Semiconductor device manufacturing method, substrate processing device and recording medium

Abstract

The present invention relates to a method for manufacturing a semiconductor device, a substrate processing device and a recording medium. The subject is to improve the selectivity in selective growth while suppressing damage to the surface of the substrate. The method for manufacturing a semiconductor device has the following steps: (a) a process gas is supplied to a substrate having a first substrate not containing oxygen, a second substrate containing oxygen and a third substrate not containing oxygen and nitrogen exposed on the surface, and a protective film is formed on the surface of the third substrate; (b) a fluorine-containing gas is supplied to the substrate after the protective film is formed on the surface of the third substrate to modify the surface of the second substrate in a fluorine-terminated manner; and (c) a film-forming gas is supplied to the substrate after the surface of the second substrate is modified, and a film is selectively formed on the surface of the first substrate.

Description

Technical Field

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

[0002] As one of the steps in the manufacturing process of a semiconductor device, there is a case where a process is performed to selectively grow and form a film on the surface of a specific substrate among multiple substrates exposed on the surface of a substrate (hereinafter, this process is also referred to as selective growth or selective film formation) (for example, see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2013-243193 Summary of the invention

[0006] Problems to be solved by the invention

[0007] An object of the present invention is to provide a technology capable of improving the selectivity in the above-mentioned selective growth while suppressing damage to the surface of the substrate.

[0008] Means for solving problems

[0009] According to one embodiment of the present invention, a technique for performing the following steps is provided:

[0010] (a) supplying a processing gas to a substrate having a first base not containing oxygen, a second base containing oxygen, and a third base not containing oxygen and nitrogen exposed on the surface thereof to form a protective film on the surface of the third base;

[0011] (b) supplying a fluorine-containing gas to the substrate after forming the protective film on the surface of the third substrate to modify the surface of the second substrate in a fluorine-terminated manner; and

[0012] (c) A step of supplying a film forming gas to the substrate after the surface of the second base is modified to selectively form a film on the surface of the first base.

[0013] Effects of the Invention

[0014] According to the present invention, it is possible to improve the selectivity in the above-mentioned selective growth while suppressing damage to the surface of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of a vertical processing furnace of a substrate processing apparatus preferably used in one embodiment of the present invention, and shows a processing furnace 202 portion in a vertical cross-sectional view.

[0016] Figure 2 This is a schematic diagram of a vertical processing furnace of a substrate processing device preferably used in one embodiment of the present invention. Figure 1 A cross-sectional view taken along line AA shows a portion of the processing furnace 202 .

[0017] Figure 3 1 is a schematic diagram of the configuration of a controller 121 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 the form of a block diagram.

[0018] Figure 4 This is a diagram showing the processing sequence in the selective growth according to one embodiment of the present invention.

[0019] Figure 5 (a) is a partially enlarged cross-sectional view of the surface of the wafer 200 before cleaning; Figure 5 (b) is a partially enlarged cross-sectional view of the surface of the wafer 200 after cleaning treatment, in which a substrate 200a including a silicon nitride film, a substrate 200b including a silicon oxide film, and a substrate 200c including silicon are exposed on the surface; Figure 5 (c) is a partially enlarged cross-sectional view of the surface of the wafer 200 after a protective film 200e is formed on the surface of the substrate 200c by supplying an oxygen-containing gas; Figure 5 (d) is a partially enlarged cross-sectional view of the surface of the wafer 200 after the aminosilane-based gas is supplied to selectively adsorb silicon on the surfaces of the substrate 200b and the protective film 200e; Figure 5 (e) is a partially enlarged cross-sectional view of the surface of the wafer 200 after the surface of the substrate 200b and the protective film 200e to which silicon is adsorbed is selectively modified by supplying a fluorine-containing gas; Figure 5 (f) is a partially enlarged cross-sectional view of the surface of the wafer 200 after a silicon nitride film is selectively formed on the surface of the substrate 200a; Figure 5 (g) is to Figure 5 (f) is a partially enlarged cross-sectional view of the surface of the wafer 200 after the wafer 200 is exposed to the atmosphere. DETAILED DESCRIPTION

[0020] <One aspect of the present invention>

[0021] The following mainly refers to Figure 1 to Figure 4 An embodiment of the present invention will be described.

[0022] (1) Configuration of substrate processing apparatus

[0023] like Figure 1As shown, the processing furnace 202 has a heater 207 as a heating mechanism (temperature adjustment unit). The heater 207 is cylindrical and is vertically mounted by being supported by a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) the gas using heat.

[0024] On the inner side of the heater 207, a reaction tube 203 is arranged concentrically with the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC), and is formed into a cylindrical shape 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 into a cylindrical shape with an upper end and a lower end open. The upper end of the manifold 209 is engaged with the lower end of the reaction tube 203, and is configured in a manner to 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 installed vertically 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. The processing chamber 201 is formed in the hollow portion of the cylinder of the processing container. The processing chamber 201 is configured to accommodate a wafer 200 as a substrate. The wafer 200 is processed in the processing chamber 201 .

[0025] In the processing chamber 201, nozzles 249a to 249c as the first to third supply parts are respectively provided in a manner penetrating the side wall of the manifold 209. The nozzles 249a to 249c are also referred to as the first to third nozzles, respectively. The nozzles 249a to 249c are made of a heat-resistant material such as quartz or SiC. The nozzles 249a to 249c are connected to the gas supply pipes 232a to 232c, respectively. The nozzles 249a to 249c are different nozzles, and the nozzles 249a and 249c are respectively arranged adjacent to the nozzle 249b.

[0026] Mass flow controllers (MFCs) 241a to 241c as flow controllers (flow control units) and valves 243a to 243c as on-off valves are provided in order from the upstream side of the gas supply pipes 232a to 232c, respectively. Gas supply pipes 232d to 232h are connected to the downstream side of the gas supply pipes 232a to 232c compared to the valves 243a to 243c, respectively. MFCs 241d to 241h and valves 243d to 243h are provided in order from the upstream side of the gas supply pipes 232d to 232h, respectively. The gas supply pipes 232a to 232h are made of a metal material such as SUS, for example.

[0027] like Figure 2As shown in FIG. 1 , the nozzles 249a to 249c are respectively arranged in a circular ring-shaped space between the inner wall of the reaction tube 203 and the wafer 200 in a plan view, so as to stand up from the bottom to the top along the inner wall of the reaction tube 203 toward the arrangement direction of the wafer 200. That is, the nozzles 249a to 249c are respectively arranged along the wafer arrangement area in the area which is on the side of the wafer arrangement area where the wafers 200 are arranged and horizontally surrounds the wafer arrangement area. When viewed from above, the nozzle 249b is arranged so as to face the exhaust port 231a described later on a straight line with the center of the wafer 200 carried into the processing chamber 201 sandwiched therebetween. The nozzles 249a and 249c are arranged so as to sandwich a straight line L (which passes through the center of the nozzle 249b and the exhaust port 231a) from both sides along the inner wall of the reaction tube 203 (the outer periphery of the wafer 200). The straight line L is also a straight line passing through the nozzle 249b and the center of the wafer 200. That is, the nozzle 249c can also be arranged on the opposite side of the nozzle 249a with the straight line L sandwiched therebetween. The nozzles 249a and 249c are arranged line-symmetrically with the straight line L as the axis of symmetry. Gas supply holes 250a to 250c for supplying gas are respectively provided on the side surfaces of the nozzles 249a to 249c. The gas supply holes 250a to 250c are respectively opened in a manner opposite to (facing) the exhaust port 231a when viewed from above, and are configured to be able to supply gas toward the wafer 200. A plurality of gas supply holes 250a to 250c are provided from the lower part to the upper part of the reaction tube 203.

[0028] A gas containing halogen and silicon (Si) as the main element constituting the film formed on the wafer 200, i.e., a halogenated silane gas, is supplied from the gas supply pipe 232a via the MFC 241a, the valve 243a, and the nozzle 249a into the processing chamber 201. The halogenated silane gas functions as a film-forming gas, i.e., a Si source (raw material gas). Halogen elements include chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc. As the halogenated silane gas, for example, a chlorosilane gas containing Si and Cl can be used, for example, silicon tetrachloride (SiCl4) gas can be used.

[0029] A fluorine (F)-containing gas is supplied from the gas supply pipe 232b via the MFC 241b, the valve 243b, and the nozzle 249b into the processing chamber 201. As the fluorine-containing gas, for example, fluorine (F2) gas can be used.

[0030] A hydrogen nitride gas as a nitrogen (N)-containing gas is supplied from the gas supply pipe 232c via the MFC 241c, the valve 243c, and the nozzle 249c into the processing chamber 201. The hydrogen nitride gas functions as a film-forming gas, i.e., an N source (nitriding gas, nitriding agent). As the hydrogen nitride gas, for example, ammonia (NH 3 ) gas can be used.

[0031] An aminosilane-based gas, which is a gas containing Si and an amino group, is supplied into the processing chamber 201 from the gas supply pipe 232g via the MFC 241g, the valve 243g, the gas supply pipe 232c, and the nozzle 249c.

[0032] As an aminosilane-based gas, for example, a monoaminosilane (SiH3R) gas, which is a raw material containing one amino group in the composition formula (in one molecule), can be used. Here, R represents an amino group in which one N atom is coordinated with one or two hydrocarbon groups containing one or more C atoms (a substance in which one or both of the H of the amino group represented by NH2 are replaced with hydrocarbon groups containing one or more C atoms). In the case where one N is coordinated with two hydrocarbon groups constituting a part of the amino group, the two hydrocarbon groups may be the same hydrocarbon group or different hydrocarbon groups. In addition, the hydrocarbon group may also contain unsaturated bonds such as double bonds and triple bonds. In addition, the amino group may also have a cyclic structure. Since the amino group is bonded to Si, the central atom of the SiH3R molecule, the amino group is also referred to as a ligand or an amino ligand.

[0033] As SiH3R gas, for example, ethylmethylaminosilane (SiH3[N(CH3)(C2H5)]) gas, dimethylaminosilane (SiH3[N(CH3)2]) gas, diisopropylaminosilane (SiH3[N(C3H7)2]) gas, di-sec-butylaminosilane (SiH3[H(C4H9)2]) gas, dimethylpiperidinylsilane (SiH3[NC5H8(CH3)2]) gas, and diethylpiperidinylsilane (SiH3[NC5H8(C2H5)2]) gas can be used.

[0034] Oxygen (O)-containing gas is supplied from the gas supply pipe 232h via the MFC 241h, the valve 243h, the gas supply pipe 232a, and the nozzle 249a into the processing chamber 201. The O-containing gas functions as a processing gas, that is, as an oxidant. As the O-containing gas, for example, oxygen (O2) gas can be used.

