature sensor 263 so that a desired temperature distribution (temperature adjustment) is achieved in the processing chamber 201. In addition, the wafer 200 is rotated by the rotation mechanism 267. Exhaust in the processing chamber 201, heating of the wafer 200, and rotation are all continuously performed at least until the processing of the wafer 200 is completed.

[0071] The surface of the wafer 200 becomes a state capped with hydroxyl groups (that is, hydroxy group, -OH). That is, an OH cap is formed on the surface of the wafer 200. The OH caps present on the surface of the wafer 200 function as adsorption sites for molecules and atoms of the source gas used in this method.

[0072] (Stacked oxide film formation)

[0073] Then, step A of forming the first SiO film and step B of forming the second SiO film are alternately performed a specified number of times in a specified order.

[0074] [Step A]

[0075] In step A, the following steps a1 and a2 are sequentially performed.

[0076] [Step a1]

[0077] In this step, a source gas is supplied to the wafer 200 in the processing chamber 201.

[0078] Specifically, the valve 243a is opened to allow the source gas to flow into the gas supply pipe 232a. The source gas is flow-regulated by the MFC241a, supplied into the processing chamber 201 via the nozzle 249a, and exhausted from the exhaust port 231a. At this time, the source gas is supplied to the wafer 200 (source gas supply). At this time, the valves 243d and 243e may also be opened to supply an inert gas into the processing chamber 201 via the nozzles 249a and 249b.

[0079] In this step, the source gas is supplied under the condition that the first functional group does not detach from Si of the atom X contained in the source gas while the second functional group detaches, and Si in a state where the second functional group has detached and the bonding with the first functional group is maintained adsorbs onto the surface of the wafer 200. As the source gas, when using a gas in which the first functional group is bonded to each of three of the four bonding sites of Si and the second functional group is bonded to the remaining one of the four bonding sites of Si, in this step, the source gas is supplied under the processing conditions where the first functional group is bonded to each of three of the bonding sites of Si and Si adsorbs onto the surface of the wafer 200. It should be noted that the bond energy E of the first functional group and Si O is higher than the bond energy E of the second functional group and Si A . That is, compared with the first functional group, the second functional group has a more reactive characteristic of being easily detached from Si.

[0080] By performing this step under such processing conditions, it is possible to cause the second functional group to detach without the first functional group detaching from the Si contained in the source gas. In addition, it is possible to cause Si in a state where the second functional group has detached and the bonding with the first functional group is maintained to adsorb onto the surface of the wafer 200 (chemical adsorption). As a result, for example, it is possible to cause Si to adsorb onto a part of the adsorption sites on the surface of the wafer 200 in a state where the first functional group is bonded to three of the four bonding sites of Si. In this way, it becomes possible to form a first layer containing a component in which the first functional group is bonded to Si on the outermost surface of the wafer 200. In addition, it is possible to form a state where the outermost surface of the first layer is capped with a chemically stable first functional group.

[0081] In addition, in this step, the source gas is supplied under the following conditions: the adsorption of Si in a state where the second functional group has detached and the bonding with the first functional group is maintained onto the surface of the wafer 200 is dominant compared to the adsorption of the second functional group detached from Si onto the surface of the wafer 200.

[0082] By performing this step under such processing conditions, the adsorption of the second functional group detached from Si contained in the source gas onto the surface of the wafer 200 can be suppressed, and the second functional group can be prevented from adsorbing onto the surface of the wafer 200. As a result, it is possible to suppress the second functional group detached from Si contained in the source gas from mixing into the first layer formed on the wafer 200, and the first layer can be made free of the second functional group. That is, the first layer formed on the wafer 200 can be made into a layer with a low content of the second functional group and few impurities (such as carbon (C), nitrogen (N), etc.) from the second functional group. In addition, it can be made into a state where the outermost surface of the first layer is capped with a chemically stable first functional group.

[0083] In addition, in this step, it is possible to utilize the first functional group bonded to Si adsorbed on the surface of the wafer 200, that is, by embedding (encapsulating) the bonding bond of Si adsorbed on the surface of the wafer 200 with the first functional group, thereby hindering the adsorption of at least any one of atoms or molecules to Si adsorbed on the surface of the wafer 200. In addition, in this step, by making the first functional group bonded to Si adsorbed on the surface of the wafer 200 function as a steric hindrance, it is possible to hinder the adsorption of at least any one of atoms or molecules around Si adsorbed on the surface of the wafer 200 to the adsorption site (OH-terminated) on the surface of the wafer 200. Thereby, the in-plane thickness uniformity and step coverage of the first layer formed on the wafer 200 can be improved.

[0084] In addition, in this step, by using the first functional group bonded to Si adsorbed on the surface of the wafer 200, it is possible to maintain the adsorption site (OH-terminated) on the surface of the wafer 200 around it. In addition, in this step, Si can be adsorbed on the surface of the wafer 200 discontinuously. That is, in this step, Si can be adsorbed on the surface of the wafer 200 in a thickness less than one atomic layer. Thereby, the in-plane thickness uniformity and step coverage of the first layer formed on the wafer 200 can be improved.

[0085] In this step, it is preferable to continuously supply the source gas until the adsorption reaction (chemisorption reaction) of Si on the surface of the wafer 200 reaches saturation. Even if the source gas is continuously supplied in this way, Si can be adsorbed on the surface of the wafer 200 discontinuously because the first functional group bonded to Si functions as a steric hindrance. Thereby, the in-plane thickness uniformity and step coverage of the first layer formed on the wafer 200 can be improved.

[0086] It should be noted that in the state where the adsorption reaction of Si on the surface of the wafer 200 reaches saturation, the first layer composed of Si adsorbed on the surface of the wafer 200 has a thickness less than one atomic layer. That is, in the state where the adsorption reaction of Si on the surface of the wafer 200 reaches saturation, the first layer composed of Si adsorbed on the surface of the wafer 200 becomes a discontinuous layer. Thereby, the in-plane thickness uniformity and step coverage of the first layer formed on the wafer 200 can be improved.

[0087] In addition, in the state where the adsorption reaction of Si on the surface of the wafer 200 reaches saturation, a part of the surface of the wafer 200 is in a state where the adsorption site (OH-terminated) is not consumed but maintained. Thereby, the in-plane thickness uniformity and step coverage of the first layer formed on the wafer 200 can be improved.

[0088] In addition, in a state where the adsorption reaction of Si on the surface of the wafer 200 is saturated, the surface of the wafer 200 becomes a state covered with the first functional group bonded to Si. Thereby, the in-plane thickness uniformity and step coverage of the first layer formed on the wafer 200 can be improved.

[0089] After forming the first layer, the valve 243a is closed to stop supplying the source gas into the processing chamber 201. Then, the inside of the processing chamber 201 is evacuated, and the gas remaining in the processing chamber 201, etc. is exhausted from the processing chamber 201 (purge). At this time, the valves 243d and 243e are opened to supply an inert gas into the processing chamber 201. The inert gas functions as a purge gas.

[0090] As the source gas, it is preferable to use the following substances: having a partial structure in which a first functional group and a second functional group are directly bonded to Si as atom X, and the bond energy E of the first functional group with Si as atom X O is higher than the bond energy E of the second functional group with Si as atom X A . The first functional group may also include a third functional group.

[0091] The first functional group includes, for example, an alkoxy group. The so-called alkoxy group has a structure in which an alkyl group (R) as the third functional group is bonded to an oxygen (O) atom, and is a monovalent functional group represented by the structural formula -OR. In the alkoxy group (-OR), there are included methoxy (-OMe), ethoxy (-OEt), propoxy (-OPr), butoxy (-OBu), etc. The alkoxy group may be not only the above-mentioned linear alkoxy group but also branched alkoxy groups such as isopropoxy, isobutoxy, sec-butoxy, and tert-butoxy. In addition, as the alkyl group (-R) as the above-mentioned third functional group, there are included methyl (-Me), ethyl (-Et), propyl (-Pr), butyl (-Bu), etc. The alkyl group is not only the above-mentioned linear alkyl group but also branched alkyl groups such as isopropyl, isobutyl, sec-butyl, and tert-butyl.

