Substrate processing method, semiconductor device manufacturing method, substrate processing apparatus, and recording medium

Abstract

The present invention relates to a substrate processing method, a semiconductor device manufacturing method, a substrate processing apparatus, and a recording medium. A technology for improving embedding characteristics of a film when embedding in a recess is provided. The following processes are performed: (a) a process of supplying a precursor substance to a substrate provided with a recess on a surface, adsorbing at least a part of a molecular structure of a molecule constituting the precursor substance to a surface of a first material constituting the recess, and forming a film formation inhibiting layer on the surface of the first material, wherein an upper surface and a side surface of the recess are constituted by the first material containing a first element, and a bottom surface of the recess is constituted by a second material containing a second element different from the first element; and (b) a process of growing a film on a surface of the second material of the recess by supplying a film formation substance to the substrate on which the film formation inhibiting layer is formed on the surface of the first material.

Description

Technical Field

[0001] This disclosure relates to substrate processing methods, semiconductor device manufacturing methods, substrate processing apparatus, and recording media. Background Technology

[0002] As a step in the manufacturing process of semiconductor devices, a process of forming a film on the surface of a substrate is sometimes performed. In this case, the film is sometimes formed by filling in a recess provided on the surface of the substrate (see, for example, Patent Documents 1 and 2).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2014-183218

[0006] Patent Document 2: Japanese Patent Application Publication No. 2017-069407 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] The purpose of this disclosure is to provide techniques for improving landfill characteristics when using membranes to fill recesses.

[0009] Methods for solving problems

[0010] According to one aspect of this disclosure, the following technology is provided, which performs the following processes:

[0011] (a) A step of supplying a precursor material to a substrate having the aforementioned recesses on its surface, causing at least a portion of the molecular structure constituting the precursor material to adsorb onto the surface of a first material in the recesses, and forming a film-forming inhibition layer on the surface of the first material, wherein the upper surface and side surfaces of the recesses are composed of a first material containing a first element, and the bottom surface is composed of a second material containing a second element different from the first element; and,

[0012] (b) A process in which a film is grown on the surface of the second material in the recess by supplying a film-forming substance to the substrate on which the film-forming inhibition layer is formed on the surface of the first material.

[0013] The effects of the invention

[0014] According to this disclosure, the landfill characteristics can be improved when using a membrane to fill recesses. Attached Figure Description

[0015] [ Figure 1 ] Figure 1This is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferred for use in one embodiment of the present disclosure, showing the processing furnace 202 portion in a longitudinal sectional view.

[0016] [ Figure 2 ] Figure 2 A schematic diagram of a vertical processing furnace of a substrate processing apparatus preferred in one embodiment of this disclosure is shown. Figure 1 The AA-line cross-sectional view shows part of the processing furnace 202.

[0017] [ Figure 3 ] Figure 3 This is a schematic configuration diagram of the controller 121 of a substrate processing apparatus preferred in one embodiment of the present disclosure, which is a block diagram showing the control system of the controller 121.

[0018] [ Figure 4 ] Figure 4 A diagram illustrating the processing sequence in one manner as described in this disclosure.

[0019] [ Figure 5 ] Figure 5 (a) is a partial enlarged cross-sectional view of the substrate surface, in which a stacked structure consisting of alternating layers of a second material (SiGe) and a first material (Si) is provided on the surface, an insulating film is provided on the stacked structure, and a portion of the portion of the sidewall of the stacked structure composed of the second material (SiGe) is removed, thereby creating a recess in the sidewall of the stacked structure with a depth direction parallel to the surface of the substrate (lateral direction). Figure 5 (b) describes the processing sequence used in this method to achieve a surface with... Figure 5 (a) is a magnified cross-section of the substrate surface during the process of forming a silicon oxide carbide (SiOC) film on the substrate. Figure 5 (c) refers to the processing sequence of this method, which has the effect on the surface. Figure 5 (a) is a partial enlarged cross-sectional view of the substrate surface after the substrate has been treated to form a silicon oxide carbide (SiOC) film. Figure 5 (d) refers to the processing sequence using this method, which has the following effect on the surface: Figure 5 (a) is a magnified cross-section of the substrate surface after annealing following the formation of a silicon oxide carbide (SiOC) film on the substrate.

[0020] [ Figure 6 ] Figure 6(a) is a partial enlarged cross-sectional view of the substrate surface, in which a stacked structure consisting of alternating layers of a second material (SiGe) and a first material (Si) is provided on the surface, and an insulating film is provided on the stacked structure. A portion of the portion of the sidewall of the stacked structure composed of the second material (SiGe) is removed, thereby creating a recess in the sidewall of the stacked structure with a depth direction parallel to the surface of the substrate (lateral direction). Figure 6 (b) utilizes conventional film-forming methods to achieve a surface with... Figure 6 (a) is a partial enlarged cross-sectional view of the substrate surface after the substrate has been treated to form a silicon oxide carbide (SiOC) film. Figure 6 (c) is achieved by applying a surface with Figure 6 A magnified cross-section of the substrate surface after etching the substrate of (b) to remove excess film formed on the upper surface of the recess, etc.

[0021] [ Figure 7 ] Figure 7 This is a cross-sectional TEM image of evaluation sample 1 in the example.

[0022] [ Figure 8 ] Figure 8 This is a cross-sectional TEM image of evaluation sample 2 in the example.

[0023] Explanation of reference numerals in the attached figures

[0024] 200 wafers (substrates) Detailed Implementation

[0025] <One way of publishing this text>

[0026] The following is mainly based on Figures 1-4 , Figure 5 (a)~ Figure 5 (d) describes one way of presenting this disclosure. It should be noted that the accompanying drawings used in the following description are schematic diagrams, and the dimensional relationships and ratios of the elements shown in the drawings are not necessarily consistent with reality. Furthermore, the dimensional relationships and ratios of elements in multiple drawings are not necessarily consistent with each other.

[0027] (1) Composition of substrate processing device

[0028] like Figure 1 As shown, the processing furnace 202 has a heater 207 that functions as a temperature regulator (heating unit). The heater 207 is cylindrical and is vertically mounted by being supported on a retaining plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) the gas by heat.

[0029] Inside the heater 207, a reaction tube 203 is arranged concentrically with the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed into a cylindrical shape 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 open upper and lower ends. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 to support the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a sealing member. The reaction tube 203 is installed vertically, just like the heater 207. The processing container (reaction container) is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed in the hollow part of the cylindrical processing container. The processing chamber 201 is configured to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed within the processing chamber 201.

[0030] Nozzles 249a to 249c, serving as the first to third supply units, are respectively provided within the processing chamber 201, passing through the side wall of the manifold 209. Nozzles 249a to 249c are also referred to as the first to third nozzles. Nozzles 249a to 249c are made of heat-resistant materials such as quartz or SiC. Gas supply pipes 232a to 232c are connected to nozzles 249a to 249c respectively. Nozzles 249a to 249c are different nozzles, and each of nozzles 249a and 249c is disposed adjacent to nozzle 249b.

[0031] On gas supply pipes 232a to 232c, mass flow controllers (MFCs) 241a to 241c, serving as flow controllers (flow control units), and valves 243a to 243c, serving as on / off valves, are sequentially installed from the upstream side of the airflow. Gas supply pipes 232d and 232f are connected to the downstream side of gas supply pipe 232a, relative to valve 243a. Gas supply pipes 232e and 232g are connected to the downstream side of gas supply pipe 232b, relative to valve 243b. Gas supply pipe 232h is connected to the downstream side of gas supply pipe 232c, relative to valve 243c. On gas supply pipes 232d to 232h, MFCs 241d to 241h and valves 243d to 243h are sequentially installed from the upstream side of the airflow. Gas supply pipes 232a to 232h are constructed of a metallic material such as SUS.

[0032] like Figure 2As shown, nozzles 249a to 249c are respectively positioned above the inner wall of the reaction tube 203, rising from the lower part of the inner wall and facing the arrangement direction of the wafer 200, in a ring-shaped space when viewed from above. That is, nozzles 249a to 249c are respectively positioned in a region horizontally surrounding the wafer arrangement area, along the side of the wafer arrangement area for arranging the wafers 200. When viewed from above, nozzle 249b is positioned so as to clamp the center of the wafer 200 being moved into the processing chamber 201, and is aligned with the exhaust port 231a (described later) in a straight line. Nozzles 249a and 249c are positioned to clamp from both sides along a straight line L passing through the center of nozzle 249b and exhaust port 231a along the inner wall of the reaction tube 203 (outer periphery of the wafer 200). Straight line L also passes through the center of nozzle 249b and wafer 200. That is, nozzle 249c can also be positioned on the opposite side of nozzle 249a, sandwiching the straight line L. Nozzles 249a and 249c are symmetrically arranged about the straight line L as the axis of symmetry. Gas supply holes 250a to 250c are provided on the sides of nozzles 249a to 249c for supplying gas. Gas supply holes 250a to 250c are respectively opened in a manner that faces exhaust port 231a when viewed from above, and can supply gas to wafer 200. Multiple gas supply holes 250a to 250c are provided in the reaction tube 203 from bottom to top.

[0033] The precursor material (precursor gas) is supplied from the gas supply pipe 232a into the processing chamber 201 via MFC 241a, valve 243a, and nozzle 249a.

[0034] The raw material (raw material gas), which is one of the film-forming substances (film-forming gases), is supplied to the processing chamber 201 from the gas supply pipe 232b via MFC 241b, valve 243b, and nozzle 249b.

[0035] The reactant (reactant gas), which is one of the film-forming substances (film-forming gases) and also one of the reactants, is supplied to the processing chamber 201 from the gas supply pipe 232c via MFC 241c, valve 243c, and nozzle 249c.

[0036] The catalyst (catalyst gas), which is one of the film-forming substances (film-forming gases) and also one of the reactants, is supplied to the processing chamber 201 from the gas supply pipe 232d via MFC 241d, valve 243d, gas supply pipe 232a, and nozzle 249a.

[0037] The etchant (etching gas) is supplied to the processing chamber 201 from the gas supply pipe 232e via MFC 241e, valve 243e, gas supply pipe 232b, and nozzle 249b.

[0038] Inactive gases are supplied to the treatment chamber 201 from gas supply pipes 232f to 232h via MFCs 241f to 241h, valves 243f to 243h, gas supply pipes 232a to 232c, and nozzles 249a to 249c. The inactive gases function as purge gases, carrier gases, and dilution gases.

[0039] The precursor supply system mainly consists of gas supply pipe 232a, MFC 241a, and valve 243a. The raw material supply system mainly consists of gas supply pipe 232b, MFC 241b, and valve 243b. The reactant supply system mainly consists of gas supply pipe 232c, MFC 241c, and valve 243c. The catalyst supply system mainly consists of gas supply pipe 232d, MFC 241d, and valve 243d. The etchant supply system mainly consists of gas supply pipe 232e, MFC 241e, and valve 243e. The inactive gas supply system mainly consists of gas supply pipes 232f-232h, MFC 241f-241h, and valves 243f-243h. The raw material supply system and the reactant supply system, or all of them, are also referred to as the film-forming substance supply system. The reactant supply system and the catalyst supply system, either individually or in combination, are referred to as the reactant supply system.

