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

Abstract

The present invention provides a substrate processing method for precisely removing substances from a substrate, a semiconductor device manufacturing method, a program, and a substrate processing apparatus. [Solution] In the processing furnace 202 of the processing apparatus, the method for removing material on the substrate includes the steps of supplying a first gas, which is either an etching gas containing a halogen element or a reaction gas that reacts with the etching gas, to the substrate 200 from a first supply unit 249a, and while performing the above supply, supplying a second gas, which is the other of the etching gas and reaction gas, to the substrate from a second supply unit 249b different from the first supply unit, in such a manner that the distribution of the partial pressure of the reaction product produced by the reaction between the first gas and the second gas within the plane of the substrate is adjusted.

Description

Technical Field

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

Background Art

[0002] As one step in the manufacturing process of a semiconductor device, a process for removing substances on 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 precisely removing substances from a substrate.

Means for Solving the Problems

[0005] According to one aspect of the present disclosure, (a) A step of supplying, to a substrate, a first gas which is either an etching gas containing a halogen element or a reaction gas that reacts with the etching gas, from a first supply unit; (b) While executing (a), a step of supplying, to the substrate, a second gas which is the other of the etching gas and the reaction gas, different from the one, from a second supply unit different from the first supply unit, so as to adjust a distribution in the plane of the substrate of a partial pressure of a reaction product generated by a reaction between the first gas and the second gas; By performing the above, a technology for removing substances on the substrate is provided.

Effects of the Invention

[0006] According to this disclosure, it becomes possible to precisely remove materials from a substrate. [Brief explanation of the drawing]

[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 schematic diagram showing the gas flow to a substrate in one embodiment of the present disclosure. Figures 4(b) to 4(d) are schematic diagrams showing the gas flow to a substrate in a modified example 4 of one embodiment of the present disclosure, respectively. [Figure 5] Figure 5 is a schematic diagram showing the gas flow to the substrate in Modification 5 of one embodiment of the present disclosure. [Figure 6] Figures 6(a) to 6(e) are schematic diagrams showing the flow of the first and second gases to the substrate in a modified example 6 of one aspect of the present disclosure, respectively. [Figure 7] Figures 7(a) to 7(f) are schematic diagrams showing the flow of the first and second gases to the substrate in a modified example 6 of one aspect of the present disclosure, respectively. [Modes for carrying out the invention]

[0008] <One aspect of this disclosure> Hereinafter, one aspect of this disclosure will be described, mainly with reference to Figures 1 to 3 and Figure 4(a). Note that the drawings used in the following description are all schematic, and the dimensional relationships and ratios of the elements shown in the drawings do not necessarily correspond to reality. Furthermore, the dimensional relationships and ratios 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] A reaction tube 203 is arranged concentrically with the heater 207 inside 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 upper end of the manifold 209 is engaged with the lower end of the reaction tube 203 and is configured to support the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a sealing member. The processing 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 part of the processing vessel. The processing chamber 201 is configured to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed in this processing chamber 201.

[0011] Within the processing chamber 201, nozzles 249a and 249b, serving as the first and second supply units, are provided so as to penetrate the side walls of the manifold 209. Nozzles 249a and 249b are also referred to as the first and second nozzles, respectively. Nozzles 249a and 249b are made of a heat-resistant material such as quartz or SiC. Gas supply pipes 232a and 232b are connected to nozzles 249a and 249b, respectively. Nozzles 249a and 249b are different nozzles and are provided adjacent to each other.

[0012] Gas supply pipes 232a and 232b are equipped with, in order from the upstream side of the gas flow, mass flow controllers (MFCs) 241a and 241b, which are flow control devices (flow control units), and valves 243a and 243b, which are on-off valves. Gas supply pipe 232c is connected downstream of valve 243a on gas supply pipe 232a. Gas supply pipe 232d is connected downstream of valve 243b on gas supply pipe 232b. Gas supply pipes 232c and 232d are equipped with, in order from the upstream side of the gas flow, MFCs 241c and 241d, and valves 243c and 243d, respectively.

[0013] As shown in FIG. 2, the nozzles 249a and 249b are respectively provided in the space between the inner wall of the reaction tube 203 and the wafer 200, rising upward along the upper part from the lower part of the inner wall of the reaction tube 203 in the direction of the arrangement of the wafer 200. That is, the nozzles 249a and 249b are respectively provided along the wafer arrangement area on the side of the wafer arrangement area where the wafer 200 is arranged, in a region horizontally surrounding the wafer arrangement area. In a plan view, the nozzle 249a is arranged to face the exhaust port 231a, which will be described later, across the center of the wafer 200 carried into the processing chamber 201. The nozzle 249b is provided adjacent to the nozzle 249a, that is, at a position substantially facing the exhaust port 231a across the wafer 200 accommodated in the processing chamber 201. Gas supply holes 250a and 250b for supplying gas from the outer peripheral direction of the wafer 200 into the plane of the wafer 200 are respectively provided on the side surfaces of the nozzles 249a and 249b. A plurality of gas supply holes 250a and 250b are provided from the lower part to the upper part of the reaction tube 203.

[0014] At least one of the gas supply holes 250a and 250b is configured (adjusted) to supply gas from the outer edge of the wafer 200 into the plane of the wafer 200.

[0015] Here, the gas supply hole 250a is configured to supply gas in a direction from the outer edge of the wafer 200 toward the central portion of the wafer 200, that is, to supply gas along a straight line L1 passing through the gas supply hole 250a and the center of the wafer 200.

[0016] Further, the gas supply hole 250b is configured to supply gas in a direction different from the direction from the outer edge of the wafer 200 toward the central portion of the wafer 200, that is, along a line different from the straight line L2 passing through the gas supply hole 250b and the center of the wafer 200 (a line non-parallel to the straight line L2). Here, the gas supply hole 250b is configured to supply gas to the outside of the central portion of the wafer 200 and toward the inside of the outer edge of the wafer 200.