[0092] The second functional group includes, for example, an amino group. The so-called amino group has a structure obtained by removing hydrogen (H) from any one of ammonia (NH 3 ), primary amine, and secondary amine, and is a monovalent functional group represented by any one of the structural formulas -NH 2 , -NHR, and -NRR'. R and R' shown in the structural formula are alkyl groups including methyl, ethyl, propyl, butyl, etc. R and R' are not only the above-mentioned linear alkyl groups but also branched alkyl groups such as isopropyl, isobutyl, sec-butyl, and tert-butyl. R and R' may be the same alkyl group or different alkyl groups. As the amino group, for example, dimethylamino (-N(CH 3 )) 2 ), diethylamino (-N(C 2 H5 ) 2 ) etc.

[0093] The bond energy E of alkoxy groups such as methoxy, ethoxy, propoxy, and butoxy with Si O is higher than the bond energy E of amino groups with Si. That is, compared with alkoxy groups, amino groups have the active characteristic of being easily detached from Si. A As raw material gases, for example, trimethoxy(dimethylamino)silane ([(CH

[0094] ) 3 ) 2 N]Si(OCH 3 ) 3 ), abbreviated as: TMDMAS) gas, triethoxy(diethylamino)silane ([(C 2 H 5 ) 2 N]Si(OC 2 H 5 ) 3 ), abbreviated as: TEDEAS) gas, triethoxy(dimethylamino)silane ([(CH 3 ) 2 N]Si(OC 2 H 5 ) 3 ), abbreviated as: TEDMAS) gas, trimethoxy(diethylamino)silane ([(C 2 H 5 ) 2 N]Si(OCH 3 ) 3 ), abbreviated as: TMDEAS) gas, etc. The Si contained in these raw materials has 4 bonding sites. On 3 of the 4 bonding sites of Si, alkoxy groups (methoxy, ethoxy) as the first functional group are bonded, and on the remaining 1 bonding site of the 4 bonding sites of Si, amino groups (dimethylamino, diethylamino) as the second functional group are bonded. The ratio of the number of amino groups to the number of alkoxy groups contained in these raw materials is 1:3. As raw material gases, one or more of these can be used.

[0095] In addition, the raw material gas is not limited to the above gases, as long as the bond energy E of the first functional group with Si O is higher than the bond energy E of the second functional group with Si NFor a high gas, the same structure can be suitably used, that is, various gases having a partial structure in which a first functional group and a second functional group are directly bonded to Si as atom X (central atom). That is, as the source gas, a gas having a partial structure in which a first functional group and a second functional group are directly bonded to Si as atom X (central atom) can be suitably used, and the first functional group includes an alkoxy group, and the second functional group includes at least any one of an amino group, an alkyl group, a halogenated group, a hydroxyl group, a hydrogen group, an aryl group, a vinyl group, and a nitro group. Here, the alkyl group includes a methyl group, an ethyl group, a propyl group, a butyl group, etc. In addition, the halogenated group includes a chlorine group, a fluorine group, a bromine group, an iodine group, etc. That is, the halogenated group includes halogen elements such as chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc.

[0096] As the inert gas, for example, nitrogen (N 2 ) gas, argon (Ar) gas, helium (He) gas, neon (Ne) gas, xenon (Xe) gas and other rare gases can be used. As the inert gas, one or more of these can be used. This is the same in each of the steps described later.

[0097] [Step a2]

[0098] After step a1 is completed, an O-containing gas is supplied as the first oxidant to the wafer 200 in the processing chamber 201, that is, the first layer formed on the wafer 200.

[0099] Specifically, the valve 243b is opened to allow the O-containing gas to flow into the gas supply pipe 232b. The O-containing gas is flow-regulated by the MFC241b, supplied into the processing chamber 201 via the nozzle 249b, and exhausted from the exhaust port 231a. At this time, the O-containing gas is supplied to the wafer 200 (O-containing gas supply). At this time, the valves 243d and 243e can also be opened to supply an inert gas into the processing chamber 201 via the nozzles 249a and 249b.

[0100] In this step, the O-containing gas is supplied under the processing conditions in which at least any one of the third functional group contained in the first functional group bonded to Si and the first functional group bonded to Si in the first layer is detached.

[0101] By performing this step under such processing conditions, at least any one of the third functional group (including its residue) contained in the first functional group bonded to Si and the first functional group (including its residue) bonded to Si contained in the first layer can be detached from the first layer. Moreover, at least a part of the first layer formed on the wafer 200 can be oxidized (modified) to form a layer containing Si and O, i.e., a silicon oxide layer (SiO layer), as the second layer. The second layer becomes a layer with a lower content of impurities derived from the third functional group, the first functional group, and their residues compared to the first layer, that is, a layer with a lower content of impurities such as C and H compared to the first layer. In addition, for the surface of the second layer, as a result of the oxidation treatment with an O-containing gas, it becomes a state terminated with OH, that is, a state in which adsorption sites are formed. It should be noted that impurities such as C and H detached from the first layer form a gaseous substance containing C, H, etc., which is discharged from the inside of the processing chamber 201.

[0102] After forming the second layer, the valve 243b is closed, and the supply of the O-containing gas into the processing chamber 201 is stopped. Then, through the same processing steps as the purge in step a1, the gas remaining in the processing chamber 201 is removed (purged) from the processing chamber 201.

[0103] As the first oxidant, i.e., the O-containing gas, for example, oxygen (O 2 ) gas, nitric oxide (NO) gas, nitrous oxide (N 2 O) gas, nitrogen dioxide (NO 2 ) gas, carbon monoxide (CO) gas, carbon dioxide (CO 2 ) gas, etc. can be used. As the first oxidant, one or more of these can be used.

[0104] [Implement a specified number of times]

[0105] By performing the cycles of the above steps a1 and a2 non-simultaneously, i.e., asynchronously, a specified number of times (n 1 times, n 1 is an integer of 1 or more), a first SiO film with a specified composition and a specified film thickness can be formed on the wafer 200. It is preferable to repeat the above cycles multiple times. That is, it is preferable that the thickness of the second layer formed by performing one cycle of the above is smaller than the desired film thickness, and the above cycles are repeated until the film thickness of the first SiO film formed by laminating the second layer becomes the desired film thickness. The thickness of the first SiO film can be set, for example, to be 0.1 nm or more and 5 nm or less, preferably in the range of 0.5 nm or more and 3 nm or less.

[0106] It should be noted that for the first SiO film, compared with the second SiO film described later, the in-plane film thickness uniformity and step coverage on the wafer surface are excellent. In addition, it has the characteristic of maintaining the substrate oxidation amount in a good state. The reason why the first SiO film has excellent in-plane film thickness uniformity and step coverage compared with the second SiO film is that in step a2, the first layer is oxidized under processing conditions where the oxidation power is weaker (lower) than that in step b2 described later. Specifically, because in step a2, only an O-containing gas is used as the first oxidant, that is, a gas that is less likely to be deactivated in a short time compared with the second oxidant used in step b2 described later is used. At this time, in step a2, the O-containing gas can react equally with the first layer whether at the peripheral part or the central part of the wafer 200. As a result, the first SiO film can be made into a film with excellent in-plane film thickness uniformity and step coverage. In addition, the reason why the substrate oxidation amount can be maintained in a good state when forming the first SiO film compared with when forming the second SiO film is that in step a2, the first layer is oxidized under processing conditions where the oxidation power is weaker than that in step b2 described later. Specifically, because in step a2, a gas with a weaker oxidation power than the second oxidant used in step b2 described later is used as the first oxidant. At this time, the oxidation of the substrate can be sufficiently suppressed, that is, the oxidation of the surface of the wafer 200 in contact with the first SiO film.

[0107] [Step B]

[0108] In step B, the following steps b1 and b2 are performed in sequence.

[0109] [Step b1]

[0110] The processing steps and processing conditions in this step are the same as those in step a1 described above.

[0111] That is, in this step, the raw material gas is supplied under the following conditions: the first functional group does not detach from Si as atom X contained in the raw material gas while the second functional group detaches, and Si in a state where the second functional group detaches and the bond with the first functional group is maintained adsorbs to the surface of the wafer 200. When a gas in which the first functional group is bonded to each of the three bonding bonds of the four bonding bonds possessed by Si and the second functional group is bonded to the remaining one of the four bonding bonds of Si is used as the raw material gas, in this step, the raw material gas is supplied under the processing conditions where Si is adsorbed to the surface of the wafer 200 in a state where the first functional group is bonded to each of the three bonding bonds of Si. By performing this step under such processing conditions, a third layer containing a component in which the first functional group is bonded to Si can be formed on the outermost surface of the wafer 200. In addition, a state where the outermost surface of the third layer is capped with a chemically stable first functional group can be formed.

