Processing method, method for manufacturing a semiconductor device, processing apparatus, and program

Abstract

This invention provides a technology that enables efficient etching of oxide films on the surface of a substrate. [Solution] (a) A step of preparing a substrate having a nitrogen-containing film formed on its surface with a thickness T2 greater than the originally required thickness T1, and an oxide film; (b) A step of etching the oxide film on the surface of the substrate using a substance X generated by chemically reacting the nitrogen-containing film and the fluorine-containing substance by supplying a fluorine-containing substance to the substrate.

Description

Technical Field

[0001] The present disclosure relates to a processing method, a method for manufacturing a semiconductor device, a processing apparatus, and a program.

Background Art

[0002] As one step in the manufacturing process of a semiconductor device, a process of etching an oxide film on the surface of a substrate may be performed (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technology capable of efficiently etching an oxide film on the surface of a substrate.

Means for Solving the Problems

[0005] According to one aspect of the present disclosure, (a) preparing a substrate having a nitrogen - containing film formed thicker by a thickness T2 than an originally required thickness T1 and an oxide film on its surface; (b) supplying a fluorine - containing substance to the substrate, and etching the oxide film on the surface of the substrate using a substance X generated by chemically reacting the nitrogen - containing film and the fluorine - containing substance. A technology having the above is provided.

Effects of the Invention

[0006] According to the present disclosure, it becomes possible to efficiently etch an oxide film on the surface of a substrate.

Brief Description of the Drawings

[0007] [Figure 1] Figure 1 is a schematic diagram of a vertical processing furnace of a processing apparatus preferably used in one embodiment of the present disclosure, and shows the processing furnace 202 portion in a vertical cross-sectional view. [Figure 2] Figure 2 is a schematic diagram of a vertical processing furnace of a processing apparatus preferably used in one embodiment of the present disclosure, and shows the processing furnace 202 portion as a cross-sectional view along line AA in Figure 1. [Figure 3] Figure 3 is a schematic configuration diagram of a controller 121 of a processing device preferably used in one embodiment of the present disclosure, and is a block diagram showing the control system of the controller 121. [Figure 4] Figure 4(a) is a partially enlarged cross-sectional view showing the surface portion of a substrate in one embodiment of this disclosure, having a laminated film of a first nitrogen (N)-containing film and a second nitrogen (N)-containing film on its surface, and an oxide film formed on the substrate. Figure 4(b) is a partially enlarged cross-sectional view showing the surface portion of a substrate in one embodiment of this disclosure after supplying a fluorine (F)-containing substance from the state in Figure 4(a) to chemically react the surface of the second N-containing film with the F-containing substance to produce a reaction product. Figure 4(c) is a partially enlarged cross-sectional view showing the surface portion of a substrate in one embodiment of this disclosure after continuing to supply the F-containing substance from the state in Figure 4(b) to decompose the reaction product and produce substance X. Figure 4(d) is a partially enlarged cross-sectional view showing the surface portion of a substrate in one embodiment of this disclosure after continuing to supply the F-containing substance from the state in Figure 4(c) to etch a portion of the surface side of the oxide film using substance X. Figure 4(e) is a partially enlarged cross-sectional view showing the surface portion of the substrate in one embodiment of this disclosure after the F-containing substance has been continuously supplied from the state shown in Figure 4(d), the second N-containing film and the oxide film have been removed, and the surfaces of the first N-containing film and the substrate have been exposed. Figure 4(f) is a partially enlarged cross-sectional view showing the surface portion of the substrate in one embodiment of this disclosure after films have been formed on the surfaces of the first N-containing film and the substrate from the state shown in Figure 4(e). [Figure 5]Figure 5(a) is a partially enlarged cross-sectional view showing the surface portion of a substrate in a modified example of one aspect of the present disclosure, having a first N-containing film on its surface and an oxide film formed on the substrate. Figure 5(b) is a partially enlarged cross-sectional view showing the surface portion of a substrate in a modified example of one aspect of the present disclosure after an inhibitor has been adsorbed onto the surface of the oxide film, from the state shown in Figure 5(a). Figure 5(c) is a partially enlarged cross-sectional view showing the surface portion of a substrate in a modified example of one aspect of the present disclosure after a second N-containing film has been formed on the first N-containing film, from the state shown in Figure 5(b). Figure 5(d) is a partially enlarged cross-sectional view showing the surface portion of a substrate in a modified example of one aspect of the present disclosure after the inhibitor remaining on the surface of the oxide film has been removed, from the state shown in Figure 5(c). [Figure 6] Figure 6(a) is a partially enlarged cross-sectional view showing the surface portion of a substrate in a modified example of one aspect of the present disclosure, having an oxide film formed on the substrate surface. Figure 6(b) is a partially enlarged cross-sectional view showing the surface portion of a substrate in a modified example of one aspect of the present disclosure after an inhibitor has been adsorbed onto the surface of the oxide film, from the state shown in Figure 6(a). Figure 6(c) is a partially enlarged cross-sectional view showing the surface portion of a substrate in a modified example of one aspect of the present disclosure after a laminated film of a first N-containing film and a second N-containing film has been formed on the surface, from the state shown in Figure 6(b). Figure 6(d) is a partially enlarged cross-sectional view showing the surface portion of a substrate in a modified example of one aspect of the present disclosure after the inhibitor remaining on the surface of the oxide film has been removed, from the state shown in Figure 6(c). [Figure 7]Figure 7(a) is a partially enlarged cross-sectional view showing a surface portion of a substrate in another embodiment of the present disclosure, having a first substrate and a second substrate on its surface, with an oxide film formed on the surface of the first substrate and an N-containing film formed on the surface of the second substrate. Figure 7(b) is a partially enlarged cross-sectional view showing a surface portion of a substrate in another embodiment of the present disclosure after supplying an F-containing substance from the state of Figure 7(a) to chemically react the surface of the N-containing film with the F-containing substance to produce a reaction product. Figure 7(c) is a partially enlarged cross-sectional view showing a surface portion of a substrate in another embodiment of the present disclosure after continuing to supply the F-containing substance from the state of Figure 7(b) to decompose the reaction product and produce substance X. Figure 7(d) is a partially enlarged cross-sectional view showing a surface portion of a substrate in another embodiment of the present disclosure after continuing to supply the F-containing substance from the state of Figure 7(c) to etch a portion of the surface side of the oxide film using substance X. Figure 7(e) is a partially enlarged cross-sectional view showing the surface portion of the substrate in another embodiment of the disclosure after the F-containing substance has been continuously supplied, the N-containing film and oxide film have been removed, and the surfaces of the second and first substrates have been exposed, starting from the state shown in Figure 7(d). Figure 7(f) is a partially enlarged cross-sectional view showing the surface portion of the substrate in another embodiment of the disclosure after films have been formed on the surfaces of the second and first substrates, starting from the state shown in Figure 7(e). [Figure 8] Figure 8(a) is a partially enlarged cross-sectional view showing a surface portion of a substrate in another embodiment of the present disclosure, having a first substrate and a second substrate on its surface, with an oxide film formed on the surface of the first substrate. Figure 8(b) is a partially enlarged cross-sectional view showing a surface portion of a substrate in another embodiment of the present disclosure after an inhibitor has been adsorbed onto the surface of the oxide film, starting from the state shown in Figure 8(a). Figure 8(c) is a partially enlarged cross-sectional view showing a surface portion of a substrate in another embodiment of the present disclosure after an N-containing film has been formed on the surface of the second substrate, starting from the state shown in Figure 8(b). Figure 8(d) is a partially enlarged cross-sectional view showing a surface portion of a substrate in another embodiment of the present disclosure after the inhibitor remaining on the surface of the oxide film has been removed, starting from the state shown in Figure 8(c). [Figure 9] Figure 9 is a schematic diagram of a processing apparatus preferably used in other embodiments of the present disclosure. [Figure 10]Figure 10 is a schematic diagram of a processing apparatus preferably used in other embodiments of the present disclosure. [Modes for carrying out the invention]

[0008] <One aspect of this disclosure> The following description will explain one aspect of this disclosure, primarily with reference to Figures 1 to 3 and Figures 4(a) to 4(f). It should be noted that the drawings used in the following description are schematic, and the dimensional relationships and proportions of the elements shown in the drawings do not necessarily correspond to reality. Furthermore, the dimensional relationships and proportions of the elements do not necessarily correspond between multiple drawings.

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

[0010] Inside the heater 207, a reaction tube 203 is arranged concentrically with the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC), and is formed in a cylindrical shape with a closed upper end and an open lower end. Below the reaction tube 203, a manifold 209 is arranged concentrically with the reaction tube 203. The manifold 209 is made of a metal material such as stainless steel (SUS), and is formed in a cylindrical shape with open upper and lower ends. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 and is configured 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, similar to the heater 207. The reaction vessel (reaction vessel) is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed in the hollow cylindrical portion of the processing container. The processing chamber 201 is configured to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed within this processing chamber 201.

[0011] Within the processing chamber 201, nozzles 249a to 249c, which serve as the first to third supply units, are provided so as to penetrate the side walls 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 a heat-resistant material such as quartz or SiC. Gas supply pipes 232a to 232c are connected to nozzles 249a to 249c, respectively. Nozzles 249a to 249c are all different nozzles, and nozzles 249a and 249c are each provided adjacent to nozzle 249b.

[0012] Gas supply pipes 232a to 232c are equipped with mass flow controllers (MFCs) 241a to 241c and valves 243a to 243c, respectively, in order from the upstream side of the gas flow. Downstream of valve 243a in gas supply pipe 232a, gas supply pipes 232d and 232f are connected, respectively. Downstream of valve 243b in gas supply pipe 232b, gas supply pipes 232e and 232g are connected, respectively. Downstream of valve 243c in gas supply pipe 232c, gas supply pipe 232h is connected. Gas supply pipes 232d to 232h are equipped with MFCs 241d to 241h and valves 243d to 243h, respectively, in order from the upstream side of the gas flow. Gas supply pipes 232a to 232h are made of a metal material such as SUS.