[0035] As an inert gas, nitrogen (N2) gas is supplied from gas supply pipes 232d to 232f via MFCs 241d to 241f, valves 243d to 243f, gas supply pipes 232a to 232c, and nozzles 249a to 249c into the processing chamber 201. N2 gas functions as a purge gas, carrier gas, dilution gas, and the like.

[0036] The film forming gas supply system (raw material gas supply system, reaction gas supply system) is mainly composed of gas supply pipes 232a, 232c, MFC241a, 241c, valves 243a, 243c. The processing gas supply system (oxygen-containing gas supply system) is mainly composed of gas supply pipe 232h, MFC241h, and valve 243h. The aminosilane gas supply system is mainly composed of gas supply pipe 232g, MFC241g, and valve 243g. The fluorine-containing gas supply system is mainly composed of gas supply pipe 232b, MFC241b, and valve 243b. The inactive gas supply system is mainly composed of gas supply pipes 232d~232f, MFC241d~241f, and valves 243d~243f.

[0037] Any or all of the above-mentioned various supply systems may also be configured as an integrated supply system 248 in which valves 243a to 243h, MFCs 241a to 241h, etc. are integrated. The integrated supply system 248 is configured to be connected to the gas supply pipes 232a to 232h, respectively, and the supply action of various gases into the gas supply pipes 232a to 232h, i.e., the opening and closing action of the valves 243a to 243h, the flow rate adjustment action performed by the MFCs 241a to 241h, etc., is controlled by the controller 121 described later. The integrated supply system 248 is configured as an integrated or split integrated unit, and is configured to be detachable relative to the gas supply pipes 232a to 232h, etc., as an integrated unit unit, and the integrated supply system 248 can be maintained, replaced, and added as an integrated unit unit.

[0038] An exhaust port 231a is provided below the side wall of the reaction tube 203 to exhaust the atmosphere in the processing chamber 201. Figure 2As shown, the exhaust port 231a is arranged at a position opposite (facing) to the nozzles 249a to 249c (gas supply holes 250a to 250c) sandwiching the wafer 200 when viewed from above. The exhaust port 231a can also be arranged along the side wall of the reaction tube 203 from the bottom to the top along the wafer arrangement area. The exhaust port 231a is connected to the exhaust pipe 231. 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) that detects the pressure in the processing chamber 201 and an APC (Auto Pressure Controller: automatic pressure controller) valve 244 as a pressure regulator (pressure regulating unit). The APC valve 244 is configured to open and close the valve when the vacuum pump 246 is in operation, so that vacuum exhaust in the processing chamber 201 can be performed and vacuum exhaust can be stopped. In addition, the valve opening is adjusted based on pressure information detected by the pressure sensor 245 when the vacuum pump 246 is in operation, so that the pressure in the processing chamber 201 can be adjusted. The exhaust system is mainly composed of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. It is also conceivable that the vacuum pump 246 is included in the exhaust system.

[0039] A sealing cover 219 is provided below the manifold 209 as a furnace cover body that can airtightly close the lower end opening of the manifold 209. The sealing cover 219 is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220b is provided on the upper surface of the sealing cover 219 as a sealing member that abuts against the lower end of the manifold 209.

[0040] A rotating mechanism 267 is provided below the sealing cover 219 to rotate the wafer boat 217 described later. The rotating shaft 255 of the rotating mechanism 267 is made of a metal material such as SUS, and penetrates the sealing cover 219 to be connected to the wafer boat 217. The rotating mechanism 267 is configured to rotate the wafer 200 by rotating the wafer boat 217. The sealing cover 219 is configured to be raised and lowered in the vertical direction by a wafer boat elevator 115 as an elevating mechanism provided outside the reaction tube 203. The wafer boat elevator 115 is configured as a transport device (transport mechanism) that moves the wafer 200 into and out of the processing chamber 201 (transport) by raising and lowering the sealing cover 219.

[0041] A gate plate 219s is provided below the manifold 209 as a furnace cover, which can hermetically seal the lower end opening of the manifold 209 when the sealing cover 219 is lowered and the wafer boat 217 is moved out of the processing chamber 201. The gate plate 219s is made of a metal material such as SUS and is formed into a disc shape. An O-ring 220c is provided on the upper surface of the gate plate 219s as a sealing member that abuts against the lower end of the manifold 209. The opening and closing action (lifting action, rotation action, etc.) of the gate plate 219s is controlled by the gate plate opening and closing mechanism 115s.

[0042] The wafer boat 217 as a substrate support is configured to support multiple wafers 200, for example, 25 to 200 wafers, in a horizontal posture and arranged in a vertical direction with their centers aligned with each other, and arranged in multiple layers, that is, arranged at intervals. The wafer boat 217 is made of a heat-resistant material such as quartz or SiC. A heat shield 218 made of a heat-resistant material such as quartz or SiC is supported in multiple layers at the bottom of the wafer boat 217.

[0043] A temperature sensor 263 as a temperature detector is provided in the reaction tube 203. The power supply to the heater 207 is adjusted based on the temperature information detected by the temperature sensor 263 so that the temperature in the processing chamber 201 becomes a desired temperature distribution. The temperature sensor 263 is provided along the inner wall of the reaction tube 203.

[0044] like Figure 3 As shown, the controller 121 as a control unit (control unit) is configured as a computer having a CPU (Central Processing Unit; central processing unit) 121a, a RAM (Random Access Memory; 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 so as to be able to exchange data with the CPU 121a via an internal bus 121e. The controller 121 is connected to an input / output device 122 configured as, for example, a touch panel.

[0045] The storage device 121c is composed of, for example, a flash memory, an HDD (Hard Disk Drive), etc. A control program for controlling the operation of the substrate processing device, a process recipe recording the steps and conditions of the substrate processing described later, etc. are stored in a readable manner in the storage device 121c. The process recipe is a combination of the controller 121 to perform the steps in the substrate processing described later and to obtain a specified result, and functions as a program. Hereinafter, the process recipe, the control program, etc. are also simply referred to as a program. In addition, the process recipe is also referred to as a recipe. When the word "program" is used in this specification, there are cases that only the recipe is included, only the control program is included, or both of the above are included. RAM121b is configured as a storage area (working area) for temporarily storing programs, data, etc. read by CPU121a.

[0046] The I / O port 121d is connected to the above-mentioned MFCs 241a to 241h, valves 243a to 243h, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotation mechanism 267, boat elevator 115, shutter opening and closing mechanism 115s, etc.

[0047] The CPU 121a is configured to read the control program from the storage device 121c and execute it, and to read the recipe from the storage device 121c in response to the input of the operation command from the input / output device 122. The CPU 121a is configured to control the flow rate adjustment operation of various gases by the MFCs 241a to 241h, the opening and closing operation of the valves 243a to 243h, the opening and closing operation of the APC valve 244 and the pressure adjustment operation by the APC valve 244 based on the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment operation of the heater 207 by the temperature sensor 263, the rotation and rotation speed adjustment operation of the wafer boat 217 by the rotation mechanism 267, the lifting and lowering operation of the wafer boat 217 by the wafer boat elevator 115, the opening and closing operation of the shutter 219s by the shutter opening and closing mechanism 115s, etc. according to the contents of the read recipe.

[0048] The controller 121 can be configured by installing the above-mentioned program stored in the external storage device 123 on a computer. The external storage device 123 includes, for example, a disk such as an HDD, an optical disk such as a CD, an optical disk such as an MO, a semiconductor memory such as a USB memory, etc. The storage device 121c and the external storage device 123 are configured as a recording medium that can be read by a computer. Hereinafter, they are also simply collectively referred to as recording media. When the term recording medium is used in this specification, there is a case where only the storage device 121c is included, a case where only the external storage device 123 is included, or a case where both of the above are included. It should be noted that the provision of the program to the computer can also be carried out without using the external storage device 123 and using communication means such as the Internet and dedicated lines.

[0049] (2) Substrate processing step

[0050] Main Use Figure 4 , Figure 5 (a)~ Figure 5 (g) describes the following selective growth (selective film formation) processing sequence example, that is, using the above-mentioned substrate processing apparatus, as a process of the manufacturing process of the semiconductor device, a film is selectively grown on the surface of a specific substrate among a variety of substrates exposed on the surface of the wafer 200 as a substrate to form a film. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

[0051] exist Figure 4 The following steps are performed in the processing sequence shown:

[0052] Step A, supplying O2 gas as a processing gas to a wafer 200 having a first substrate (substrate 200a) containing no O and including a silicon nitride film (SiN film), a second substrate (substrate 200b) containing O and including a silicon oxide film (SiO film), and a third substrate (substrate 200c) containing no O and N and including single crystal silicon (Si) on the surface thereof, and forming a SiO film as a protective film 200e on the surface of the substrate 200c;

[0053] Step B, supplying SiH3R gas as aminosilane-based gas to the wafer 200 after the protective film 200e is formed on the surface of the substrate 200c, and allowing Si contained in the SiH3R gas to be adsorbed on the surfaces of the substrate 200b and the protective film 200e;

[0054] Step C, supplying F2 gas as fluorine-containing gas to the wafer 200 after Si is adsorbed on the surfaces of the substrate 200b and the protective film 200e, so that Si adsorbed on the surfaces of the substrate 200b and the protective film 200e reacts with the F2 gas, thereby modifying the surfaces of the substrate 200b and the protective film 200e; and

[0055] In step D, SiCl 4 gas and NH 3 gas are supplied as film forming gases to the wafer 200 after the surfaces of the substrate 200 b and the protective film 200 e are modified, and a SiN film as a film containing Si and N is selectively formed on the surface of the substrate 200 a.

[0056] It should be noted that Figure 4 An example is shown in which a cycle of performing the following steps non-simultaneously for a specified number of times (n times, n is an integer greater than 1) in step D is performed, wherein the steps are: step D1 of supplying SiCl4 gas to the chip 200 and step D2 of supplying NH3 gas to the chip 200.

[0057] In this specification, for convenience, there is also an example in which the above-mentioned processing sequence is shown as follows. The same expression is also used in the following description of other schemes, etc.

[0058]

[0059] When the term "wafer" is used in this specification, it may refer to the wafer itself or a laminate of a wafer and a predetermined layer or film formed on its surface. When the term "surface of a wafer" is used in this specification, it may refer to the surface of the wafer itself or the surface of a predetermined layer, etc. formed on the wafer. When the term "a predetermined layer is formed on a wafer" is written in this specification, it may refer to directly forming a predetermined layer on the surface of the wafer itself or forming a predetermined layer on a layer, etc. formed on the wafer. When the term "substrate" is used in this specification, it has the same meaning as when the term "wafer" is used.