[0112] In addition, in this step, the raw material gas is supplied under the following processing conditions: compared with the adsorption of the second functional group detached from Si to the surface of the wafer 200, the adsorption of Si in the state where the second functional group is detached and the bonding with the first functional group is maintained to the surface of the wafer 200 is dominant (advantageous). By performing this step under such processing conditions, the third layer can be made into a layer with a small content of the second functional group and few impurities (such as C, N, etc.) from the second functional group. In addition, a state can be formed in which the outermost surface of the third layer is capped with the chemically stable first functional group.

[0113] In addition, in this step, similar to step a1, it is possible to use the first functional group bonded to Si adsorbed on the surface of the wafer 200 to hinder the adsorption of at least one of atoms or molecules to Si adsorbed on the surface of the wafer 200. In addition, the adsorption of at least one of atoms or molecules to the adsorption site (OH-capped) on the surface of the wafer 200 around Si adsorbed on the surface of the wafer 200 can be hindered. Thereby, the in-plane thickness uniformity and step coverage of the third layer formed on the wafer 200 can be improved.

[0114] In addition, in this step, similar to step a1, it is possible to use the first functional group bonded to Si adsorbed on the surface of the wafer 200 to maintain the adsorption site (OH-capped) on the surface of the wafer 200 around it. In addition, in this step, Si can be discontinuously adsorbed on the surface of the wafer 200. That is, in this step, Si can be adsorbed on the surface of the wafer 200 in a thickness less than 1 atomic layer. Thereby, the in-plane thickness uniformity and step coverage of the third layer formed on the wafer 200 can be improved.

[0115] In addition, in this step, similar to step a1, it is preferable to continuously supply the raw material gas until the adsorption reaction (chemical adsorption reaction) of Si to the surface of the wafer 200 is saturated. Even if the raw material gas is continuously supplied in this way, Si can be discontinuously adsorbed on the surface of the wafer 200. Thereby, the in-plane thickness uniformity and step coverage of the third layer formed on the wafer 200 can be improved.

[0116] In addition, in the state where the adsorption reaction of Si to the surface of the wafer 200 is saturated, the third layer composed of Si adsorbed on the surface of the wafer 200 becomes a discontinuous layer with a thickness less than 1 atomic layer. Thereby, the in-plane thickness uniformity and step coverage of the third layer formed on the wafer 200 can be improved.

[0117] In addition, in a state where the adsorption reaction of Si to the surface of the wafer 200 is saturated, a part of the surface of the wafer 200 becomes a state where the adsorption sites (OH-terminated) are not consumed but retained. Thereby, the in-plane thickness uniformity and step coverage of the third layer formed on the wafer 200 can be improved.

[0118] In addition, in a state where the adsorption reaction of Si to the surface of the wafer 200 is saturated, the surface of the wafer 200 becomes a state covered with the first functional group bonded to Si. Thereby, the in-plane thickness uniformity and step coverage of the third layer formed on the wafer 200 can be improved.

[0119] After forming the third layer, the valve 243a is closed, and the supply of the source gas into the processing chamber 201 is stopped. Then, using the same processing steps as the purge in step a1, the gas and the like remaining in the processing chamber 201 are exhausted from the processing chamber 201 (purge).

[0120] As the source gas, various source gases exemplified in step a1 can be used.

[0121] [Step b2]

[0122] After step b1 is completed, an O-containing gas and an H-containing gas are supplied to the wafer 200 in the processing chamber 201, that is, the third layer formed on the wafer 200.

[0123] Specifically, the valves 243b and 243c are opened, and the O-containing gas and the H-containing gas are made to flow into the gas supply pipes 232b and 232c, respectively. The O-containing gas and the H-containing gas flowing into the gas supply pipes 232b and 232c are respectively adjusted in flow rate by the MFCs 241b and 241c, and are supplied into the processing chamber 201 via the nozzles 249b and 249a. The O-containing gas and the H-containing gas are mixed and reacted in the processing chamber 201, and then exhausted from the exhaust port 231a. At this time, atomic oxygen (O) and other oxidation species containing oxygen but not containing moisture (H 2 O) generated by the reaction of the O-containing gas and the H-containing gas are supplied to the wafer 200. At this time, the valves 243d and 243e can also be opened, and an inert gas can be supplied into the processing chamber 201 via the nozzles 249a and 249b.

[0124] In this step, the O-containing gas and the H-containing gas are supplied under the processing conditions for the third functional group contained in the first functional group bonded to Si and for the detachment of the first functional group bonded to Si in the third layer.

[0125] By performing this step under such processing conditions, the third functional group (including its residue) contained in the first functional group bonded to Si and the first functional group bonded to Si (including its residue) contained in the third layer can be detached from the third layer. Moreover, at least a part of the third layer formed on the wafer 200 can be oxidized (modified) to form a layer containing Si and O, i.e., a silicon oxide layer (SiO layer), as the fourth layer. The fourth layer becomes a layer with a lower content of impurities derived from the third functional group, the first functional group, and their residues compared to the third layer, i.e., a layer with a lower content of impurities such as C and H compared to the third layer. In addition, for the surface of the fourth layer, as a result of the oxidation treatment using an O-containing gas and an H-containing gas, it becomes a state terminated with OH, i.e., a state with adsorption sites formed. It should be noted that the impurities such as C and H detached from the third layer form a gaseous substance containing C, H, etc., which is exhausted from the processing chamber 201.

[0126] It should be noted that in this step, the third layer can be oxidized under processing conditions where the oxidizing power becomes higher (stronger) than that in step a2. Specifically, in this step, by using oxidation species such as atomic oxygen, the oxidizing power when oxidizing the third layer can be made higher than the oxidizing power when oxidizing the first layer in step a2. Thus, in step b2, the detachment of the third functional group (including its residue) contained in the first functional group bonded to Si and the first functional group bonded to Si (including its residue) contained in the third layer can be promoted respectively. In addition, when the second functional group (including its residue) is contained in the third layer, its detachment can also be promoted. As a result, the fourth layer can be made a layer with fewer impurities such as C, H, and N compared to the second layer.

[0127] After the fourth layer is formed, valves 243b and 243c are closed, and the supply of the O-containing gas and the H-containing gas into the processing chamber 201 is stopped respectively. Then, using the same processing steps as the purge in step a1, the gas remaining in the processing chamber 201 is exhausted (purged) from the processing chamber 201.

[0128] As the second oxidant, i.e., the O-containing gas + the H-containing gas, for example, O 2 gas + hydrogen (H 2 ) gas, ozone (O 3 ) gas + H 2 gas, hydrogen peroxide (H 2 O 2 ) gas + H 2 gas, water vapor (H 2 O gas) + H 2 gas, etc. can be used. At this time, as the H-containing gas, deuterium ( 2 H 2 ) gas can also be used instead of H 2 gas. It should be noted that in this specification, the so-called "O2 Gas + H 2 The juxtaposed description of two gases such as "gas" means H 2 Gas and O 2 Gas of the mixed gas. When supplying the mixed gas, the two gases can be mixed in the supply pipe (pre-mixed) and then supplied into the processing chamber 201, or the two gases can be separately supplied into the processing chamber 201 from different supply pipes and mixed in the processing chamber 201 (post-mixed). As the second oxidant, for example, O 3 Gas, H 2 O 2 Gas, H 2 O gas, plasma-excited O 2 Gas (O 2 *), etc. O-containing gases are used as reactive gases. As the second oxidant, one or more of these can be used.

[0129] [Number of implementation regulations]

[0130] By performing the cycles of steps b1 and b2 non-simultaneously, that is, asynchronously, for a specified number of times (n 2 times, n 2 is an integer of 1 or more), a second SiO film with a specified composition and a specified film thickness can be formed on the wafer 200. It is preferable to repeat the above cycles multiple times. That is, it is preferable that the thickness of the fourth layer formed by performing one cycle is less than the desired film thickness, and the above cycles are repeated multiple times until the film thickness of the second SiO film formed by laminating the fourth layer becomes the desired film thickness. The thickness of the second SiO film can be set, for example, to be 0.1 nm or more and 5 nm or less, and preferably set to a thickness in the range of 0.5 nm or more and 3 nm or less.