[0013] As shown in FIG. 2, the nozzles 249a to 249c are provided so as to rise upward in the arrangement direction of the wafers 200 along the upper part from the lower part of the inner wall of the reaction tube 203 in an annular space in a plan view between the inner wall of the reaction tube 203 and the wafers 200. That is, the nozzles 249a to 249c are respectively provided along the wafer arrangement region in a region on the side of the wafer arrangement region where the wafers 200 are arranged and horizontally surrounding the wafer arrangement region. In a plan view, the nozzle 249b is arranged so as to face the exhaust port 231a described later in a straight line across the center of the wafer 200 in the processing chamber 201. The nozzles 249a and 249c are arranged so as to sandwich the straight line L passing through the centers of the nozzle 249b and the exhaust port 231a from both sides along the inner wall of the reaction tube 203 (the outer peripheral portion of the wafer 200). The straight line L is also a straight line passing through the nozzle 249b and the center of the wafer 200. That is, it can also be said that the nozzle 249c is provided on the opposite side of the nozzle 249a across the straight line L. The nozzles 249a and 249c are arranged symmetrically with the straight line L as the axis of symmetry. Gas supply holes 250a to 250c for supplying gas are respectively provided on the side surfaces of the nozzles 249a to 249c. The gas supply holes 250a to 250c are each opened so as to face (opposite) the exhaust port 231a in a plan view, and it is possible to supply gas toward the wafer 200. A plurality of gas supply holes 250a to 250c are provided from the lower part to the upper part of the reaction tube 203.

[0014] From the gas supply pipe 232a, a fluorine (F) - containing substance is supplied into the processing chamber 201 via the MFC241a, the valve 243a, and the nozzle 249a.

[0015] From the gas supply pipe 232b, the first raw material and the second raw material are supplied into the processing chamber 201 via the MFC241b, the valve 243b, and the nozzle 249b. The first raw material is used as one of the first film - forming agents. The second raw material is used as one of the second film - forming agents.

[0016] From the gas supply pipe 232c, the dopant agent is supplied into the processing chamber 201 via the MFC 241c, valve 243c, and nozzle 249c. The dopant agent is used as one of the first film-forming agents.

[0017] From the gas supply pipe 232d, the reforming agent is supplied into the processing chamber 201 via the MFC 241d, valve 243d, gas supply pipe 232a, and nozzle 249a.

[0018] From the gas supply pipe 232e, the reactant and removal agent are supplied into the processing chamber 201 via the MFC 241e, valve 243e, gas supply pipe 232b, and nozzle 249b. The reactant is used as one of the second film-forming agents.

[0019] Inert gas is supplied from gas supply pipes 232f to 232h into the processing chamber 201 via MFCs 241f to 241h, valves 243f to 243h, gas supply pipes 232a to 232c, and nozzles 249a to 249c, respectively. The inert gas acts as a purge gas, carrier gas, diluent gas, etc.

[0020] The F-containing substance supply system is mainly composed of gas supply pipe 232a, MFC 241a, and valve 243a. The first raw material supply system and the second raw material supply system are mainly composed of gas supply pipe 232b, MFC 241b, and valve 243b. The dopant agent supply system is mainly composed of gas supply pipe 232c, MFC 241c, and valve 243c. The reformer supply system is mainly composed of gas supply pipe 232d, MFC 241d, and valve 243d. The reactant supply system and the removal agent supply system are mainly composed of gas supply pipe 232e, MFC 241e, and valve 243e. The inert gas supply system is mainly composed of gas supply pipes 232f to 232h, MFC 241f to 241h, and valves 243f to 243h. The first raw material supply system, the dopant supply system, or all of them together may also be referred to as the first film-forming agent supply system. The second raw material supply system, the reactant supply system, or all of them together may also be referred to as the second film-forming agent supply system.

[0021] Of the various supply systems described above, one or all of them may be configured as an integrated supply system 248, which is comprised of valves 243a to 243h and MFCs 241a to 241h. The integrated supply system 248 is connected to each of the gas supply pipes 232a to 232h, and the supply operation of various substances (various gases) into the gas supply pipes 232a to 232h, i.e., the opening and closing operation of valves 243a to 243h and the flow rate adjustment operation of MFCs 241a to 241h, is controlled by a controller 121, which will be described later. The integrated supply system 248 is configured as an integrated or segmented integrated unit, and can be attached to and detached from the gas supply pipes 232a to 232h, etc., in units of the integrated unit, and is configured so that maintenance, replacement, and expansion of the integrated supply system 248 can be performed in units of the integrated unit.

[0022] An exhaust port 231a for exhausting the atmosphere inside the processing chamber 201 is provided at the lower part of the side wall of the reaction tube 203. As shown in Figure 2, the exhaust port 231a is located in a position opposite (facing) the nozzles 249a to 249c (gas supply holes 250a to 250c) with the wafer 200 in between, in a plan view. The exhaust port 231a may also be provided along the upper part of the side wall of the reaction tube 203, that is, along the wafer arrangement region. An exhaust pipe 231 is connected to the exhaust port 231a. A vacuum pump 246, which is a vacuum evacuation device, is connected to the exhaust pipe 231 via a pressure sensor 245, which is a pressure detector (pressure detection unit) for detecting the pressure inside the processing chamber 201, and an APC (Auto Pressure Controller) valve 244, which is a pressure regulator (pressure adjustment unit). The APC valve 244 can be opened and closed while the vacuum pump 246 is operating to evacuate and stop the vacuum evacuation in the processing chamber 201. Furthermore, while the vacuum pump 246 is operating, the valve opening can be adjusted based on the pressure information detected by the pressure sensor 245 to adjust the pressure in the processing chamber 201. The exhaust system mainly consists of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may also be included in the exhaust system.

[0023] Below the manifold 209, a seal cap 219 is provided as a furnace opening cover capable of airtightly closing the lower end opening of the manifold 209. The seal cap 219 is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220b is provided on the upper surface of the seal cap 219 as a sealing member that contacts the lower end of the manifold 209. Below the seal cap 219, a rotating mechanism 267 for rotating the boat 217, which will be described later, is installed. The rotating shaft 255 of the rotating mechanism 267 passes through the seal cap 219 and is connected to the boat 217. The rotating mechanism 267 is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be raised and lowered vertically by a boat elevator 115, which is installed outside the reaction tube 203 as a lifting mechanism. The boat elevator 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 seal cap 219, and functions as a device (preparation device) for preparing the substrate in the processing container. Furthermore, as shown in the modified example described later, when the substrate to be processed is manufactured in the processing chamber 201, that is, when a predetermined film is formed on the surface of the substrate in the processing chamber 201 to make it the substrate to be processed, the various parts of the processing apparatus used for forming this film (modifier supply system, second film-forming agent supply system, removal agent supply system, etc.) and the boat elevator 115 function as a preparation device.

[0024] Below the manifold 209, a shutter 219s is provided as a furnace opening cover that can airtightly close the lower end opening of the manifold 209 when the seal cap 219 is lowered and the boat 217 is removed from the processing chamber 201. The shutter 219s is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220c is provided on the upper surface of the shutter 219s as a sealing member that contacts the lower end of the manifold 209. The opening and closing operation of the shutter 219s (such as lifting and lowering or rotating) is controlled by the shutter opening and closing mechanism 115s.

[0025] The boat 217, acting as a substrate support, is configured to support multiple wafers 200, for example 25 to 200 wafers 200, in a horizontal position, aligned vertically with their centers aligned, and arranged in multiple layers, that is, with spacing between them. The boat 217 is made of a heat-resistant material such as quartz or SiC. Below the boat 217, multiple layers of insulating plates 218, also made of a heat-resistant material such as quartz or SiC, are supported. The boat 217 can also be considered as part of the preparation apparatus described above.

[0026] A temperature sensor 263 is installed inside the reaction tube 203 as a temperature detector. By adjusting the amount of power supplied to the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature inside the processing chamber 201 is adjusted to the desired temperature distribution. The temperature sensor 263 is installed along the inner wall of the reaction tube 203.

[0027] As shown in Figure 3, the controller 121, which is the control unit (control means), is configured as a computer equipped with a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, storage device 121c, and I / O port 121d. The RAM 121b, storage device 121c, and I / O port 121d are configured to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122, configured as, for example, a touch panel, is connected to the controller 121. An external storage device 123 can also be connected to the controller 121. The processing unit may be configured to have one control unit or multiple control units. That is, the control for performing the processing sequence described later may be performed using one control unit or using multiple control units. Furthermore, the multiple control units may be configured as a control system connected to each other by a wired or wireless communication network, and the control for performing the processing sequence described later may be performed by the entire control system. In this specification, the term "control unit" may refer to a single control unit, a plurality of control units, or a control system composed of a plurality of control units.

[0028] The storage device 121c is composed of, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. The storage device 121c contains, in a readable format, control programs that control the operation of the processing device, and process recipes that describe the procedures and conditions for the substrate processing described later. The process recipe functions as a program, combining the procedures in the substrate processing described later so that the controller 121 causes the processing device to execute them and obtain a predetermined result. Hereinafter, process recipes and control programs will be collectively referred to simply as "programs" (program products). Similarly, process recipes will be simply referred to as "recipes." In this specification, the term "program" may include only recipes, only control programs, or both. The RAM 121b is configured as a memory area (work area) where programs and data read by the CPU 121a are temporarily held.

[0029] I / O port 121d is connected to the MFCs 241a to 241h, valves 243a to 243h, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotary mechanism 267, boat elevator 115, shutter opening / closing mechanism 115s, etc.

[0030] The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read a recipe from the storage device 121c in response to input of operation commands from the input / output device 122. The CPU 121a is configured to control the flow rate adjustment operation of various substances (various gases) by the MFCs 241a to 241h, the opening and closing operation of valves 243a to 243h, the opening and closing operation of the APC valve 244 and the pressure adjustment operation of the APC valve 244 based on the pressure sensor 245, the starting and stopping of the vacuum pump 246, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the rotation and rotation speed adjustment operation of the boat 217 by the rotating mechanism 267, the raising and lowering operation of the boat 217 by the boat elevator 115, and the opening and closing operation of the shutter 219s by the shutter opening and closing mechanism 115s, in accordance with the contents of the read recipe.

[0031] The controller 121 can be configured by installing the above-mentioned program, which is recorded and stored in the external storage device 123, onto a computer. The external storage device 123 includes, for example, magnetic disks such as HDDs, optical disks such as CDs, and semiconductor memory such as USB memory and SSDs. The storage device 121c and the external storage device 123 are configured as computer-readable recording media. Hereinafter, these will be collectively referred to simply as recording media. In this specification, the term recording media may include only the storage device 121c, only the external storage device 123, or both. Note that the program may be provided to the computer using communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0032] (2) Processing steps Using the above-described processing apparatus, an example of a processing sequence for processing a substrate as one step in the manufacturing process (manufacturing method) of a semiconductor device, namely, a processing sequence for etching the surface of the wafer 200 as a substrate and a processing sequence for growing a film on the wafer 200 after etching, will be explained mainly using Figures 4(a) to 4(f). In the following explanation, the operation of each part constituting the processing apparatus is controlled by the controller 121. The processing apparatus will also be referred to as the substrate processing apparatus. The processing method will also be referred to as the substrate processing method.