[0040] One or all of the aforementioned supply systems can also be configured as an integrated supply system 248, which integrates valves 243a-243h, MFCs 241a-241h, etc. The integrated supply system 248 is configured to connect to each gas supply pipe 232a-232h, and the controller 121 (described later) controls the supply of various substances (various gases) into the gas supply pipes 232a-232h, i.e., the opening and closing of valves 243a-243h, and the flow regulation by MFCs 241a-241h. The integrated supply system 248 is configured as an integrated unit, either integral or modular, allowing for assembly and disassembly of the gas supply pipes 232a-232h, and enabling maintenance, replacement, and addition of the integrated supply system 248 at the unit level.

[0041] Below the side wall of the reaction tube 203, there is an exhaust port 231a for exhausting the atmosphere inside the processing chamber 201. Figure 2As shown, the exhaust port 231a, when viewed from above, is positioned opposite (facing) the nozzles 249a to 249c (gas supply holes 250a to 250c) while the wafer 200 is clamped. The exhaust port 231a can also be positioned from the lower part of the side wall of the reaction tube 203 along the upper part, i.e., along the wafer arrangement area. An exhaust pipe 231 is connected to the exhaust port 231a. A vacuum pump 246, serving as a vacuum exhaust device, is connected to the exhaust pipe 231 via a pressure sensor 245 (which acts as a pressure detector, or pressure detection unit) and an APC (Auto Pressure Controller) valve 244 (which acts as a pressure regulator, or pressure regulating unit). The APC valve 244 is configured to allow for vacuum exhaust and vacuum exhaust stop within the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operating. Furthermore, by adjusting the valve opening based on the pressure information detected by the pressure sensor 245 while the vacuum pump 246 is operating, the pressure within the processing chamber 201 can be adjusted. The exhaust system mainly consists of an exhaust pipe 231, an APC valve 244, and a pressure sensor 245. Alternatively, a vacuum pump 246 could be included in the exhaust system.

[0042] Below the manifold 209, a sealing cover 219, serving as a furnace opening cover, is provided to hermetically seal the lower 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. On the upper surface of the sealing cover 219, an O-ring 220b, serving as a sealing member, abuts against the lower end of the manifold 209. Below the sealing cover 219, a rotation mechanism 267 is provided for rotating the crystal boat 217 (described later). The rotation shaft 255 of the rotation mechanism 267 passes through the sealing cover 219 and is connected to the crystal boat 217. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the crystal boat 217. The sealing cover 219 is configured to move vertically upwards and downwards via a crystal boat lift 115, which serves as a lifting mechanism, located outside the reaction tube 203. The crystal boat lift 115 is configured as a transport device (transport mechanism) that moves the wafer 200 into and out of the processing chamber 201 by raising and lowering the sealing cover 219.

[0043] Below the manifold 209 is a gate 219s serving as a furnace opening cover. This gate 219s can hermetically seal the lower opening of the manifold 209 after the sealing cover 219 has been lowered and the crystal boat 217 has been removed from the processing chamber 201. The gate 219s is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220c, serving as a sealing component, is provided on the upper surface of the gate 219s, abutting against the lower end of the manifold 209. The opening and closing actions (lifting, rotating, etc.) of the gate 219s are controlled by a gate opening and closing mechanism 115s.

[0044] The crystal boat 217, serving as a substrate support, is configured to hold multiple wafers 200, for example 25 to 200, arranged horizontally with their centers aligned in a vertical direction and supported in a multi-layered manner, i.e., spaced apart. The crystal boat 217 is made of a heat-resistant material such as quartz or SiC. At the bottom of the crystal boat 217, a heat-insulating plate 218, also made of a heat-resistant material such as quartz or SiC, is supported in a multi-layered manner.

[0045] A temperature sensor 263, serving as a temperature detector, is installed inside the reaction tube 203. By adjusting the energizing state of the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature within the processing chamber 201 is adjusted to achieve the desired temperature distribution. The temperature sensor 263 is disposed along the inner wall of the reaction tube 203.

[0046] like Figure 3 As shown, the controller 121, serving as the control unit (control component), is configured as a computer comprising a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, storage device 121c, and I / O port 121d are configured to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122, such as a touch panel, is connected to the controller 121. Furthermore, an external storage device 123 can be connected to the controller 121.

[0047] The storage device 121c is composed of, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. The storage device 121c stores, in a readable manner, a control program that controls the operation of the substrate processing apparatus, and a process flow that describes the substrate processing steps and conditions, as described later. The process flow is a combination of steps in the substrate processing described later, executed by the controller 121, to obtain a predetermined result, and functions as a program. Hereinafter, the process flow, control program, etc., will also be referred to as a program. Furthermore, the process flow will be referred to simply as a process. In this specification, the term "program" is used in cases where only the process flow is included, cases where only the control program is included, or cases where both are included. RAM 121b is configured as a memory area (working area) that temporarily holds the program and data read by the CPU 121a.

[0048] I / O port 121d is connected to the aforementioned MFC241a to 241h, valves 243a to 243h, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotating mechanism 267, crystal boat elevator 115, gate opening and closing mechanism 115s, etc.

[0049] CPU 121a is configured to read and execute control programs from storage device 121c, and to read processes from storage device 121c based on inputs such as operation commands from input / output device 122. CPU 121a is configured to control the following actions according to the read processes: flow regulation of various substances (various gases) by MFC 241a to 241h, opening and closing of valves 243a to 243h, opening and closing of APC valve 244 and pressure regulation based on pressure sensor 245 using APC valve 244, starting and stopping of vacuum pump 246, temperature regulation of heater 207 based on temperature sensor 263, rotation and rotation speed regulation of crystal boat 217 using rotating mechanism 267, lifting and lowering of crystal boat 217 using crystal boat elevator 115, opening and closing of gate 219s using gate opening and closing mechanism 115s, etc.

[0050] The controller 121 is configured to install the aforementioned program stored in the external storage device 123 into a computer. The external storage device 123 includes, for example, a hard disk such as an HDD, an optical disk such as a CD, an optical disk such as an MO, a USB storage device, and a semiconductor storage device such as an SSD. The storage device 121c and the external storage device 123 are configured in the form of a recording medium that can be read by a computer. Hereinafter, they will also be referred to collectively as recording media. In this specification, the term "recording medium" is used in cases where only the storage device 121c is included, cases where only the external storage device 123 is included, or cases where both are included. It should be noted that providing the program to the computer may also be done without using the external storage device 123, but using communication means such as the Internet or a dedicated line.

[0051] (2) Substrate processing process

[0052] An example of a process sequence for forming a film within a recess in the surface of a wafer 200, which serves as a substrate, is described above, used as a step in the manufacturing process of a semiconductor device. This process involves filling the recesses in the wafer 200, which is itself a substrate. The main method used is... Figure 4 , Figure 5 (a)~ Figure 5 (d) will be explained below. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

[0053] It should be noted that, as Figure 5 As shown in (a), a recess is provided on the surface of wafer 200, wherein the upper surface and side surface of the recess are made of a first material containing a first element, the bottom surface is made of a second material containing a second element different from the first element, and the depth direction is a direction parallel to the surface of wafer 200 (lateral). Figure 5 Example (a) shows the following: the first element is silicon (Si), the second element is germanium (Ge), the first material is silicon (Si), and the second material is silicon-germanium (SiGe). That is, in this example, the second material contains both the first and the second element. Furthermore, the wafer 200 is composed of single-crystal Si. That is, the wafer 200 contains the first element.

[0054] More specifically, a stacked structure of alternating layers of a second material (SiGe) and a first material (Si) is provided on the surface of the wafer 200, and an insulating film is provided on this stacked structure. That is, a stacked structure of alternating layers of silicon-germanium (SiGe) films and silicon (Si) films is provided on the surface of the wafer 200, and an insulating film is provided on this stacked structure. By removing a portion of the SiGe film portion from the sidewall of the SiGe-Si film stacked structure, a recess is formed on the sidewall of the stacked structure. The upper and side surfaces of the recess are made of the first material (Si), the bottom surface is made of the second material (SiGe), and the depth direction is parallel to the surface of the wafer 200 (lateral direction). It should be noted that in this specification, as... Figure 5 As shown in (a), the portion of the recess made of the second material (SiGe) is called the bottom surface. Based on this, the portion of the recess made of the first material (Si) that is in contact with the bottom surface and is perpendicular to the bottom surface is called the side surface. The portion of the recess made of the first material (Si) that is not in contact with the bottom surface and is parallel to the bottom surface is called the top surface.

[0055] Figure 4 The processing sequence shown includes the following steps: Step A, supplying a precursor material to a wafer 200 having recesses on its surface, wherein the upper surface and side surfaces of the recesses are made of a first material containing a first element, and the bottom surface is made of a second material containing a second element different from the first element, thereby adsorbing at least a portion of the molecular structure of the precursor material onto the surface of the first material of the recess, and forming a film-forming inhibition layer on the surface of the first material; and Step B, supplying a film-forming material to the wafer 200 having the film-forming inhibition layer formed on the surface of the first material, thereby causing a film to grow on the surface of the second material of the recess.

[0056] like Figure 4As shown, in step B, the following steps will be performed cyclically a specified number of times, not simultaneously:

[0057] Step B1, supplying raw materials to wafer 200 as film-forming substances; and,

[0058] Step B2 involves supplying an oxidant, which is a reactant, to the wafer 200 as a film-forming substance.

[0059] Thus, the membrane grows from the bottom of the concave portion, growing upwards within the concave portion, and is used to fill the concave portion.

[0060] At this point, in at least either step B1 or step B2, a catalyst may be supplied to the wafer 200 as a film-forming substance. Figure 4 The following example is shown: In each of steps B1 and B2, a catalyst is also supplied to the wafer 200 as a film-forming substance.

[0061] in addition, Figure 4 The processing sequence shown also includes the following step C: Before step A, an oxidizing agent as a reactant is supplied to wafer 200 to oxidize the surface of the first material, thereby forming hydroxyl end caps on the surface of the first material. At this time, the surface of the second material is also oxidized, and hydroxyl end caps are also formed on the surface of the second material.

[0062] in addition, Figure 4 The processing sequence shown also includes step D: by heating and annealing (hereinafter also referred to as ANL) the wafer 200 after step C and before step A, the oxide formed on the surface of the second material sublimates, thereby removing the hydroxyl end caps formed on the surface of the second material. At this time, the hydroxyl end caps formed on the surface of the first material remain, while the hydroxyl end caps formed on the surface of the second material are removed. Thus, hydroxyl end caps are formed on the surface of the first material before step A, and no hydroxyl end caps are formed on the surface of the second material before step A, or a much smaller amount of hydroxyl end caps are formed compared to the amount of hydroxyl end caps on the surface of the first material. Hereinafter, hydroxyl end caps will also be referred to as OH end caps.

[0063] in addition, Figure 4 The processing sequence shown also includes step E: before step C, etchant is supplied to wafer 200 to remove the natural oxide film on the surfaces of the first material and the second material.