[0060] (Wafer filling and wafer boat loading)

[0061] After the plurality of wafers 200 are loaded into the wafer boat 217 (wafer filling), the shutter 219s is moved by the shutter opening and closing mechanism 115s to open the lower end opening of the manifold 209 (shutter opening). Figure 1 As shown, the boat 217 supporting the plurality of wafers 200 is lifted by the boat elevator 115 and carried into the processing chamber 201 (boat loading). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0062] like Figure 5As shown in (a), the following state is achieved, i.e., a plurality of substrates are exposed in advance on the surface of the chip 200, and here, as an example, the plurality of substrates are a substrate 200a including a SiN film (a nitride film as a non-O-containing film, i.e., a non-oxide film), a substrate 200b including a SiO film (as an O-containing film, i.e., an oxide film), and a substrate 200c including a single crystal Si (as a non-O and N-containing substance). That is, here, an example is shown in which the substrate 200a is composed of a SiN film as an insulating substance (insulator), the substrate 200b is composed of a SiO film as an insulating substance (insulator), and the substrate 200c is composed of a single crystal Si as a semiconductor substance. It should be noted that, as Figure 5 As shown in (a), when a natural oxide film 200d is formed on the surface of the wafer 200, the wafer 200 is cleaned (DHF cleaning) using, for example, a diluted hydrofluoric acid (DHF) aqueous solution, i.e., a hydrogen fluoride (HF) aqueous solution, in advance, i.e., before loading the wafer boat, to remove the natural oxide film 200d formed on the surface of the wafer 200 (natural oxide film removal). Specifically, the wafer 200 is cleaned with DHF, such as Figure 5 As shown in (b), the natural oxide film 200d formed on the surface of the substrate 200a is removed, and the material of the substrate 200a, that is, the SiN film, is exposed on the outermost surface of the substrate 200a. As a result, the surface of the substrate 200a can be uniformly processed in the step D described later. When the natural oxide film 200d formed on the surface of the substrate 200a is removed, the natural oxide film 200d formed on the surface of the substrate 200c exposed on the surface of the wafer 200 is also removed, and the material of the substrate 200c, that is, the single crystal Si, is also exposed on the outermost surface of the substrate 200c. As a result, the surface of the substrate 200c can be uniformly processed in the step A described later.

[0063] (Pressure regulation and temperature regulation)

[0064] The vacuum pump 246 performs vacuum exhaust (decompression exhaust) so that the space in the processing chamber 201, i.e., the space where the wafer 200 is located, becomes the desired pressure (vacuum degree). At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback-controlled based on the measured pressure information. In addition, the heater 207 heats the wafer 200 in the processing chamber 201 so that the desired processing temperature is reached. At this time, the power-on state of the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the temperature distribution in the processing chamber 201 becomes the desired temperature distribution. In addition, the rotation of the wafer 200 by the rotation mechanism 267 is started. The exhaust in the processing chamber 201, the heating and rotation of the wafer 200 are all continued at least until the processing of the wafer 200 is completed.

[0065] (Select Growth)

[0066] Then, the following steps A to D are performed in sequence.

[0067] [Step A]

[0068] In this step, a wafer 200 in a processing chamber 201, i.e., Figure 5 As shown in (b), O2 gas is supplied to the wafer 200 having the substrate 200a, the substrate 200b, and the substrate 200c exposed on the surface.

[0069] Specifically, valve 243h is opened to allow O2 gas to flow into gas supply pipe 232h. O2 gas is flow-regulated by MFC 241h, supplied into processing chamber 201 via gas supply pipe 232a and nozzle 249a, and exhausted from exhaust port 231a. At this time, O2 gas is supplied to wafer 200 (O2 gas supply). At this time, valves 243e and 243f are opened to supply N2 gas into processing chamber 201 via nozzles 249b and 249c, respectively. The supply of N2 gas may not be implemented.

[0070] The treatment conditions in this step may include:

[0071] O2 gas supply flow rate: 10-10000sccm, preferably 100-10000sccm

[0072] O2 gas supply time: 1 to 180 minutes, preferably 1 to 60 minutes

[0073] N2 gas supply flow rate (each gas supply pipe): 0 to 10000 sccm, preferably 100 to 10000 sccm

[0074] Treatment temperature: room temperature (25°C) to 600°C, preferably 50 to 550°C

[0075] Treatment pressure: 1 to atmospheric pressure (101325 Pa), preferably 10 to 5000 Pa, more preferably 100 to 1000 Pa.

[0076] The conditions described here are conditions in which the surface of the substrate 200a is not oxidized but the surface of the substrate 200c is oxidized.

[0077] It should be noted that the expression of a numerical range such as "1 to 101325 Pa" in this specification indicates that the lower limit and the upper limit are included in the range. Therefore, for example, "1 to 101325 Pa" means "1 Pa or more and 101325 Pa or less". The same applies to other numerical ranges.

[0078] By supplying O2 gas to the wafer 200 under the above conditions, Figure 5As shown in (c), it is possible to selectively (preferentially) oxidize the surface of the substrate 200c while suppressing the oxidation of the surface of the substrate 200a. The surface of the substrate 200c is oxidized, so that a SiO film is formed on the surface of the substrate 200c as a protective film 200e. At this time, the substrate 200b is composed of a SiO film, so the surface of the substrate 200b is not oxidized, and a protective film 200e is not newly formed on its surface. The reason why such selective (preferential) oxidation can be achieved is that the processing conditions in this step are set to the conditions under which the surface of the substrate 200a is not oxidized, that is, the conditions under which an oxide film (SiO film or SiON film) is not formed on the surface of the substrate 200a. In this step, by performing dry oxidation under the condition that the surface of the substrate 200a is not oxidized, it is possible to selectively oxidize only the surface of the substrate 200c, that is, selectively form a SiO film as a protective film 200e only on the surface of the substrate 200c. In this step, the surface of the substrate 200c is oxidized under a pressure condition lower than atmospheric pressure (vacuum atmosphere, reduced pressure atmosphere), thereby improving the film thickness controllability and film thickness uniformity of the protective film 200e formed on the surface of the substrate 200c.

[0079] The protective film 200e formed on the surface of the substrate 200c functions as a film for protecting the substrate 200c when the F2 gas is supplied in the later-described step C. In the later-described step C, when the F2 gas contacts the surface of the substrate 200c, there is a case where the surface of the substrate 200c is etched and damaged by etching. By forming the protective film 200e on the surface of the substrate 200c, the F2 gas can be prevented from contacting the surface of the substrate 200c in step C, thereby suppressing the etching of the surface of the substrate 200c and suppressing the etching damage to the surface of the substrate 200c. It should be noted that the protective film 200e will not have an adverse effect on the various processes in steps B and C.

[0080] The thickness of the protective film 200e formed in this step is The film thickness is about 1000 mm / s, which is thinner than the film thickness of the natural oxide film 200d formed on the surface of the substrate 200c before DHF cleaning. Even if the film thickness of the protective film 200e is thin, the uniformity of the film thickness of the protective film 200e is much higher than that of the natural oxide film, so that the contact between the F2 gas and the surface of the substrate 200c during the supply of the F2 gas in step C described later can be fully suppressed.

[0081] After the protective film 200e is formed on the surface of the substrate 200c, the valve 243h is closed to stop supplying the O2 gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove the residual gas and the like in the processing chamber 201 from the processing chamber 201. At this time, the valves 243d to 243f are opened to supply the N2 gas into the processing chamber 201 through the nozzles 249a to 249c. The N2 gas supplied from the nozzles 249a to 249c functions as a purge gas, thereby purging the processing chamber 201.

[0082] As O-containing gases, in addition to O2 gas, O-containing gases such as nitrous oxide (N2O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, ozone (O3) gas, water vapor (H2O gas), carbon monoxide (CO) gas, and carbon dioxide (CO2) gas can be used.

[0083] As the inert gas, in addition to N 2 gas, a rare gas such as Ar gas, He gas, Ne gas, or Xe gas can be used. This also applies to each step described later.

[0084] [Step B]

[0085] After step A is completed, SiH 3 R gas is supplied to the wafer 200 in the processing chamber 201 , that is, the wafer 200 after the protective film 200 e is formed on the surface of the substrate 200 c .

[0086] Specifically, valve 243g is opened to allow SiH3R gas to flow into gas supply pipe 232g. SiH3R gas is flow-regulated by MFC241g, supplied into processing chamber 201 via gas supply pipe 232c and nozzle 249c, and exhausted from exhaust port 231a. At this time, SiH3R gas is supplied to wafer 200 (SiH3R gas supply). At this time, valves 243d and 243e are opened, and N2 gas is supplied into processing chamber 201 via nozzles 249a and 249b, respectively. The supply of N2 gas may not be implemented.

[0087] The treatment conditions in this step may include:

[0088] SiH3R gas supply flow rate: 1-2000sccm, preferably 1-500sccm

[0089] SiH3R gas supply time: 1 second to 60 minutes

[0090] N2 gas supply flow rate (each gas supply pipe): 0~10000sccm

[0091] Processing temperature: room temperature (25°C) ~ 600°C, preferably room temperature ~ 450°C

[0092] Processing pressure: 1-2000Pa, preferably 1-1000Pa.

[0093] The conditions described here are conditions under which the SiH3R gas in the processing chamber 201 does not undergo gas phase decomposition (thermal decomposition). It should be noted that the substrate 200b and the protective film 200e have surfaces terminated with hydroxyl groups (OH) in the entire region (entire surface). The substrate 200a has a surface that is not terminated with OH in many regions, that is, a surface that is terminated with OH in a portion of the region.