[0033] In the processing sequence of this embodiment, (a) Step A, which prepares a wafer 200 having a nitrogen (N) containing film formed on its surface to be thicker than the originally required thickness T1 by a thickness T2, and an oxide film, (b) Step B, in which an oxide film on the surface of wafer 200 is etched using a substance X generated by a chemical reaction between an N-containing film and an F-containing substance by supplying an F-containing substance to wafer 200, To do so.

[0034] In the following example, after performing step B, (c) The case in which step C is further performed by supplying a first film-forming agent to the wafer 200 to form a film on the surface of the wafer 200 from which the oxide film has been etched will be described.

[0035] In this specification, the term "wafer" may refer to the wafer itself or to a laminate of a wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of the wafer" may refer to the surface of the wafer itself or to the surface of a predetermined film or the like formed on the wafer. In this specification, when it is stated that "a predetermined film is formed on the surface of the wafer," it may mean that the predetermined film is formed directly on the surface of the wafer itself or that the predetermined film is formed on a film or the like formed on the wafer. In this specification, the term "substrate" is used in the same sense as when the term "wafer" is used.

[0036] In this specification, the terms "agent" and "substance" include at least one of gaseous substances and liquid substances. Liquid substances include mist-like substances. That is, each of the F-containing substance, modifier, remover, first film-forming agent (first raw material, dopant agent), and second film-forming agent (second raw material, reactant) may contain a gaseous substance, a liquid substance such as a mist-like substance, or both.

[0037] (Step A) First, multiple wafers 200 are loaded (wafer charged) into the boat 217.

[0038] As described above, the surface of the wafer 200 is pre-formed with an N-containing film that is thicker than the originally required thickness T1 by a thickness T2, and an oxide film. As shown in Figure 4(a), the N-containing film on the surface of the wafer 200 includes a laminated film of a first N-containing film with a thickness T1 and a second N-containing film with a thickness T2.

[0039] As described later, in step B, the oxide film is etched and removed. In this process, the upper portion of the N-containing film with a thickness of T2 is removed, while the lower portion with a thickness of T1 is left. The first N-containing film corresponds to the lower portion with a thickness of T1 of the N-containing film, and is the necessary film of the N-containing film, i.e., the film that needs to remain on the wafer 200 in step B without reducing its thickness from T1. The second N-containing film corresponds to the upper portion with a thickness of T2 of the N-containing film, and is the excess (unnecessary) film of the N-containing film, i.e., the film that needs to be removed from the wafer 200 in step B. Note that the thickness T2 is predetermined so that the N-containing film can be removed in step B.

[0040] In this specification, the lower layer portion of the N-containing film with a thickness T1, which is the required layer, i.e., the first N-containing film with a thickness T1, will also be simply referred to as the first N-containing film. Furthermore, the upper layer portion of the N-containing film with a thickness T2, which is the excess layer, i.e., the second N-containing film with a thickness T2, will also be simply referred to as the second N-containing film.

[0041] The first and second N-containing films may each contain silicon (Si) as a semiconductor element, such as silicon nitride (SiN), silicon carbonitride (SiCN), silicon oxynitride (SiON), silicon oxycarbonitride (SiOCN), silicon boronitride (SiBCN), and silicon boronitride (SiBN). Furthermore, the first and second N-containing films may each contain metallic elements and N-containing films such as titanium nitride (TiN), tungsten nitride (WN), and aluminum nitride (AlN). These films may be identical or different in terms of material, composition, and constituent elements. For example, the first N-containing film may be a SiN film and the second N-containing film may be a SiN film. Alternatively, the first N-containing film may be a SiCN film and the second N-containing film may be a SiN film.

[0042] It is preferable to prepare the first and second N-containing films such that the etching resistance of the first N-containing film to the F-containing substance is higher than that of the second N-containing film to the F-containing substance. Furthermore, it is preferable to prepare the first and second N-containing films such that the etching resistance of the first N-containing film to the F-containing substance in at least the portion of the first N-containing film that is in contact with the second N-containing film is higher than that of the second N-containing film to the F-containing substance.

[0043] The oxide film may contain a silicon oxide film (SiO film). Furthermore, the oxide film may contain a silicon oxide film (SiO film) with a non-stoichiometric composition. x The material may contain at least one of the following: a film (where x is a real number less than 2) and a silicon oxide film (SiO2 film) of stoichiometric composition. Furthermore, the oxide film may contain at least one of the following: a native oxide film and a chemical oxide film. x The film and SiO2 film will collectively be referred to as SiO film below.

[0044] The oxide film substrate may include at least one of the following: a semiconductor element-containing substrate such as single-crystal Si; a semiconductor element-containing film such as silicon film (Si film), germanium film (Ge film), silicon-germanium film (SiGe film); a semiconductor element and N-containing film such as SiN film, SiCN film, SiON film, SiCN film, SiBCN film, SiBN film; a metal element and N-containing film such as TiN film, WN film, AlN film; a semiconductor element and O-containing film such as SiO film, silicon oxide carbide film (SiOC film); a metal element and O-containing film such as titanium oxide film (TiO film), hafnium oxide film (HfO film), zirconium oxide film (ZrO film), aluminum oxide film (AlO film); or a metal element-containing film such as tungsten (W film), molybdenum film (Mo film), or ruthenium film (Ru film).

[0045] After wafer charging is complete, the shutter 219s is moved by the shutter opening / closing mechanism 115s, opening the lower end opening of the manifold 209 (shutter open). Then, as shown in Figure 1, the boat 217 supporting the wafer 200 is lifted by the boat elevator 115 and loaded into the processing chamber 201 (boat loaded). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0046] Upon completion of the boat loading, the substrate to be processed, i.e., the wafer 200 having an N-containing film formed on its surface that is T2 thicker than the originally required thickness T1, and an oxide film, is prepared (placed) in the processing chamber 201.

[0047] (Pressure adjustment and temperature adjustment) After the boat loading is complete, the processing chamber 201, i.e., the space where the wafer 200 is located, is evacuated (reduced pressure exhaust) by a vacuum pump 246 to achieve the desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by a pressure sensor 245, and the APC valve 244 is feedback-controlled based on this measured pressure information. The wafer 200 inside the processing chamber 201 is also heated by a heater 207 to reach the desired processing temperature. At this time, the amount of power supplied to the heater 207 is feedback-controlled based on the temperature information detected by a temperature sensor 263 to ensure that the processing chamber 201 has the desired temperature distribution. The rotation of the wafer 200 by the rotation mechanism 267 is also started. The exhaust of the processing chamber 201, the heating of the wafer 200, and the rotation are all continued at least until the processing of the wafer 200 is completed.

[0048] (Step B) Subsequently, the F-containing substance is supplied to the wafer 200 in the processing chamber 201.

[0049] Specifically, valve 243a is opened, and the F-containing substance is allowed to flow into the gas supply pipe 232a. The F-containing substance's flow rate is adjusted by MFC 241a, and it is supplied into the processing chamber 201 via nozzle 249a and exhausted through exhaust port 231a. At this time, the F-containing substance is supplied to the wafer 200 from the side, and the wafer 200 is exposed to the F-containing substance (supply and exposure of F-containing substance). At this time, valves 243f to 243h may be opened to supply inert gas into the processing chamber 201 via nozzles 249a to 249c, respectively.

[0050] Under the processing conditions described later, by supplying an F-containing substance to the wafer 200, it becomes possible to generate substance X by chemically reacting the portion of the N-containing film with thickness T2, i.e., the second N-containing film, with the F-containing substance. Substance X is generated during the etching process of the second N-containing film by the F-containing substance. More specifically, substance X is generated by the decomposition of reaction products produced during the etching process of the second N-containing film by the F-containing substance. Substance X contains nitrogen (N) and hydrogen (H). By generating substance X in the processing chamber 201 to which the F-containing substance is supplied, it becomes possible to efficiently etch the oxide film on the surface of the wafer 200 using substance X.

[0051] For example, if the oxide film on the surface of wafer 200 contains silicon oxide (SiO2), the secondary N-containing film on the surface of wafer 200 contains silicon nitride (Si3N4), and the F-containing substance supplied into the processing chamber 201 contains hydrogen fluoride (HF), then under the conditions described later, the reaction shown in the following equation can be carried out.

[0052] Si3N4+16HF → 3(NH4)2SiF6+2H2 (NH4)2SiF6 → SiF4+2HF+2NH3 SiO2+4HF+4NH3→ SiF4+2H2O+4NH3

[0053] Specifically, on the surface of wafer 200, as shown in Figure 4(b), a chemical reaction occurs between the second N-containing film (Si3N4) and the F-containing substance (HF), generating a solid reaction product such as ammonium silicofluoride, i.e., ammonium hexafluorosilicate ((NH4)2SiF6). Furthermore, on the surface of wafer 200, as shown in Figure 4(c), this solid reaction product can be decomposed (e.g., by thermal decomposition) to generate a hydrogen nitride substance X, such as ammonia (NH3). By generating a substance X containing N and H, such as NH3, in the presence of the F-containing substance (HF), the etching reaction of the oxide film (SiO2) present on the surface of wafer 200 can be accelerated, as shown in Figure 4(d). In this step, by supplying the F-containing substance to wafer 200, the second N-containing film and the oxide film are etched in parallel, gradually thinning these films. Then, by continuing to supply the F-containing material to the wafer 200, the second N-containing film and the oxide film are removed, as shown in Figure 4(e), thereby exposing the surfaces of the first N-containing film and the substrate. In other words, for the N-containing film, it is possible to remove the portion with a thickness of T2 while leaving the portion with a thickness of T1. In the process of removing the oxide film with the F-containing material and material X, solid reaction products such as (NH4)2SiF6 may be generated again, but in this reaction system, the solid reaction products are immediately decomposed as soon as they are generated, and the above-mentioned reactions occur in a chain reaction. In other words, in this reaction system, the reaction, generation of solid reaction products, decomposition of solid reaction products, and etching occur repeatedly in a chain reaction, making it possible to suppress the solid reaction products from remaining as solids on the outermost surface of the oxide film that is to be etched.

[0054] According to this disclosure, as described above, it is possible to initiate the etching reaction without triggering it with a reaction between the F-containing substance (HF) and water (H2O). In other words, according to this disclosure, it is possible to initiate the etching reaction and etch the oxide film on the surface of the wafer 200 without the presence of H2O in the processing chamber 201 at the start of step B.