[0064] in addition, Figure 4 The processing sequence shown also includes step F, that is, after step B, the wafer 200 is heated to perform heat treatment, thereby performing post-processing on the film formed by filling the recess, that is, performing post-treatment (hereinafter also referred to as PT).

[0065] It should be noted that, in this method, the following example is used for illustration: the first element is Si, the second element is Ge, the first material is Si, the second material is SiGe, and in step B, as a film, a silicon oxide carbide film (SiOC film), which is one of the films containing silicon (Si), oxygen (O), and carbon (C), or a silicon oxide film (SiO film), which is one of the films containing silicon (Si) and oxygen (O), is grown.

[0066] For convenience, the above processing sequence is sometimes shown in this specification as follows. The same wording is also used in the following descriptions of variations and other methods.

[0067] Etching agent → Oxidizing agent → ANL → Precursor → (Raw material + Catalyst → Oxidizing agent + Catalyst) × n → PT

[0068] In this specification, the term "wafer" is used to refer to the wafer itself, or to a laminate of the wafer and a specified layer or film formed on its surface. The term "surface of the wafer" is used to refer to the surface of the wafer itself, or to the surface of a specified layer, etc., formed on the wafer. The phrase "forming a specified layer on the wafer" includes forming the specified layer directly on the surface of the wafer itself, or forming the specified layer on top of a layer, etc., formed on the wafer. The term "substrate" is used in the same way as "wafer."

[0069] (Wafer filling and crystal boat loading)

[0070] After multiple wafers 200 are loaded into the crystal boat 217 (wafer filling), the gate 219s is moved by the gate opening and closing mechanism 115s, opening the lower end opening of the manifold 209 (gate opening). Then, as... Figure 1 As shown, a crystal boat 217 supporting multiple wafers 200 is lifted by a crystal boat elevator 115 and moved into the processing chamber 201 (crystal boat loading). In this state, the sealing cap 219 seals the lower end of the manifold 209 by means of an O-ring 220b.

[0071] (Pressure and temperature regulation)

[0072] Vacuum pump 246 performs vacuum venting (pressure reduction venting) to bring the processing chamber 201, where the wafer 200 is located, to the desired pressure (vacuum level). The pressure within the processing chamber 201 is measured by pressure sensor 245, and the APC valve 244 is controlled based on this measured pressure information. Additionally, heater 207 heats the wafer 200 within the processing chamber 201 to the desired processing temperature. The energizing state of heater 207 is controlled based on temperature information detected by temperature sensor 263 to achieve the desired temperature distribution within the processing chamber 201. Furthermore, rotation of the wafer 200 is initiated using rotation mechanism 267. Venting of the processing chamber 201, heating of the wafer 200, and rotation are all performed continuously, at least until the processing of the wafer 200 is completed.

[0073] (Step E: Remove the natural oxide film)

[0074] Then, etchant is supplied to the wafer 200.

[0075] Specifically, valve 243e is opened, allowing etchant (etching gas) to flow into gas supply pipe 232e. The etchant flow rate is regulated by MFC 241e, and it is supplied to processing chamber 201 via gas supply pipe 232b and nozzle 249b, and exhausted from exhaust port 231a. At this time, etchant is supplied to wafer 200 from the side (etchant supply). At this time, valves 243f to 243h can be opened, supplying inactive gas into processing chamber 201 via nozzles 249a to 249c respectively.

[0076] By supplying an etchant to the wafer 200 under the processing conditions described later, the native oxide film formed on the surface of the wafer 200 can be removed. That is, the native oxide films on the surfaces of the first material and the second material on the surface of the wafer 200 can be removed. Specifically, the native oxide film on the recessed surface provided on the surface of the wafer 200 can be removed, which is formed such that its upper and side surfaces are made of the first material (Si), its bottom surface is made of the second material (SiGe), and its depth direction is a direction parallel to the surface of the wafer 200 (lateral direction).

[0077] After removing the natural oxide film formed on the surface of wafer 200, valve 243e is closed to stop the supply of etchant to the processing chamber 201. Then, a vacuum is applied to the processing chamber 201 to remove any gaseous substances remaining within it. At this time, valves 243f to 243h are opened, and inactive gas is supplied to the processing chamber 201 via nozzles 249a to 249c. The inactive gas supplied by nozzles 249a to 249c acts as a purging gas, thereby purging the processing chamber 201.

[0078] Examples of processing conditions in the supply of etchant can be shown as follows:

[0079] Processing temperature: room temperature (25℃) to 200℃, preferably 50 to 150℃.

[0080] Processing pressure: 10~13332Pa, 20~1333Pa

[0081] Etching agent supply flow rate: 0.5–5 slm, preferably 0.5–2 slm

[0082] Etching agent supply time: 1–120 minutes, preferably 1–60 minutes

[0083] Inactive gas supply flow rate (per gas supply pipe): 0–20 slm.

[0084] Examples of treatment conditions during purging include:

[0085] Processing temperature: Room temperature (25℃) to 500℃

[0086] Processing pressure: 1~30Pa

[0087] Inactive gas supply flow rate (per gas supply pipe): 0.5–20 slm

[0088] Inactive gas supply time: 1 to 120 seconds, preferably 1 to 60 seconds.

[0089] It should be noted that the numerical ranges expressed in this specification, such as "25~200℃", refer to the lower and upper limits, which are included within the range. Therefore, for example, "25~200℃" means "above 25℃ and below 200℃". The same applies to other numerical ranges. Furthermore, the processing temperature in this specification refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201, and the processing pressure refers to the pressure inside the processing chamber 201. Additionally, the gas supply flow rate of 0 slm indicates that the gas is not supplied. These same principles apply in the following descriptions.

[0090] For example, fluorine (F) gas can be used as an etchant. Examples of F-containing gases include hydrogen fluoride (HF) gas and fluorine (F2) gas. In addition to these, aqueous solutions of HF can also be used as etchants. That is, the etchant can be a gaseous substance or a liquid substance. Furthermore, the etchant can be a liquid substance such as a mist. One or more of these can be used as an etchant.

[0091] As inert gases, rare gases such as nitrogen (N2), argon (Ar), helium (He), neon (Ne), and xenon (Xe) can be used. This point also applies to the steps described later. More than one of these gases can be used as an inert gas.

[0092] (Step C: Oxidation)

[0093] Then, an oxidant (oxidizing gas) is supplied to the wafer 200 as a reactant.

[0094] Specifically, valve 243c is opened, allowing an oxidant, one of the reactants, to flow into gas supply pipe 232c as a reactant. The oxidant is regulated by MFC 241c and supplied to processing chamber 201 via nozzle 249c, and exhausted from exhaust port 231a. At this time, oxidant is supplied to wafer 200 from the side of wafer 200 (oxidant supply). At this time, valve 243d can be opened, allowing a catalyst to flow into gas supply pipe 232d. In this case, the catalyst is regulated by MFC 241d and supplied to processing chamber 201 via gas supply pipe 232a and nozzle 249a, mixing with the oxidant in processing chamber 201, and exhausted from exhaust port 231a. At this time, a mixture of catalyst and oxidant (mixed gas) is supplied to wafer 200 from the side of wafer 200. Additionally, valves 243f to 243h can be opened at this time, supplying inactive gases to processing chamber 201 via nozzles 249a to 249c respectively.

[0095] By supplying an oxidant, or a mixture of an oxidant and a catalyst, to the wafer 200 under the processing conditions described later, the surface of the first material (Si) on the surface of the wafer 200 after the natural oxide film has been removed can be oxidized, thereby forming OH caps on the surface of the first material (Si). An oxide film (oxide) such as a silicon oxide film (SiO film) is formed on the surface of the first material (Si), and OH caps are formed on its surface. It should be noted that by supplying the wafer 200 with a mixture of an oxidant and a catalyst, the oxidation rate can be increased at low temperatures. However, in cases where a reduction in the oxidation rate is required, or where the oxidation rate needs to be controlled by temperature, the supply of the catalyst can be omitted.

[0096] At this time, the surface of the second material (SiGe) on the wafer 200 is also oxidized, and OH caps are formed on the surface of the second material (SiGe). On the surface of the second material (SiGe), there are oxide films such as germanium oxide film (GeO film) and silicon germanium oxide film (SiGeO film), and OH caps are formed on their surfaces.

[0097] After forming OH caps on the surface of the first material (Si) on the wafer 200, valve 243d is closed to stop the supply of oxidant to the processing chamber 201. At this time, while the catalyst is being supplied simultaneously, valve 243d is also closed, stopping the supply of catalyst to the processing chamber 201. Then, using the same processing steps and conditions as in step E, gaseous substances remaining in the processing chamber 201 are removed from the processing chamber 201 (purging).

[0098] Examples of processing conditions in the supply of oxidant can be shown.

[0099] Processing temperature: room temperature (25℃) to 500℃, preferably room temperature to 300℃

[0100] Processing pressure: 1–101325 Pa, preferably 1–13332 Pa

[0101] Oxidant supply flow rate: 0.1–10 slm, preferably 0.5–5 slm

[0102] Oxidant supply time: 1–120 minutes, preferably 1–60 minutes

[0103] Catalyst supply flow rate: 0–10000 sccm

[0104] Inactive gas supply flow rate (per gas supply pipe): 0–20 slm.

[0105] As an oxidant, for example, oxygen-containing (O) gas or a gas containing both oxygen (O) and hydrogen (H) can be used. As an O-containing gas, for example, oxygen (O2), ozone (O3), nitrous oxide (N2O), nitric oxide (NO), nitrogen dioxide (NO2), carbon monoxide (CO), carbon dioxide (CO2), etc., can be used. As a gas containing both O and H, for example, water vapor (H2O), hydrogen peroxide (H2O2), hydrogen (H2) gas + oxygen (O2), H2 gas + ozone (O3), etc., can also be used. It should be noted that gases containing both O and H are also considered O-containing gases. In addition to these, cleaning solutions, such as those containing ammonia, hydrogen peroxide aqueous solution, and pure water, can also be used as oxidants. That is, oxidation can be performed by APM cleaning. In this case, oxidation can be performed by exposing the wafer 200 to the cleaning solution. Thus, the oxidant can be a gaseous substance or a liquid substance. In addition, the oxidant can be a liquid substance such as a mist. More than one of these can be used as the oxidant.

[0106] As a catalyst, for example, an amine gas containing carbon (C), nitrogen (N), and hydrogen (H) can be used. Examples of amine gases that can be used include pyridine (C5H5N), aminopyridine (C5H6N2), methylpyridine (C6H7N), dimethylpyridine (C7H9N), and piperazine (C4H2N). 10 N2 gas, piperidine (C5H) 11 Cyclic amine gases such as N, and chain amine gases such as triethylamine ((C2H5)3N, abbreviated as TEA) and diethylamine ((C2H5)2NH, abbreviated as DEA). This aspect also applies to step B described later.

[0107] (Step D: ANL)

[0108] After forming OH end caps on the surface of the first material (Si), the processing chamber 201 is purged as described above. Simultaneously with this purging, the wafer 200 is heated and annealed. It should be noted that, as mentioned earlier, the heating of the wafer 200 continues at least until the processing of the wafer 200 is completed; therefore, annealing begins once the supply of oxidant and catalyst is stopped.