[0094] By supplying SiH3R gas to the wafer 200 under the above conditions, Figure 5 As shown in (d), it is possible to selectively (preferentially) adsorb Si contained in SiH3R gas on the surface of substrate 200b while suppressing the adsorption of Si contained in SiH3R gas on the surface of substrate 200a. At this time, Si contained in SiH3R gas can also be selectively (preferentially) adsorbed on the surface of protective film 200e. In addition, at this time, there is also a situation where Si contained in SiH3R gas is adsorbed on a part of the surface of substrate 200a, but the adsorption amount is less than the adsorption amount of Si on the surfaces of substrate 200b and protective film 200e respectively. The reason why such selective (preferential) adsorption can be achieved is that the processing conditions in this step are set to the conditions where SiH3R gas does not undergo gas phase decomposition in the processing chamber 201. In addition, it is also because the surfaces of substrate 200b and protective film 200e are each terminated with OH in the entire area, while many areas of the surface of substrate 200a are not terminated with OH (part of the surface area is terminated with OH). In this step, since the SiH3R gas does not undergo gas phase decomposition in the processing chamber 201, the Si contained in the SiH3R will not be deposited in multiple layers on the surfaces of the substrates 200a, 200b and the protective film 200e. In this step, on the surfaces of the substrate 200b and the protective film 200e, the OH termination formed in the entire area of ​​the surface reacts with the SiH3R, and the Si contained in the SiH3R is chemically adsorbed on the entire area of ​​the surface of the substrate 200b and the protective film 200e. In contrast, on the surface of the substrate 200a, since there is no OH termination in many areas of the surface, the Si contained in the SiH3R is not chemically adsorbed in these many areas. However, there is also the following situation: the OH termination formed in a part of the surface of the substrate 200a reacts with the SiH3R, and the Si contained in the SiH3R is chemically adsorbed in this part of the area. It should be noted that when the Si contained in the SiH3R is chemically adsorbed on the surface of the substrate, it will be chemically adsorbed in a state where H is bonded to Si.

[0095] It should be noted that if the supply of SiH3R gas is continued for a predetermined time, the chemical adsorption of Si on the surfaces of the substrate 200b and the protective film 200e is saturated. That is, the chemical adsorption of Si on the surfaces of the substrate 200b and the protective film 200e is self-limiting. In other words, if a layer of Si is formed on the surfaces of the substrate 200b and the protective film 200e, Si will not be further chemically adsorbed on the surfaces of the substrate 200b and the protective film 200e. As a result, the amount of Si adsorbed on the surfaces of the substrate 200b and the protective film 200e becomes a roughly uniform amount over the entire area of ​​the surfaces of the substrate 200b and the protective film 200e.

[0096] After Si is selectively adsorbed on the surfaces of the substrate 200b and the protective film 200e, the valve 243g is closed to stop the supply of SiH3R gas into the processing chamber 201. Then, the gas remaining in the processing chamber 201 is exhausted from the processing chamber 201 by the same processing steps as the purging in step A.

[0097] As aminosilane-based gas, in addition to the monoaminosilane gas containing only one amino group in one molecule, diaminosilane (SiH2RR') gas containing two amino groups in one molecule and triaminosilane (SiHRR'R") gas containing three amino groups in one molecule can be used.

[0098] In addition, as the aminosilane-based gas, an aminosilane compound represented by the following general formula [1] can be used.

[0099] SiA x [(NB2) (4-x) ] [1]

[0100] In formula [1], A represents a hydrogen atom, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, or an alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, or the like. The alkyl group may be not only a straight-chain alkyl group but also a branched alkyl group such as an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, or the like. The alkoxy group may be not only a straight-chain alkoxy group but also a branched alkoxy group such as an isopropoxy group, an isobutoxy group, or the like. B represents a hydrogen atom or an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, or the like. The alkyl group may be not only a straight-chain alkyl group but also a branched alkyl group such as an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, or the like. Multiple A's may be the same or different. Two B's may be the same or different. x is an integer of 1 to 3.

[0101] [Step C]

[0102] After step B is completed, F2 gas is supplied to the wafer 200 in the processing chamber 201, that is, the wafer 200 after Si is selectively adsorbed on the surfaces of the base 200b and the protective film 200e.

[0103] Specifically, valve 243b is opened to allow F2 gas to flow into gas supply pipe 232b. F2 gas is flow-regulated by MFC241b, supplied to processing chamber 201 via nozzle 249b, and exhausted from exhaust port 231a. At this time, F2 gas is supplied to wafer 200 (F2 gas supply). At this time, valves 243d and 243f are opened to supply N2 gas to processing chamber 201 via nozzles 249a and 249c, respectively. N2 gas supply may not be implemented.

[0104] The treatment conditions in this step may include:

[0105] F2 gas supply flow rate: 1 to 2000 sccm, preferably 1 to 500 sccm

[0106] F2 gas supply time: 1 second to 60 minutes

[0107] Treatment temperature: room temperature to 550°C, preferably room temperature to 450°C.

[0108] The other conditions are the same as those in step B. The conditions described here are conditions under which the surfaces of the substrate 200b and the protective film 200e are not etched, and conditions under which the surfaces of the substrate 200b and the protective film 200e are modified (F-terminated) as described later.

[0109] By supplying F2 gas to the wafer 200 under the above conditions, Si adsorbed on the surfaces of the substrate 200b and the protective film 200e can react with the F2 gas, so that the surfaces of the substrate 200b and the protective film 200e can be modified in a non-etching manner. At this time, the surface of the substrate 200c is protected by the protective film 200e, thereby preventing the F2 gas from contacting the surface of the substrate 200c, thereby avoiding etching damage to the surface of the substrate 200c. The modified substrate 200b and the protective film 200e become surfaces with F termination (SiF termination). It should be noted that, when focusing on the atoms present on the outermost surfaces of the modified substrate 200b and the protective film 200e, it can be said that the substrate 200b and the protective film 200e each have a surface with F termination. In addition, when focusing on the atoms present on the outermost surfaces of the modified substrate 200b and the protective film 200e and the atoms bonded to the atoms, it can be said that the substrate 200b and the protective film 200e each have a surface terminated by SiF. In this specification, for convenience, the former is mainly used. By making the surfaces of the substrate 200b and the protective film 200e each terminated by F, the film-forming reaction is no longer performed on the surfaces of the substrate 200b and the protective film 200e in the step D described later. To be precise, the time until the film-forming reaction occurs, i.e., the incubation time, can be prolonged. It should be noted that when there are organic components contained in SiH3R on the surfaces of the substrate 200b and the protective film 200e, when the Si adsorbed on the surfaces of the substrate 200b and the protective film 200e reacts with the F2 gas, the organic components are removed from the surfaces of the substrate 200b and the protective film 200e.

[0110] like Figure 5As shown in (e), in this step, the surface modification of the substrate 200a can be suppressed while the surface modification of the substrate 200a can be selectively (preferentially) modified. At this time, there is also a situation where a portion of the surface of the substrate 200a is modified, but the amount of the modification is a small amount compared to the amount of modification of the surfaces of the substrate 200b and the protective film 200e. The reason why such selective (preferential) modification can be achieved is that after the implementation of step B, many areas of the surface of the substrate 200a are not adsorbed with Si, while the entire area of ​​the surface of the substrate 200b and the protective film 200e are adsorbed with Si. Since Si is not adsorbed in many areas of the surface of the substrate 200a, the reaction between Si and F2 does not occur, and as a result, F end-capping will not be formed in these many areas. However, as described above, there is also a situation where Si is adsorbed in a part of the surface of the substrate 200a, in which case F end-capping will also be formed in this part of the area. On the other hand, on the surfaces of the substrate 200b and the protective film 200e, Si adsorbed on the surface reacts with F2 in the entire area of ​​these surfaces to generate F-containing free radicals, and under the action of the free radicals, very stable F-terminated (SiF-terminated) is formed in the entire area of ​​these surfaces. Examples of F-containing free radicals include F, SiF, SiF2, SiF3, SiHF, SiH2F, SiHF2, etc.

[0111] It should be noted that, as described above, the amount of Si adsorbed on the substrate 200b and the protective film 200e in step B becomes a substantially uniform amount over the entire area of ​​the surface of each of the substrate 200b and the protective film 200e. Therefore, in this step, the amount of F-containing radicals generated on the surface of each of the substrate 200b and the protective film 200e becomes a substantially uniform amount over the entire area within the surface. As a result, the modification of each of the substrate 200b and the protective film 200e is substantially uniform over the entire area of ​​these surfaces.

[0112] In addition, in many areas of the surface of the substrate 200a, since Si is not adsorbed as described above, the reaction between Si and F2 does not occur, and no F-containing free radicals are generated, and these many areas will not be modified. However, in the case where Si is adsorbed in a part of the surface of the substrate 200a, Si reacts with F2 in this part to generate F-containing free radicals, and there is also a case where this part is modified, as described above. As a result, the surface of the substrate 200a is basically not damaged by etching, and adsorption sites are maintained in many areas of its surface.

[0113] After the surfaces of the substrate 200a, 200b and the protective film 200e are selectively modified, the valve 243b is closed to stop the supply of F2 gas into the processing chamber 201. Then, the gas remaining in the processing chamber 201 is exhausted from the processing chamber 201 by the same processing steps as the purging in step A.

[0114] As fluorine-containing gases, in addition to F2 gas, chlorine trifluoride (ClF3) gas, chlorine fluoride (ClF) gas, F2+nitrogen oxide (NO) gas, ClF+NO gas, nitrogen trifluoride (NF3) gas, tungsten hexafluoride (WF6) gas, nitrosyl fluoride (FNO) gas or a mixed gas of these gases can be used.

[0115] [Step D]

[0116] After step C is completed, SiCl4 gas and NH3 gas are supplied to the wafer 200 in the processing chamber 201, that is, the wafer 200 after the surfaces of the base 200b and the protective film 200e have been modified. In this step, steps D1 and D2 are performed in sequence.

[0117] [Step D1]

[0118] In this step, SiCl 4 gas is supplied to the wafer 200 in the processing chamber 201 after the surfaces of the substrate 200 b and the protective film 200 e among the substrates 200 a and 200 b and the protective film 200 e are selectively modified.

[0119] Specifically, valve 243a is opened to allow SiCl4 gas to flow into gas supply pipe 232a. SiCl4 gas is flow-regulated by MFC241a, supplied to processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, SiCl4 gas is supplied to wafer 200 (SiCl4 gas supply). At this time, valves 243e and 243f may also be opened to supply N2 gas to processing chamber 201 via nozzles 249b and 249c, respectively.

[0120] The treatment conditions in this step may include:

[0121] SiCl4 gas supply flow rate: 1 to 2000 sccm, preferably 10 to 1000 sccm

[0122] SiCl4 gas supply time: 1 to 180 seconds, preferably 10 to 120 seconds

[0123] Treatment temperature: 350-600°C, preferably 400-550°C

[0124] Treatment pressure: 1-2000Pa, preferably 10-1333Pa.

[0125] The other processing conditions are the same as those in step B.