[0055] After removing the second N-containing film and the oxide film, valve 243a is closed to stop the supply of F-containing material into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any remaining gaseous material. At this time, valves 243f to 243h are opened to supply inert gas into the processing chamber 201 via nozzles 249a to 249c. The inert gas supplied from nozzles 249a to 249c acts as a purge gas, thereby purging the processing chamber 201.

[0056] The processing conditions when supplying the F-containing substance in step B are as follows: Processing temperature: Room temperature (25°C) to 200°C, preferably 50 to 175°C, more preferably 100 to 150°C, and even more preferably 120 to 150°C. Processing pressure: 10-3000 Pa, preferably 10-2000 Pa Processing time: 1 to 120 minutes, preferably 1 to 100 minutes F-containing substance supply flow rate: 0.5 to 3 slm, preferably 1 to 2 slm Inert gas supply flow rate (per gas supply pipe): 0-10 slm, preferably 1-5 slm Examples are given.

[0057] In this specification, numerical ranges such as "25~200°C" mean that the lower and upper limits are included within that range. For example, "25~200°C" means "25°C or more and 200°C or less." The same applies to other numerical ranges. In this specification, processing temperature means the temperature of the wafer 200 or the temperature inside the processing chamber 201, and processing pressure means the pressure inside the processing chamber 201. Processing time means the time during which the processing is continued. When 0 slm is included in the supply flow rate, 0 slm means the case in which the substance (gas) is not supplied. These also apply in the following explanations.

[0058] Here, if the processing temperature when supplying the F-containing material in step B is set below room temperature (25°C), the etching rate can be increased. However, if other processing such as film deposition is performed at least before or after the etching process, the time required to change the processing temperature between the etching process and the other processing (heating up time and / or cooling down time) may become too long, which can reduce productivity.

[0059] By setting the processing temperature to room temperature (25°C) or higher, it is possible to maintain a high etching rate while shortening the time required to change processing temperatures between processes, thereby suppressing a decrease in productivity. By setting the processing temperature to 50°C or higher, it is possible to maintain a high etching rate while further shortening the time required to change processing temperatures between processes, thereby further suppressing a decrease in productivity. By setting the processing temperature to 100°C or higher, it is possible to maintain a high etching rate while significantly shortening the time required to change processing temperatures between processes, thereby significantly improving productivity. By setting the processing temperature to 120°C or higher, it is possible to maintain a high etching rate while further significantly shortening the time required to change processing temperatures between processes, thereby significantly improving productivity.

[0060] Furthermore, while setting the processing temperature above 200°C can significantly reduce the time required to change processing temperatures between different processes, it can also lead to an excessively low etching rate, resulting in reduced productivity.

[0061] By setting the processing temperature to 200°C or lower, it is possible to suppress the decrease in etching rate while maintaining a significant reduction in the time required to change processing temperatures between processes, thereby suppressing the decrease in productivity. By setting the processing temperature to 175°C or lower, it is possible to further suppress the decrease in etching rate while maintaining a significant reduction in the time required to change processing temperatures between processes, thereby suppressing the decrease in productivity. By setting the processing temperature to 150°C or lower, it is possible to significantly suppress the decrease in etching rate while maintaining a significant reduction in the time required to change processing temperatures between processes, thereby suppressing the decrease in productivity.

[0062] Based on the above, it is desirable that the processing temperature described above be between room temperature (25°C) and 200°C, preferably between 50°C and 175°C, more preferably between 100°C and 150°C, and even more preferably between 120°C and 150°C.

[0063] As the F-containing substance, for example, a substance containing hydrogen (H), such as hydrogen fluoride (HF), can be used. Alternatively, as the F-containing substance, for example, fluorine (F2), nitrogen trifluoride (NF3), chlorine trifluoride (ClF3), chlorine fluoride (ClF), etc., can be used. One or more of these can be used as the F-containing substance.

[0064] As the inert gas, nitrogen (N2) gas, argon (Ar) gas, helium (He) gas, neon (Ne) gas, xenon (Xe) gas, and other noble gases can be used. One or more of these can be used as the inert gas. This also applies to each of the steps described later.

[0065] (Step C) After step B is completed, the output of the heater 207 is adjusted so that the temperature of the wafer 200 reaches a predetermined processing temperature, which will be described later. Then, the first raw material as the first film-forming agent is supplied to the wafer 200 in the processing chamber 201.

[0066] Specifically, valve 243b is opened and the first raw material flows into the gas supply pipe 232b. The flow rate of the first raw material is adjusted by MFC 241b and supplied into the processing chamber 201 via nozzle 249b, and exhausted from exhaust port 231a. At this time, the first raw material is supplied to the wafer 200 from the side of the wafer 200, and the wafer 200 is exposed to the first raw material (supply and exposure of the first raw material). At this time, valves 243f to 243h may be opened to supply inert gas into the processing chamber 201 via nozzles 249a to 249c, respectively.

[0067] By supplying the first raw material to the wafer 200 under the processing conditions described later, it becomes possible to form a predetermined film on the surface of the wafer 200 from which the second N-containing film and the oxide film have been removed, as shown in Figure 4(f), i.e., on the exposed surface of the first N-containing film and the substrate. When the substance described later is used as the first raw material, it becomes possible to form a Si film as a film on the surface of the wafer 200.

[0068] After forming a predetermined film on the surface of the wafer 200 from which the second N-containing film and oxide film have been removed, the valve 243b is closed to stop the supply of the first raw material into the processing chamber 201. Then, the processing chamber 201 is purged using the same processing procedure as in step B.

[0069] The processing conditions when supplying the first raw material as the first film-forming agent in step C are as follows: Processing temperature: 500-650°C, preferably 550-600°C Processing pressure: 4-200 Pa, preferably 1-120 Pa Processing time: 10-120 minutes, preferably 20-60 minutes First raw material supply flow rate: 0.1 to 5 slm, preferably 0.2 to 3 slm Inert gas supply flow rate (per gas supply pipe): 0-10 slm, preferably 0.1-5 slm Examples are given.

[0070] For example, the first raw material is monosilane (SiH4), disilane (Si2H6), trisilane (Si3H8), tetrasilane (Si4H 10 Silicon hydride such as ) can be used.

[0071] (After-purge and return to atmospheric pressure) After step C is completed, inert gas is supplied as a purge gas into the processing chamber 201 from nozzles 249a to 249c and exhausted from exhaust port 231a. This purges the processing chamber 201, removing any remaining gases and reaction by-products (after-purge). Subsequently, the atmosphere inside the processing chamber 201 is replaced with inert gas (inert gas replacement), and the pressure inside the processing chamber 201 is returned to atmospheric pressure (atmospheric pressure return).

[0072] (Boat unloading) Subsequently, the seal cap 219 is lowered by the boat elevator 115, opening the lower end of the manifold 209. Then, the processed wafer 200, supported by the boat 217, is unloaded from the lower end of the manifold 209 to the outside of the reaction tube 203 (boat unloading). After boat unloading, the shutter 219s is moved, and the lower end opening of the manifold 209 is sealed by the shutter 219s via the O-ring 220c (shutter close). After that, the processed wafer 200 is removed from the boat 217 (wafer discharge).

[0073] The processing step in one aspect of this disclosure is thus completed.

[0074] Furthermore, steps B and C described above are preferably performed in the same processing chamber (in situ). Performing the series of processes in situ ensures that the wafer 200 is not exposed to the atmosphere during the process, and allows for consistent and stable processing while the wafer 200 remains under vacuum. In addition, this embodiment uses an F-containing substance supply system, a first raw material supply system, and an inert gas supply system, but does not use a second raw material supply system, a dopant agent supply system, a modifier supply system, a reactant supply system, or a removal agent supply system, so these supply systems can be omitted.

[0075] (3) Effects of this embodiment According to this embodiment, one or more of the following effects can be obtained.

[0076] (a) Step A is performed to prepare a substrate having an N-containing film formed on its surface that is T2 thicker than the originally required thickness T1, and an oxide film. Then, step B is performed to supply an F-containing substance to the substrate. This makes it possible to etch the oxide film on the surface of the substrate using substance X generated by a chemical reaction between the second N-containing film and the F-containing substance. The action of substance X promotes the etching reaction of the oxide film, making etching more efficient.

[0077] Furthermore, the use of substance X makes it possible to raise the processing temperature when etching the oxide film. This allows the etching temperature to be brought closer to the processing temperature of other processes, such as film deposition, when other processes are performed at least before or after the etching process. This reduces the time required to change the processing temperature between the etching process and other processes, i.e., at least one of the heating time and cooling time, thereby increasing productivity.

[0078] Furthermore, by increasing the processing temperature during etching, it becomes possible to decompose and remove solid reaction products generated during the reaction process while the F-containing material is still being supplied. This prevents the solid reaction products generated during the reaction process from remaining on the outermost surface of the oxide film being etched, i.e., from remaining in a solid state and preventing further reaction from proceeding. In addition, this eliminates the need to separately raise the processing temperature to sublimate the solid reaction products after stopping the supply of the F-containing material, thereby increasing productivity.

[0079] Furthermore, when etching oxide films on the surfaces of multiple substrates, substance X can be generated on the surface of each substrate, making it possible to improve the uniformity of the oxide film etching process between substrates.

[0080] Furthermore, there is no need to set up a separate supply line for substance X, which reduces equipment costs. Also, by eliminating the supply line for substance X, the supply system can be simplified, reducing the effort and cost of supply system maintenance. In addition, there is no need to place components for generating substance X in-situ (such as dummy wafers with an N-containing film formed on their surface) near the substrate, and there is no need to reduce the number of substrates processed at one time. This helps to avoid an increase in processing costs.

[0081] Furthermore, a laminated film consisting of a first N-containing film and a second N-containing film is pre-formed on the surface of the substrate prepared in step A. This eliminates the need for a modifier supply system, a removal agent supply system, a reactant supply system, etc., thereby simplifying the supply system and reducing the maintenance effort and cost of the supply system.

[0082] (b) The second N-containing film contains Si, and the F-containing material contains H. This makes it possible to effectively obtain the effects described above. Alternatively, the second N-containing film contains a SiN film, and the F-containing material contains HF. This makes it possible to effectively obtain the effects described above.

[0083] (c) Substance X contains N and H. Substance X is also produced during the etching of the second N-containing film by the F-containing substance. Substance X is also produced by the decomposition of reaction products generated during the etching of the second N-containing film by the F-containing substance. The above effects can be effectively obtained by at least one of these.