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

[0018] From the gas supply pipe 232b, the second gas is supplied into the processing chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b.

[0019] Note that as the first gas, either one of an etching gas containing a halogen element and a reaction gas that reacts with this etching gas can be used. Also, as the second gas, a gas that is the other different from the above-mentioned one (the gas used as the first gas) among these gases can be used. That is, when using an etching gas as the first gas, a reaction gas can be used as the second gas, and when using a reaction gas as the first gas, an etching gas can be used as the second gas.

[0020] From the gas supply pipes 232c and 232d, an inert gas is supplied into the processing chamber 201 via the MFCs 241c and 241d, the valves 243c and 243d, the gas supply pipes 232a and 232b, and the nozzles 249a and 249b. The inert gas acts as a purge gas, a carrier gas, a dilution gas, etc.

[0021] Primarily, the first gas supply system is constituted by the gas supply pipe 232a, the MFC 241a, and the valve 243a. Primarily, the second gas supply system is constituted by the gas supply pipe 232b, the MFC 241b, and the valve 243b. Primarily, the inert gas supply system is constituted by the gas supply pipes 232c and 232d, the MFCs 241c and 241d, and the valves 243c and 243d.

[0022] Of the various supply systems described above, one or all of them may be configured as an integrated supply system 248, which is comprised of valves 243a to 243d and MFCs 241a to 241d, etc. The integrated supply system 248 is connected to each of the gas supply pipes 232a to 232d, and the supply operation of various substances (various gases) into the gas supply pipes 232a to 232d, i.e., the opening and closing operation of valves 243a to 243d and the flow rate adjustment operation by MFCs 241a to 241d, etc., is controlled by a controller 121, which will be described later. The integrated supply system 248 is configured as an integrated or segmented integrated unit, and can be attached to and detached from the gas supply pipes 232a to 232d, etc., in units of the integrated unit, and is configured so that maintenance, replacement, and expansion of the integrated supply system 248 can be performed in units of the integrated unit.

[0023] 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 and 249b (gas supply holes 250a and 250b) with the wafer 200 in between, in a plan view. The exhaust port 231a may 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.

[0024] Below the manifold 209, a seal cap 219 is provided, which serves as a furnace opening cover capable of airtightly closing the lower end opening of the manifold 209. An O-ring 220b is provided on the upper surface of the seal cap 219, which serves as a sealing member that contacts the lower end of the manifold 209. Below the seal cap 219, a rotating mechanism 267 is installed for rotating the boat 217, which will be described later. The rotating shaft 255 of the rotating mechanism 267 passes through the seal cap 219 and is connected to the boat 217. The rotating mechanism 267 is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be raised and lowered vertically by a boat elevator 115, which 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 in and out of the processing chamber 201 by raising and lowering the seal cap 219.

[0025] 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. 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 is controlled by a shutter opening and closing mechanism 115s.

[0026] The boat 217, which serves as a substrate support, is configured to support multiple wafers 200, for example 25 to 200 wafers 200, in a horizontal position and aligned vertically with their centers aligned, in multiple layers, that is, arranged with spacing between them. The boat 217 is made of a heat-resistant material such as quartz or SiC. Below the boat 217, multiple layers of heat-insulating plates 218, also made of a heat-resistant material such as quartz or SiC, are supported.

[0027] 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.

[0028] 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 board processing device 100 may be configured to have one control unit, or it may be configured to have multiple control units. That is, the control for performing the processing sequence described later may be performed using one control unit, or it may be performed 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.

[0029] The storage device 121c is composed of, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. The storage device 121c contains, in a readable format, control programs that control the operation of the substrate processing device 100, and process recipes that describe the procedures and conditions for substrate processing, as 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 substrate processing device 100 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.

[0030] I / O port 121d is connected to the MFCs 241a to 241d, valves 243a to 243d, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotary mechanism 267, boat elevator 115, shutter opening / closing mechanism 115s, etc.

[0031] 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 241d, the opening and closing operation of valves 243a to 243d, the opening and closing operation of the APC valve 244 and the pressure adjustment operation of the APC valve 244 based on the pressure sensor 245, the starting and stopping of the vacuum pump 246, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the rotation and rotation speed adjustment operation of the boat 217 by the rotating mechanism 267, 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.

[0032] 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.

[0033] (2) Processing steps Using the above-described processing apparatus, an example of a processing sequence for removing material from a wafer 200, which serves as a substrate, will be explained as one step in the manufacturing process (manufacturing method) of a semiconductor device. 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 a substrate processing apparatus, etching processing apparatus, or etching apparatus. The processing method will also be referred to as a substrate processing method, etching processing method, or etching method.

[0034] In the processing sequence of this embodiment, (a) Step A, in which a first gas, which is either an etching gas containing a halogen element or a reaction gas that reacts with the etching gas, is supplied to the wafer 200 from a nozzle 249a as a first supply unit, (b) Step B, while performing step A, a second gas, which is the other of the etching gas and the reaction gas, is supplied to the wafer 200 from a nozzle 249b, which is a second supply unit different from the first supply unit, in order to adjust the distribution of the partial pressure of the reaction product produced by the reaction between the first gas and the second gas in the plane of the wafer 200 (hereinafter also referred to as the in-plane distribution of partial pressure on the substrate). To do so.

[0035] Furthermore, in the processing sequence of this embodiment, Step B describes a case in which the distribution of the partial pressure of the reaction product within the plane of the wafer 200 is adjusted by adjusting at least one of the supply flow rate of the second gas and the supply direction of the second gas.