[0126] By supplying SiCl4 gas to the wafer 200 under the above conditions, a Si-containing layer containing Cl is formed on the surface of the substrate 200a including the unmodified region in the substrates 200a, 200b and the protective film 200e. That is, the Si-containing layer containing Cl is formed starting from the unmodified region in the substrate 200a, i.e., the region where the adsorption site is maintained. The Si-containing layer containing Cl is obtained by physical adsorption, chemical adsorption, and partial decomposition of SiCl4 on the surface of the substrate 200a (SiCl x ) chemical adsorption, Si accumulation caused by thermal decomposition of SiCl4, etc. The Si-containing layer containing Cl can be SiCl4, SiCl x The adsorption layer (physical adsorption layer, chemical adsorption layer) of Cl may also be a deposition layer of Si containing Cl. In this specification, the Si-containing layer containing Cl is also referred to as the Si-containing layer.

[0127] In this step, while suppressing the formation of Si-containing layers on the surfaces of the substrate 200b and the protective film 200e, a Si-containing layer can be selectively formed on the surface of the substrate 200a. It should be noted that, when the modification of the surfaces of the substrate 200b and the protective film 200e is insufficient due to some reason, there is a case where a very small amount of Si-containing layer is formed on the surfaces of the substrate 200b and the protective film 200e, but even in this case, the thickness of the Si-containing layer formed on the surfaces of the substrate 200b and the protective film 200e is much thinner than the thickness of the Si-containing layer formed on the surface of the substrate 200a. The selective formation of such a Si-containing layer can be achieved because the F end capping present on the surfaces of the substrate 200b and the protective film 200e is the main reason for hindering the formation of the Si-containing layer (Si adsorption) on the surfaces of the substrate 200b and the protective film 200e, that is, it functions as an inhibitor. It should be noted that the F-terminated regions existing on the surfaces of the base 200 b and the protective film 200 e do not disappear during the present step and are stably maintained.

[0128] After the Si-containing layer is formed on the surface of the substrate 200a, the valve 243a is closed to stop the supply of SiCl4 gas into the processing chamber 201. Then, the gas remaining in the processing chamber 201 is removed (purged) from the processing chamber 201 by the same processing steps as the purging in step A.

[0129] As raw material gases (film-forming gases), in addition to SiCl4 gas, chlorosilane gases such as monochlorosilane (SiH3Cl, abbreviated as: MCS) gas, dichlorosilane (SiH2Cl2, abbreviated as: DCS) gas, trichlorosilane (SiHCl3, abbreviated as: TCS) gas, hexachlorodisilane (Si2Cl6, abbreviated as: HCDS) gas, octachlorotrisilane (Si3Cl8, abbreviated as: OCTS) gas, bromosilane gases such as tetrabromosilane (SiBr4) gas, and iodosilane gases such as tetraiodosilane (SiI4) gas can be used.

[0130] [Step D2]

[0131] In this step, NH 3 gas is supplied to the wafer 200 in the process chamber 201 , that is, the Si-containing layer formed on the surface of the substrate 200 a .

[0132] Specifically, valve 243c is opened to allow NH3 gas to flow into gas supply pipe 232c. NH3 gas is flow-regulated by MFC241c, supplied to processing chamber 201 via nozzle 249c, and exhausted from exhaust port 231a. At this time, NH3 gas is supplied to wafer 200 (NH3 gas supply). At this time, valves 243d and 243e may also be opened to supply N2 gas to processing chamber 201 via nozzles 249a and 249b, respectively.

[0133] The treatment conditions in this step may include:

[0134] NH3 gas supply flow rate: 10~10000sccm

[0135] NH3 gas supply time: 1 to 60 seconds, preferably 5 to 50 seconds

[0136] Treatment pressure: 1-4000Pa, preferably 1-1333Pa.

[0137] The other processing conditions are the same as those in step B.

[0138] By supplying NH3 gas to the wafer 200 under the above conditions, at least a portion of the Si-containing layer formed on the surface of the substrate 200a is nitrided. By nitriding the Si-containing layer, a layer containing Si and N, namely a silicon nitride layer (SiN layer) is formed on the surface of the substrate 200a. When the SiN layer is formed, impurities such as Cl contained in the Si-containing layer constitute a gaseous substance containing at least Cl during the nitridation reaction of the Si-containing layer by the NH3 gas, and are discharged from the processing chamber 201. As a result, the SiN layer becomes a layer with less impurities such as Cl than the Si-containing layer formed in step D1. It should be noted that the surfaces of the substrate 200b and the protective film 200e are not nitrided and are maintained when this step is implemented. That is, the surfaces of the substrate 200b and the protective film 200e are not nitrided (NH termination), and the F-terminated state is stably maintained.

[0139] After the SiN layer is formed on the surface of the substrate 200a, the valve 243c is closed to stop the supply of NH3 gas into the processing chamber 201. Then, the gas remaining in the processing chamber 201 is removed (purged) from the processing chamber 201 by the same processing steps as the purging in step A.

[0140] As a reaction gas (film-forming gas), in addition to NH 3 gas, for example, a hydrogen nitride-based gas such as diazenium (N 2 H 2 ) gas, hydrazine (N 2 H 4 ) gas, or N 3 H 8 gas can be used.

[0141] 〔Number of times the regulations are implemented〕

[0142] By making the above steps D1 and D2 be performed non-simultaneously, i.e., asynchronously, for a predetermined number of times (n times, where n is an integer greater than 1), Figure 5 As shown in (f), a SiN film can be selectively formed on the surface of the substrate 200a among the substrates 200a, 200b and the protective film 200e exposed on the surface of the wafer 200. The above cycle is preferably repeated multiple times. That is, it is preferred that the thickness of the SiN layer formed in each cycle is thinner than the desired film thickness, and the above cycle is repeated multiple times until the film thickness of the film formed by stacking the SiN layers reaches the desired film thickness.

[0143] It should be noted that when performing steps D1 and D2, the F-terminated films on the surfaces of the substrate 200b and the protective film 200e do not disappear but are maintained, so that the inhibitor function is maintained, and no SiN film is formed on the surfaces of the substrate 200b and the protective film 200e. However, in the case where the modification of the surfaces of the substrate 200b and the protective film 200e is insufficient due to some reason, there is a case where a very small amount of SiN film is formed on the surfaces of the substrate 200b and the protective film 200e, but even in this case, the thickness of the SiN film formed on the surfaces of the substrate 200b and the protective film 200e is much thinner than the thickness of the SiN film formed on the surface of the substrate 200a. In this specification, "a SiN film is selectively formed on the surface of the substrate 200a" on the substrates 200a, 200b and the protective film 200e not only includes the case where no SiN film is formed on the respective surfaces of the substrate 200b and the protective film 200e, but also includes the case where a very thin SiN film is formed on the respective surfaces of the substrate 200b and the protective film 200e as described above.

[0144] (Post-purge and atmospheric pressure recovery)

[0145] After the selective formation of the SiN film on the substrate 200a is completed, N2 gas is supplied as a purge gas from the nozzles 249a to 249c into the processing chamber 201, and the gas is exhausted from the exhaust port 231a. Thus, the processing chamber 201 is purged, and the gas and reaction byproducts remaining in the processing chamber 201 are removed from the processing chamber 201 (post-purge). After that, the atmosphere in the processing chamber 201 is replaced with an inactive gas (inactive gas replacement), and the pressure in the processing chamber 201 is restored to normal pressure (atmospheric pressure recovery).

[0146] (Wafer boat unloading and wafer removal)

[0147] The sealing cover 219 is lowered by the wafer boat elevator 115, and the lower end of the manifold 209 is opened. Then, the processed wafer 200 is carried out from the lower end of the manifold 209 to the outside of the reaction tube 203 while being supported by the wafer boat 217 (wafer boat unloading). After the wafer boat is unloaded, the gate 219s is moved, and the lower end opening of the manifold 209 is sealed by the gate 219s via the O-ring 220c (gate closing). After being carried out to the outside of the reaction tube 203, the processed wafer 200 is taken out from the wafer boat 217 (wafer taking out).

[0148] It should be noted that if Figure 5As shown in (g), the F capping present on the surfaces of the substrate 200b and the protective film 200e reacts with a predetermined reactant, specifically, with moisture (H2O) in the atmosphere and dissociates when the processed wafer 200 is exposed to the atmosphere. That is, the F capping present on the surfaces of the substrate 200b and the protective film 200e can be removed by exposing the processed wafer 200 to the atmosphere. By removing the F capping from the surfaces of the substrate 200b and the protective film 200e, the surface states of the substrate 200b and the protective film 200e are restored, and film formation processing can be performed on the surfaces of the substrate 200b and the protective film 200e in subsequent steps.

[0149] (3) Effects of this embodiment

[0150] According to this aspect, one or more of the following effects can be obtained.

[0151] (a) By performing steps A to D, a SiN film can be selectively formed on the surface of the substrate 200a among the substrates 200a, 200b, and 200c exposed on the surface of the wafer 200. Thus, for example, when manufacturing a semiconductor device, the process can be simplified (patterning including photolithography can be omitted). As a result, the productivity of the semiconductor device can be improved and the manufacturing cost can be reduced.

[0152] (b) By forming a SiO film as a protective film 200e on the surface of the substrate 200c in step A, the F2 gas does not contact the surface of the substrate 200c in step C, thereby suppressing etching damage to the surface of the substrate 200c. That is, in step C, while suppressing etching damage to the substrate 200c caused by the F2 gas, the surfaces of the substrate 200b and the protective film 200e can be modified.

[0153] Here, the case where the natural oxide film (SiO film) formed on the surface of the substrate 200c before DHF cleaning is used as a protective film is also considered. However, since the thickness of the natural oxide film is uneven, when the natural oxide film is used as a protective film, there is a case where the F2 gas contacts the substrate 200c at a portion where the thickness of the natural oxide film is thin in step C, and the surface of the substrate 200c is etched and damaged by etching.

[0154] (c) The thickness of the protective film 200e is as thin as Therefore, there is a case where there is no need to perform a process of removing the protective film 200e after the selective growth is completed. In this case, the manufacturing process of the semiconductor device can be simplified, the productivity of the semiconductor device can be improved, and the manufacturing cost can be reduced. However, in the case where the SiO film formed as the protective film 200e affects the characteristics of the device, it is preferred to remove the protective film 200e. In this case, it can be removed by, for example, DHF cleaning.

[0155] (d) DHF cleaning is performed before step A to remove the natural oxide film 200d formed on the surface of the substrate 200a, and the surface of the substrate 200a is exposed, so that a SiN film with high uniformity of film thickness can be formed on the surface of the substrate 200a in step D. In addition, by removing the natural oxide film 200d formed on the surface of the substrate 200c and exposing the surface of the substrate 200c, the surface of the substrate 200c can be uniformly oxidized in step A, so that a protective film 200e with high uniformity of film thickness can be formed on the surface of the substrate 200c.