[0084] (d) The oxide film includes an SiO film. The oxide film also includes at least one of a non-stoichiometric SiO film and a stoichiometric SiO film. The oxide film also includes at least one of a native oxide film and a chemical oxide film. At least one of these makes it possible to effectively obtain the effects described above.

[0085] (e) After step B, step C is performed. This makes it possible to reduce the impurity concentration (oxygen concentration, etc.) at the interface between the substrate and the film formed in step C.

[0086] (f) Of the N-containing films, the etching resistance of the first N-containing film to the F-containing material is higher than that of the second N-containing film to the F-containing material. Also, of the N-containing films, the etching resistance of the first N-containing film to the F-containing material in at least the portion in contact with the second N-containing film is higher than that of the second N-containing film to the F-containing material. At least one of these conditions makes it possible to suppress over-etching of the N-containing film in step B, remove the portion of the N-containing film with a thickness of T2, and leave the portion with a thickness of T1 with high precision.

[0087] (g) The effects described above can also be obtained when a predetermined substance is arbitrarily selected from the various F-containing substances, various first film-forming agents (first raw materials), and various inert gases described above.

[0088] (4) Variations The processing sequence in this embodiment can be modified as shown in the following examples. These modifications can be combined in any way. Unless otherwise specified, the processing procedures and conditions in each step of each modification can be the same as those in each step of the processing sequence described above.

[0089] (Variation 1) In step A, a second N-containing film with a thickness T2 may be formed on a first N-containing film with a thickness T1 that has been pre-formed on the surface of the wafer 200.

[0090] In this case, in step A, (a1) Step A1 involves supplying a modifier to the wafer 200 to adsorb inhibitors contained in the modifier onto the surface of the oxide film, (a2) Step A2 involves supplying a second film-forming agent to a wafer 200 on which an inhibitor has been adsorbed on the surface of an oxide film, thereby forming an N-containing film on the surface of the wafer 200, which includes a laminated film comprising a first N-containing film with a thickness T1 and a second N-containing film with a thickness T2. It is possible to do so.

[0091] The following describes step A of this modified example, mainly with reference to Figures 5(a) to 5(d).

[0092] First, the wafer 200 to be processed is prepared in the processing chamber 201 using the same processing procedure as described above for wafer charging and boat loading. As shown in Figure 5(a), in this modified example, a first N-containing film with a thickness T1 and an oxide film are pre-formed on the surface of the wafer 200. The second N-containing film is not formed on the first N-containing film. The surface of the first N-containing film is exposed.

[0093] (Step A1) After the temperature and pressure in the processing chamber 201 have been adjusted, the modifier is supplied to the wafer 200 in the processing chamber 201.

[0094] Specifically, valve 243d is opened, and the reforming agent is allowed to flow into the gas supply pipe 232d. The reforming agent's flow rate is regulated by MFC 241d and supplied into the processing chamber 201 via gas supply pipe 232a and nozzle 249a, and exhausted from exhaust port 231a. At this time, the reforming agent is supplied to the wafer 200 from the side of the wafer 200, and the wafer 200 is exposed to the reforming agent (reforming agent supply, exposure). At this time, valves 243f to 243h may be opened to supply inert gas into the processing chamber 201 via nozzles 249a to 249c, respectively.

[0095] By supplying a modifier to the wafer 200 under the processing conditions described later, inhibitors contained in the modifier are adsorbed onto the surface of the oxide film, as shown in Figure 5(b), making it possible to selectively form an inhibitor layer on the surface of the oxide film, rather than the oxide film or the first N-containing film. The inhibitors include at least a part of the molecular structure of the molecules constituting the modifier, i.e., residues derived from the modifier contained in the modifier. The inhibitor layer is an aggregate of inhibitors and includes a high-density layer that densely covers the surface of the oxide film. In step A2 described later, the inhibitor layer functions to suppress or inhibit (block) the progress of the film formation reaction on the oxide film. The above-mentioned effect of the inhibitor layer is also called the inhibitor effect (film formation suppression effect, film formation inhibition effect).

[0096] In this disclosure, expressions such as "a layer is selectively formed on the first surface of the two surfaces" refer to the relative degree to which a layer is formed on each surface. That is, this expression means that a layer is formed on the first surface in such a way that the degree to which a layer is formed on the second surface is greater than the degree to which a layer is formed on the second surface. In other words, the expression "selectively" in this disclosure means that treatment on one surface is given priority over treatment on another surface. This point is also true in the following explanation.

[0097] After forming an inhibitor layer on the surface of the oxide film, the valve 243d is closed to stop the supply of the modifier into the treatment chamber 201. Then, the treatment chamber 201 is purged using the same treatment procedure as in step B of the above embodiment.

[0098] The processing conditions when supplying the modifier in step A1 are as follows: Processing temperature: Room temperature (25°C) to 500°C, preferably room temperature to 250°C Processing pressure: 1 to 2000 Pa, preferably 10 to 1000 Pa Processing time: 1 to 3600 seconds, preferably 5 to 300 seconds Modifier supply flow rate: 0.001 to 10 slm, preferably 0.1 to 0.5 slm Inert gas supply flow rate (per gas supply pipe): 0-20 slm Examples are given.

[0099] As modifiers, for example, organic substances containing at least one of hydrocarbon groups and amino groups, and / or inorganic substances containing halogens can be used. When using both substances, it is preferable to first supply the organic substance, then perform a purge, and then supply the inorganic substance. When using the substances exemplified below, the surface of the oxide film is terminated with hydrocarbon groups such as alkyl groups, H, Cl, F, etc., and hydrocarbon group terminations such as alkyl group terminations, H terminations, Cl terminations, F terminations, etc. function as inhibitors.

[0100] Examples of modifiers include (dipropylamino)trimethylsilane ((C3H7)2NSi(CH3)3), (dibutylamino)trimethylsilane ((C4H9)2NSi(CH3)3), (dimethylamino)trimethylsilane ((CH3)2NSi(CH3)3), (diethylamino)triethylsilane ((C2H5)2NSi(C2H5)3), (dimethylamino)triethylsilane ((CH3)2NSi(C2H5)3), and (diethylamino)trimethylsilane ((C2 (H5)2NSi(CH3)3), (trimethylsilyl)amine ((CH3)3SiNH2), (triethylsilyl)amine ((C2H5)3SiNH2), (dimethylamino)silane ((CH3)2NSiH3), (diethylamino)silane ((C2H5)2NSiH3), (dipropylamino)silane ((C3H7)2NSiH3), (dibutylamino)silane ((C4H9)2NSiH3), hydrogen chloride (HCl), chlorine (Cl2), ClF3, F2, etc. can be used. One or more of these can be used as modifiers.

[0101] (Step A2) After step A1 is completed, step A2a is performed to supply a second raw material as a second film-forming agent to the wafer 200 in the processing chamber 201, and step A2b is performed to supply a reactant as a second film-forming agent.

[0102] [Step A2a] In this step, the second raw material is supplied to the wafer 200 in the processing chamber 201 using the same processing procedure as in step C of the above-described embodiment.

[0103] By supplying the second raw material to the wafer 200 under the processing conditions described later, it is possible to suppress the adsorption of at least a portion of the molecular structure of the molecules constituting the second raw material onto the surface of the oxide film, while promoting the selective adsorption of at least a portion of the molecular structure of the molecules constituting the second raw material onto the surface of the first N-containing film. As a result, a first layer can be formed on the surface of the first N-containing film in which at least a portion of the molecular structure of the molecules constituting the second raw material is selectively (preferentially) adsorbed.

[0104] After forming the first layer on the surface of the first N-containing film, the supply of the second raw material is stopped. Then, the processing chamber 201 is purged using a processing procedure similar to the purging in step B of the above embodiment.

[0105] As a second raw material, for example, chlorosilanes can be used, such as monochlorosilane (SiH3Cl), dichlorosilane (SiH2Cl2), trichlorosilane (SiHCl3), tetrachlorosilane (SiCl4), hexachlorodisilane (Si2Cl6), and octachlorotrisilane (Si3Cl8), in which a chloro group (Cl) is bonded to Si. Alternatively, as a second raw material, aminosilanes can be used, such as tetrakis(dimethylamino)silane (Si[N(CH3)2]4), tris(dimethylamino)silane (Si[N(CH3)2]3H), and bis(diethylamino)silane (Si[N(C2H5)2]2H2), in which H and an amino group are bonded to Si. One or more of these can be used as the second raw material.

[0106] The processing conditions when supplying the second raw material as the second film-forming agent in step A2a are as follows: Processing temperature: Room temperature (25°C) to 700°C, preferably 350 to 550°C Processing pressure: 1 to 2000 Pa, preferably 1 to 1333 Pa Processing time: 1 to 180 seconds, preferably 10 to 120 seconds Second raw material supply flow rate: 0.001 to 2 slm, preferably 0.01 to 1 slm Inert gas supply flow rate (per gas supply pipe): 0-10 slm, preferably 0.1-5 slm Examples are given.

[0107] [Step A2b] In this step, the reactant is supplied to the wafer 200 in the processing chamber 201.

[0108] Specifically, valve 243e is opened, and the reactant is allowed to flow into the gas supply pipe 232e. The reactant's flow rate is regulated by MFC 241e and supplied into the processing chamber 201 via gas supply pipe 232b and nozzle 249b, and exhausted from exhaust port 231a. At this time, the reactant is supplied to the wafer 200 from the side, and the wafer 200 is exposed to the reactant (reactant supply, exposure). At this time, valves 243f to 243h may be opened to supply inert gas into the processing chamber 201 via nozzles 249a to 249c, respectively.

[0109] By supplying the reactant to the wafer 200 under the processing conditions described later, it becomes possible to alter (nitride) at least a portion of the first layer formed on the surface of the first N-containing film in step A2a. As a result, a second layer is formed on the surface of the first N-containing film, in which the first layer has been selectively (preferentially) nitrided.

[0110] After forming a second layer on the surface of the first N-containing film, the valve 243e is closed to stop the supply of the reactant into the processing chamber 201. Then, the processing chamber 201 is purged using a processing procedure similar to the purging in step B of the above embodiment.

[0111] As a reactant, for example, a nitriding agent (nitriding gas) can be used. As a nitriding agent, for example, N and H-containing substances such as ammonia (NH3), diazene (N2H2), hydrazine (N2H4), and N3H8, i.e., hydrogen nitride, can be used. One or more of these can be used as reactants.

[0112] The processing conditions when supplying the reactant as the second film-forming agent in step A2b are as follows: Processing pressure: 1 to 4000 Pa, preferably 1 to 1333 Pa Reactant supply flow rate: 0.01 to 20 slm, preferably 0.01 to 10 slm This is an example. Other processing conditions can be the same as the processing conditions in step A2a.