[0036] Here, as an example, we will describe the case in step B where at least the supply direction of the second gas is adjusted. Specifically, in step B, we will describe the case where the first gas is supplied in a direction toward the center of the wafer 200, and the second gas is supplied in a direction different from the direction toward the center of the wafer 200.

[0037] In this embodiment, unless otherwise specified, the processing sequence will be explained using the case where the first gas is the reaction gas and the second gas is the etching gas as an example. However, it is also possible to use the reaction gas as the first gas and the etching gas as the second gas.

[0038] In this specification, the term "wafer" may refer to the wafer itself or to a laminate of a wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of the wafer" may refer to the surface of the wafer itself or to the surface of a predetermined layer formed on the wafer. In this specification, when it is stated that "a predetermined layer is formed on the surface of the wafer," it may mean that the predetermined layer is formed directly on the surface of the wafer itself or that the predetermined layer is formed on a layer or other layer already formed on the wafer. In this specification, the term "substrate" has the same meaning as when it is used with the term "wafer."

[0039] (Wafer charge and boat load) Once multiple wafers 200 are loaded into the boat 217, the shutter 219s is moved by the shutter opening / closing mechanism 115s, opening the lower end opening of the manifold 209. Then, as shown in Figure 1, the boat 217 supporting the multiple wafers 200 is lifted by the boat elevator 115 and transported into the processing chamber 201. In this way, the wafers 200 are prepared in the processing chamber 201.

[0040] Furthermore, the surface of the wafer 200 loaded into boat 217 has a substance formed on it that will be etched in the etching process described later. This substance includes oxygen (O)-free materials. Examples of such materials include epitaxial silicon (Si) films, amorphous Si films, polySi films, silicon nitride (SiN) films, and metal-containing films. Examples of metal-containing films include films containing metallic elements such as titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), niobium (Nb), aluminum (Al), molybdenum (Mo), tungsten (W), silicon (Si), and germanium (Ge), as well as individual films of these metallic elements.

[0041] (Pressure adjustment and temperature adjustment) After the boat loading is complete, the processing chamber 201 is evacuated (reduced pressure exhausted) by the vacuum pump 246 to achieve the desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by the 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 the 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 the temperature sensor 263 to ensure a desired temperature distribution inside the processing chamber 201. 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.

[0042] (Etching process) After that, perform step B in parallel while executing step A.

[0043] (Step A) In this step, a first gas is supplied to the wafer 200 in the processing chamber 201. As an example, here we will describe a case where a reaction gas that reacts with the etching gas (described later as the second gas) is supplied as the first gas.

[0044] Specifically, valve 243a is opened, and the first gas flows into the gas supply pipe 232a. The flow rate of the first gas is adjusted by MFC 241a, supplied into the processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, the first gas is supplied (discharged) from the outer edge of the wafer 200 toward the plane of the wafer 200 (first gas supply). More specifically, the first gas is supplied (discharged) in a direction from the outer edge of the wafer 200 toward the center of the wafer 200 (for example, along the straight line L1) (see Figure 4(a)). At this time, valves 243b and 243c may be opened to supply inert gas into the processing chamber 201 via nozzles 249a and 249b, respectively.

[0045] (Step B) In this step, a second gas is supplied to the wafer 200 in the processing chamber 201. Here, as an example, we will describe the case where an etching gas containing halogen elements is supplied as the second gas.

[0046] Specifically, valve 243b is opened, and the second gas flows into the gas supply pipe 232b. The flow rate of the second gas 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 second gas is supplied (discharged) from the outer edge of the wafer 200 toward the plane of the wafer 200 (second gas supply). More specifically, it is supplied (discharged) in a direction different from the direction toward the center of the wafer 200 from the outer edge of the wafer 200 (for example, a direction different from the direction along the straight line L2), for example, in a direction toward the outer edge of the wafer 200 relative to the direction toward the center of the wafer 200 (i.e., a direction away from the supply direction of the first gas) (see Figure 4(a)).

[0047] The reaction gas is a gas that reacts with the etching gas. A gas that reacts with the etching gas is a gas that contains elements that react with the halogen elements contained in the etching gas. Examples of halogen elements include chlorine (Cl), fluorine (F), bromine (Br), and iodine (I). As the first gas, for example, a gas containing hydrogen (H), deuterium (D), or oxygen (O) can be used. As the reaction gas, for example, elemental gases of H, D, or O (i.e., gases composed only of elemental elements) such as H2 gas, D2 gas, O2 gas, or ozone (O3) gas can be used. Alternatively, compound gases composed of H and other elements other than H, such as ammonia (NH3) gas, phosphine (PH3) gas, and monoborane (BH3) gas, can be used as the reaction gas. Furthermore, compound gases composed of oxygen and other elements other than oxygen, such as nitric oxide (NO) gas, carbon monoxide (CO) gas, and carbon dioxide (CO2) gas, can be used as the reaction gas. Of these, it is preferable to use elemental gases of H, D, or O as the reaction gas. Furthermore, it is preferable to use a gas that does not contain halogen elements (halogen-free gas) as the reaction gas. Furthermore, it is particularly preferable to use a reducing gas such as a gas containing H or D as the reaction gas. One or more of these can be used as the reaction gas.

[0048] Etching gases are gases containing halogen elements. Examples of etching gases include elemental halogen gases (i.e., gases composed solely of halogen elements) such as Cl2 gas, F2 gas, Br2 gas, and I2 gas. Alternatively, compound gases composed solely of halogen elements, such as chlorine monofluoride (ClF) gas, chlorine trifluoride (ClF3) gas, and iodine heptafluoride (IF7) gas, can be used. Furthermore, nitrogen-free compound gases composed of halogen elements and other elements, such as boron trichloride (BCl3) gas, can be used. Finally, nitrogen-containing compound gases composed of halogen elements and other elements, such as nitrosyl fluoride (FNO) gas, can be used. One or more of these can be used as etching gases.