[0131] It should be noted that compared with the above-mentioned first SiO film, the second SiO film becomes a film with excellent processability (such as wet etching resistance, hereinafter simply referred to as etching resistance). This is because in step b2, O-containing gas and H-containing gas are used as the second oxidant, so that the oxidizing power when oxidizing the third layer is higher than the oxidizing power when oxidizing the first layer in step a2. Thus, the second SiO film can be made into a film with fewer impurities such as C, H, and N compared with the first SiO film. In addition, thereby, the arrangement of the atoms constituting the second SiO film can be adjusted, the distance between the atoms constituting the second SiO film can be made shorter than the distance between the atoms constituting the first SiO film, and the bonding between the atoms constituting the second SiO film can be made stronger than the bonding between the atoms constituting the first SiO film. As a result, the molecular structure of the second SiO film can be made closer to a stable state than the molecular structure of the first SiO film. As these results, the second SiO film becomes a film with excellent processability compared with the first SiO film.

[0132] 〔Alternate implementation of steps A and B〕

[0133] By alternately performing the above steps A and B in a specified order a specified number of times, as Figure 6 shown, a SiO film (stacked SiO film), which is an oxide film (stacked oxide film) formed by alternately laminating the first SiO film and the second SiO film, can be formed on the wafer 200.

[0134] As described above, for the first SiO film, compared with the second SiO film, it has excellent in-plane film thickness uniformity and step coverage on the wafer surface. In addition, it has the characteristic of maintaining the substrate oxidation amount in a good state. In addition, compared with the first SiO film, the second SiO film has excellent processability. For these reasons, the stacked oxide film having a stacked structure (laminated structure) of the first SiO film and the second SiO film becomes a film that simultaneously has the above characteristics, that is, a film with excellent in-plane film thickness uniformity and step coverage on the wafer surface, and has the characteristic of maintaining the substrate oxidation amount in a good state, and in addition, has excellent processability.

[0135] It should be noted that by setting the film thickness of at least any one of the first SiO film and the second SiO film, preferably the film thicknesses of both films, to be in the range of 0.1 nm or more and 5 nm or less, preferably 0.5 nm or more and 3 nm or less, more preferably 0.5 nm or more and 2 nm or less, and further preferably 0.5 nm or more and 1.5 nm or less, a stacked oxide film that appropriately combines the respective characteristics of the first SiO film and the second SiO film, that is, excellent in-plane film thickness uniformity, step coverage, processability, substrate oxidation inhibition effect, etc., can be formed.

[0136] It should be noted that as Figure 6 shown, when forming the stacked oxide film, it is preferable to perform step A first so as to form the first SiO film on the wafer 200 first. In addition, when forming the stacked oxide film, it is preferable to perform step B last so as to form the second SiO film last. That is, as Figure 6 shown, it is preferable to set the lowermost film of the stacked oxide film as the first SiO film and the uppermost film of the stacked oxide film as the second SiO film.

[0137] (Processing conditions)

[0138] The specific processing conditions in steps A and B are exemplified below. In the following description, the expression of a numerical range such as "1 to 2666 Pa" means that the lower limit value and the upper limit value are included in the range. Therefore, for example, "1 to 2666 Pa" means "1 Pa or more and 2666 Pa or less". The same applies to other numerical ranges. In addition, in this specification, the so-called processing temperature refers to the temperature of the wafer 200, and the so-called processing pressure refers to the pressure in the processing chamber 201. In addition, the so-called gas supply flow rate: 0 sccm means that no gas is supplied. The same applies in the following description.

[0139] As the processing conditions in step a1, the following can be exemplified:

[0140] Raw material gas supply flow rate: 0.01 to 2 slm, preferably 0.1 to 1 slm

[0141] Raw material gas supply time: 1 to 120 seconds, preferably 1 to 60 seconds

[0142] Inert gas supply flow rate (each gas supply pipe): 0 to 10 slm

[0143] Processing temperature: 550 to 700 °C, preferably 600 to 650 °C

[0144] Processing pressure: 1 to 2666 Pa, preferably 67 to 1333 Pa.

[0145] As the processing conditions in step a2, the following can be exemplified:

[0146] O-containing gas supply flow rate: 0.1 to 10 slm

[0147] O-containing gas supply time: 1 to 120 seconds, preferably 1 to 60 seconds

[0148] Processing pressure: 1 to 4000 Pa, preferably 1 to 3000 Pa.

[0149] Other processing conditions can be set to the same processing conditions as those in step a1.

[0150] As the processing conditions in step b1, the following can be exemplified:

[0151] Raw material gas supply flow rate: 0.01 to 2 slm, preferably 0.1 to 1 slm

[0152] Raw material gas supply time: 1 to 120 seconds, preferably 1 to 60 seconds

[0153] Inert gas supply flow rate (each gas supply pipe): 0 to 10 slm

[0154] Processing temperature: 550 to 700 °C, preferably 600 to 650 °C

[0155] Processing pressure: 1 to 2666 Pa, preferably 67 to 1333 Pa.

[0156] As the processing conditions in step b2, the following can be exemplified:

[0157] Supply flow rate of O-containing gas: 0.1 to 10 slm

[0158] Supply flow rate of H-containing gas: 0.1 to 10 slm

[0159] Supply time of each gas: 1 to 120 seconds, preferably 1 to 60 seconds

[0160] Processing pressure: 1 to 2000 Pa, preferably 1 to 1333 Pa.

[0161] Other processing conditions can be set to be the same as those in step b1.

[0162] It should be noted that if the processing temperature becomes less than 550 °C, the following situation exists: in the first SiO film and the second SiO film formed on the wafer 200, impurities such as C, H, N from the first functional group, the second functional group, the third functional group, and their residues become likely to remain, and the processability resistance, that is, the etching resistance of the stacked oxide film formed on the wafer 200 decreases. By setting the processing temperature to a temperature of 550 °C or higher, the decrease in the etching resistance of the first SiO film can be compensated by the high etching resistance of the second SiO film, and the etching resistance of the entire stacked oxide film can reach a practical level. By setting the processing temperature to a temperature of 600 °C or higher, the effects described herein can be further improved.

[0163] In addition, if the processing temperature exceeds 700 °C, the following situation exists: the in-plane film thickness uniformity and step coverage of the entire stacked oxide film deteriorate, and in addition, the amount of substrate oxidation becomes excessive, and they are respectively lower than the practical level. By setting the processing temperature to a temperature of 700 °C or lower, the high in-plane film thickness uniformity and step coverage of the first SiO film can be used to compensate for the decrease in the in-plane film thickness uniformity and step coverage of the second SiO film respectively, and the in-plane film thickness uniformity and step coverage of the entire stacked oxide film can reach a practical level. In addition, the amount of substrate oxidation can reach a practical level. By setting the processing temperature to 650 °C or lower, the effects described herein can be further improved.

[0164] (Post-purge and atmospheric pressure recovery)

[0165] After forming a stacked oxide film of a desired thickness on the wafer 200, an inert gas as a purge gas is supplied into the processing chamber 201 from each of the nozzles 249a and 249b, and exhausted from the exhaust port 231a. Thereby, the inside of the processing chamber 201 is purged, and gases, reaction by-products, etc. remaining in the processing chamber 201 are removed from the processing chamber 201 (post-purge). After that, the atmosphere inside the processing chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure inside the processing chamber 201 is restored to normal pressure (atmospheric pressure restoration).

[0166] (Cassette unloading, wafer removal)

[0167] Thereafter, the seal cover 219 is lowered by the cassette elevator 115, and the lower end of the manifold 209 is opened. And the processed wafer 200 is carried out from the lower end of the manifold 209 to the outside of the reaction tube 203 in a state of being supported by the cassette 217 (cassette unloading). After the cassette unloading, the gate 219s is moved, and the lower end opening of the manifold 209 is sealed by the gate 219s with the O-ring 220c (gate closing). The processed wafer 200 is removed from the cassette 217 after being carried out to the outside of the reaction tube 203 (wafer removal).

[0168] (3) Effects of this method

[0169] According to this method, one or more of the following effects can be obtained.

[0170] (a) In step A, the base oxidation amount can be maintained in a good state, and the first SiO film having better in-wafer film thickness uniformity and step coverage than the second SiO film can be formed. In addition, in step B, the second SiO film having better process resistance than the first SiO film can be formed. In this method, by alternately performing these steps a specified number of times, the base oxidation amount can be maintained in a good state, and the stacked oxide film formed on the wafer 200 can be made into a film having excellent in-wafer film thickness uniformity, step coverage, and process resistance.