[0113] [Perform the prescribed number of times] By performing the cycle including steps A2a and A2b described above a predetermined number of times (n times, where n is 1 or an integer of 2 or more), it becomes possible to form a second N-containing film with a thickness T2 on the first N-containing film, as shown in Figure 5(c). It is preferable to repeat the above cycle multiple times. That is, it is preferable to make the thickness of the second layer formed per cycle thinner than the desired film thickness, and to repeat the above cycle multiple times until the thickness of the second N-containing film formed by stacking the second layers reaches the predetermined thickness T2.

[0114] (Step A3) After step A2 is completed, the removal agent is supplied to the wafer 200 in the processing chamber 201 using the same processing procedure as in step A2b described above.

[0115] By supplying a removal agent to the wafer 200 under the processing conditions described later, it becomes possible to remove and disable at least one of the inhibitor layers remaining on the surface of the oxide film, as shown in Figure 5(d). Figure 5(d) shows the case where the inhibitor layer remaining on the surface of the oxide film is removed.

[0116] Subsequently, the supply of the removal agent is stopped. Then, the treatment chamber 201 is purged using a treatment procedure similar to the purging in step B of the above embodiment.

[0117] The processing conditions when supplying the removal agent in step A3 are as follows: Processing temperature: 200-1000°C, preferably 400-700°C Processing pressure: 1~120000Pa Processing time: 1-18000 seconds Removal agent supply flow rate: 0-50 slm RF power: 0~10000W The following are examples. RF power refers to the power applied to generate plasma when performing plasma treatment using a removal agent. Also, a removal agent supply flow rate of 0 slm means the case in which no removal agent is supplied. In other words, without supplying a removal agent, it is also possible to remove and deactivate at least one of the inhibitor layers remaining on the surface of the oxide film by, for example, using thermal energy from heating.

[0118] Examples of scavenging agents include oxygen (O2), ozone (O3), H2O, hydrogen peroxide (H2O2), hydrogen (H2) + O2, H2 + O3, deuterium (D2) + O2, D2 + O3, nitrous oxide (N2O), nitric oxide (NO), nitrogen dioxide (NO2), carbon dioxide (CO2), carbon monoxide (CO), etc., as well as N and H-containing substances such as NH3, N2H2, N2H4, etc., reducing substances such as H2, D2, etc., inert gases such as He gas, Ar gas, N2 gas, etc., or mixtures thereof.

[0119] In this specification, the joint mention of two substances, such as "H2 + O2," refers to a mixture of H2 and O2. When supplying a mixture, the two substances may be mixed (premixed) in the supply pipe before being supplied to the processing chamber 201, or the two substances may be supplied separately to the processing chamber 201 from different supply pipes and then mixed (postmixed) in the processing chamber 201.

[0120] With the above steps completed, step A of this modified example is finished. After that, steps B and C of the above-described embodiment can be performed.

[0121] In this modified example, the same effects as in the above-described embodiment can be obtained. Furthermore, according to this modified example, by performing steps A1 and A2, it becomes possible to selectively form a second N-containing film with a thickness T2 on a first N-containing film with a thickness T1 that was previously formed on the surface of the substrate. This makes it possible to efficiently prepare a wafer 200 having an N-containing film formed on the surface that is thicker by T2 than the originally required thickness T1, and an oxide film.

[0122] Furthermore, according to this modified method, after performing steps A1 and A2, step A3 is performed to remove and disable at least one of the inhibitor layer remaining on the surface of the oxide film. This prevents the etching of the oxide film in step B from being hindered by the inhibitor layer remaining on the surface of the oxide film. As a result, the etching of the oxide film in step B can be started smoothly and performed efficiently.

[0123] Figure 5(d) shows the case where all (complete) inhibitor layers remaining on the surface of the oxide film are removed in step A3. However, if the inhibitory effect of the inhibitor layer has been sufficiently reduced or neutralized after the completion of step A2, it is not necessarily required to completely remove the inhibitor layer in step A3. Furthermore, if no inhibitor layer remains on the surface of the oxide film after the completion of step A2, or if the inhibitory effect of any remaining inhibitor layer on the surface of the oxide film has been sufficiently reduced or neutralized, it is possible to omit step A3.

[0124] In other words, in this modified example, it is also possible to perform step B with the inhibitor adsorbed on the surface of the oxide film in step A1 remaining. In this case, the inhibitor remaining on the surface of the oxide film is removed along with the oxide film when the oxide film is etched in step B. In this way, by minimizing the amount of inhibitor layer removed, or by omitting the removal of the inhibitor layer, it is possible to shorten or eliminate the time required for the removal of the inhibitor layer, thereby increasing the productivity of substrate processing.

[0125] Furthermore, in step A2 of this modified example, processing conditions can be appropriately selected so that the etching resistance of the second N-containing film to the F-containing substance is lower than that of the first N-containing film to the F-containing substance. For example, the processing temperature when forming the second N-containing film can be set lower than the processing temperature when forming the first N-containing film. This makes it possible to make the second N-containing film less pure and less dense than the first N-containing film. In other words, the second N-containing film can be made into a film with many impurities and low density. As a result, it becomes possible to make the etching resistance of the second N-containing film to the F-containing substance lower than that of the first N-containing film to the F-containing substance.

[0126] Furthermore, in step A2 of this modified example, the processing procedure in step A2 can be arranged so that the etching resistance of the F-containing substance in at least the portion of the first N-containing film that is in contact with the second N-containing film is higher than the etching resistance of the F-containing substance in the second N-containing film. For example, heat treatment (thermal nitriding, annealing, etc.) or plasma treatment (plasma nitriding, etc.) can be performed on the pre-formed first N-containing film before forming the second N-containing film. This makes at least the surface of the first N-containing film higher in purity, higher in density (densification), and harder than the second N-containing film. As a result, the etching resistance of the F-containing substance in at least the portion of the first N-containing film that is in contact with the second N-containing film is higher than the etching resistance of the F-containing substance in the second N-containing film, and the surface of the first N-containing film can be given the function of an etching stopper layer. Alternatively, for example, an etching stopper layer having higher etching resistance than the first N-containing film can be formed on the pre-formed first N-containing film before forming the second N-containing film. Furthermore, if the formation of the etching stopper layer involves heat treatment or plasma treatment, it can be considered one of the heat treatments or plasma treatments for the first N-containing film.

[0127] By using at least one of these methods, it becomes possible to suppress over-etching of the N-containing film in step B, remove the portion of the N-containing film with a thickness of T2, and leave the portion with a thickness of T1, with high precision.

[0128] Furthermore, the processing conditions for heat treatment or plasma treatment of the first N-containing film in step A2 are as follows: Processing temperature: Room temperature (25°C) to 800°C, preferably 300 to 700°C Processing pressure: 1 to 5000 Pa, preferably 1 to 3000 Pa Processing time: 1 to 300 seconds, preferably 1 to 200 seconds Reactant supply flow rate: 0-20 slm, preferably 0.01-10 slm Inert gas supply flow rate: 0-20 slm RF power: 0~10000W Examples include the following. As reactants, for example, substances similar to the various nitrides exemplified above can be used.

[0129] (Modification 2) In step A, a laminated film consisting of a first N-containing film with a thickness T1 and a second N-containing film with a thickness T2 may be formed on the surface of a wafer 200 that does not have an N-containing film formed on it. In this case, step A can be performed in the same way as in the first modification, by supplying a modifier to the wafer 200 in step A1 and supplying a second film-forming agent to the wafer 200 in step A2.

[0130] The following describes step A of this modified example, mainly with reference to Figures 6(a) to 6(d).

[0131] First, the wafer 200 to be processed is prepared in the processing chamber 201 using the same processing procedure as described above for wafer charging and boat loading. As shown in Figure 6(a), in this modified example, an oxide film is already formed on the surface of the wafer 200, and neither the first nor the second N-containing film is formed. The surface of the wafer 200 is partially exposed, and this partially exposed surface of the wafer 200 will hereafter be referred to as the exposed surface of the wafer 200.

[0132] (Step A1) After the temperature and pressure in the processing chamber 201 have been adjusted, the modifier is supplied to the wafer 200 in the processing chamber 201 using the same processing procedure and conditions as in step A1 of Modification 1. As a result, as shown in Figure 6(b), the inhibitor contained in the modifier is selectively adsorbed onto the surface of the oxide film, specifically on the surface of the oxide film, and an inhibitor layer is formed, which is the only surface of the oxide film that is exposed on the wafer 200.

[0133] After forming an inhibitor layer on the surface of the oxide film, the supply of the modifier is stopped. Then, the treatment chamber 201 is purged using a treatment procedure similar to the purging in step B of the above embodiment.

[0134] (Step A2) After step A1 is completed, a laminated film consisting of a first N-containing film with a thickness T1 and a second N-containing film with a thickness T2 is formed on the exposed surface of the wafer 200, as shown in Figure 6(c).

[0135] The first and second N-containing films can each be formed by the same processing procedure and conditions as in step A2 of Modification 1. That is, by performing the cycle including steps A2a and A2b of Modification 1 a predetermined number of times (n1 times, where n1 is 1 or an integer of 2 or more), a first N-containing film with a thickness T1 can be formed on the exposed surface of the wafer 200. Subsequently, by performing this cycle a predetermined number of times (n2 times, where n2 is 1 or an integer of 2 or more), a second N-containing film with a thickness T2 can be formed on the first N-containing film. Similar to Modification 1, it is preferable to repeat each of these cycles multiple times.

[0136] (Step A3) After step A2 is completed, the removal agent is supplied to the wafer 200 in the processing chamber 201 using the same processing procedure as in step A3 of Modification 1. This makes it possible to remove and disable at least one of the inhibitor layers remaining on the surface of the oxide film, as shown in Figure 6(d). Figure 6(d) shows the case where the inhibitor layer remaining on the surface of the oxide film is removed.

[0137] With the above steps completed, step A of this modified example is finished. After that, steps B and C of the above-described embodiment can be performed.

[0138] In this modified example, the same effects as those described above and in Modified Example 1 can be obtained. Furthermore, according to this modified example, by performing steps A1 and A2, it becomes possible to selectively form an N-containing film on the exposed surface of the substrate, which includes a laminated film comprising a first N-containing film with a thickness T1 and a second N-containing film with a thickness T2. This makes it possible to selectively form (prepare) an N-containing film that is formed to be thicker by T2 than the originally required thickness T1 at a desired location on the surface of the substrate.