[0156] (e) In step B, the amount of Si selectively (preferentially) adsorbed on the substrate 200b and the protective film 200e can be made substantially uniform over the entire surface area of ​​the substrate 200b and the protective film 200e. Thus, in step C, the entire surface area of ​​the substrate 200b and the protective film 200e can be substantially uniformly modified. As a result, in step D, the formation of a SiN film on the substrate 200b and the protective film 200e can be substantially uniformly and reliably suppressed over the entire surface area of ​​the substrate 200b and the protective film 200e. That is, the selectivity in the selective growth can be improved.

[0157] (f) After performing step D, the processed wafer 200 is exposed to the atmosphere, so that the F-terminated inhibitors existing on the surfaces of the substrate 200b and the protective film 200e can be eliminated. In this way, since the F-terminated inhibitors can be easily removed, there is no need to set up a separate process for removing the inhibitors, which can simplify the manufacturing process of the semiconductor device, improve the productivity of the semiconductor device, and reduce the manufacturing cost.

[0158] (g) Since at least any one of steps A to D, preferably each of steps A to D is performed in a non-plasma atmosphere, plasma damage to the wafer 200 can be avoided, and the method can be applied to processes where plasma damage is a concern.

[0159] (h) The above-mentioned effects can be similarly obtained in the following situations: when using oxygen-containing gases other than O2 gas, when using aminosilane-based gases other than SiHR3 gas, when using fluorine-containing gases other than F2 gas, when using raw material gases other than SiCl4 gas, when using reaction gases other than NH3 gas, and when using inert gases other than N2 gas.

[0160] <Other aspects of the present invention>

[0161] The embodiments of the present invention have been specifically described above, but the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the gist of the present invention.

[0162] In the above scheme, an example is described in which an aminosilane-based gas is supplied to the wafer 200 in step B so that Si is selectively adsorbed on the surfaces of the substrate 200b and the protective film 200e, and a F-containing gas is supplied to the wafer 200 in step C so that Si adsorbed on the surfaces of the substrate 200b and the protective film 200e reacts with the F-containing gas to modify the surfaces of the substrate 200b and the protective film 200e in a non-etching manner, but the present invention is not limited to such a scheme. For example, in step C, a F-containing gas may be supplied in an atmosphere in which a pseudo-catalyst is present to generate F-containing radicals, and the surfaces of the substrate 200b and the protective film 200e may be modified in a non-etching manner using the F-containing radicals generated in this way. That is, in step C, F-containing gas may be supplied into the processing chamber 201 containing the pseudo-catalyst to generate F-containing radicals, and the radicals generated in this way may be supplied to the surface of the wafer 200, thereby selectively (preferentially) modifying the surfaces of the substrate 200b and the protective film 200e in a non-etching manner. In this case, step B may not be performed.

[0163] Here, the pseudo-catalyst is a substance that promotes the decomposition of the F-containing gas and promotes the generation of F-containing radicals from the F-containing gas. The pseudo-catalyst effect generated by contacting the F-containing gas with the pseudo-catalyst can promote the generation of F-containing radicals from the F-containing gas, and can efficiently generate F-containing radicals.

[0164] As a pseudo-catalyst, for example, solid Si whose outermost surface is not covered by a natural oxide film (SiO film) can be used, that is, a bare Si component in which the Si material is exposed on the outermost surface can be used. As such a component, for example, a Si wafer, such as a bare Si wafer (hereinafter referred to as a bare wafer), can be used after the natural oxide film formed on the outermost surface is removed by DHF cleaning or the like. It should be noted that a natural oxide film is formed on the outermost surface of the bare wafer stored in the atmosphere, and the Si material is not exposed on its outermost surface. In this state, the bare wafer cannot be directly used as a pseudo-catalyst. In order for the bare wafer to function as a pseudo-catalyst, it is necessary to remove the natural oxide film formed on the outermost surface of the bare wafer during step C to form a state in which the Si material is exposed on the outermost surface.

[0165] When a bare wafer is used as a pseudo-catalyst, the bare wafer with Si material exposed on the outermost surface can be held at a predetermined position of the wafer boat 217 together with the wafer 200 to be processed, and the wafer boat 217 is moved into the processing chamber 201 in this state, so that the bare wafer as the pseudo-catalyst is accommodated in the processing chamber 201. It should be noted that in this case, it is preferred to alternately load the bare wafer as the pseudo-catalyst and the wafer 200 to be processed into the wafer boat 217, so that the bare wafer is arranged directly above the substrate 200b and directly above the protective film 200e in a manner that the upper surface of the wafer 200 to be processed faces (opposes) the surface of the bare wafer as the pseudo-catalyst. In this case, in step C, by bringing the F-containing gas into contact with the bare wafer as the pseudo-catalyst, F-containing radicals can be efficiently generated, and the F-containing radicals efficiently generated in this way can be efficiently supplied to the substrate 200b and the protective film 200e, respectively. As a result, the surfaces of the substrate 200b and the protective film 200e can be appropriately modified.

[0166] The processing steps and processing conditions in the selective growth in this case can be set to be the same as the processing steps and processing conditions of the above scheme, except that a bare wafer serving as a pseudo-catalyst is placed on the wafer boat 217 and step B is not performed, as shown in the following gas supply timing.

[0167]

[0168] In this case, the same effect as the above scheme can be obtained. In addition, in step C, the F-containing gas is supplied in the atmosphere in the presence of the pseudo-catalyst, and compared with the case where the F-containing gas is supplied in the atmosphere in the absence of the pseudo-catalyst, the generation of F-containing radicals in the processing chamber 201 can be promoted and the amount of the generated F-containing radicals can be increased. As a result, in step C, the modification of the surfaces of the substrate 200b and the protective film 200e can be promoted, and the selective formation of the SiN film on the surface of the substrate 200a can be appropriately performed. In addition, by using the pseudo-catalyst, the processing temperature in step C can be lowered, and the etching of the surface of the substrate 200a in step C and the etching damage to the surface of the substrate 200a can be effectively suppressed.

[0169] It should be noted that, as a pseudo-catalyst, a Si plate (Si plate), a Si chip (Si chip), a Si small piece (Si small piece), a Si block (Si block), etc. may be used instead of a bare wafer. When the above materials are used as pseudo-catalysts, similarly to the case of using a bare wafer as a pseudo-catalyst, it is necessary to remove the natural oxide film formed on the outermost surface thereof, so that the Si material is exposed on the outermost surface.

[0170] In addition, before performing step C, a Si film (pre-coating) may be formed on the surface of the components in the processing chamber 201 (the inner wall of the reaction tube 203, the surface of the wafer boat 217, etc.) and used as a pseudo-catalyst. The Si film as the pre-coating film can be formed by a CVD method using a silane-based gas such as monosilane (SiH4) gas. The Si film may be an amorphous (non-crystalline) Si film, a polycrystalline (polycrystalline) Si film, or an amorphous and polycrystalline mixed crystal Si film.

[0171] The processing conditions for forming the Si film include:

[0172] SiH4 gas supply flow rate: 10~2000sccm

[0173] N2 gas supply flow rate (each gas supply pipe): 0~10000sccm

[0174] Gas supply time: 10 to 400 minutes

[0175] Processing temperature: 450-550°C, preferably 450-530°C

[0176] Processing pressure: 1~900Pa.

[0177] In this case, in step C, by bringing the F-containing gas into contact with the Si film (pre-coating film) as a pseudo-catalyst, F-containing radicals can be efficiently generated, and the F-containing radicals efficiently generated in this way can be efficiently supplied to the substrate 200b and the protective film 200e. As a result, the surfaces of the substrate 200b and the protective film 200e can be appropriately modified.

[0178] It should be noted that, as a pre-coating film, in addition to Si film, SiN film, silicon carbide film (SiC film), silicon carbonitride film (SiCN film), silicon-rich SiN film (SiRN film), silicon-rich SiC film (SiRC film), silicon-rich SiCN film (SiRCN film), etc. can also be used. That is, as a pre-coating film, in addition to Si, a Si-containing film containing C and N can also be used. For SiN film, SiC film, SiCN film, SiRN film, SiRC film, and SiRCN film as pre-coating films, for example, ethylmethylaminosilane (SiH3 [N (CH3) (C2H5)]) gas, dimethylaminosilane (SiH3 [N (CH3) 2]) gas, diisopropylaminosilane (SiH3 [N (C3H7) 2]) gas, di-sec-butylaminosilane (SiH3 [H (C4H9) 2]) gas and other aminosilane-based gases can be used and formed by CVD method. The processing conditions at this time can be the same as those for forming the Si film as the pre-coating film. It should be noted that the aminosilane-based gas is a gas containing Si and amino groups, or a gas containing at least Si, N, and C as constituent elements.

[0179] In the above case, the F-containing gas can also be brought into contact with the SiN film, SiC film, SiCN film, SiRN film, SiRC film, SiRCN film (pre-coating film) as a pseudo-catalyst in step C, thereby efficiently generating F-containing radicals, and the F-containing radicals efficiently generated in this way can be efficiently supplied to the substrate 200b and the protective film 200e, respectively. As a result, the surfaces of the substrate 200b and the protective film 200e can be appropriately modified.

[0180] Regarding the processing steps and processing conditions in the selective growth when the above-mentioned pre-coated film is used as a pseudo-catalyst, except that the above-mentioned film is pre-coated on the surface of the component in the processing chamber 201 and step B is not performed, it can be set to be the same as the processing steps and processing conditions of the above-mentioned method. In the case of using the pre-coated film as a pseudo-catalyst in this way, the same effect as the case of using a bare wafer as a pseudo-catalyst can be obtained. It should be noted that the pre-coated film in this case can also be called a pseudo-catalyst film or a pseudo-catalyst pre-coated film.

[0181] In addition, after the wafer 200 to be processed is accommodated in the processing chamber 201 and before step C is performed, a Si film is formed on the surface of the wafer 200, i.e., on the surface of each of the substrates 200a, 200b and the protective film 200e, and the Si film is used as a pseudo-catalyst, i.e., a pseudo-catalyst film. As the pseudo-catalyst film, in addition to the Si film, a SiN film, a SiC film, a SiCN film, a SiRN film, a SiRC film, a SiRCN film, etc. can also be used. That is, as the pseudo-catalyst film, in addition to Si, a Si-containing film containing C and N can also be used. The gas and processing conditions used when forming the Si film, SiN film, SiC film, SiCN film, SiRN film, SiRC film, and SiRCN film as the pseudo-catalyst film can be set to be the same as the gas and processing conditions used when forming the above-mentioned pre-coating film.