[0049] Examples of inert gases that can be used include nitrogen (N2), argon (Ar), helium (He), neon (Ne), and xenon (Xe). One or more of these can be used as the inert gas.

[0050] In steps A and B, the processing conditions when supplying the first and second gases are: Processing temperature: 400-700°C, preferably 450-550°C Processing pressure: 1 to 1330 Pa, preferably 10 to 100 Pa Processing time: 1 to 6000 seconds, preferably 60 to 1800 seconds First gas (reaction gas) supply flow rate: 0.1 to 20 slm, preferably 0.5 to 10 slm Second gas (etching gas) supply flow rate: 0.01 to 2 slm, preferably 0.05 to 1 slm Inert gas supply flow rate (per gas supply pipe): 0-10 slm, preferably 1-5 slm Examples include the following. In this step, it is preferable to supply the first gas and the second gas under non-plasma conditions (atmosphere).

[0051] In this specification, numerical ranges such as "400~700°C" mean that the lower and upper limits are included within that range. For example, "400~700°C" means "400°C or more and 700°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.

[0052] Under the processing conditions described above, by supplying the second gas in such a way that it mixes the first gas and the second gas within the plane of the wafer 200, reaction products can be generated in situ within the plane of the wafer 200 by the reaction between the first gas and the second gas. For example, if H2 gas, which is a reaction gas, is used as the first gas and Cl2 gas, which is an etching gas, is used as the second gas, hydrogen chloride (HCl) gas can be generated as the reaction product. Alternatively, for example, if NO gas, which is a reaction gas, is used as the first gas and F2 gas, which is an etching gas, is used as the second gas, FNO gas can be generated as the reaction product.

[0053] As described above, the reaction products are generated in situ on the surface of the wafer 200, and are supplied to the surface of the wafer 200 in a highly active state, and before their activity is lost, compared to similar substances that have been generated outside the processing chamber 201, i.e., similar substances that have been generated for some time. Thus, in step B, not only the etching gas but also the reaction products in an active state are supplied to the wafer 200.

[0054] Thus, by supplying both the etching gas as a second gas and the reaction product to the wafer 200, the etching gas reacts with the material on the wafer 200, and further reacts with the reaction product with the material on the wafer 200, thereby removing the material from the wafer 200. In other words, the material on the wafer 200 is removed not only by the reaction between the material and the etching gas, but also by the reaction between the material and the reaction product.

[0055] Furthermore, the type and activity of the reaction products vary depending on the combination of etching gas and reaction gas. Therefore, even when the etching gas and reaction products react with a substance under the same conditions (e.g., partial pressure and temperature), the relative magnitudes of the removal rate of the substance by reaction with the etching gas (also called the etching rate) and the removal rate of the substance by reaction with the reaction products may be reversed (changed) depending on the combination of reaction gas and etching gas. For example, when H2 gas is used as the reaction gas and Cl2 gas is used as the etching gas, the removal rate of the substance by reaction between the substance and the etching gas (Cl2 gas) will be greater than the removal rate of the substance by reaction between the substance and the reaction product (HCl gas). Also, for example, when NO gas is used as the reaction gas and F2 gas is used as the etching gas, the removal rate of the substance by reaction between the substance and the etching gas (F2 gas) will be less than the removal rate of the substance by reaction between the substance and the reaction product (FNO gas).

[0056] Furthermore, in this embodiment, the reaction gas selected as the first gas is one in which the rate of removal of the substance by reaction with the reaction gas is smaller than the rate of removal by etching gas, which is the second gas. Preferably, the reaction gas selected as the first gas is one in which the rate of removal of the substance by reaction with the reaction gas is smaller than the rate of removal by reaction products. Even more preferably, the reaction gas selected as the first gas is one in which substantially no etching reaction occurs between the substance and the reaction gas.

[0057] The following shows specific means (adjustment examples) for optimizing the amount of material removed from wafer 200, which is the sum of the amount of material removed by reaction with the second gas (etching gas) (this can also be read as the removal rate, the same applies below) and the amount of material removed by reaction with the reaction product. The various adjustment examples shown below can be used individually or in any combination. In addition, in the various adjustment examples shown below, unless otherwise specified, the explanation will be given using the case where the etching gas is used as the first gas and the reaction gas is used as the second gas. However, it is also possible to use the reaction gas as the first gas and the etching gas as the second gas.

[0058] (Adjustment Example 1) If the in-plane distribution of the etching gas partial pressure is a non-uniform distribution that is maximized in a predetermined region A on the surface of the wafer 200 and gradually decreases as it moves away from this region (hereinafter also referred to as the distribution that is maximized in region A), the in-plane distribution of the reaction product partial pressure is adjusted to be a non-uniform distribution different from that of the etching gas partial pressure distribution.

[0059] For example, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the in-plane distribution of the partial pressure of the reaction products can be made to be a non-uniform distribution in which the partial pressure is minimized in region A in the plane of the wafer 200 and gradually increases as it moves away from this region (hereinafter, such a distribution will also be referred to as the distribution that is minimized in region A). Alternatively, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the in-plane distribution of the partial pressure of the reaction products can be made to be a non-uniform distribution in which the partial pressure is maximized in region B, which is different from region A in the plane of the wafer 200, and gradually decreases as it moves away from this region (hereinafter, such a distribution will also be referred to as the distribution that is maximized in region B). At this time, at least one of the supply direction and supply flow rate of the first gas may be further adjusted so that the in-plane distribution of the partial pressure of the reaction products has the non-uniform distribution described above.

[0060] Here, for example, region A is the outer peripheral region of wafer 200 (i.e., the region close to the nozzle 249b that supplies the second gas), and region B is the central region of wafer 200 (i.e., the region close to the nozzle 249b that supplies the second gas).