[0171] (b) In step a1 and step b1, by using the above raw material gases, the outermost surfaces of the first layer and the third layer can be respectively capped with the chemically stable first functional groups, which can prevent the adsorption of at least one of atoms and molecules to the Si adsorbed on the surface of the wafer 200, and prevent the adsorption of at least one of atoms and molecules to the adsorption sites (OH-capped) on the surrounding surface of the wafer 200. As a result, the in-wafer thickness uniformity and step coverage of the first layer and the third layer can be respectively improved, and the stacked oxide film formed on the wafer 200 can be made into a film having excellent in-wafer film thickness uniformity and step coverage.

[0172] (c) In steps a1 and b1, a source gas is supplied under processing conditions where the Si in a state where the first functional group does not detach from the Si contained in the raw material while the second functional group detaches, and the second functional group detaches and the bond with the first functional group is maintained, adsorbs to the surface of the wafer 200. Thereby, the outermost surfaces of the first layer and the third layer can be respectively capped with the chemically stable first functional group. As a result, the in-plane thickness uniformity and step coverage of the first layer and the third layer can be respectively improved, and the stacked oxide film formed on the wafer 200 can be made into a film with excellent in-plane film thickness uniformity and step coverage.

[0173] (d) In steps a1 and b1, a raw material is supplied under processing conditions where the adsorption of Si in a state where the second functional group detaches from the Si and the bond with the first functional group is maintained to the surface of the wafer 200 is dominant (advantageous) compared to the adsorption of the second functional group that has detached from the Si to the surface of the wafer 200. Thereby, the amount (concentration) of impurities from the second functional group that can be trapped in the first layer and the third layer can be respectively reduced, and the outermost surfaces of the first layer and the third layer can be respectively capped with the chemically stable first functional group. As a result, the stacked oxide film formed on the wafer 200 can have excellent process tolerance, and in addition, a film with excellent in-plane film thickness uniformity and step coverage can be formed.

[0174] (e) In steps a1 and b1, using the first functional group bonded to the Si adsorbed on the surface of the wafer 200, the adsorption of at least one of atoms and molecules to the Si adsorbed on the surface of the wafer 200 is hindered, and the adsorption of at least one of atoms and molecules to the adsorption site (OH-capped) on the surrounding surface of the wafer 200 is hindered. Thereby, the in-plane thickness uniformity and step coverage of the first layer and the third layer can be respectively improved, and the stacked oxide film formed on the wafer 200 can be made into a film with excellent in-plane film thickness uniformity and step coverage.

[0175] (f) In steps a1 and b1, using the first functional group bonded to the Si adsorbed on the surface of the wafer 200, the adsorption site (OH-capped) on the surrounding surface of the wafer 200 is maintained. Thereby, the in-plane thickness uniformity and step coverage of the first layer and the third layer can be respectively improved, and the stacked oxide film formed on the wafer 200 can be made into a film with excellent in-plane film thickness uniformity and step coverage.

[0176] (g) In steps a1 and b1, Si can be adsorbed to the surface of the wafer 200 discontinuously, that is, in a thickness less than 1 atomic layer. Thereby, the in-plane thickness uniformity and step coverage of the first layer and the third layer can be respectively improved, and the stacked oxide film formed on the wafer 200 can be made into a film with excellent in-plane film thickness uniformity and step coverage.

[0177] (h) In steps a1 and b1, when continuously supplying the raw material gas until the adsorption reaction (chemical adsorption reaction) of Si on the surface of the wafer 200 is saturated, the in-plane thickness uniformity and step coverage of the first layer and the third layer can be improved respectively. This is because, in the state where the adsorption reaction of Si on the surface of the wafer 200 is saturated, the layer composed of Si adsorbed on the surface of the wafer 200 becomes a discontinuous layer with a thickness less than 1 atomic layer. In addition, the adsorption sites (OH-terminated) on a part of the surface of the wafer 200 are maintained, and in addition, the surface of the wafer 200 becomes a state covered by the first functional group. As a result, the stacked oxide film formed on the wafer 200 can be made into a film with more excellent in-plane film thickness uniformity and step coverage.

[0178] (i) In step a2, an oxygen-containing gas is supplied under the treatment conditions in which at least one of the third functional group contained in the first functional group bonded to Si in the first layer and the first functional group bonded to Si is detached. In step b2, an oxygen-containing gas and a hydrogen-containing gas are supplied under the treatment conditions in which the third functional group contained in the first functional group bonded to Si in the third layer and the first functional group bonded to Si are detached. Thereby, the amount (concentration) of impurities such as the first functional group, the third functional group, and their residues contained in the first layer and the third layer can be reduced respectively, and adsorption sites are formed on the outermost surfaces of the first layer and the third layer. As a result, the stacked oxide film formed on the wafer 200 can be made into a film with excellent processability and excellent in-plane film thickness uniformity and step coverage.

[0179] (j) When forming the stacked oxide film, if step A is performed first to form the first SiO film on the wafer 200 first, oxidation of the substrate and the surface of the wafer 200 at this time can be suppressed. Thereafter, while making the first formed first SiO film function as an oxidation barrier layer, the second SiO film can be formed to suppress oxidation of the substrate at this time. Thereby, oxidation of the substrate when forming the stacked oxide film can be suppressed.

[0180] In addition, when forming the stacked oxide film, if step A is performed first to form the first SiO film on the wafer 200 first, the excellent characteristics of the first formed first SiO film, that is, the in-plane film thickness uniformity and step coverage, can be inherited to the film formed on the first SiO film thereafter, and the in-plane film thickness uniformity and step coverage of the finally formed stacked oxide film can be improved.

[0181] (k) Further, when forming the stacked oxide film, if step B is performed last to finally form the second SiO film, the outermost surface of the finally formed stacked oxide film can be made into the second SiO film with excellent process resistance. Thus, the process resistance of the outermost surface of the finally formed stacked oxide film can be improved, and the process resistance of the entire stacked oxide film can be improved.

[0182] In addition, when forming the stacked oxide film, if step B is performed last to finally form the second SiO film, the first SiO film that becomes the lower layer of the second SiO film can be modified to improve the process resistance, and the process resistance of the entire stacked oxide film can be further improved. It should be noted that the effects described here can also be said to be the effects brought about by the sequential formation of the first SiO film and the second SiO film, that is, the effects brought about by forming the second SiO film on the first SiO film.

[0183] In the case of wanting to obtain the above effects, preferably, when forming the stacked oxide film, step A is performed first and step B is performed last, as in the following film formation sequence. It should be noted that n in the following film formation sequence 1 , n 2 , n 3 each represents an integer of 1 or more.

[0184] [(source gas → oxygen-containing gas) × n 1 → (source gas → oxygen-containing gas + hydrogen-containing gas) × n 2 × n 3

[0185] (l) The effects brought about by this method can also be obtained when using the above various source gases, when using the above various oxidants, and when using the above various inert gases.

[0186] (4) Variation

[0187] The substrate treatment sequence in this method can be changed as in the following variation.

[0188] (Variation 1)

[0189] As Figure 7 shown, when forming the stacked oxide film, step A and step B can also be alternately repeated, so that the first SiO film formed first (initially) is thicker than the second SiO film formed first (initially).

[0190] According to this variation, the same effects as those of the above method can be obtained.

[0191] In addition, by making the thickness of the first (initial) formed first SiO film thicker than the thickness of the first (initial) formed second SiO film, oxidation of the substrate, i.e., the substrate at the earliest (initial) stage where the surface of the wafer 200 is prone to oxidation, can be suppressed.

[0192] In addition, by making the thickness of the first (initial) formed first SiO film thicker than the thickness of the first (initial) formed second SiO film, it is easy to inherit the excellent in-plane film thickness uniformity and step coverage of the first (initial) formed first SiO film to the entire stacked oxide film, and the in-plane film thickness uniformity and step coverage of the finally formed stacked oxide film can be further improved.

[0193] It should be noted that in this case, if the first SiO film with excellent in-plane film thickness uniformity and step coverage is formed first, the in-plane film thickness uniformity and step coverage of the finally formed stacked oxide film can be further improved.

[0194] (Modification Example 2)

[0195] As Figure 7 shown, when forming the stacked oxide film, steps A and B can also be alternately repeated so that the last (later) formed second SiO film is thicker than the last (later) formed first SiO film.

[0196] According to this modification example, the same effect as the above method can be obtained.

[0197] In addition, by making the thickness of the last (later) formed second SiO film thicker than the thickness of the last (later) formed first SiO film, the processability on the outermost surface side of the finally formed stacked oxide film can be improved, and the processability of the entire stacked oxide film can be improved.

[0198] It should be noted that at this time, if the second SiO film with excellent processability is formed last, the processability of the finally formed stacked oxide film can be further improved.