[0182] In the above case, in step C, by bringing the F-containing gas into contact with the pseudo-catalyst film, F-containing radicals can be efficiently generated, and the F-containing radicals efficiently generated in this way can be supplied to each of the substrate 200b and the protective film 200e. That is, the surfaces of the substrate 200b and the protective film 200e can be modified in an F-terminated manner. It should be noted that at this time, the pseudo-catalyst film formed on the surface of the substrate 200a is etched, and the adsorption site is exposed on the surface of the substrate 200a. At this time, there is also a case where the surface of the substrate 200a is also slightly etched, but even in this case, the etching amount is small, and the adsorption site on its surface is maintained. It should be noted that since the substrate 200b and the protective film 200e are composed of SiO films and have strong Si-O bonds, their surfaces are not etched, but the surfaces are appropriately F-terminated and appropriately modified.

[0183] The processing steps and processing conditions in the selective growth when the pseudo-catalyst film is used can be the same as those in the above-mentioned manner, except that the pseudo-catalyst film is formed on the surface of the wafer 200 and step B is not performed. Even when a Si film, SiN film, SiC film, SiCN film, SiRN film, SiRC film, SiRCN film, etc. is used as a pseudo-catalyst, the same effect as when a bare wafer is used as a pseudo-catalyst can be obtained.

[0184] In addition, for example, as a pseudo-catalyst, not only solid pseudo-catalysts such as bare wafers, Si plates, Si chips, Si chips, Si blocks, Si-containing pre-coated films, and Si-containing pseudo-catalyst films can be used, but also gaseous pseudo-catalysts can be used. As a gaseous pseudo-catalyst, i.e., a pseudo-catalyst gas, a gas that promotes the decomposition of the F-containing gas by contact with the F-containing gas and generates F-containing free radicals from the F-containing gas can be used. As a pseudo-catalyst gas, specifically, for example, at least one of O2 gas, N2O gas, N2O gas, NO gas, HF gas, NH3 gas, and hydrogen (H2) gas can be used. The supply of the above gases can be carried out simultaneously with the supply of the F-containing gas into the processing chamber 201 using nozzles 249a, 249c, etc., for example.

[0185] In this case, in step C, the F-containing gas and the pseudo-catalyst gas are simultaneously supplied into the processing chamber 201, thereby supplying the F-containing gas in an atmosphere in which the pseudo-catalyst gas exists. At this time, the F-containing gas can be brought into contact with the pseudo-catalyst gas, thereby efficiently generating F-containing radicals, and the F-containing radicals efficiently generated in this manner can be efficiently supplied to each of the substrate 200b and the protective film 200e. As a result, the surfaces of each of the substrate 200b and the protective film 200e can be appropriately modified. It should be noted that as long as the F-containing gas and the pseudo-catalyst gas can be mixed in the processing chamber 201, the F-containing gas and the pseudo-catalyst gas can be supplied to the processing chamber 201 alternately or intermittently.

[0186] The processing steps and processing conditions in the selective growth in this case can be the same as those in the above-mentioned method, except that the F-containing gas and the pseudo-catalyst gas are supplied to the processing chamber 201 and step B is not performed. When the F-containing gas and the pseudo-catalyst gas are supplied in this way, the same effect as when a bare wafer is used as a pseudo-catalyst can be obtained. In addition, when a gaseous pseudo-catalyst is used, the processing temperature in step C can be lowered, and etching of the surface of the substrate 200a in step C and etching damage to the surface of the substrate 200a can be effectively suppressed.

[0187] It should be noted that the so-called "catalyst" refers to a substance that does not change before and after a chemical reaction, but changes the reaction rate. The above substances exemplified as pseudocatalysts all have a catalytic effect of promoting the generation of F-containing free radicals, but among them, there are also substances that themselves change before and after the chemical reaction. For example, NO gas has a catalytic effect, but when reacting with F-containing gas, there is a situation where part of the molecular structure is decomposed and it itself changes before and after the chemical reaction. In this specification, a substance that changes the reaction rate even though it changes before and after the chemical reaction is called a "pseudocatalyst".

[0188] In addition, for example, in step C, the generation of F-containing radicals from the F-containing gas may be promoted by activating (exciting) the F-containing gas by plasma, heating, light irradiation, etc. In these cases, the same effects as those in the above-mentioned manner can be obtained. In addition, by activating the F-containing gas by plasma, heating, light irradiation, etc. in step C, the generation of F-containing radicals in the processing chamber 201 can be promoted and the amount of generated F-containing radicals can be increased compared to the case where the F-containing gas is not activated by them. As a result, the modification of the surfaces of the substrate 200b and the protective film 200e can be promoted in step C, and the selective formation of the SiN film on the surface of the substrate 200a can be appropriately performed. In addition, the processing temperature in step C can also be lowered. It should be noted that, in the case of using plasma, in order to suppress plasma damage to the wafer 200 and the components in the processing chamber 201, it is preferable to use a remote plasma method in which the F-containing gas is activated by plasma in a remote plasma unit disposed outside the processing chamber 201 and then supplied to the processing chamber 201.

[0189] In addition, in the above scheme, an example of sequentially performing steps A, B, C, and D on a wafer 200 having a substrate 200a including a SiN film, a substrate 200b including a SiO film, and a substrate 200c including a single crystal Si exposed on the surface is described, but the present invention is not limited to such a scheme. For example, a substrate including a SiCN film, a silicon boron nitride film (SiBN film), a silicon boron carbonitride film (SiBCN film), or a silicon boron carbide film (SiBC film) may be exposed on the surface of the wafer 200 instead of the substrate 200a including a SiN film. In addition, for example, a substrate including a silicon oxycarbide film (SiOC film), a silicon oxynitride film (SiON film), or a silicon oxycarbonitride film (SiOCN film) may be exposed instead of the substrate 200b including a SiO film. In addition, for example, instead of the substrate 200c including single crystal Si, a substrate including an epitaxial silicon film (Epi-Si film), a polycrystalline silicon film (poly-Si film (polycrystalline Si film)), or an amorphous silicon film (a-Si film (amorphous Si film)) may be exposed. In addition, for example, not only the substrate 200a including a SiN film, the substrate 200b including a SiO film, and the substrate 200c including single crystal Si may be exposed, but also a substrate including a conductive metal film such as a tungsten film (W film), a tungsten nitride film (WN film), or a titanium nitride film (TiN film) may be exposed. In addition, instead of the substrate 200a including a SiN film, a substrate including the above-mentioned metal film may be exposed. In these cases, the same effects as those of the above-mentioned schemes can be obtained. That is, a film can be selectively formed on the surface of the substrate 200a and the surface of the above-mentioned metal film while avoiding film formation on the substrates 200b and 200c.

[0190] In addition, in the above scheme, in step B, an example of using monoaminosilane gas as an aminosilane gas is described, but the present invention is not limited to such a scheme. For example, in step B, as an aminosilane gas, diaminosilane gas or triaminosilane gas may be used instead of monoaminosilane gas. In the above case, the same effect as the above scheme can be obtained. Among them, in step B, the fewer the number of amino groups contained in one molecule of the aminosilane gas used, the higher the adsorption density of Si on the surfaces of the substrate 200b and the protective film 200e, and in step C, the higher the density of SiF capping formed on the surfaces of the substrate 200b and the protective film 200e. As a result, the effect of hindering the film formation on the surfaces of the substrate 200b and the protective film 200e can be improved in step D. In this regard, as an aminosilane gas, it is particularly preferred to use a monoaminosilane having one amino group contained in one molecule.

[0191] In addition, in the above scheme, in step D, an example of performing a cycle of non-simultaneous steps D1 and D2 for a predetermined number of times is described, but the present invention is not limited to such a scheme. For example, in step D, before starting the cycle of non-simultaneous steps D1 and D2, a step of supplying NH3 gas to the chip 200 in the processing chamber 201 for a predetermined time (NH3 pre-flow) may be performed, that is, to the chip 200 after selectively modifying the surface of the substrate 200b and the protective film 200e in the substrate 200a, 200b and the protective film 200e. In this case, the F terminations existing on the surfaces of the substrate 200b and the protective film 200e will not disappear but will be stably maintained, so that the same effect as the above scheme can be obtained. In addition, the adsorption site on the surface of the substrate 200a can be optimized, thereby improving the quality of the SiN film formed on the substrate 200a.

[0192] In addition, in the above scheme, an example of using SiCl4 gas as a raw material gas and NH3 gas as a reaction gas in step D is described, but the present invention is not limited to such a scheme. For example, in step D, as a raw material gas, in addition to SiCl4 gas, the above-mentioned chlorosilane gas, titanium tetrachloride (TiCl4) gas and other halogenated metal gases can also be used. In addition, for example, as a reaction gas, in addition to N-containing gases such as NH3 gas, oxygen (O2) gas and other O-containing gases, triethylamine ((C2H5)3N, abbreviated as: TEA) gas and other gases containing N and C, propylene (C3H6) gas and other C-containing gases, boron trichloride (BCl3) gas and other boron (B) containing gases can also be used. Furthermore, a SiON film, SiCN film, SiOCN film, SiOC film, SiBN film, SiBCN film, TiN film, titanium oxynitride film (TiON film) or the like can be formed on the surface of the unmodified substrate 200a among the substrates 200a, 200b and the protective film 200e by the gas supply sequence shown below. The F-terminated film formed on the surfaces of the substrates 200b and 200c is very stable, so in the above case, that is, when a gas containing an OH group such as water vapor (H2O gas) is not used as the film-forming gas, the same effect as the above scheme can be obtained.

[0193]

[0194]

[0195]

[0196]

[0197]

[0198]

[0199]

[0200]

[0201] In addition, in the above scheme, an example of performing DHF cleaning on the wafer 200 before performing selective growth is described, but the present invention is not limited to such a scheme. For example, as shown in the case where the above selective growth is performed in a manner that the substrates 200a and 200c are not exposed to the atmosphere after film formation on the substrate 200a, DHF cleaning may not be performed when the natural oxide film 200d is not formed on the surface of the substrates 200a and 200c.

[0202] It is preferred that the recipe used for each treatment is prepared separately according to the treatment content, and is stored in advance in the storage device 121c via the electrical communication line and the external storage device 123. In addition, it is preferred that when each treatment starts, the CPU 121a appropriately selects an appropriate recipe from the multiple recipes stored in the storage device 121c according to the treatment content. In this way, films of various film types, composition ratios, film qualities, and film thicknesses can be formed with good reproducibility in one substrate processing device. In addition, the burden on the operator can be reduced, operational errors can be avoided, and each treatment can be started quickly.