[0109] By annealing the wafer 200 under the processing conditions described later, oxides such as GeO formed on the surface of the second material (SiGe) can be sublimated, thereby removing the OH end caps formed on the surface of the second material (SiGe).

[0110] At this time, not only the second material (SiGe) but also the first material (Si) is heated. The oxide film, such as the SiO film, formed on the surface of the first material (Si) has strong Si-O bonds, and therefore does not sublimate under the processing conditions described later. That is, even if annealing is performed, the OH end caps formed on the surface of the first material (Si) can be maintained and not removed.

[0111] Thus, in the annealing process in step D, the oxide film such as SiO formed on the surface of the first material (Si) can be retained (maintained), while the oxides such as GeO formed on the surface of the second material (SiGe) can be removed. That is, in the annealing process in step D, the OH end caps formed on the surface of the first material (Si) can be retained (maintained), while the OH end caps formed on the surface of the second material (SiGe) can be removed. It should be noted that there is also a situation where not all the OH end caps formed on the surface of the second material (SiGe) are removed, and a very small portion remains.

[0112] Therefore, the surface of the first material (Si) before step A is in a state where OH end caps are formed on its surface. Conversely, the surface of the second material (SiGe) before step A is in a state where OH end caps are not formed on its surface, or in a state where a much smaller amount of OH end caps are formed on its surface compared to the amount of OH end caps on the surface of the first material (Si). That is, the amount (density, concentration) of OH end caps on the surface of the first material (Si) before step A is greater than (higher than) the amount (density, concentration) of OH end caps on the surface of the second material (SiGe).

[0113] Examples of processing conditions in annealing (ANL) can be shown.

[0114] Processing temperature: 100–500℃, preferably 100–300℃

[0115] Processing pressure: 1–13332 Pa, preferably 1–1333 Pa

[0116] Inactive gas supply flow rate (per gas supply pipe): 0–20 slm

[0117] Annealing time: 1 to 120 minutes, preferably 1 to 60 minutes.

[0118] (Step A: Formation of a film-forming inhibition layer)

[0119] Then, the precursor material is supplied to the chip 200.

[0120] Specifically, valve 243a is opened, allowing precursor material to flow into gas supply pipe 232a. The precursor material is regulated by MFC 241a, supplied to processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, precursor material is supplied to wafer 200 from the side (precursor material supply). At this time, valves 243f to 243h can be opened, supplying inactive gas into processing chamber 201 via nozzles 249a to 249c respectively.

[0121] By supplying a precursor material to the wafer 200 under the processing conditions described later, at least a portion of the molecular structure constituting the precursor material's molecules can be selectively (preferably) adsorbed onto the surface of the first material (Si) of the first material (Si) and the second material (SiGe) in the recesses of the wafer 200 surface, thereby selectively (preferably) forming a film-forming inhibition layer on the surface of the first material (Si). Specifically, at least a portion of the molecular structure constituting the precursor material's molecules can be inhibited from adsorbing onto the surface of the second material (SiGe), while simultaneously, the OH groups that cap the surface of the first material (Si) react with the precursor material, causing at least a portion of the molecular structure constituting the precursor material's molecules to be selectively adsorbed onto the surface of the first material (Si). Thus, the surface of the first material (Si) can be capped using at least a portion of the molecular structure constituting the precursor material's molecules. Examples of at least a portion of the molecular structure constituting the precursor material's molecules include trimethylsilyl (Si-Me3) and triethylsilyl (Si-Et3). In these cases, trimethylsilyl or triethylsilyl Si is adsorbed onto the surface of the first material (Si), and the outermost surface of the first material (Si) is capped by alkyl groups such as methyl or ethyl. At least a portion of the molecular structure of the precursor molecules capped on the surface of the first material (Si), such as alkyl groups (alkylsilyl) such as methyl (trimethylsilyl) or ethyl (triethylsilyl), prevents the adsorption of the raw material onto the surface of the first material (Si) during the film-forming process (selective growth) described later. This acts as a film-forming barrier layer (film-forming inhibition layer), i.e., an inhibitor, that hinders the film-forming reaction on the surface of the first material (Si).

[0122] It should be noted that in this step, sometimes at least a portion of the molecular structure constituting the precursor substance is adsorbed on a portion of the surface of the second material (SiGe), but the amount adsorbed is very small, while the amount adsorbed onto the surface of the first material (Si) overwhelmingly increases. This selective (preferred) adsorption is achieved because the processing conditions in this step are set such that the precursor substance does not undergo gas-phase decomposition within the processing chamber 201. Furthermore, this is because the surface of the first material (Si) is capped with OH over its entire area, while most of the surface of the second material (SiGe) is not capped with OH. In this step, since the precursor substance does not undergo gas-phase decomposition within the processing chamber 201, at least a portion of the molecular structure constituting the precursor substance is not multiple-deposited on both the surfaces of the first material (Si) and the second material (SiGe). Instead, at least a portion of the molecular structure constituting the precursor substance is selectively adsorbed on the surface of the first material (Si), thereby selectively capping the surface of the first material (Si) with at least a portion of the molecular structure constituting the precursor substance.

[0123] After selectively forming a film-forming inhibition layer on the surface of the first material (Si), valve 243a is closed to stop the supply of precursor material to the processing chamber 201. Then, using the same processing steps and conditions as in step E, gaseous substances and the like remaining in the processing chamber 201 are removed from the processing chamber 201 (purging).

[0124] Examples of processing conditions in the supply of precursor substances can be shown.

[0125] Processing temperature: room temperature (25℃) to 500℃, preferably room temperature to 250℃

[0126] Processing pressure: 5~1000Pa

[0127] Precursor supply flow rate: 1–3000 sccm, preferably 1–500 sccm

[0128] Precursor supply time: 1 second to 120 minutes, preferably 30 seconds to 60 minutes

[0129] Inactive gas supply flow rate (per gas supply pipe): 0–20 slm.

[0130] As a precursor, for example, a substance containing one or more atoms directly bonded to the first functional group and the second functional group can be used. The first functional group in the precursor is preferably a functional group capable of chemically adsorbing the precursor onto an adsorption site (e.g., OH-terminated) on the surface of the first material (Si). Preferably, the first functional group contains an amino group, and more preferably, a substituted amino group. When the precursor contains an amino group (preferably a substituted amino group), a greater amount of the precursor is chemically adsorbed onto the surface of the first material (Si). Especially from the viewpoint of adsorption to the surface of the first material (Si), it is preferable that the first functional group of the precursor is entirely a substituted amino group.

[0131] The substituents in the substituted amino group are preferably alkyl groups, more preferably alkyl groups having 1 to 5 carbon atoms, and particularly preferably alkyl groups having 1 to 4 carbon atoms. The alkyl group in the substituted amino group can be linear or branched. Specifically, examples of alkyl groups in the substituted amino group include methyl, ethyl, n-propyl, n-butyl, isopropyl, isobutyl, sec-butyl, and tert-butyl. The number of substituents in the substituted amino group is 1 or 2, preferably 2. When the number of substituents in the substituted amino group is 2, the two substituents can be the same or different.

[0132] The number of first functional groups in the precursor is preferably 2 or less, more preferably 1. It should be noted that if the precursor has multiple first functional groups, they may be the same or different.

[0133] The second functional group in the precursor is preferably a functional group capable of modifying the outermost surface of the first material (Si) into a film-forming barrier region. The second functional group is preferably a chemically stable functional group, more preferably a hydrocarbon group. As a hydrocarbon group, it can be an aliphatic hydrocarbon group such as alkyl, alkenyl, or alkynyl, or an aromatic hydrocarbon group. Among these, alkyl groups are preferred. Especially from the viewpoint of high chemical stability, it is preferable that the second functional group of the precursor is always alkyl.

[0134] The alkyl group serving as the second functional group is more preferably an alkyl group having 1 to 5 carbon atoms, and particularly preferably an alkyl group having 1 to 4 carbon atoms. The alkyl group comprising the substituted amino group can be straight-chain or branched. Examples of alkyl groups comprising the substituted amino group include methyl, ethyl, n-propyl, n-butyl, isopropyl, isobutyl, sec-butyl, tert-butyl, etc.

[0135] The number of second functional groups in the precursor substance can be an integer of 1 or more. When the number of first functional groups in the precursor substance is 1, the number of second functional groups in the precursor substance is preferably 3. Furthermore, when the number of first functional groups in the precursor substance is 2, the number of second functional groups in the precursor substance is preferably 2. The multiple second functional groups possessed by the precursor substance can be the same or different.

[0136] In the precursor material, atoms that directly bond to the first and second functional groups can include carbon (C) atoms, silicon (Si) atoms, germanium (Ge) atoms, and tetravalent metal atoms. Here, tetravalent metal atoms can include titanium (Ti) atoms, zirconium (Zr) atoms, hafnium (Hf) atoms, molybdenum (Mo) atoms, and tungsten (W) atoms. It should be noted that the atoms directly bonded to the first and second functional groups can be not only tetravalent metal atoms, but also metal atoms capable of bonding to four or more ligands. In this case, increasing the number of second functional groups can enhance the inhibitory effect.

[0137] Among these, C atoms, Si atoms, and Ge atoms are preferred as atoms that directly bond to the first and second functional groups. This is because using any one of C, Si, or Ge atoms as atoms that directly bond to the first and second functional groups allows for at least one of the following properties: high adsorption capacity of the precursor material to the surface of the first material (Si) and high chemical stability of the precursor material residues adsorbed on the surface of the first material (Si). Among these, Si atoms are more preferred as atoms that directly bond to the first and second functional groups. This is because using Si atoms as atoms allows for a balanced and good combination of both the high adsorption capacity of the precursor material to the surface of the first material (Si) and the high chemical stability of the precursor material residues adsorbed on the surface of the first material (Si). As mentioned above, atoms directly bonded to the first and second functional groups can also be bonded to hydrogen (H) atoms or the third functional group.

[0138] The third functional group, which is bonded to an atom directly bonded to the first and second functional groups, can be any functional group other than those described above that constitute the first and second functional groups. Examples of third functional groups include functional groups formed by appropriately combining two or more of the following: C atom, Si atom, Ge atom, tetravalent metal atom, metal atom capable of bonding with four or more ligands, O atom, nitrogen (N) atom, and H atom.

[0139] The precursor substance contains one or more atoms whose first and second functional groups are directly bonded, or it may contain two or more atoms whose first and second functional groups are directly bonded. For convenience, the atom whose first and second functional groups are directly bonded will be referred to as atom X.

[0140] The precursor material preferably has a structure comprising tetravalent atoms directly bonded to the first and second functional groups. More preferably, the precursor material has a structure comprising tetravalent atoms directly bonded only to the first and second functional groups. Particularly preferably, the precursor material has a structure comprising a single Si atom directly bonded only to the first and second functional groups. That is, the precursor material particularly preferably has a structure in which only the first and second functional groups are directly bonded to the Si atom, which serves as the central atom.