[0061] When using a reaction gas as the first gas and an etching gas as the second gas, the supply direction of at least one of the first and second gases can be adjusted so that the partial pressure of the first gas is greater in the central region (region B) than in the outer region (region A), and the partial pressure of the second gas is greater in the outer region (region A) than in the central region (region B). Furthermore, the supply flow rate of at least one of the first and second gases can be adjusted as needed. By supplying the first and second gases in this manner, when the partial pressure distribution of the etching gas is maximum in region A, the partial pressure distribution of the reaction products can be made minimum in region A, and the partial pressure distribution of the reaction products can be made maximum in region B.

[0062] On the other hand, when etching gas is used as the first gas and reaction gas as the second gas, the supply direction of at least one of the first and second gases can be adjusted so that the partial pressure of the first gas is greater in the outer peripheral region (region A) than in the central region (region B), and the partial pressure of the second gas is greater in the central region (region B) than in the outer peripheral region (region A). Furthermore, the supply flow rate of at least one of the first and second gases can be adjusted as needed. By supplying the first and second gases in this manner, it is possible to achieve a distribution where the partial pressure distribution of the etching gas is maximum in region A, the partial pressure distribution of the reaction product is minimum in region A, and the partial pressure distribution of the reaction product is maximum in region B. However, as mentioned above, when the supply direction of the second gas is adjusted toward the outer edge relative to the direction toward the center of the wafer 200, it is easier to achieve the distribution of partial pressures of the first gas, second gas, and reaction product as described above by using etching gas as the second gas.

[0063] (Adjustment Example 2) If the distribution of the partial pressure of the etching gas within the substrate plane is minimal in a predetermined region A within the substrate plane, the distribution of the partial pressure of the reaction product within the substrate plane is adjusted to be a non-uniform distribution different from this distribution.

[0064] For example, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the distribution of the partial pressure of the reaction product within the substrate plane is made to be maximum in region A within the plane of wafer 200. Alternatively, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the distribution of the partial pressure of the reaction product within the substrate plane is made to be minimum in region B, which is different from region A within the plane of wafer 200. In this case, similar to adjustment example 2, at least one of the supply direction and supply flow rate of the first gas may be further adjusted so that the distribution of the partial pressure of the reaction product within the substrate plane becomes the non-uniform distribution described above.

[0065] In this adjustment example, when etching gas is used as the first gas and reaction gas as the second gas, the supply direction of at least one of the first and second gases can be adjusted so that the partial pressure of the first gas is lower in the outer region (region A) than in the central region (region B), and the partial pressure of the second gas is higher in the outer region (region A) than in the central region (region B). Furthermore, the supply flow rate of at least one of the first and second gases can be adjusted as needed. By supplying the first and second gases in this manner, when the partial pressure distribution of the etching gas is minimal in region A, the distribution can be made such that the partial pressure of the reaction product is maximum in region A, and the partial pressure of the reaction product is minimum in region B.

[0066] On the other hand, when a reaction gas is used as the first gas and an etching gas as the second gas, the supply direction of at least one of the first and second gases can be adjusted so that the partial pressure of the first gas is greater in the outer peripheral region (region A) than in the central region (region B), and the partial pressure of the second gas is smaller in the outer peripheral region (region A) than in the central region (region B). Furthermore, the supply flow rate of at least one of the first and second gases can be adjusted as needed. By supplying the first and second gases in this manner, when the partial pressure distribution of the etching gas is minimal in region A, the distribution can be made such that the partial pressure of the reaction product is maximum in region A, and the partial pressure of the reaction product is minimum in region B. However, as mentioned above, when the supply direction of the second gas is adjusted toward the outer edge relative to the direction toward the center of the wafer 200, it is easier to achieve the distribution of partial pressures of the first gas, second gas, and reaction product as described above by using an etching gas as the first gas.

[0067] (Adjustment Example 3) If the in-plane distribution of the reaction product partial pressure is maximum in region A, the in-plane distribution of the etching gas partial pressure is adjusted to be a non-uniform distribution different from this distribution.

[0068] For example, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the distribution of the partial pressure of the etching gas within the substrate plane is made to be minimal in region A. Alternatively, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the distribution of the partial pressure of the etching gas within the substrate plane is made to be maximum in region B, which is different from region A. At this time, at least one of the supply direction and supply flow rate of the first gas may be further adjusted so that the distribution of the partial pressure of the etching gas within the substrate plane becomes the non-uniform distribution described above.

[0069] (Adjustment Example 4) If the in-plane distribution of the reaction product partial pressure is minimal in region A, the in-plane distribution of the etching gas partial pressure is adjusted to be a non-uniform distribution different from this distribution.

[0070] For example, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the distribution of the partial pressure of the etching gas within the substrate plane is made to be maximum in region A. Alternatively, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the distribution of the partial pressure of the etching gas within the substrate plane is made to be minimum in region B, which is different from region A. At this time, at least one of the supply direction and supply flow rate of the first gas may be further adjusted so that the distribution of the partial pressure of the etching gas within the substrate plane becomes the non-uniform distribution described above.

[0071] (Adjustment Example 5) When the distribution of the partial pressure of the etching gas within the substrate plane is a uniform distribution of approximately constant size across the entire surface of the wafer 200, for example, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the distribution of the partial pressure of the reaction product within the substrate plane can be made to have a similar uniform distribution.

[0072] (Adjustment example 6) In each of the multiple regions on the surface of the wafer 200, the amount of material removed by the reaction between the material and the reaction product is varied according to the amount of material removed by the reaction between the material and the etching gas.