[0203] The above-mentioned process is not limited to the case of newly created, and can also be prepared by, for example, changing an existing process installed in a substrate processing device. In the case of changing a process, the changed process can also be installed in the substrate processing device via an electrical communication line or a recording medium recording the corresponding process. In addition, the input / output device 122 of the existing substrate processing device can be operated to directly change the existing process installed in the substrate processing device.

[0204] In the above scheme, an example of forming a film using a batch-type substrate processing device that processes multiple substrates at a time is described. The present invention is not limited to the above scheme, and for example, it can also be appropriately applied to the case of forming a film using a single-type substrate processing device that processes one or more substrates at a time. In addition, in the above scheme, an example of forming a film using a substrate processing device having a hot wall type processing furnace is described. The present invention is not limited to the above scheme, and it can also be appropriately applied to the case of forming a film using a substrate processing device having a cold wall type processing furnace.

[0205] When the above substrate processing apparatus is used, each process can be performed under the same processing steps and processing conditions as those of the above scheme, and the same effects as those of the above scheme can be obtained.

[0206] The above-mentioned means can be used in combination as appropriate. The processing steps and processing conditions at this time can be, for example, the same as the processing steps and processing conditions of the above-mentioned means.

[0207] Example

[0208] Prepare multiple wafers with SiN film (first substrate), SiO film (second substrate) and single crystal Si (third substrate) exposed on the surface, and use DHF aqueous solution to clean the surface of each wafer to remove the SiN film in each wafer and the natural oxide film formed on the surface of the single crystal Si. Figure 1 The substrate processing apparatus shown in the figure performed a process of forming a SiN film on each wafer, and prepared two evaluation samples (samples 1 and 2).

[0209] When preparing Sample 1 (Example), steps A to D in the above scheme were respectively carried out. The processing conditions in steps A to D were set to predetermined conditions within the range of the processing conditions described in the above scheme.

[0210] When preparing sample 2 (comparative example), step A in the above scheme was not performed, and steps B to D were performed respectively. The processing conditions of each of steps B to D were set to the same conditions as those of each of steps B to D when preparing sample 1.

[0211] By observing both the SEM image and the TEM image of the cross section of Samples 1 and 2, it was confirmed that the surface of the third substrate was not damaged by etching in Sample 1 in which Step A was implemented. In contrast, it was confirmed that the surface of the third substrate was damaged by etching in Sample 2 in which Step A was not implemented. It should be noted that in both Samples 1 and 2, it was confirmed that the SiN film could be selectively formed only on the surface of the first substrate.

Claims

1. A method for manufacturing a semiconductor device, comprising the following steps: (a) a process of supplying an oxygen-containing gas as a processing gas to a substrate having a first substrate including a nitride film containing silicon and nitrogen and not containing oxygen, a second substrate including an oxide film containing silicon and oxygen, and a third substrate including single crystal silicon, an epitaxial silicon film, a polycrystalline silicon film, or an amorphous silicon film on its surface, under conditions where oxidation of the first substrate is suppressed, and selectively forming an oxide film containing silicon and oxygen as a protective film on the surface of the third substrate; (b1) supplying an aminosilane-based gas to the substrate after the protective film is selectively formed on the surface of the third substrate, thereby suppressing the adsorption of silicon contained in the aminosilane-based gas to the surface of the first substrate and causing the silicon contained in the aminosilane-based gas to be selectively adsorbed to the surface of the second substrate and the surface of the protective film; (b2) supplying a fluorine-containing gas to the substrate after silicon is selectively adsorbed on the surface of the second base and the surface of the protective film, so that the surface of the second base and the surface of the protective film are modified in a fluorine-terminated manner; and (c) A step of supplying a film forming gas to the substrate after the surface of the second base is modified to selectively form a film on the surface of the first base.

2. The method for manufacturing a semiconductor device according to claim 1, wherein: The protective film includes a silicon oxide film.

3. The method for manufacturing a semiconductor device according to claim 1, wherein: In (a), the surface of the third base is oxidized to form the protective film.

4. The method for manufacturing a semiconductor device according to claim 1, wherein: In (a), the surface of the third substrate is oxidized by dry oxidation.

5. The method for manufacturing a semiconductor device according to claim 1, wherein: In (a), the surface of the third substrate is oxidized at a pressure lower than atmospheric pressure.

6. The method for manufacturing a semiconductor device according to claim 1, wherein: In (a), the surface of the third base is oxidized under the condition that the surface of the first base is not oxidized.

7. The method for manufacturing a semiconductor device according to claim 1, wherein: In (b2), the surface of the protective film is modified by fluorine termination instead of etching.

8. The method for manufacturing a semiconductor device according to claim 1, wherein: In (b2), the surface of the second substrate is modified by fluorine termination instead of etching.

9. The method for manufacturing a semiconductor device according to claim 1, wherein: In (b2), the fluorine-containing gas is supplied to the substrate in an atmosphere in which silicon is present.

10. The method for manufacturing a semiconductor device according to claim 1, wherein: The space where the substrate is located is purged between (b1) and (b2).

11. The method for manufacturing a semiconductor device according to claim 1, wherein: In (b1), silicon contained in the aminosilane-based gas is adsorbed on the surface of the second base under self-limiting conditions.

12. The method for manufacturing a semiconductor device according to claim 1, wherein: In (b1), silicon contained in the aminosilane-based gas is adsorbed on the surface of the protective film under self-limiting conditions.

13. The method for manufacturing a semiconductor device according to claim 1, wherein: Prior to performing step (a), there is further performed a step (d) of removing a natural oxide film formed on the surface of the substrate.

14. The method for manufacturing a semiconductor device according to claim 13, wherein: In (d), the material of the first base is stripped to be exposed.

15. The method for manufacturing a semiconductor device according to claim 14, wherein: In (d), the material of the third base is stripped to be exposed.

16. The method for manufacturing a semiconductor device according to claim 1, wherein: The first substrate includes at least one nitride film selected from the group consisting of silicon nitride film, silicon carbonitride film, silicon boron nitride film, and silicon boron carbon nitride film, and the second substrate includes at least one oxide film selected from the group consisting of silicon oxide film, silicon carbon oxide film, silicon nitride oxide film, and silicon oxycarbon nitride film.

17. The method for manufacturing a semiconductor device according to claim 1, wherein: The first base includes a silicon nitride film, and the second base includes a silicon oxide film.

18. A substrate processing method comprising the following steps: (a) a process of supplying an oxygen-containing gas as a processing gas to a substrate having a first substrate including a nitride film containing silicon and nitrogen and not containing oxygen, a second substrate including an oxide film containing silicon and oxygen, and a third substrate including single crystal silicon, an epitaxial silicon film, a polycrystalline silicon film, or an amorphous silicon film on its surface, under conditions where oxidation of the first substrate is suppressed, and selectively forming an oxide film containing silicon and oxygen as a protective film on the surface of the third substrate; (b1) supplying an aminosilane-based gas to the substrate after the protective film is selectively formed on the surface of the third substrate, thereby suppressing the adsorption of silicon contained in the aminosilane-based gas to the surface of the first substrate and causing the silicon contained in the aminosilane-based gas to be selectively adsorbed to the surface of the second substrate and the surface of the protective film; (b2) supplying a fluorine-containing gas to the substrate after silicon is selectively adsorbed on the surface of the second base and the surface of the protective film, so that the surface of the second base and the surface of the protective film are modified in a fluorine-terminated manner; and (c) A step of supplying a film forming gas to the substrate after the surface of the second base is modified to selectively form a film on the surface of the first base.

19. A substrate processing device comprising: a process gas supply system that supplies process gas to the substrate; an aminosilane-based gas supply system for supplying an aminosilane-based gas to a substrate; a fluorine-containing gas supply system for supplying a fluorine-containing gas to the substrate; a film-forming gas supply system that supplies a film-forming gas to the substrate; and A control unit configured to control the processing gas supply system, the aminosilane-based gas supply system, the fluorine-containing gas supply system, and the film-forming gas supply system so as to perform the following processing: (a) supplying an oxygen-containing gas as the processing gas to a substrate having a first substrate including a nitride film containing silicon and nitrogen and not containing oxygen on its surface, a second substrate including an oxide film containing silicon and oxygen, and a third substrate including a single crystal silicon, an epitaxial silicon film, a polycrystalline silicon film, or an amorphous silicon film, under a condition where oxidation of the first substrate is suppressed, thereby selectively forming an oxide film containing silicon and oxygen on the surface of the third substrate as a protective film; (b1) supplying the aminosilane-based gas to the substrate after the protective film is selectively formed on the surface of the third substrate, thereby suppressing adsorption of silicon contained in the aminosilane-based gas to the surface of the first substrate and causing the silicon contained in the aminosilane-based gas to be selectively adsorbed to the surface of the second substrate and the surface of the protective film; (b2) supplying the fluorine-containing gas to the substrate after silicon is selectively adsorbed on the surface of the second base and the surface of the protective film, so that the surface of the second base and the surface of the protective film are modified in a fluorine-terminated manner; and (c) supplying the film-forming gas to the substrate after modifying the surface of the second base to selectively form a film on the surface of the first base.

20. A computer-readable recording medium having a program recorded thereon for causing a substrate processing apparatus to execute the following steps via a computer: (a) a step of supplying an oxygen-containing gas as a processing gas to a substrate having a first substrate including a nitride film containing silicon and nitrogen and not containing oxygen, a second substrate including an oxide film containing silicon and oxygen, and a third substrate including a single crystal silicon, an epitaxial silicon film, a polycrystalline silicon film, or an amorphous silicon film on its surface, under conditions where oxidation of the first substrate is suppressed, and selectively forming an oxide film containing silicon and oxygen as a protective film on the surface of the third substrate; (b1) supplying an aminosilane-based gas to the substrate after the protective film is selectively formed on the surface of the third substrate, suppressing the adsorption of silicon contained in the aminosilane-based gas to the surface of the first substrate and causing the silicon contained in the aminosilane-based gas to be selectively adsorbed to the surface of the second substrate and the surface of the protective film; (b2) supplying a fluorine-containing gas to the substrate after silicon is selectively adsorbed on the surface of the second base and the surface of the protective film, so that the surface of the second base and the surface of the protective film are modified in a fluorine-terminated manner; and (c) A step of supplying a film forming gas to the substrate after the surface of the second base is modified to selectively form a film on the surface of the first base.

Images