[0141] The precursor material preferably has a structure containing one amino group per molecule. More preferably, the precursor material has a structure containing one amino group and at least one alkyl group per molecule. Even more preferably, the precursor material has a structure containing one amino group and three alkyl groups per molecule. Furthermore, the precursor material preferably has a structure in which one amino group is bonded to a Si atom serving as the central atom. More preferably, the precursor material has a structure in which one amino group and at least one alkyl group are bonded to a Si atom serving as the central atom. Even more preferably, the precursor material has a structure in which one amino group and three alkyl groups are bonded to a Si atom serving as the central atom. It should be noted that, as mentioned above, the amino group is preferably a substituted amino group. Regarding the substituents in the substituted amino group, as described above...

[0142] As a precursor, for example, a compound represented by the following formula 1 is preferred.

[0143] Equation 1: [R] 1 ]n 1 -(X)-[R 2 ]m 1

[0144] In Equation 1, R 1 R represents the first functional group that is directly bonded to X. 2 This represents the second functional group or H atom directly bonded to X, where X represents a tetravalent atom selected from the group consisting of C, Si, Ge, and tetravalent metal atoms. 1 Indicates 1 or 2, m 1 It indicates 2 or 3.

[0145] R 1 The meaning of the first functional group is the same as that of the first functional group mentioned above, and the preferred examples are also the same. 1 When the value is 2, there are 2 R's. 1 They can be the same or different. R 2 The second functional group referred to here has the same meaning as the second functional group mentioned above, and the preferred examples are also the same. 1 When it is 2 or 3, there are 2 or 3 Rs. 2 In this structure, one or two atoms can be hydrogen (H) atoms, with the remainder being secondary functional groups; alternatively, all atoms can be secondary functional groups. There can be two or three hydrogen (R) atoms. 2 When all atoms have a second functional group, these second functional groups can be the same or different. For the tetravalent atom represented by X, Si atoms are preferred. For n... 2 , preferred 1. As m 2 , Option 3 is preferred.

[0146] As precursors, for example, (dimethylamino)trimethylsilane ((CH3)2NSi(CH3)3, abbreviated as DMATMS), (diethylamino)triethylsilane ((C2H5)2NSi(C2H5)3, abbreviated as DEATES), (dimethylamino)triethylsilane ((CH3)2NSi(C2H5)3, abbreviated as DMATES), (diethylamino)trimethylsilane ((C2H5)2NSi(CH3)3, abbreviated as DEATMS), (trimethylsilyl)amine ((CH3)3SiNH2, abbreviated as TMSA), (triethylsilyl)amine ((C2H5)3SiNH2, abbreviated as TESA), (dimethylamino)silane ((CH3)2NSiH3, abbreviated as DMAS), (diethylamino)silane ((C2H5)2NSiH3, abbreviated as DEAS), etc.

[0147] Alternatively, as precursors, for example, bis(dimethylamino)dimethylsilane ([(CH3)2N]2Si(CH3)2, abbreviated as BDMADMS), bis(diethylamino)diethylsilane ([(C2H5)2N]2Si(C2H5)2, abbreviated as BDEADES), bis(dimethylamino)diethylsilane ([(CH3)2N]2Si(C2H5)2, abbreviated as BDMADES), bis(diethyl ... ethylamino)dimethylsilane ([(C2H5)2N]2Si(CH3)2, abbreviated as BDEADMS), bis(dimethylamino)silane ([(CH3)2N]2SiH2, abbreviated as BDMAS), bis(dimethylamino)ethane ([(CH3)2N(CH3)2Si]2C2H6, abbreviated as BDMADMSE), bis(dipropylamino)silane ([(C3H7)2N]2SiH2) (Abbreviations: BDPAS), bis(dipropylamino)dimethylsilane ([(C3H7)2N]2Si(CH3)2, abbreviated as BDPADMS), bis(dipropylamino)diethylsilane ([(C3H7)2N]2Si(C2H5)2, abbreviated as BDPADES), (dimethylsilyl)diamine ((CH3)2Si(NH2)2, abbreviated as DMSDA), (diethylsilyl)diamine ((C2H5) 2Si(NH2)2 (abbreviated as DESDA), (dipropylsilyl)diamine ((C3H7)2Si(NH2)2 (abbreviated as DESDA), bis(dimethylaminodimethylsilyl)methane ([(CH3)2N(CH3)2Si]2CH2 (abbreviated as BDMADMSM), bis(dimethylamino)tetramethyldisilane ([(CH3)2N]2(CH3)4Si2 (abbreviated as BDMATMDS), etc.

[0148] These are all organic compounds with an amino group and an alkyl group directly bonded to Si. These compounds can also be called aminoalkyl compounds or alkylamino compounds. It should be noted that the precursor can be a gas or a liquid. Additionally, the precursor can be a liquid such as a mist. More than one of these can be used as a precursor.

[0149] (Step B: Film Formation Treatment (Selective Growth))

[0150] Then, the following steps B1 and B2 are performed sequentially. It should be noted that in these steps, the output power of the heater 207 is adjusted to maintain the temperature of the wafer 200 below the temperature of the wafer 200 in step A, preferably maintaining it at a temperature lower than that of the wafer 200 in step A.

[0151] [Step B1]

[0152] In this step, raw materials (raw material gas) and catalyst (catalyst gas) are supplied to the wafer 200, i.e. the first material (Si), which has selectively formed a film-forming inhibition layer on its surface in the processing chamber 201, as film-forming substances.

[0153] Specifically, valves 243b and 243d are opened, allowing raw materials to flow into gas supply pipe 232b and catalyst to flow into gas supply pipe 232d, respectively. The flow rates of the raw materials and catalyst are regulated by MFCs 241b and 241d, and supplied to the processing chamber 201 via nozzles 249b and 249a. The mixture is then exhausted through exhaust port 231a. At this time, raw materials and catalyst (raw materials + catalyst supply) are supplied to the wafer 200. Then, valves 243f to 243h can be opened, supplying inactive gases to the processing chamber 201 via nozzles 249a to 249c.

[0154] By supplying raw materials and a catalyst to the wafer 200 under the processing conditions described later, it is possible to suppress the chemical adsorption of at least a portion of the molecular structure constituting the raw material molecules onto the surface of the first material (Si), while simultaneously enabling at least a portion of the molecular structure constituting the raw material molecules to selectively (preferably) chemically adsorb onto the surface of the second material (SiGe). Thus, a first layer is selectively (preferably) formed on the surface of the second material (SiGe). The first layer contains at least a portion of the molecular structure constituting the raw material molecules; that is, the first layer contains at least a portion of the atoms constituting the raw material.

[0155] In this step, by supplying the catalyst together with the raw materials, the above-mentioned reaction can be carried out in a non-plasma atmosphere and at a low temperature as described later. Thus, by forming the first layer in a non-plasma atmosphere and at a low temperature as described later, the molecules and atoms constituting the film-forming inhibition layer formed on the surface of the first material (Si) are maintained and do not disappear (detach) from the surface of the first material (Si).

[0156] Furthermore, by forming the first layer under a non-plasma atmosphere and at such low temperature conditions as described later, it is possible to prevent thermal decomposition (gas phase decomposition), i.e. self-decomposition, of the raw material in the processing chamber 201, suppress the multiple deposition of at least a portion of the molecular structure constituting the raw material on the surfaces of the first material (Si) and the second material (SiGe), and enable the raw material to be selectively adsorbed on the surface of the second material (SiGe).

[0157] After the first layer is selectively formed on the surface of the second material (SiGe), valves 243b and 243d are closed to stop the supply of raw materials and catalyst to the processing chamber 201. Then, using the same processing steps and conditions as in step E, residual gases in the processing chamber 201 are removed (purged). It should be noted that the processing temperature during purging in this step is preferably the same as the processing temperature during the supply of raw materials and catalyst.

[0158] Examples of processing conditions in the supply of raw materials and catalysts can be shown.

[0159] Processing temperature: room temperature (25℃) to 120℃, preferably room temperature to 90℃

[0160] Processing pressure: 133~1333Pa

[0161] Raw material supply flow rate: 1-2000 sccm

[0162] Catalyst supply flow rate: 1–2000 sccm

[0163] Inactive gas supply flow rate (per gas supply tube): 0–20000 sccm

[0164] Gas supply time: 1 to 60 seconds.

[0165] It should be noted that during the formation of the first layer in this step, at least a portion of the molecular structure constituting the raw material molecules may adsorb onto a portion of the surface of the first material (Si), but the amount adsorbed is extremely small, far less than the amount adsorbed onto the surface of the second material (SiGe) by at least a portion of the molecular structure constituting the raw material molecules. This selective (preferred) adsorption is achieved because the processing conditions in this step are set to the low temperature conditions described above, and under conditions where the raw material does not undergo gas-phase decomposition within the processing chamber 201. Furthermore, this is because, in contrast to the formation of a film-forming inhibition layer over the entire surface area of ​​the first material (Si), no film-forming inhibition layer is formed over most of the surface area of ​​the second material (SiGe).

[0166] As a raw material, for example, gases containing Si and halogens can be used. Halogens include chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc. The Si-containing and halogen-containing gases preferably contain halogens in the form of chemical bonds between Si and the halogen. The Si-containing and halogen-containing gases may also contain carbon (C), in which case C is preferably contained in the form of Si-C bonds. As a Si-containing and halogen-containing gas, for example, silane-based gases containing Si, Cl, and alkylene groups, having Si-C bonds, i.e., alkylchlorosilane-based gases, can be used. Alkylenes include methylene, ethylene, propylene, butylene, etc. Alkylchlorosilane-based gases preferably contain Cl in the form of Si-Cl bonds and C in the form of Si-C bonds.

[0167] As gases containing Si and halogens, for example, alkylchlorosilane gases such as bis(trichlorosilyl)methane ((SiCl3)2CH2, abbreviated as BTCSM) gas, 1,2-bis(trichlorosilyl)ethane ((SiCl3)2C2H4, abbreviated as BTCSE) gas, alkylchlorosilane gases such as 1,1,2,2-tetrachloro-1,2-dimethyldisilane ((CH3)2Si2Cl4, abbreviated as TCDMDS) gas, 1,2-dichloro-1,1,2,2-tetramethyldisilane ((CH3)4Si2Cl2, abbreviated as DCTMDS) gas, and gases containing cyclic structures composed of Si and C and halogens such as 1,1,3,3-tetrachloro-1,3-disilocyclobutane (C2H4Cl4Si2, abbreviated as TCDSCB) gas can be used. Alternatively, inorganic chlorosilane gases such as tetrachlorosilane (SiCl4, abbreviated as STC), hexachlorodisilane (Si2Cl6, abbreviated as HCDS), and octachlorotrisilane (Si3Cl8, abbreviated as OCTS) can be used as raw materials containing Si and halogens. One or more of these can be used as raw materials. It should be noted that the raw materials can be gaseous or liquid. Furthermore, the raw materials can be liquid substances such as mists.