[0073] For example, in areas of the wafer 200 where the amount of material removed by reaction with the etching gas is large, the supply direction of the second gas is adjusted as described above, and the supply flow rate of the second gas is adjusted as necessary to reduce the partial pressure of the reaction products in that area and reduce the amount of material removed by reaction with the reaction products. Conversely, in areas where the amount of material removed by reaction with the etching gas is small, the supply direction of the second gas is adjusted as described above, and the supply flow rate of the second gas is adjusted as necessary to increase the partial pressure of the reaction products in that area and increase the amount of material removed by reaction with the reaction products.

[0074] (Adjustment Example 7) To adjust the distribution of the partial pressure of the reaction products within the plane of the wafer 200 (hereinafter also referred to as the in-plane distribution of the partial pressure of the reaction products), at least one of the supply direction of the second gas and the supply flow rate of the second gas is adjusted.

[0075] For example, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, the in-plane distribution of the partial pressure of the reaction products can be adjusted to a desired distribution. At this time, at least one of the supply direction and supply flow rate of the first gas may be further adjusted to adjust the in-plane distribution of the partial pressure of the reaction products.

[0076] (Adjustment example 8) To adjust the distribution of the ratio between the partial pressure of the etching gas and the partial pressure of the reaction product within the plane of the wafer 200 (hereinafter also referred to as the in-plane distribution of the ratio), at least one of the supply direction of the second gas and the supply flow rate of the second gas is adjusted.

[0077] For example, by adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as needed, the in-plane distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction products can be adjusted to a desired distribution. At this time, at least one of the supply direction and supply flow rate of the first gas may be further adjusted to adjust the in-plane distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction products. In this adjustment example, in addition to adjusting the in-plane distribution of the partial pressure of the reaction products as in adjustment example 7, the in-plane distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction products can be adjusted with even greater precision by adjusting the distribution of the partial pressure of the etching gas in the plane of the wafer 200.

[0078] (Adjustment Example 9) To ensure uniform removal of material across the wafer 200, at least one of the following is adjusted: the distribution of the partial pressure of the reaction products across the wafer 200, and the distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction products across the wafer 200.

[0079] By adjusting the supply direction of the second gas as described above, and further adjusting the supply flow rate of the second gas as necessary, at least one of the following—the distribution of the partial pressure of the reaction product within the substrate plane, and the distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction product within the substrate plane—is made to a distribution that results in a uniform amount of material removal within the plane of the wafer 200.

[0080] (After-purge and return to atmospheric pressure) After removing material from the wafer 200, inert gas is supplied as a purge gas into the processing chamber 201 from nozzles 249a and 249b, respectively, and exhausted from exhaust port 231a. This purges the processing chamber 201, removing any remaining gases and reaction by-products. Subsequently, the atmosphere inside the processing chamber 201 is replaced with inert gas, and the pressure inside the processing chamber 201 is returned to atmospheric pressure.

[0081] (Boat unloading and wafer discharge) Subsequently, the seal cap 219 is lowered by the boat elevator 115. Then, the processed wafer 200, supported by the boat 217, is transported out of the reaction tube 203. After being transported out of the reaction tube 203, the processed wafer 200 is removed from the boat 217.

[0082] (3) Effects of this embodiment According to this embodiment, one or more of the following effects can be obtained.

[0083] (a) The distribution of the partial pressure of the active reaction product produced by the reaction between the first gas and the second gas, i.e., the reaction between the reaction gas and the etching gas, is adjusted within the substrate plane. Furthermore, in order to make this adjustment, the distribution of the partial pressure of the etching gas within the substrate plane is also adjusted. By doing so, the distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction product within the substrate plane is adjusted, and the amount of material removed from the wafer 200, which is the sum of the amount of material removed by the reaction with the etching gas (as described above, this can also be read as the removal rate) and the amount of material removed by the reaction with the reaction product, is optimized at various points within the plane of the wafer 200, making it possible to precisely remove material from the wafer 200.

[0084] (b) The second gas is supplied so as to mix the first gas and the second gas in the plane of the wafer 200. This makes it possible to generate the reaction product in situ in the plane of the wafer 200 and to efficiently and effectively adjust the distribution of its partial pressure in the substrate plane. As a result, it becomes possible to remove material from the wafer 200 with greater precision.

[0085] Furthermore, by generating the reaction product on the surface of the wafer 200, particularly in the region where etching reactions occur between the reaction product and the material, the reaction product, in its active state immediately after generation, can be delivered to that region on the surface of the wafer 200, thereby increasing the efficiency of material removal from the wafer 200.

[0086] (c) At least one of the first gas and the second gas is supplied from the outer edge of the wafer 200 toward the plane of the wafer 200. This allows for efficient and effective adjustment of the distribution of reaction product partial pressures across the entire plane of the wafer 200, and enables more precise removal of material from the wafer 200. Furthermore, even when multiple wafers 200 are supported in multiple stages, the first gas and the second gas can be supplied to each wafer 200 in the same manner.

[0087] (d) If the distribution of the partial pressure of the reaction products within the substrate plane is non-uniform, the distribution of the partial pressure of the etching gas within the substrate plane is made to be non-uniform, different from the distribution of the partial pressure of the reaction products, in order to compensate for this. This makes it possible to remove material from the wafer 200 precisely.

[0088] (e) If the distribution of the partial pressure of the etching gas in the substrate plane is non-uniform, the distribution of the partial pressure of the reaction product in the substrate plane is made to be non-uniform, different from the distribution of the partial pressure of the etching gas in the substrate plane, in order to compensate for this. This makes it possible to remove material from the wafer 200 precisely.

[0089] (f) The material on the wafer 200 is removed by the reaction between the material and the etching gas, and also by the reaction between the material and the reaction products. In this case, the amount of material removed from the wafer 200, which is the sum of the amount of material removed by the reaction with the etching gas and the amount of material removed by the reaction with the reaction products, can be optimized at various points on the surface of the wafer 200, making it possible to precisely remove the material from the wafer 200.