[0199] (Modification Example 3)

[0200] As Figure 7 shown, when forming the stacked oxide film, as steps A and B are alternately repeated, the ratio of the thickness of the first SiO film to the thickness of the second SiO film can gradually decrease. That is, the ratio of the thickness of the second SiO film to the thickness of the first SiO film can increase in stages.

[0201] According to this modification example, the same effect as the above method can be obtained.

[0202] In addition, in the thickness direction of the stacked oxide film, instead of causing the characteristics of the film to change abruptly, layers can be formed in such a way that the characteristics of the film change in stages, and the above-described effects in the modification can be obtained with good balance over the entire stacked oxide film. It should be noted that in the thickness direction of the stacked oxide film, by forming such layers, the oxidation of the substrate is suppressed in the initial stage of film formation, and the effect of improving the in-plane film thickness uniformity and step coverage on the wafer surface becomes stronger. In the later stage of film formation, the effect of improving the processability becomes stronger. That is, the oxidation of the substrate of the stacked oxide film is suppressed. In particular, the lower part of the stacked oxide film becomes a film having excellent in-plane film thickness uniformity and step coverage characteristics. In particular, the upper part of the stacked oxide film becomes a film having excellent processability. It should be noted that the upper part of the stacked oxide film has a tendency to transfer the characteristics to the lower part (the initially formed oxide film) of the stacked oxide film, whereby the in-plane film thickness uniformity and step coverage of the entire stacked oxide film become good.

[0203] (Modification 4)

[0204] In the gas supply sequence as shown below, when forming the stacked oxide film, after the O-containing gas is supplied to the wafer 200 in advance (pre-flow), steps A and B can be alternately performed a specified number of times.

[0205] O-containing gas → (source gas → O-containing gas) × n 1 → (source gas → O-containing gas + H-containing gas) × n 2 → ···

[0206] According to this modification, the same effects as the above-described method can be obtained.

[0207] In addition, by pre-flowing the O-containing gas to the wafer 200, the adsorption sites (OH-terminated) on the surface of the wafer 200 before forming the stacked oxide film can be optimized. Thereby, the formation of the first SiO film and the second SiO film is promoted, and the formation time when forming the stacked oxide film can be shortened. It should be noted that the processing conditions at this time can be set to be the same as those in step a2. Among them, it is preferable that the O-containing gas supply time is set to be longer than the O-containing gas supply time in step a2. For example, the O-containing gas supply time when pre-flowing the O-containing gas can be set to 30 to 300 seconds, and preferably can be set to 60 to 180 seconds.

[0208] <Other aspects of the present invention>

[0209] The above has specifically described the embodiments of the present invention. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist thereof.

[0210] For example, in at least one of step A of forming the first SiO film and step B of forming the second SiO film, ammonia (NH 3 ) gas or other N and H-containing gases can be supplied to the wafer 200. The N and H-containing gases are both N-containing gases and H-containing gases. The N and H-containing gases can be supplied from the above H-containing gas supply system. The processing steps and conditions in the step of supplying the N and H-containing gases can be set to be the same as those in steps a2 and b2 in the above method.

[0211] At this time, any one of the following can be formed on the wafer 200: an N-containing SiO film formed by alternately laminating an N-containing first SiO film and an N-containing second SiO film, an N-containing SiO film formed by alternately laminating an N-containing first SiO film and a second SiO film, or an N-containing SiO film formed by alternately laminating a first SiO film and an N-containing second SiO film. In any case, the same effect as the above method can be obtained.

[0212] In addition, for example, in at least one of step A of forming the first SiO film and step B of forming the second SiO film, a step of supplying a C- and H-containing gas such as propylene (C 3 H 6 ) gas to the wafer 200 can be performed. The C- and H-containing gas is both a C-containing gas and an H-containing gas. The C- and H-containing gas can be supplied from the above raw material gas supply system. The processing steps and conditions in the step of supplying the C- and H-containing gas can be set to be the same as those in steps a2 and b2 in the above method.

[0213] At this time, any one of the following can be formed on the wafer 200: a C-containing SiO film formed by alternately laminating a C-containing first SiO film and a C-containing second SiO film, a C-containing SiO film formed by alternately laminating a C-containing first SiO film and a second SiO film, or a C-containing SiO film formed by alternately laminating a first SiO film and a C-containing second SiO film. In any case, the same effect as the above method can be obtained.

[0214] In addition, for example, in at least one of step A of forming the first SiO film and step B of forming the second SiO film, a step of supplying a C- and H-containing gas such as C 3 H 6 gas to the wafer 200 can be performed, and a step of supplying NH 3Steps for gases containing N and H such as gases. The gases containing C and H can be supplied from the above raw material gas supply system, and the gases containing N and H can be supplied from the above H-containing gas supply system. The processing steps and processing conditions in the steps of supplying the gases containing C and H and the steps of supplying the gases containing N and H can be respectively set to be the same as those in steps a2 and b2 of the above method.

[0215] At this time, any one of the following can be formed on the wafer 200: a SiO film containing C and N formed by alternately laminating a first SiO film containing C and N and a second SiO film containing C and N; a SiO film containing C and N formed by alternately laminating a first SiO film containing C and N and a second SiO film; a SiO film containing C and N formed by alternately laminating a first SiO film and a second SiO film containing C and N. In any case, the same effect as the above method can be obtained.

[0216] In addition, for example, a step of supplying a B-containing gas such as boron trichloride (BCl 3 ) gas to the wafer 200 can be performed using at least any one of the step A of forming the first SiO film and the step B of forming the second SiO film. The B-containing gas can be supplied from the above raw material gas supply system. The processing steps and processing conditions in the step of supplying the B-containing gas can be set to be the same as those in steps a2 and b2 of the above method.

[0217] At this time, any one of the following can be formed on the wafer 200: a SiO film containing B formed by alternately laminating a first SiO film containing B and a second SiO film containing B; a SiO film containing B formed by alternately laminating a first SiO film containing B and a second SiO film; a SiO film containing B formed by alternately laminating a first SiO film and a second SiO film containing B. In any case, the same effect as the above method can be obtained.

[0218] The atom X contained in the raw material gas can be a metal element such as aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), molybdenum (Mo), tungsten (W), ruthenium (Ru). In these cases, a laminated metal oxide film such as an aluminum oxide film (AlO film), a titanium oxide film (TiO film), a zirconium oxide film (ZrO film), a hafnium oxide film (HfO film), a tantalum oxide film (TaO film), a molybdenum oxide film (MoO film), a tungsten oxide film (WO film), a ruthenium oxide film (RuO film) can be formed on the wafer 200. The processing steps and processing conditions in these cases can be set to be the same as those in the above method. In these cases, the same effect as the above method can also be obtained.

[0219] Preferably, the processes used in each process are prepared in advance corresponding to the process content separately and stored in the storage device 121c via an electrical communication line and an external storage device 123. Further, when starting each process, it is preferable that the CPU 121a appropriately selects a suitable process from among a plurality of processes stored in the storage device 121c corresponding to the process content. Thereby, it is possible to form films having various film types, composition ratios, film qualities, and film thicknesses with good reproducibility using one substrate processing apparatus. In addition, the burden on the operator can be reduced, operation errors can be avoided, and each process can be started promptly.

[0220] The above-described processes are not limited to newly created ones. For example, they can also be prepared by changing existing processes already installed in the substrate processing apparatus. In the case of changing a process, the changed process can also be installed in the substrate processing apparatus via an electrical communication line and a recording medium on which the process is recorded. In addition, the input / output device 122 provided in the existing substrate processing apparatus can be operated to directly change the existing processes already installed in the substrate processing apparatus.

[0221] In the above-described manner, an example of forming a film by a batch-type substrate processing apparatus that processes a plurality of substrates at a time has been described. The present invention is not limited to the above-described manner. For example, it can also be preferably applied to a case of forming a film using a single-substrate processing apparatus that processes one or several substrates at a time. In addition, in the above-described manner, an example of forming a film by a substrate processing apparatus having a hot-wall type processing furnace has been described. The present invention is not limited to the above-described manner and can also be preferably applied to a case of forming a film using a substrate processing apparatus having a cold-wall type processing furnace.

[0222] When using these substrate processing apparatuses, each process can also be performed using the same processing steps and processing conditions as those in the above-described manner and modified examples, and the same effects as those in the above-described manner and modified examples can be obtained.

[0223] In addition, the above-described manner and modified examples can also be used in appropriate combination. The processing steps and processing conditions at this time can be the same as, for example, the processing steps and processing conditions of the above-described manner and modified examples.