[0168] Alternatively, as raw materials, tetra(dimethylamino)silane (Si[N(CH3)2]4, abbreviated as 4DMAS), tri(dimethylamino)silane (Si[N(CH3)2]3H, abbreviated as 3DMAS), bis(diethylamino)silane (Si[N(C2H5)2]2H2, abbreviated as BDEAS), bis(tert-butylamino)silane (SiH2[NH(C4H9)]2, abbreviated as BTBAS), and (diisopropylamino)silane (SiH3[N(C3H7)2], abbreviated as DIPAS) gases can be used instead of gases containing Si and halogens. One or more of these can be used as raw materials.

[0169] As a catalyst, for example, the same catalysts as those exemplified in step C above can be used.

[0170] [Step B2]

[0171] After step B1 is completed, an oxidant (oxidizing gas) and a catalyst (catalyst gas) are supplied to the wafer 200, which has selectively formed the first layer on the surface of the second material (SiGe) in the processing chamber 201, as film-forming substances.

[0172] Specifically, valves 243c and 243d are opened, allowing oxidant to flow into gas supply pipe 232c and catalyst to flow into gas supply pipe 232d, respectively. The oxidant and catalyst are supplied to the processing chamber 201 via nozzles 249c and 249a through flow regulation by MFCs 241c and 241d, respectively, where they are mixed and exhausted through exhaust port 231a. At this time, oxidant and catalyst (oxidant + catalyst supply) are supplied to the wafer 200. Then, valves 243f to 243h can be opened, supplying inactive gases to the processing chamber 201 via nozzles 249a to 249c.

[0173] By supplying an oxidant and a catalyst to the wafer 200 under the processing conditions described later, at least a portion of the first layer formed on the surface of the second material (SiGe) can be oxidized in step B1. Thus, a second layer formed by oxidizing the first layer is formed on the surface of the second material (SiGe).

[0174] In this step, by supplying the catalyst together with the oxidant, the above reaction can be carried out in a non-plasma atmosphere and at a low temperature as described later. Thus, by forming the second layer in a non-plasma atmosphere and at a low temperature as described later, the molecules and atoms constituting the film-forming inhibition layer formed on the surface of the first material (Si) are maintained and do not disappear (detach) from the surface of the first material (Si).

[0175] After the first layer formed on the surface of the second material (SiGe) is oxidized and transformed into the second layer, valves 243c and 243d are closed to stop the supply of oxidant and catalyst to the processing chamber 201, respectively. Then, using the same processing steps and conditions as in step E, residual gases in the processing chamber 201 are removed (purged). It should be noted that the processing temperature during purging in this step is preferably the same as the processing temperature during the supply of oxidant and catalyst.

[0176] Examples of processing conditions in the supply of oxidant and catalyst can be shown.

[0177] Processing temperature: room temperature (25℃) to 120℃, preferably room temperature to 100℃

[0178] Processing pressure: 133~1333Pa

[0179] Oxidant supply flow rate: 1–2000 sccm

[0180] Catalyst supply flow rate: 1–2000 sccm

[0181] Inactive gas supply flow rate (per gas supply tube): 0–20000 sccm

[0182] Gas supply time: 1 to 60 seconds.

[0183] As an oxidant, for example, the same oxidant as those exemplified in step C above can be used. As a catalyst, for example, the same catalyst as those exemplified in step C above can be used.

[0184] [Number of times stipulated for implementation]

[0185] By performing steps B1 and B2 asynchronously a predetermined number of times (n times, where n is an integer greater than or equal to 1), thus achieving... Figure 5 As shown in (b), the film can be selectively (preferably) grown on the surface of the second material (SiGe) of the first material (Si) and the second material (SiGe) in the recess on the surface of the wafer 200. For example, when using the above-described raw materials, oxidant, and catalyst, a SiOC film or a SiO film can be selectively grown on the surface of the second material (SiGe). The above-described cycle is preferably repeated multiple times. That is, it is preferable that the thickness of the second layer formed in each cycle is thinner than the desired film thickness, and the above-described cycle is repeated multiple times until the film thickness formed by stacking the second layer becomes the desired film thickness.

[0186] By repeating the above cycle multiple times, film growth can be achieved starting from the surface of the second material (SiGe) constituting the bottom surface of the recess on the surface of wafer 200, moving towards the opening side of the recess. At this time, since a film-forming inhibition layer is formed on the surface of the first material (Si) constituting the upper and side surfaces of the recess, film growth starting from the surface of the first material (Si) can be suppressed. That is, by repeating the above cycle multiple times, film growth starting from the upper and side surfaces of the recess can be suppressed, while film growth starting from the bottom surface of the recess can be promoted, allowing the film to grow from bottom to top within the recess. Figure 5 As shown in (c), the recess can be filled using a membrane (SiOC).

[0187] It should be noted that when implementing steps B1 and B2, if... Figure 5 (b) and Figure 5 As shown in (c), the film-forming inhibition layer formed on the surface of the first material (Si) is maintained on the surface of the first material (Si) as described above, thus suppressing the growth of the film originating from the surface of the first material (Si). However, in cases where the formation of the film-forming inhibition layer on the surface of the first material (Si) becomes insufficient for some reason, film growth originating from the surface of the first material (Si) may occur very rarely. However, even in this case, the thickness of the film formed originating from the surface of the first material (Si) is much thinner than the thickness of the film formed originating from the surface of the second material (SiGe). Therefore, in this case, the filling within the recess can be appropriately achieved through the aforementioned bottom-up growth.

[0188] (Step F: PT)

[0189] After the film formation process is completed, the wafer 200 is heated and subjected to heat treatment, thereby performing post-treatment (PT) on the film formed by filling the recesses. At this time, the output power of the heater 207 is adjusted so that the temperature inside the processing chamber 201, i.e., the temperature of the wafer 200 after the film is formed by filling the recesses, is higher than, and preferably higher than, the temperature of the wafer 200 in steps A and B. By performing PT, impurities contained in the film formed by filling the recesses can be removed and defects repaired. Furthermore, by performing PT, such as Figure 5As shown in (d), residues and slags of the film-forming inhibition layer in the surface of the first material (Si) (i.e., the interface between the upper surface of the recess or the side surface of the recess and the film (SiOC)) can be removed. It should be noted that this step can be performed with an inactive gas supplied to the processing chamber 201, or with a reactive substance such as an oxidant (oxidizing gas) supplied. When a reactive substance such as an oxidant is supplied, the effect of removing residues and slags of the film-forming inhibition layer in the interface between the upper surface of the recess or the side surface of the recess and the film is improved. The inactive gas and the reactive substance such as the oxidant (oxidizing gas) in this case are also referred to as auxiliary substances.

[0190] Examples of processing conditions in post-processing (PT) can be shown.

[0191] Processing temperature: 120–1000℃, preferably 400–700℃

[0192] Processing pressure: 1~120000Pa

[0193] Processing time: 1–18000 seconds

[0194] Auxiliary material supply flow rate: 0-50 slm.

[0195] (Post-purging and atmospheric pressure recovery)

[0196] After the film formation process and PT (Precipitation Tolerance) are completed, inert gases are supplied as purge gases into the treatment chamber 201 through nozzles 249a to 249c, and exhaust gases are discharged from the exhaust port 231a. This purges the treatment chamber 201, removing residual gases and reaction byproducts (post-purge). Subsequently, the atmosphere in the treatment chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure inside the treatment chamber 201 is restored to atmospheric pressure (atmospheric pressure restoration).

[0197] (Crystal boat unloading and chip removal)

[0198] Subsequently, the sealing cover 219 is lowered by the crystal boat lift 115, opening the lower end of the manifold 209. The processed wafer 200, supported by the crystal boat 217, is then removed from the lower end of the manifold 209 to the outside of the reaction tube 203 (crystal boat unloading). After unloading, the gate 219s moves, sealing the lower opening of the manifold 209 by means of an O-ring 220c (gate closing). The processed wafer 200, after being removed from the reaction tube 203, is then taken out of the crystal boat 217 (wafer removal).

[0199] (3) Effects of this method

[0200] According to this method, one or more of the following effects can be obtained.

[0201] (a) By performing the following steps, film growth originating from the upper and side surfaces of the recess can be suppressed, while film growth originating from the bottom surface of the recess can be promoted. These steps are: step A, supplying a precursor material to the wafer 200 to form a film-forming inhibition layer on the surface of a first material (Si) in the recess of the wafer 200; and step B, supplying a film-forming material to the wafer 200 on which the film-forming inhibition layer is formed, allowing the film to grow on the surface of a second material (SiGe) in the recess. This enables the film to grow from bottom to top within the recess, allowing the film to fill the recess without creating voids or seams. In other words, a void-free and seam-free film can be formed within the recess, improving filling characteristics.

[0202] (b) By suppressing membrane growth originating from the upper and side surfaces of the recess while promoting membrane growth originating from the bottom surface of the recess, it is possible to fill the recess with a membrane without allowing the membrane to grow on the upper surface of the recess. Thus, as... Figure 5 As shown in (c), it is possible to achieve a state where no film (SiOC) is formed on the upper surface of the recess at the end of the film deposition process. That is, at the end of the film deposition process, the film (SiOC) can be used to fill the recesses in the sidewalls of the stacked structure formed by alternating layers of the second material (SiGe) and the first material (Si) on the surface of the wafer 200, making the sidewalls flat. As a result, the previously required process of removing excess film formed on the upper surface of the recess by etching after the film deposition process can be omitted.

[0203] It should be noted that, as mentioned above, although a film-forming inhibition layer is formed on the surface of the first material, there are still cases where film growth originating from the surface of the first material is extremely rare for some reason. In such cases, it is sometimes necessary to etch away the excess film formed on the upper surface of the recess, etc. However, even in this case, as mentioned above, the excess film formed on the upper surface of the recess, etc., is extremely rare, which can significantly reduce the workload of the process of etching the excess film and significantly shorten the etching time.

[0204] On the other hand, when using conventional film-forming methods such as step B to fill the recess with a SiOC film or similar film, such as... Figure 6 As shown in (b), a film (SiOC) is formed on the entire sidewall of a stacked structure consisting of alternating layers of a second material (SiGe) and a first material (Si) on the surface of wafer 200. At this time, as... Figure 6As shown in (b), there are cases where voids or seams (hereinafter referred to as voids) are formed in the formed film due to the shape of the recess. In this case, in order to fill the recesses in the sidewalls of the laminated structure formed by alternately stacking the second and first materials using the film and to flatten the sidewalls, it is necessary to perform a process of etching the excess film formed on the upper surface of the recess, etc. For example, for surfaces having Figure 6 When performing the etching process on the substrate constituting (b) to remove excess film formed on the upper surface of the recess, such as... Figure 6 As shown in (c), a state in which no film forms on the upper surface of the recess can be produced. However, in this case, as... Figure 6 As shown in (c), the voids formed in the film during film formation are maintained. Depending on the situation, the voids become deeper due to etching, and there are cases where the sidewalls of the laminated structure formed by alternating layers of the second and first materials cannot be flattened. In addition, when using conventional film formation methods, a process of etching away excess film must be performed, which increases the total processing time and reduces productivity.

[0205] In contrast, according to this method, while suppressing film growth onto the upper surface of the recess, a void-free and seamless film can be formed within the recess. Furthermore, at the end of the film deposition process, the recesses in the sidewalls of the stacked structure formed by alternating layers of the second material (SiGe) and the first material (Si) can be filled with the film (SiOC), making the sidewalls flat. Therefore, the step of removing excess film from the upper surface of the recess after film deposition, which is necessary in conventional film deposition methods, can be omitted.