[0090] (g) In each of the multiple regions on the surface of the wafer 200, the amount of material removed by reaction with reaction products is varied according to the amount of material removed by reaction with etching gas. For example, in regions on the surface of the wafer 200 where the amount of material removed by reaction with etching gas is large, the amount of material removed by reaction with reaction products is reduced, and in regions where the amount of material removed by reaction with etching gas is small, the amount of material removed by reaction with reaction products is increased. This makes it possible to precisely remove material from the wafer 200 by making the sum of these amounts of material removed from the wafer 200 uniform at various points on the surface of the wafer 200.

[0091] (h) A second gas is supplied to the wafer 200 to adjust the in-plane distribution of the partial pressure of the reaction products. This makes it possible to control the amount of material removed from the wafer 200 more effectively than when only the in-plane distribution of the etching gas partial pressure of the wafer 200 is adjusted.

[0092] (i) A second gas is supplied to the wafer 200 to adjust the distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction product within the substrate plane. This makes it possible to remove material from the wafer 200 more precisely across the entire surface of the wafer 200.

[0093] Furthermore, at least one of the following is adjusted: the distribution of the partial pressure of the reaction products within the substrate plane, and the distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction products within the substrate plane. This makes it possible to effectively control the amount of material removed from the wafer 200 at various points within the wafer 200's surface, for example, making it possible to uniformly remove the amount of material from the wafer 200 across the entire surface of the wafer 200.

[0094] (j) When the reaction gas is supplied as the first gas and the etching gas is supplied as the second gas, the above effects can be effectively obtained.

[0095] (k) Adjust at least one of the following: the supply flow rate of the second gas, or the supply direction of the second gas. This allows for efficient adjustment of the in-plane distribution of the reaction product partial pressure on the substrate, enabling more precise removal of material from the wafer 200.

[0096] Specifically, in step B, the first gas is supplied in a direction toward the center of the wafer 200, and the second gas is supplied in a direction different from that toward the center of the wafer 200. This adjusts the distribution of the partial pressure of the reaction products within the substrate plane, optimizing the amount of material removed from the wafer 200 at various points within the wafer 200's plane, and enabling precise removal of material from the wafer 200.

[0097] In other words, in step B, the first and second gases are supplied such that the partial pressure of the first gas in the central part of the wafer 200 is greater than the partial pressure of the first gas in the outer part of the wafer 200. This efficiently adjusts the distribution of the partial pressure of the reaction product within the substrate plane, making it possible to remove material from the wafer 200 more precisely.

[0098] In other words, in step B, the first and second gases are supplied such that the partial pressure of the second gas at the outer periphery of the wafer 200 is greater than the partial pressure of the second gas at the center of the wafer 200. This efficiently adjusts the distribution of the reaction product's partial pressure across the substrate, making it possible to remove material from the wafer 200 with greater precision.

[0099] (l) In step B, the material on the wafer 200 can be removed not only by the reaction between the material and the etching gas, but also by the reaction between the material and the reaction product. This makes it possible to speed up the removal rate of material from the wafer 200.

[0100] Furthermore, when using a reaction gas composed solely of element H or element D, or a compound gas composed of element H and other elements, the reducing action of the reaction gas can remove impurities generated on the surface of the wafer 200. This creates an environment conducive to etching by the etching gas and reaction products when the etching gas is supplied to the wafer 200, thereby accelerating the removal rate of material from the wafer 200.

[0101] (m) The above effects can be effectively obtained when the etching gas and reaction gas are supplied under non-plasma conditions. Furthermore, it becomes possible to avoid plasma damage to the wafer 200.

[0102] (n) The effects described above can also be obtained when a predetermined substance is arbitrarily selected from the various etching gases, reaction gases, and inert gases described above.

[0103] (4) Variations This disclosure can be modified as follows. The following modifications can be freely combined.

[0104] (Variation 1) In the above-described embodiment, the supply direction of the second gas is adjusted as described above, and the supply flow rate of the second gas is adjusted as necessary. However, it is also possible to adjust only the supply flow rate of the second gas without adjusting the supply direction of the second gas.

[0105] In this modified example, the same effects as in the above-described embodiment can be obtained. Specifically, the in-plane distribution of the partial pressure of the reaction product is adjusted, and furthermore, in order to make this adjustment, the in-plane distribution of the partial pressure of the etching gas is also adjusted. This makes it possible to adjust the in-plane distribution of the ratio between the partial pressure of the etching gas and the partial pressure of the reaction product, and as a result, it becomes possible to precisely remove material from the wafer 200.

[0106] (Modification 2) The above-described embodiments mainly explain the case where the supply direction and supply flow rate of the second gas are adjusted, but the supply direction and supply flow rate of the first gas may be adjusted while adjusting the supply direction and supply flow rate of the second gas. Alternatively, the supply direction and supply flow rate of the first gas may be adjusted without adjusting the supply direction and supply flow rate of the second gas.

[0107] In this modified example, the same effects as in the above-described embodiment can be obtained. Specifically, the in-plane distribution of the partial pressure of the reaction product is adjusted, and furthermore, in order to make this adjustment, the in-plane distribution of the partial pressure of the etching gas is also adjusted. This makes it possible to adjust the in-plane distribution of the ratio between the partial pressure of the etching gas and the partial pressure of the reaction product, and as a result, it becomes possible to precisely remove material from the wafer 200.

[0108] (Variation 3) As shown in Figure 4(b), in step B, the second gas may be supplied in a direction parallel to the supply direction of the first gas in a plan view. Alternatively, as shown in Figure 4(c), in step B, the second gas may be supplied in a direction toward the outer periphery of the wafer 200 in a plan view (for example, along the tangent to the outer edge of the wafer 200 passing through the nozzle 249b). As shown in Figure 4(d), in step B, the second gas may be supplied in a direction outward from the outer edge of the wafer 200 in a plan view.