Claims

1. A substrate processing method, comprising steps of performing the following (a) and (b) to form an oxide film formed by laminating a first oxide film and a second oxide film on the substrate: (a) A step of forming the first oxide film containing atom X by performing a cycle including the following (a1) and (a2) n 1 times: (a1) A step of supplying a raw material having a partial structure in which a first functional group and a second functional group are directly bonded to atom X, and the bond energy between the first functional group and atom X is higher than the bond energy between the second functional group and atom X to the substrate, and forming a first layer containing a component in which the first functional group is bonded to atom X, Wherein, The first functional group contains an alkoxy group, and the second functional group contains at least any one of an amino group, an alkyl group, a halogenated group, a hydroxyl group, a hydrogen group, an aryl group, a vinyl group, and a nitro group; and (a2) supplying a first oxidant to the substrate to oxidize the first layer and form a second layer containing the atom X and oxygen; and (b) Forming the second oxide film containing the atom X by performing the cycle including the following (b1) and (b2) n 2 times: (b1) A step of supplying the raw material to the substrate to form a third layer containing a component in which the first functional group is bonded to the atom X; and (b2) A step of supplying a second oxidant to the substrate under processing conditions where the oxidizing power is higher than the oxidizing power when oxidizing the first layer in (a2), and oxidizing the third layer to form a fourth layer containing the atom X and oxygen. wherein, the n 1 is an integer of 1 or more, and the n 2 is an integer of 1 or more.

2. A substrate processing method, comprising steps of performing the following (a) and (b) to form an oxide film formed by laminating a first oxide film and a second oxide film on the substrate: (a) A step of forming the first oxide film containing atom X by performing the cycle including the following (a1) and (a2) n 1 times: (a1) A step of supplying a raw material having a partial structure in which a first functional group and a second functional group are directly bonded to atom X and the bond energy between the first functional group and atom X is higher than the bond energy between the second functional group and atom X to the substrate, and forming a first layer containing a component in which the first functional group is bonded to atom X; and (a2) A step of supplying a first oxidant to the substrate to oxidize the first layer and form a second layer containing atom X and oxygen; and (b) A step of forming the second oxide film containing the atom X by repeating a cycle including the following (b1) and (b2) n 2 times: (b1) A step of supplying the raw material to the substrate to form a third layer containing a component in which the first functional group is bonded to the atom X; and (b2) A step of supplying a second oxidizing agent to the substrate under treatment conditions where the oxidizing power is higher than the oxidizing power when oxidizing the first layer in (a2), and oxidizing the third layer to form a fourth layer containing the atom X and oxygen. Wherein, The atom X has 4 bonding sites, 3 of the 4 bonding sites of the atom X are each bonded to the first functional group, and the remaining 1 of the 4 bonding sites of the atom X is bonded to the second functional group. In (a1) and (b1), the raw material is supplied under the processing conditions of adsorbing the atom X on the surface of the substrate in a state where the first functional group is bonded to each of the 3 bonding sites of the atom X. Said n 1 is an integer of 1 or more, and said n 2 is an integer of 1 or more.

3. The substrate processing method according to claim 1, Wherein, In (a1) and (b1), the raw material is supplied under the following conditions: the first functional group does not detach from the atom X contained in the raw material while the second functional group detaches, and the atom X in a state where the second functional group detaches and the bonding with the first functional group is maintained adsorbs on the surface of the substrate.

4. The substrate processing method according to claim 3, Wherein, In (a1) and (b1), the raw material is supplied under the following conditions: compared with the adsorption of the second functional group that has detached from the atom X on the surface of the substrate, the adsorption of the atom X in a state where the second functional group detaches and the bonding with the first functional group is maintained on the surface of the substrate is dominant.

5. The substrate processing method according to claim 2, Wherein, In (a1) and (b1), the first functional group bonded to the atom X adsorbed on the surface of the substrate is used to hinder the adsorption of at least any one of atoms and molecules to the atom X adsorbed on the surface of the substrate, and to hinder the adsorption of at least any one of atoms and molecules to the adsorption sites on the surface of the substrate around it.

6. The substrate processing method according to claim 2, Wherein, In (a1) and (b1), the first functional group bonded to the atom X adsorbed on the surface of the substrate is used to maintain the adsorption sites on the surface of the substrate around it.

7. The substrate processing method according to claim 2, Wherein, In (a1) and (b1), the atom X is adsorbed on the surface of the substrate discontinuously.

8. The substrate processing method according to claim 2, Wherein, In (a1) and (b1), the raw material is continuously supplied until the adsorption reaction of the atom X on the surface of the substrate reaches saturation.

9. The substrate processing method according to claim 8, Wherein, In a state where the adsorption reaction of the atom X to the surface of the substrate is saturated, the thickness of the layer composed of the atom X adsorbed on the surface of the substrate is less than 1 atomic layer.

10. The substrate processing method according to claim 8, wherein, in a state where the adsorption reaction of the atom X to the surface of the substrate is saturated, a part of the surface of the substrate is maintained as an adsorption site.

11. The substrate processing method according to claim 8, wherein, in a state where the adsorption reaction of the atom X to the surface of the substrate is saturated, the surface of the substrate becomes a state covered with the first functional group.

12. The substrate processing method according to claim 1, wherein, in (a2), under the processing conditions in which at least any one of the third functional group contained in the first functional group bonded to the atom X in the first layer and the first functional group bonded to the atom X is detached, the first oxidant is supplied, in (b2), under the processing conditions in which the third functional group contained in the first functional group bonded to the atom X in the third layer and the first functional group bonded to the atom X are detached, the second oxidant is supplied.

13. The substrate processing method according to claim 1, wherein, The first oxidant contains O 2 gas, NO gas, N 2 O gas, NO 2 gas, at least any one of them, and the second oxidant contains O 2 gas + H 2 gas, O 3 gas + H 2 gas, H 2 O 2 gas + H 2 gas, H 2 O + H 2 gas, O 3 gas, H 2 O 2 gas, H 2 gas, plasma-excited O 2 gas, at least any one of them.

14. The substrate processing method according to claim 1, wherein, the processing temperature in (a) is set to 550 °C or higher and 700 °C or lower, the processing temperature in (b) is set to 550 °C or higher and 700 °C or lower.

15. The substrate processing method according to claim 1, wherein, in the step of forming the oxide film, the first oxide film is formed first.

16. The substrate processing method according to claim 1, wherein, in the step of forming the oxide film, the second oxide film is formed last.

17. The substrate processing method according to claim 1, wherein, in the step of forming the oxide film, (a) and (b) are alternately repeated so that the first formed first oxide film is thicker than the first formed second oxide film.

18. The substrate processing method according to claim 1, wherein, in the step of forming the oxide film, (a) and (b) are alternately repeated so that the last formed second oxide film is thicker than the last formed first oxide film.

19. The substrate processing method according to claim 17, wherein, as (a) and (b) are alternately repeated, the ratio of the thickness of the first oxide film to the thickness of the second oxide film gradually decreases.

20. A method for manufacturing a semiconductor device, which has a step of performing the following (a) and (b) to form an oxide film formed by laminating a first oxide film and a second oxide film on a substrate: (a) A step of forming the first oxide film containing atom X by performing the cycle including the following (a1) and (a2) for n 1 times: (a1) A step of supplying a raw material having a partial structure in which a first functional group and a second functional group are directly bonded to atom X and the bond energy between the first functional group and atom X is higher than the bond energy between the second functional group and atom X to the substrate, and forming a first layer containing a component in which the first functional group is bonded to atom X. wherein, the first functional group contains an alkoxy group, the second functional group contains at least any one of an amino group, an alkyl group, a halogenated group, a hydroxyl group, a hydrogen group, an aryl group, a vinyl group, and a nitro group; and (a2) a step of supplying a first oxidant to the substrate to oxidize the first layer and form a second layer containing the atom X and oxygen; and (b) A step of forming the second oxide film containing the atom X by performing the cycle including the following (b1) and (b2) n 2 times: (b1) A step of supplying the raw material to the substrate to form a third layer containing a component in which the first functional group is bonded to the atom X; and (b2) A step of supplying a second oxidant to the substrate under processing conditions where the oxidizing power becomes higher than the oxidizing power when oxidizing the first layer in (a2) to oxidize the third layer to form a fourth layer containing the atom X and oxygen. Said n 1 is an integer of 1 or more, and said n 2 is an integer of 1 or more.