[0206] Regardless of whether a film-forming inhibition layer is formed on the surface of the first material, there are cases where film growth originating from the surface of the first material is extremely rare for some reason. In such cases, it is sometimes necessary to etch away the excess film formed on the upper surface of the recess, etc. However, even in this case, as mentioned above, the excess film formed on the upper surface of the recess, etc., is extremely rare, which can significantly reduce the workload of the process of etching the excess film and significantly shorten the etching time.

[0207] Even when a film-forming inhibition layer is formed on the surface of the first material, but film growth originating from the surface of the first material is minimal for some reason, the excess film formed on the upper surface of the recess, etc., is also minimal. This significantly reduces the workload of the process of etching the excess film and greatly shortens the etching time. In other words, according to this method, not only can gapless and seamless filling be achieved and filling characteristics improved, but also the total processing time can be shortened and productivity improved by omitting the process of etching the excess film or reducing the workload of the process of etching the excess film.

[0208] (c) By forming OH-terminated surfaces on the surface of the first material, which forms a recess in the wafer 200 surface before step A, at least a portion of the molecular structure constituting the precursor substance is adsorbed onto the surface of the first material in the recess, and a film-forming inhibition layer can be appropriately formed on the surface of the first material. Furthermore, in this case, by ensuring that the amount (density, concentration) of OH-terminated surfaces on the first material (Si) before step A is greater than the amount (density, concentration) of OH-terminated surfaces on the second material (SiGe), at least a portion of the molecular structure constituting the precursor substance is selectively (preferably) adsorbed onto the surface of the first material in both the recessed first material and the second material, and a film-forming inhibition layer can be selectively (preferably) formed on the surface of the first material. It should be noted that it is also possible for the surface of the second material before step A not to have OH-terminated surfaces. In this case, the selective adsorption of at least a portion of the molecular structure constituting the precursor substance onto the surface of the first material can be improved, and the selective formation of the film-forming inhibition layer on the surface of the first material can be improved.

[0209] (d) By performing step C, which forms OH caps on the surface of the first material in the recess of the wafer 200 before step A, it is possible to promote the adsorption of at least a portion of the molecular structure constituting the precursor molecules onto the surface of the first material in the recess, and to appropriately form a film-forming inhibition layer on the surface of the first material. By supplying the wafer 200 with, for example, an oxidant as a reactant in step C to oxidize the surface of the first material, the formation of OH caps on the surface of the first material can be effectively and controllably achieved. In this case, OH caps are also formed on the surface of the second material in step C, but by performing step D, which removes the OH caps formed on the surface of the second material after step C and before step A, it is possible to produce a state in which no OH caps are formed on the surface of the second material. It should be noted that by annealing the wafer 200 by heating in step D, it is possible to selectively sublimate and remove oxides such as GeO formed on the surface of the second material (SiGe) while maintaining the oxide film such as SiO formed on the surface of the first material (Si). That is, by heating only the wafer 200 in step D, it is possible to selectively remove the OH end caps formed on the surface of the second material (SiGe) while keeping the OH end caps formed on the surface of the first material (Si).

[0210] Therefore, the amount (density, concentration) of OH-terminated molecules on the surface of the first material (Si) before step A is greater than that on the surface of the second material (SiGe), enabling at least a portion of the molecular structure constituting the precursor to selectively (preferably) adsorb onto the surface of the first material in both the recessed first and second materials, thus selectively (preferably) forming a film-forming inhibition layer on the surface of the first material. It should be noted that by sufficiently performing annealing in step D, it is also possible to achieve a state where OH-terminated molecules do not form on the surface of the second material before step A. In this case, the selective adsorption of at least a portion of the molecular structure constituting the precursor to the surface of the first material and the selectivity of the film-forming inhibition layer formation on the surface of the first material can be improved.

[0211] (e) By performing step E, which removes the natural oxide film from the surfaces of the first and second materials in the recesses of the wafer 200 before step C, it is possible to remove oxide films that may form unevenly on the surfaces of the first and second materials, thereby removing OH caps that may form unevenly on the surfaces of the first and second materials. Then, by performing step C, the surface of the first material can be uniformly oxidized, and an oxide film can be uniformly formed on the surface of the first material. As a result, OH caps can be uniformly formed on the surface of the first material. Thus, in step A, at least a portion of the molecular structure constituting the precursor substance can be more uniformly adsorbed onto the surface of the first material in the recesses, and a film-forming inhibition layer can be formed more uniformly on the surface of the first material.

[0212] (f) After step B, by raising the temperature of wafer 200 to above (preferably higher than) the temperature of wafer 200 in steps A and B, the film formed by filling the recesses is subjected to post-treatment (PT), thereby removing impurities and repairing defects contained in the film formed by filling the recesses. Furthermore, residues and slags of the film-forming inhibition layer on the surface of the first material (i.e., the upper surface of the recess or the interface between the side of the recess and the film) can be removed. This can be performed by supplying an inactive gas into the processing chamber 201 or by supplying a reactive substance such as an oxidant (oxidizing gas). When a reactive substance such as an oxidant is supplied, the effect of removing residues and slags of the film-forming inhibition layer on the upper surface of the recess or the interface between the side of the recess and the film is improved.

[0213] (g) Each reaction in each step can be carried out in a non-plasma atmosphere, which can suppress excessive reaction in each step and improve the controllability of the reaction. In addition, since each step is carried out in a non-plasma atmosphere, damage to the wafer 200 by plasma can be avoided, and this method can also be applied to processes where plasma damage is a concern.

[0214] (4) Variations

[0215] The substrate processing sequence in this method can be modified as described in the following variations. These variations can be combined arbitrarily. Unless otherwise specified, the processing steps and conditions in each step of each variation can be set to be the same as the processing steps and conditions in each step of the above-described substrate processing sequence.

[0216] (Variation Example 1)

[0217] As shown in the following processing sequence, step E (removing the native oxide film) can be omitted depending on the surface condition of wafer 200. For example, a oxide film is formed on the surface of wafer 200. Figure 5 In step (a), after the second material (SiGe) and the first material (Si) are alternately stacked, the surfaces of the first material and the second material are in appropriate surface conditions in cases where the surface of the wafer 200 is not exposed to the atmosphere, or the amount of atmospheric exposure is low, or the atmospheric exposure time is short. In such cases, step E can be omitted, and the processing sequence can start from step C (oxidation). In this modified example, the same effect as described above can be obtained. In addition, by omitting step E, the total processing time can be shortened, and productivity can be improved.

[0218] Oxidizing agent → ANL → Precursor → (Reagent + Catalyst → Oxidizing agent + Catalyst) × n → PT

[0219] (Variation Example 2)

[0220] As shown in the processing sequence below, steps E (natural oxide film removal) and C (oxidation) can be omitted depending on the surface condition of the wafer 200. For example, if an oxide film is uniformly formed on the surfaces of the first material (Si) and the second material (SiGe) on the surface of the wafer 200, steps E and C can be omitted, and the processing sequence can begin from step D (ANL). In this modified example, the same effect as described above can be obtained. Furthermore, by omitting steps E and C, the total processing time can be shortened, and productivity can be improved.

[0221] ANL → Precursor → (Raw Material + Catalyst → Oxidant + Catalyst) × n → PT

[0222] (Variation Example 3)

[0223] As shown in the processing sequence below, steps E (removal of natural oxide film), C (oxidation), and D (ANL) can be omitted depending on the surface state of the wafer 200. For example, if an oxide film is uniformly formed on the surfaces of the first and second materials on the surface of the wafer 200, and the wafer 200 is heated to a temperature of, for example, 100°C or higher in step A (formation of film inhibition layer), in step A, oxides such as GeO formed on the surface of the second material can be removed by sublimation while the oxide film such as SiO formed on the surface of the first material remains (maintained). That is, in step A, OH end caps formed on the surface of the second material can be removed while the OH end caps formed on the surface of the first material remains (maintained). In this case, steps E, C, and D can be omitted, and the processing sequence can start from step A. In this modified example, the same effect as described above can also be obtained. In addition, by omitting steps E, C, and D, the total processing time can be shortened, and productivity can be improved.

[0224] Precursor → (raw material + catalyst → oxidant + catalyst) × n → PT

[0225] (Variation Example 4)

[0226] As shown in the following processing sequence, in step B1, the raw material can be supplied alone without supplying a catalyst to the wafer 200. Similarly, in step B2, the oxidant can be supplied alone without supplying a catalyst to the wafer 200. By supplying both the raw material and the catalyst to the wafer 200, at least a portion of the molecular structure constituting the raw material can be chemically adsorbed onto the surface of the second material at low temperatures. Furthermore, by supplying both the oxidant and the catalyst to the wafer 200, the oxidation rate can be increased at low temperatures. However, in cases where temperature is used to regulate the chemical adsorption of at least a portion of the molecular structure constituting the raw material onto the surface of the second material, or the oxidation rate, the supply of the catalyst can be omitted. In this modified example, the same effects as described above can also be obtained.

[0227] Etching agent → Oxidizing agent → ANL → Precursor → (Raw material → Oxidizing agent + Catalyst) × n → PT

[0228] Etching agent → Oxidizing agent → ANL → Precursor → (Raw material + Catalyst → Oxidizing agent) × n → PT

[0229] Etching agent → Oxidizing agent → ANL → Precursor → (Raw material → Oxidizing agent) × n → PT

[0230] (Variation Example 5)

[0231] As shown in the following processing sequence, step F (PT) can also be omitted. For example, if the amount of impurities in the film formed by filling the recess is within acceptable limits, step F can be omitted. Furthermore, if the amount of film-forming inhibition layer residues or other contaminants remaining on the upper surface of the recess or at the interface between the recess's side and the film is acceptable, then step F can also be omitted if the amount of film-forming inhibition layer residues or other contaminants on the upper surface of the recess or at the interface between the recess's side and the film is within acceptable limits. Additionally, if the film-forming inhibition layer or other contaminants on the upper surface of the recess or at the interface between the recess's side and the film are removed by reactions in the various steps of the film-forming process, then step F can be omitted. In this modified example, the same effect as described above can be obtained. Furthermore, by omitting step F, the total processing time can be shortened, and productivity can be improved.

[0232] Etching agent → Oxidizing agent → ANL → Precursor → (Raw material + Catalyst → Oxidizing agent + Catalyst) × n

[0233] <Other ways of publishing this text>

[0234] The foregoing has specifically described the manner of this disclosure. However, this disclosure is not limited to the manner described above and various changes may be made without departing from its spirit.

[0235] For example, in step E, the etchant can be plasma-excited and supplied to the wafer 200. This increases the etching rate when etching the native oxide film. Additionally, in step C, the oxidant or other reactive substances can be plasma-excited and supplied to the wafer 200. This increases the oxidation rate. Furthermore, in step D, an inactive gas can be plasma-excited and supplied. This allows for the removal of oxides such as GeO formed on the surface of the second material by sublimation, while simultaneously treating the surface of the second material after oxide removal. Additionally, in step D, an auxiliary substance can be plasma-excited and supplied. This further improves the effect of removing residues and slag from the film-forming inhibition layer at the interface between the upper surface or side surface of the recess and the film.