[0139] Furthermore, according to this modified example, as in Modified Example 1, after performing steps A1 and A2, step A3 is carried out. This makes it possible to smoothly start and efficiently perform the etching of the oxide film in step B.

[0140] Furthermore, similar to Modification 1, after the completion of step A2, depending on the situation, the amount of inhibitor layer removed in step A3 can be minimized, or step A3 can be omitted. In other words, it is possible to perform step B with the inhibitor adsorbed on the surface of the oxide film in step A1 remaining. In this case, the productivity of substrate processing can be increased.

[0141] Furthermore, in step A2 of this modified example, processing conditions can be appropriately selected so that the etching resistance of the first N-containing film to the F-containing substance is higher than that of the second N-containing film to the F-containing substance. For example, the processing temperature when forming the first N-containing film can be set higher than the processing temperature when forming the second N-containing film. Specifically, for example, the processing temperature when forming the first N-containing film can be set to 630°C or higher and 700°C or lower, and the processing temperature when forming the second N-containing film can be set to 500°C or higher and less than 630°C. This makes the first N-containing film more pure, denser, and harder than the second N-containing film. In other words, the first N-containing film can be made into a film with fewer impurities, higher density, and harder. As a result, it becomes possible to make the etching resistance of the first N-containing film to the F-containing substance higher than that of the second N-containing film to the F-containing substance.

[0142] Furthermore, in step A2 of this modified example, the processing procedure in step A2 can be arranged so that the etching resistance of the F-containing substance in at least the portion of the first N-containing film that is in contact with the second N-containing film is higher than the etching resistance of the F-containing substance in the second N-containing film. For example, after forming the first N-containing film and before forming the second N-containing film, the first N-containing film can be subjected to heat treatment (thermal nitriding, annealing, etc.) or plasma treatment (plasma nitriding, etc.) under the same processing conditions as shown in Modified Example 1. This makes at least the surface of the first N-containing film more pure, denser (more compact), and harder than the second N-containing film. As a result, the etching resistance of the F-containing substance in at least the portion of the first N-containing film that is in contact with the second N-containing film is higher than the etching resistance of the F-containing substance in the second N-containing film, and the surface of the first N-containing film can be given the function of an etching stopper layer. Furthermore, for example, an etching stopper layer having higher etching resistance than the first N-containing film can be formed on the first N-containing film before forming the second N-containing film. Note that the formation of the etching stopper layer, if accompanied by heat treatment or plasma treatment, can be considered a type of heat treatment or plasma treatment for the first N-containing film.

[0143] By using at least one of these methods, it becomes possible to suppress over-etching of the N-containing film in step B, remove the portion of the N-containing film with a thickness of T2, and leave the portion with a thickness of T1, with high precision.

[0144] (Variation 3) In step B, the supply conditions for the F-containing substance, that is, the processing conditions when supplying the F-containing substance to the wafer 200, may be changed in multiple stages, for example, in two stages.

[0145] For example, in step B, the supply flow rate of the F-containing substance to the wafer 200, the supply flow rate of the inert gas, the concentration (partial pressure) of the F-containing substance, the dilution ratio of the F-containing substance, etc., may be changed in multiple stages. For example, in the latter half or final part of step B, the supply flow rate of the F-containing substance may be made lower than the supply flow rate of the F-containing substance up to that point. Alternatively, for example, in the latter half or final part of step B, the supply flow rate of the inert gas may be made higher than the supply flow rate of the inert gas up to that point. Alternatively, for example, in the latter half or final part of step B, the dilution ratio of the F-containing substance may be made higher than the dilution ratio up to that point, thereby lowering the concentration (partial pressure) of the F-containing substance to a lower level than the concentration (partial pressure) of the F-containing substance up to that point.

[0146] For example, by setting the inert gas supply flow rate in step B to a predetermined flow rate of 0.5 slm to 10 slm, and lowering the F-containing substance supply flow rate in the latter half or final part of step B compared to the F-containing substance supply flow rate up to that point, either of these can be achieved. Alternatively, for example, by setting the F-containing substance supply flow rate in step B to a predetermined flow rate of 0.5 slm to 3 slm, and highering the inert gas supply flow rate in the latter half or final part of step B compared to the inert gas supply flow rate up to that point, either of these can be achieved. Alternatively, for example, by lowering the F-containing substance supply flow rate in the latter half or final part of step B compared to the F-containing substance supply flow rate up to that point, and highering the inert gas supply flow rate in the latter half or final part of step B compared to the inert gas supply flow rate up to that point, either of these can be achieved.

[0147] In this modified example, the same effects as those in the above-described embodiment can be obtained. Furthermore, according to this modified example, in the latter half or final stages of step B, the reactivity between the F-containing material and the N-containing film can be reduced compared to the reactivity up to that point, and the etching rate can be reduced compared to the etching rate up to that point. In other words, according to this modified example, in step B, the reactivity between the F-containing material and the N-containing film can be reduced in multiple stages, and the etching rate can be reduced in multiple stages. This makes it possible to suppress over-etching of the N-containing film and remove the portion of the N-containing film with a thickness of T2 while leaving the portion with a thickness of T1 with high precision. In this case, by making the etching resistance of the first N-containing film to the F-containing material higher than that of the second N-containing film to the F-containing material, or by making the etching resistance of the first N-containing film to the F-containing material in at least the portion in contact with the second N-containing film higher than that of the second N-containing film to the F-containing material, it becomes possible to remove the portion of the N-containing film with a thickness of T2 while leaving the portion with a thickness of T1 with even higher precision.

[0148] <Other aspects of this disclosure> The aspects of this disclosure have been specifically described above. However, this disclosure is not limited to the aspects described above and can be modified in various ways without departing from its essence.

[0149] For example, in step B of the above-described embodiment, the F-containing gas may be supplied to the processing chamber intermittently, i.e., in a pulsed manner. For example, the supply of F-containing gas to the processing chamber and the purging and / or vacuuming of the processing chamber may be performed alternately a predetermined number of times (m times, where m is 1 or an integer of 2 or more). In this case as well, the same effects as in the above-described embodiment can be obtained. Furthermore, according to this embodiment, by temporarily removing the reaction products and residual gas from the processing chamber during etching and resetting the reaction, it is possible to suppress the occurrence of excessive etching reactions and improve the controllability of the etching amount.

[0150] Furthermore, for example, in step C of the above-described embodiment, the first raw material may be supplied to the processing chamber intermittently, i.e., in a pulsed manner. For example, the supply of the first raw material to the processing chamber and the purging and / or vacuuming of the processing chamber may be performed alternately a predetermined number of times (p times, where p is 1 or an integer of 2 or more). In this case as well, the same effects as in the above-described embodiment can be obtained.

[0151] Furthermore, in step C of the above-described embodiment, a dopant agent may be supplied to the substrate as a first film-forming agent in addition to the first raw material. The dopant agent can be supplied from the dopant agent supply system described above. As the dopant agent, a substance containing any of the Group 15 elements such as phosphorus (P) and arsenic (As), and any of the Group 13 elements such as boron (B), can be used. Examples of dopant agents include phosphine (PH3), arsine (AsH3), diborane (B2H6), and trichloroborane (BCl3). One or more of these can be used as the dopant agent. In this embodiment, the same effects as in the above-described embodiment can be obtained. Furthermore, according to this embodiment, it is possible to form a dopant-doped film (P, As, B, etc.) on the substrate.

[0152] Furthermore, for example, in step C of the above embodiment, a semiconductor element-containing material other than Si may be used as the first raw material, and a semiconductor element-containing film other than a Si-containing film may be formed on the substrate. For example, a Ge-containing material such as monogermane (GeH4) may be used as the first raw material, and a Ge-containing film such as a Ge film may be formed on the substrate. Also, for example, a Si-containing material and a Ge-containing material may be used as the first raw material, and a Si and Ge-containing film such as a SiGe film may be formed on the substrate. Also, for example, in addition to the semiconductor element-containing material as the first raw material, a nitride agent or an oxidizing agent may be used to form a semiconductor element and N-containing film such as a SiN film, SiCN film, SiON film, SiCN film, SiBCN film, SiBN film, or a semiconductor element and O-containing film such as an SiO film or SiOC film on the substrate. Also, for example, a metal element-containing material may be used as the first raw material, and a metal element-containing film such as a W film, Mo film, or Ru film may be formed on the substrate. Furthermore, for example, in addition to the metal element-containing substance as the first raw material, a nitride or oxidizing agent may be used to form metal element and N-containing films such as TiN films, WN films, and AlN films, or metal element and O-containing films such as TiO films, HfO films, ZrO films, and AlO films. In these cases as well, the same effects as those described above can be obtained.

[0153] Furthermore, in step C of the above-described embodiment, for example, an epitaxial film, an amorphous film, a polycrystalline film, or a mixed crystal film thereof may be formed on the substrate. For example, an epitaxial Si film, an amorphous Si film, a poly Si film, or a mixed crystal Si film of amorphous and poly may be formed on the substrate. In these cases as well, the same effects as in the above-described embodiment can be obtained.

[0154] Furthermore, as shown in Figures 7(a) to 7(f), (a) Step A is to prepare a substrate having a first substrate and a second substrate on its surface, wherein an oxide film is formed on the surface of the first substrate and an N-containing film is formed on the surface of the second substrate, (b) Step B may be performed, in which an F-containing substance is supplied to the substrate, and a substance X generated by a chemical reaction between the N-containing film and the F-containing substance is used to etch the oxide film on the surface of the substrate.

[0155] Furthermore, in this case, in step A, as shown in Figures 8(a) to 8(d), (a1) Step A1 involves supplying a modifier to the substrate to adsorb inhibitors contained in the modifier onto the surface of the oxide film, (a2) Step A2 involves supplying a second film-forming agent to a substrate on which an inhibitor has been adsorbed on the surface of an oxide film, thereby forming an N-containing film on the surface of the second substrate. You may choose to do so.

[0156] Each embodiment shown in Figures 7(a) to 7(f) and Figures 8(a) to 8(d) is a modified version of each embodiment shown in Figures 4(a) to 4(f) and Figures 5(a) to 5(d), respectively. Specifically, in Figures 7(a) to 7(f) and Figures 8(a) to 8(d), the "underlayment" in Figures 4(a) to 4(f) and Figures 5(a) to 5(d) is changed to the "first underlayment," the "first N-containing material" to the "second underlayment," and the "second N-containing film" to the "N-containing film." Here, the "second underlayment" is composed of N-free materials (non-nitrides), such as semiconductor element-containing films like Si films, Ge films, SiGe films, SiOC films, and SiC films, or metal element-containing films like W films, Mo films, Ru films, HfO films, ZrO films, and AlO films. The other configurations are similar to those shown in Figures 4(a) to 4(f) and Figures 5(a) to 5(d).