21. A method of manufacturing a semiconductor device, the method having a step of performing the following (a) and (b) to form an oxide film in which a first oxide film and a second oxide film are stacked on a substrate: (a) A step of forming the first oxide film containing atom X by performing the cycle including the following (a1) and (a2) n 1 times: (a1) A step of supplying a raw material having a partial structure in which a first functional group and a second functional group are directly bonded to the atom X to the substrate, and the bond energy between the first functional group and the atom X is higher than the bond energy between the second functional group and the atom X, and forming a first layer containing a component in which the first functional group is bonded to the atom X; and (a2) A step of supplying a first oxidizing agent to the substrate to oxidize the first layer and form a second layer containing the atom X and oxygen; and (b) A step of forming the second oxide film containing the atom X by performing the cycle including the following (b1) and (b2) n 2 times: (b1) A step of supplying the raw material to the substrate to form a third layer containing a component in which the first functional group is bonded to the atom X; and (b2) A step of supplying a second oxidant to the substrate under treatment conditions where the oxidizing power is higher than the oxidizing power when oxidizing the first layer in (a2), and oxidizing the third layer to form a fourth layer containing the atom X and oxygen. Wherein, The atom X has 4 bonding sites, and 3 of the 4 bonding sites of the atom X are each bonded to the first functional group, and the remaining 1 bonding site of the 4 bonding sites of the atom X is bonded to the second functional group, In (a1) and (b1), the raw material is supplied under the processing conditions in which the atom X is adsorbed on the surface of the substrate in a state where the first functional group is bonded to each of the 3 bonding sites of the atom X, Said n 1 is an integer of 1 or more, and said n 2 is an integer of 1 or more.

22. A substrate processing apparatus, comprising: A raw material supply system that supplies a substrate with a raw material having a partial structure in which a first functional group and a second functional group are directly bonded to an atom X, and the bond energy between the first functional group and the atom X is higher than the bond energy between the second functional group and the atom X, Wherein, The first functional group includes an alkoxy group, and the second functional group includes at least any one of an amino group, an alkyl group, a halogenated group, a hydroxyl group, a hydrogen group, an aryl group, a vinyl group, and a nitro group; A first oxidant supply system that supplies a first oxidant to the substrate; A second oxidant supply system that supplies a second oxidant to the substrate; A heater that heats the substrate; and A control unit configured to be able to control the raw material supply system, the first oxidant supply system, the second oxidant supply system, and the heater to perform the following processing, which is to perform the following (a) and (b) to form an oxide film in which a first oxide film and a second oxide film are stacked on the substrate: (a) A process for forming the first oxide film containing the atom X by performing the cycle including the following (a1) and (a2) n 1 times: (a1) A process of supplying the raw material to the substrate to form a first layer containing a component in which the first functional group is bonded to the atom X; and (a2) A process of supplying the first oxidant to the substrate to oxidize the first layer to form a second layer containing the atom X and oxygen; And (b) Forming the second oxide film containing the atom X by performing the cycle including the following (b1) and (b2) n 2 times: (b1) A process of supplying the raw material to the substrate to form a third layer containing a component in which the first functional group is bonded to the atom X; and (b2) A process of supplying the second oxidant to the substrate under treatment conditions where the oxidizing power is higher than the oxidizing power when oxidizing the first layer in (a2), oxidizing the third layer, and forming a fourth layer containing the atom X and oxygen. wherein, the n 1 is an integer of 1 or more, and the n 2 is an integer of 1 or more.

23. A substrate processing apparatus, comprising: A raw material supply system that supplies a substrate with a raw material having a partial structure in which a first functional group and a second functional group are directly bonded to an atom X, and the bond energy between the first functional group and the atom X is higher than the bond energy between the second functional group and the atom X; A first oxidant supply system that supplies a first oxidant to the substrate; A second oxidant supply system that supplies a second oxidant to the substrate; A heater that heats the substrate; and A control unit configured to be able to control the raw material supply system, the first oxidant supply system, the second oxidant supply system, and the heater to perform the following processing, which is to perform the following (a) and (b) to form an oxide film in which a first oxide film and a second oxide film are stacked on the substrate: (a) A process for forming the first oxide film containing the atom X by repeating the cycle including the following (a1) and (a2) n 1 times: (a1) A process of supplying the raw material to the substrate to form a first layer containing a component in which the first functional group is bonded to the atom X; and (a2) A process of supplying the first oxidant to the substrate to oxidize the first layer to form a second layer containing the atom X and oxygen; and (b) The process of forming the second oxide film containing the atom X by performing the cycle including the following (b1) and (b2) for n 2 times: (b1) a process of supplying the raw material to the substrate to form a third layer containing a component in which the first functional group is bonded to the atom X; and (b2) a process of supplying the second oxidant to the substrate under processing conditions where the oxidizing power is higher than the oxidizing power when oxidizing the first layer in (a2), and oxidizing the third layer to form a fourth layer containing the atom X and oxygen, Wherein, The atom X has 4 bonding sites, and 3 of the 4 bonding sites of the atom X are each bonded to the first functional group, and the remaining 1 bonding site of the 4 bonding sites of the atom X is bonded to the second functional group, In (a1) and (b1), the raw material is supplied under the processing conditions in which the atom X is adsorbed on the surface of the substrate in a state where the first functional group is bonded to each of the 3 bonding sites of the atom X, The said n 1 is an integer of 1 or more, and the said n 2 is an integer of 1 or more.

24. A computer-readable recording medium that records a program which causes a substrate processing apparatus to perform steps (a) and (b) below to form an oxide film formed by laminating a first oxide film and a second oxide film on a substrate: (a) Forming the first oxide film containing atom X by performing the cycle including the following (a1) and (a2) n 1 times: (a1) Supplying a raw material having a partial structure in which a first functional group and a second functional group are directly bonded to the atom X, and the bond energy between the first functional group and the atom X is higher than the bond energy between the second functional group and the atom X to the substrate, and forming a first layer containing a component in which the first functional group is bonded to the atom X wherein, the first functional group contains an alkoxy group, and the second functional group contains at least any one of an amino group, an alkyl group, a halogenated group, a hydroxyl group, a hydrogen group, an aryl group, a vinyl group, and a nitro group; and (a2) supplying a first oxidizing agent to the substrate to oxidize the first layer and form a second layer containing the atom X and oxygen; and (b) Forming the second oxide film containing the atom X by performing the cycle including the following (b1) and (b2) n 2 times: (b1) A step of supplying the raw material to the substrate to form a third layer containing a component in which the first functional group is bonded to the atom X; and (b2) A step of supplying a second oxidant to the substrate under treatment conditions where the oxidizing power becomes higher than the oxidizing power when oxidizing the first layer in (a2), oxidizing the third layer, and forming a fourth layer containing the atom X and oxygen. wherein, said n 1 is an integer greater than or equal to 1, and said n 2 is an integer greater than or equal to 1.

25. A computer-readable recording medium that records a program which causes a substrate processing apparatus to perform steps (a) and (b) below to form an oxide film formed by laminating a first oxide film and a second oxide film on a substrate: (a) Forming the first oxide film containing atom X by performing the cycle including the following (a1) and (a2) n 1 times: (a1) Supplying a raw material having a partial structure in which a first functional group and a second functional group are directly bonded to the atom X, and the bond energy between the first functional group and the atom X is higher than the bond energy between the second functional group and the atom X to the substrate, and forming a first layer containing a component in which the first functional group is bonded to the atom X; and (a2) Supplying a first oxidant to the substrate to oxidize the first layer and form a second layer containing the atom X and oxygen; and (b) Forming the second oxide film containing the atom X by performing the cycle including the following (b1) and (b2) n 2 times: (b1) A step of supplying the raw material to the substrate to form a third layer containing a component in which the first functional group is bonded to the atom X; and (b2) A step of supplying a second oxidant to the substrate under treatment conditions where the oxidizing power is higher than the oxidizing power when oxidizing the first layer in (a2) to oxidize the third layer and form a fourth layer containing the atom X and oxygen. wherein, the atom X has four bonding sites, three of the four bonding sites of the atom X are each bonded to the first functional group, and the remaining one of the four bonding sites of the atom X is bonded to the second functional group, in (a1) and (b1), the raw material is supplied under the processing conditions in which the atom X is adsorbed on the surface of the substrate in a state where the first functional group is bonded to each of the three bonding sites of the atom X The said n 1 is an integer greater than or equal to 1, and the said n 2 is an integer greater than or equal to 1.

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