[0236] Alternatively, in step B, not only SiOC films and SiO films can be formed, but also silicon-based oxide films such as silicon-oxygen-carbon nitride films (SiOCN films), silicon-oxygen-nitride films (SiON films), silicon-boron-oxygen-nitride films (SiBON films), and silicon-boron-oxygen-carbon nitride films (SiBOCN films) can be formed. Additionally, in step B, for example, metal-based oxide films such as aluminum oxide films (AlO films), titanium oxide films (TiO films), hafnium oxide films (HfO films), and zirconium oxide films (ZrO films) can be formed.

[0237] The processes used in each process are preferably prepared individually according to the process content and stored in advance in the storage device 121c via an electrical communication line and an external storage device 123. Furthermore, preferably at the start of each process, the CPU 121a selects an appropriate process from among the multiple processes stored in the storage device 121c according to the process content. This allows for the reproducible formation of films of various types, compositions, qualities, and thicknesses within a single substrate processing apparatus. It also reduces the operator's workload, avoids operational errors, and enables rapid commencement of each process.

[0238] The aforementioned process is not limited to newly created cases; for example, it can also be prepared by modifying an existing process already installed in the substrate processing apparatus. In the case of process modification, the modified process can also be installed in the substrate processing apparatus via an electrical communication line and a recording medium containing the corresponding process. Alternatively, the input / output device 122 of an existing substrate processing apparatus can be operated to directly modify the existing process already installed in the substrate processing apparatus.

[0239] In the above-described method, an example of forming a film using a batch substrate processing apparatus that processes multiple substrates at a time has been described. The present invention is not limited to the above-described method; for example, it can also be appropriately applied when forming a film using a monolithic substrate processing apparatus that processes one or several substrates at a time. Furthermore, in the above-described embodiment, an example of forming a film using a substrate processing apparatus equipped with a hot-wall type processing furnace has been described. The present invention is not limited to the above-described method; it can also be appropriately applied when forming a film using a substrate processing apparatus equipped with a cold-wall type processing furnace.

[0240] When using these substrate processing devices, each process can be performed using the same processing steps and conditions as described above to achieve the same effect as described above.

[0241] The above methods can be used in appropriate combinations. In this case, the processing steps and conditions can be the same as those in the methods described above.

[0242] Example

[0243] Using the substrate processing apparatus described above, for Figure 5 As shown in (a), a wafer with an alternating SiGe and Si film stacked on its surface and having a recess as described above was processed in the aforementioned sequence. The upper and side surfaces of the recess are composed of Si films, the bottom surface is composed of SiGe films, and the depth direction is parallel to the surface of the wafer (lateral direction). Thus, a SiOC film is formed by filling the recess, thereby creating evaluation sample 1. Then, a cross-sectional TEM image of evaluation sample 1 was taken. Figure 7 The image shown is a cross-sectional TEM image of evaluation sample 1.

[0244] Using the substrate processing apparatus described above, the processing sequence of Modified Example 3 was performed on a wafer with the same structure as the wafer used to fabricate Evaluation Sample 1, thereby forming a SiOC film by filling the recesses, and Evaluation Sample 2 was fabricated. Then, a cross-sectional TEM image of Evaluation Sample 2 was taken. Figure 8 The image shown is a cross-sectional TEM image of evaluation sample 2.

[0245] like Figure 7 As shown, in evaluation sample 1, the SiOC film does not form on the upper surface of the recess, but only selectively forms within the recess. Furthermore, it is evident that no voids or seams are generated in the SiOC film formed within the recess. It should be noted that, during the preparation of evaluation sample 1, by controlling (increasing) the number of cycles in step B, it is possible to suppress the growth of the SiOC film onto the upper surface of the recess while simultaneously allowing the SiOC film to selectively grow within the recess. This enables the SiOC film to fill the recesses in the sidewalls of the stacked structure formed by alternating SiGe and Si films, making the sidewalls flat.

[0246] like Figure 8 As shown, in evaluation sample 2, a SiOC film without voids or seams is formed by filling the recess. It should be noted that, although a slight SiOC film is also formed on the upper surface of the recess in evaluation sample 2, the SiOC film has a flat profile in the sidewalls of the stacked structure formed by alternating layers of SiGe and Si films. It should be noted that, in this case, by etching away the SiOC film formed on the sidewalls of the stacked structure formed by alternating layers of SiGe and Si films with the same thickness as the SiOC film formed on the upper surface of the recess, the sidewalls of the stacked structure can be kept flat, while exposing the Si film in the sidewalls, i.e., the upper surface (Si) of the recess. It should be noted that, when preparing evaluation sample 2, by controlling (reducing) the number of cycles in step B, the film formation is stopped when the SiOC film is used to fill the recess. This allows the sidewalls of the stacked structure formed by alternating SiGe and Si films to become flat without forming a SiOC film on the upper surface of the recess.

Claims

1. A substrate processing method, comprising the following steps: (a) A step of supplying a precursor material to a substrate having recesses on its surface, such that at least a portion of the molecular structure constituting the precursor material is adsorbed onto the surface of a first material in the recesses, thereby forming a film-forming inhibition layer on the surface of the first material, wherein, The upper surface and side surface of the recess are made of the first material containing the first element, and the bottom surface of the recess is made of the second material containing the second element, which is different from the first element. (b) A process of growing a film on the surface of the second material in the recess by supplying a film-forming substance to the substrate on which the film-forming inhibition layer is formed; (c) A process prior to (a) of preparing a substrate in a state where the surfaces of the first material and the second material are oxidized and hydroxyl-terminated on their respective surfaces; and, (d) A process of removing the hydroxyl end caps formed on the surface of the second material by heating the substrate after (c) and before (a) to leave the hydroxyl end caps formed on the surface of the first material residual, while sublimating the oxide formed on the surface of the second material to remove them.

2. The substrate processing method as described in claim 1, wherein, The amount of hydroxyl end-capping on the surface of the first material prior to (a) is greater than the amount of hydroxyl end-capping on the surface of the second material prior to (a).

3. The substrate processing method as described in claim 1, wherein, Before (a), the surface of the second material was not capped with hydroxyl groups.

4. The substrate processing method as described in claim 1, further comprising: In (c), a process of forming hydroxyl end caps on the surfaces of the first material and the second material in a non-plasma atmosphere.

5. The substrate processing method as described in claim 1, wherein, In (c), a reactive substance is supplied to the substrate to oxidize the surfaces of the first material and the second material, thereby forming hydroxyl end caps on the surfaces of the first material and the second material.

6. The substrate processing method as described in claim 1, further comprising: (e) A process of removing the natural oxide film on the surfaces of the first material and the second material prior to (c).

7. The substrate processing method as described in claim 1, wherein, In (b), the membrane is grown from bottom to top within the recess by growing the membrane on the surface of the second material in the recess, and the recess is filled using the membrane.

8. The substrate processing method as described in claim 1, wherein, In (b), the following processes will be performed a specified number of times: (b1) The step of supplying raw materials to the substrate as the film-forming substance; and, (b2) The process of supplying the reactant to the substrate as the film-forming substance.

9. The substrate processing method as described in claim 8, wherein, In at least one of (b1) and (b2), a catalyst is further supplied to the substrate as the film-forming material.

10. The substrate processing method as described in claim 1, wherein, The second material also contains the first element.

11. The substrate processing method according to any one of claims 1 to 10, wherein, The first element is silicon, and the second element is germanium.

12. The substrate processing method according to any one of claims 1 to 10, wherein, The first material is silicon, and the second material is silicon-germanium.

13. The substrate processing method according to any one of claims 1 to 10, wherein, In (b), a membrane containing silicon, oxygen, and carbon is grown as the membrane.

14. A method for manufacturing a semiconductor device, comprising the following steps: (a) A step of supplying a precursor material to a substrate having recesses on its surface, such that at least a portion of the molecular structure constituting the precursor material is adsorbed onto the surface of a first material in the recesses, thereby forming a film-forming inhibition layer on the surface of the first material, wherein, The upper surface and side surface of the recess are made of the first material containing the first element, and the bottom surface of the recess is made of the second material containing the second element, which is different from the first element. (b) A process of growing a film on the surface of the second material in the recess by supplying a film-forming substance to the substrate on which the film-forming inhibition layer is formed; (c) A process prior to (a) of preparing a substrate in a state where the surfaces of the first material and the second material are oxidized and hydroxyl-terminated on their respective surfaces; and, (d) A process of removing the hydroxyl end caps formed on the surface of the second material by heating the substrate after (c) and before (a) to leave the hydroxyl end caps formed on the surface of the first material residual, while sublimating the oxide formed on the surface of the second material to remove them.

15. A substrate processing apparatus, comprising: A precursor material supply system that supplies precursor materials to a substrate; A film-forming material supply system that supplies film-forming materials to a substrate; Heater, which heats the substrate; and, The control unit is configured to control the precursor material supply system, the film-forming material supply system, and the heater in a manner that allows for the following processing: (a) A process of supplying the precursor material to a substrate having the following recesses on its surface, causing at least a portion of the molecular structure constituting the precursor material to adsorb onto the surface of a first material in the recesses, thereby forming a film-forming inhibition layer on the surface of the first material, wherein, The upper surface and side surface of the recess are made of the first material containing the first element, and the bottom surface of the recess is made of the second material containing the second element, which is different from the first element. and, (b) A process in which a film is grown on the surface of the second material in the recess by supplying the film-forming substance to the substrate on which the film-forming inhibition layer is formed on the surface of the first material; (c) Prior to (a), a substrate is prepared by processing such a substrate having hydroxyl-terminated ends on its respective surfaces due to oxidation of the surfaces of the first material and the second material; and, (d) After (c) and before (a), the substrate is heated to leave hydroxyl end caps formed on the surface of the first material, while the oxide formed on the surface of the second material is sublimated to remove them, thereby removing the hydroxyl end caps formed on the surface of the second material.

16. A computer-readable recording medium containing a program that enables a substrate processing apparatus to perform the following steps using a computer: (a) A step of supplying a precursor material to a substrate having recesses on its surface, such that at least a portion of the molecular structure constituting the precursor material is adsorbed onto the surface of a first material in the recesses, thereby forming a film-forming inhibition layer on the surface of the first material, wherein, The upper surface and side surface of the recess are made of the first material containing the first element, and the bottom surface of the recess is made of the second material containing the second element, which is different from the first element. (b) The step of growing a film on the surface of the second material in the recess by supplying a film-forming substance to the substrate on which the film-forming inhibition layer is formed; (c) The step of preparing a substrate prior to (a), wherein the substrate is in a state in which hydroxyl groups are formed on the respective surfaces of the first material and the second material, respectively, by oxidation; and, (d) After (c) and before (a), the substrate is heated to leave hydroxyl end caps formed on the surface of the first material, while the oxide formed on the surface of the second material is sublimated to remove them, thereby removing the hydroxyl end caps formed on the surface of the second material.

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