[0157] In the embodiments shown in Figures 7(a) to 7(f) and Figures 8(a) to 8(d), the same effects as those described above can be obtained. That is, in step A, instead of preparing a substrate in which an oxide film is formed on the surface of the substrate and a second N-containing film is formed on the surface of the first N-containing film, the same effects as those described above can be obtained even if a substrate in which an oxide film is formed on the surface of the first substrate and an N-containing film is formed on the surface of the second substrate is prepared.

[0158] Furthermore, for example, in step C of the above-described embodiment, a predetermined film may be selectively formed on some of the surfaces of the multiple types of surfaces exposed by performing step B. For example, in Figure 4(f), the film may be selectively formed on the surface of the substrate or selectively formed on the surface of the first N-containing film. Also, for example, in Figure 7(f), the film may be selectively formed on the surface of the first substrate or selectively formed on the surface of the second substrate. In these cases as well, the same effects as in the above-described embodiment can be obtained.

[0159] It is preferable that the recipes used for each process be prepared individually according to the processing content, recorded and stored in the storage device 121c via a telecommunications line or external storage device 123. When starting each process, it is preferable that the CPU 121a appropriately selects the appropriate recipe from among the multiple recipes recorded and stored in the storage device 121c according to the processing content. This allows the processing device to perform various processes with high reproducibility. Furthermore, it reduces the burden on the operator, avoids operational errors, and allows each process to be started quickly.

[0160] The above-mentioned recipes are not limited to newly created ones; they may also be prepared, for example, by modifying existing recipes already installed on the processing unit. When modifying a recipe, the modified recipe may be installed on the processing unit via a telecommunications line or a recording medium on which the recipe is stored. Alternatively, existing recipes already installed on the processing unit may be directly modified by operating the input / output device 122 provided on the existing processing unit.

[0161] The above-described embodiments illustrate an example of processing using a batch-type processing apparatus that processes multiple substrates at once. This disclosure is not limited to the above-described embodiments and can also be applied to processing using a single-wafer processing apparatus that processes one or several substrates at once. Furthermore, the above-described embodiments illustrate an example of processing using a processing apparatus having a hot-wall type processing furnace. This disclosure is not limited to the above-described embodiments and can also be applied to processing using a processing apparatus having a cold-wall type processing furnace.

[0162] Furthermore, the above-described embodiments have explained an example in which the above-described processing sequence is performed in the same processing chamber of the same processing apparatus (in situ). The disclosure is not limited to the above-described embodiments, and for example, any step of the above-described processing sequence may be performed in different processing chambers of different processing apparatuses (ex situ), or in different processing chambers of the same processing apparatus.

[0163] For example, as shown in Figure 9, this disclosure can also be applied when a processing system including multiple standalone processing units (first to third processing units) is used, and each step is performed ex-situ in different processing chambers of different processing units. For example, step A can be performed in the first processing unit, step B in the second processing unit, and step C in the third processing unit. Alternatively, for example, step A can be performed in the first processing unit, and steps B and C can be performed in the second processing unit. Alternatively, for example, steps A and B can be performed in the first processing unit, and step C can be performed in the second processing unit. In these cases, the first to third processing units are also referred to as the first to third processing units, respectively. The processing system is also referred to as the processing unit.

[0164] Furthermore, this disclosure can also be applied to cases where each step is performed in different processing rooms of the same processing unit, using a processing system that includes a cluster-type processing unit in which multiple processing rooms (first to third processing rooms) are arranged around a transport room, as shown in Figure 10. For example, step A can be performed in the first processing room, step B in the second processing room, and step C in the third processing room. Alternatively, for example, step A can be performed in the first processing room, and steps B and C can be performed in the second processing room. Alternatively, for example, steps A and B can be performed in the first processing room, and step C can be performed in the second processing room. In these cases, the first to third processing rooms are also referred to as the first to third processing units, respectively. Note that the above embodiments and modifications can also be considered examples where the first to third processing units are the same processing unit. The processing system is also referred to as the processing unit.

[0165] Even when using these processing devices (processing systems), each process can be performed using the same processing procedures and conditions as described above, and the same effects as described above can be obtained. Furthermore, when steps B and C of the processing sequence described above are performed ex-situ, it is possible to prevent the introduction of the film-forming agent into the processing chamber where etching is performed, and to prevent the introduction of F-containing substances into the processing chamber where film deposition is performed. As a result, cross-contamination in each processing chamber can be prevented, and the quality of the etching process and the film deposition process can be improved.

[0166] The above-described embodiments and modifications can be used in combination as appropriate. The processing procedure and processing conditions in this case can be the same as, for example, the processing procedure and processing conditions of the above-described embodiments and modifications. [Explanation of Symbols]

[0167] 200 wafers (substrates)

Claims

1. (a) The surface has the required thickness T. １ Thickness T ２ A step of preparing a substrate having a nitrogen-containing film formed to a certain thickness and an oxide film, (b) A step of etching the oxide film on the surface of the substrate by supplying a fluorine-containing substance to the substrate and using a substance X generated by a chemical reaction between the nitrogen-containing film and the fluorine-containing substance, A processing method having the following characteristics.

2. The treatment method according to claim 1, wherein the nitrogen-containing membrane contains silicon and the fluorine-containing substance contains hydrogen.

3. The treatment method according to claim 1, wherein the nitrogen-containing film comprises a silicon nitride film, and the fluorine-containing substance comprises hydrogen fluoride.

4. The processing method according to claim 3, wherein the substance X comprises nitrogen and hydrogen.

5. The substance X is the nitrogen-containing film with a thickness T ２ The processing method according to claim 1, wherein the portion is produced in the process of etching with the fluorine-containing substance.

6. The substance X is the nitrogen-containing film with a thickness T ２ The processing method according to claim 1, wherein the reaction product generated during the etching process of the portion with the fluorine-containing substance decomposes.

7. The processing method according to claim 1, wherein the oxide film includes a silicon oxide film.

8. The treatment method according to claim 1, wherein the oxide film comprises at least one of a native oxide film and a chemical oxide film.

9. (c) The processing method according to claim 1, further comprising the step of supplying a first film-forming agent to the substrate to form a film on the surface of the substrate from which the oxide film has been etched.

10. (a) is, (a1) A step of supplying a modifier to the substrate so that the inhibitor contained in the modifier is adsorbed onto the surface of the oxide film, (a2) By supplying a second film-forming agent to the substrate on which the inhibitor has been adsorbed on the surface of the oxide film, a thickness T is formed on the surface of the substrate. １ The first nitrogen-containing film and thickness T ２ A step of forming a nitrogen-containing film that includes a second nitrogen-containing film and a laminated film, A processing method according to any one of claims 1 to 9, comprising:

11. (a2) The processing method according to claim 10, wherein the second nitrogen-containing film is formed on the first nitrogen-containing film that was previously formed on the surface of the substrate.

12. (a2) The processing method according to claim 10, wherein the laminated film is formed on the surface of the substrate.

13. The treatment method according to claim 10, wherein the inhibitor adsorbed on the surface of the oxide film in (a1) remains, and (b) is performed.

14. (a) The processing method according to claim 10, wherein the nitrogen-containing film is prepared such that the etching resistance of the first nitrogen-containing film to the fluorine-containing substance is higher than the etching resistance of the second nitrogen-containing film to the fluorine-containing substance.

15. (a) The processing method according to claim 10, wherein the nitrogen-containing film is prepared such that the etching resistance of the fluorine-containing substance in at least the portion of the first nitrogen-containing film that is in contact with the second nitrogen-containing film is higher than the etching resistance of the second nitrogen-containing film by the fluorine-containing substance.

16. (a) In, The processing temperature for forming the first nitrogen-containing film is set higher than the processing temperature for forming the second nitrogen-containing film, and After forming the first nitrogen-containing film, and before forming the second nitrogen-containing film, the first nitrogen-containing film is subjected to heat treatment or plasma treatment. The processing method according to claim 10, which involves performing at least one of the following.

17. Of the nitrogen-containing films, thickness T １ The etching resistance of the portion due to the fluorine-containing material is, thickness T ２ A treatment method according to any one of claims 1 to 9, wherein the etching resistance of the portion is higher than that of the fluorine-containing substance.

18. Among the nitrogen-containing films, the thickness T １ Of at least the thickness T of the portion ２ The etching resistance of the fluorine-containing substance in the portion in contact with the portion of is higher than the etching resistance of the fluorine-containing substance in the portion of the thickness T ２ The processing method according to any one of claims 1 to 9, wherein the etching resistance of the fluorine-containing substance in the portion of the thickness T is higher than the etching resistance of the fluorine-containing substance in the portion of the thickness T

19. (b) The processing method according to any one of claims 1 to 9, wherein the supply conditions of the fluorine-containing substance are changed in multiple stages.

20. (b) In the nitrogen-containing film, the thickness T ２ Remove the portion with thickness T １ The processing method according to claim 5 or 6, which leaves a portion of the original.

21. (a) The surface has the required thickness T. １ Thickness T ２ A step of preparing a substrate having a nitrogen-containing film formed to a certain thickness and an oxide film, (b) A step of etching the oxide film on the surface of the substrate by supplying a fluorine-containing substance to the substrate and using a substance X generated by a chemical reaction between the nitrogen-containing film and the fluorine-containing substance, A method for manufacturing a semiconductor device having [a certain feature].

22. A device for preparing circuit boards, A fluorine-containing material supply system that supplies a fluorine-containing material to a substrate, (a) The surface has the required thickness T. １ Thickness T ２ (b) a process of preparing a substrate having a nitrogen-containing film formed to a certain thickness and an oxide film, and (b) a process of etching the oxide film on the surface of the substrate using a substance X generated by a chemical reaction between the nitrogen-containing film and the fluorine-containing substance by supplying a fluorine-containing substance to the substrate, the apparatus and the fluorine-containing substance supply system are configured to control the apparatus and the fluorine-containing substance supply system to perform these processes. A processing device.

23. (a) The surface has the required thickness T. １ Thickness T ２ A procedure for preparing a substrate having a nitrogen-containing film formed to a certain thickness and an oxide film, (b) A procedure for etching the oxide film on the surface of the substrate by supplying a fluorine-containing substance to the substrate and using a substance X generated by a chemical reaction between the nitrogen-containing film and the fluorine-containing substance, A program that causes a computer to execute a command on a processing unit.

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