[0109] In this modified example, the same effects as in the above-described embodiment can be obtained. That is, it becomes possible to adjust the in-plane distribution of the partial pressure of the reaction product and precisely remove the substance from the wafer 200.

[0110] (Modification 4) As shown in Figure 5, nozzles 249a and 249b may be positioned substantially opposite each other, with the central part of the wafer 200 in between. Nozzles 249a and 249b may be arranged such that the narrow angle between the line passing through nozzle 249a and the center of the wafer 200 and the line passing through nozzle 249b and the center of the wafer 200 is, for example, 120 to 170°, preferably approximately 180°.

[0111] In this case, in step B, it is preferable to supply the first gas in a direction toward the center of the wafer 200, and to supply the second gas in a direction toward the center of the wafer 200.

[0112] In this case, it is preferable in step B to adjust the flow rate of at least one of the first gas and the second gas so that the partial pressure of the reaction product in the central part of the wafer 200 is greater than the partial pressure of the reaction product in the outer part of the wafer 200.

[0113] In this case, in step B, in order to adjust the position where the partial pressure of the reaction product is maximum, an inert gas may be added as a carrier gas to at least one of the first gas or the second gas, thereby adjusting the balance of the flow rates of the first gas and the second gas.

[0114] At least one of these methods can achieve the same effects as described above. Specifically, it becomes possible to adjust the in-plane distribution of the reaction product partial pressure and precisely remove material from the wafer 200.

[0115] (Variation 5) As shown in Figure 6(a), a third supply nozzle 249c may be provided on the opposite side of nozzle 249b, across the supply direction of the first gas, that is, across the line passing through nozzle 249a and the center of the wafer 200, and in step B, the second gas may be supplied to the wafer 200 from nozzles 249b and 249c, respectively. The flow rates of the second gas supplied from nozzles 249b and 249c may be the same or different.

[0116] In this case, as shown in Figures 6(b) to 6(d), the second gas may be supplied in a direction parallel to the supply direction of the first gas in a plan view, or it may be supplied toward the outer periphery of the wafer 200, or it may be supplied toward the outer edge of the wafer 200.

[0117] In this case, as shown in Figure 6(e), nozzles 249b and 249c may be positioned substantially opposite each other with the central part of the wafer 200 in between. Nozzles 249b and 249c may be arranged such that the narrow angle between the line passing through nozzle 249b and the center of the wafer 200 and the line passing through nozzle 249c and the center of the wafer 200 is, for example, 120 to 170°, preferably approximately 180°.

[0118] In this case, as shown in Figures 6(a) to 6(e), nozzles 249b and 249c may be positioned symmetrically to each other across the supply direction of the first gas. Furthermore, in this case, the configuration is not limited to those shown in Figures 6(a) to 6(e), and nozzles 249b and 249c may be positioned asymmetrically to each other across the supply direction of the first gas.

[0119] In this case, as shown in Figure 7(a), nozzles 249b and 249c may be positioned substantially opposite nozzle 249a, with the central part of the wafer 200 in between. Nozzles 249a and 249b may be arranged such that the narrow angle between the line passing through nozzle 249a and the center of the wafer 200 and the line passing through nozzle 249b and the center of the wafer 200 is, for example, 90 to 170°, preferably 150° or more. The arrangement of nozzles 249a and 249c may be similar.

[0120] In this case, as shown in Figures 7(b) to 7(e), nozzles 249b and 249c may be positioned asymmetrically to each other across the supply direction of the first gas.

[0121] Alternatively, as shown in Figure 7(f), the second gas may be supplied from nozzle 249a and the first gas from nozzles 249b and 249c.

[0122] At least one of these methods can achieve the same effects as described above. Specifically, it becomes possible to adjust the in-plane distribution of the reaction product partial pressure and precisely remove material from the wafer 200.

[0123] <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.

[0124] In the embodiments described above, an example was given in which the orientation of the openings of the gas supply holes 250a and 250b for supplying the first and second gases was pre-adjusted, but this disclosure is not limited thereto. For example, the orientation of the openings of the gas supply holes 250a and 250b may be adjusted when performing steps A and B.

[0125] In the embodiments described above, examples were given in which the material to be etched includes an oxygen-free material, but this disclosure is not limited to this. This material may include, for example, an oxygen-containing material such as a silicon oxide film (SiO film) or a metal oxide film. In this case as well, the same effects as in the embodiments described above can be obtained depending on the type of etching gas and reaction gas used.

[0126] 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 good reproducibility on films of various film types, composition ratios, film quality, and film thickness. Furthermore, it reduces the burden on the operator and allows each process to be started quickly while avoiding operational errors.

[0127] 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.

[0128] The embodiments and modifications described above illustrate examples of etching using a batch-type processing apparatus that processes multiple substrates at once. This disclosure is not limited to the embodiments described above and can also be applied to etching using a single-wafer processing apparatus that processes one or several substrates at once. Furthermore, the embodiments described above illustrate examples of etching using a processing apparatus having a hot-wall type processing furnace. This disclosure is not limited to the embodiments described above and can also be applied to etching using a processing apparatus having a cold-wall type processing furnace.

[0129] Even when using these processing devices, each process can be carried out using the same processing procedures and conditions as described above for the embodiments and modifications, and the same effects as described above for the embodiments and modifications can be obtained.

[0130] 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]

[0131] 200 wafers (substrates) 249a Nozzle (First supply unit) 249b Nozzle (Second supply unit)

Claims

1. (a) A step of supplying a first gas, which is either an etching gas containing a halogen element or a reaction gas that reacts with the etching gas, to the substrate from a first supply unit, (b) While performing (a), a second gas, which is the other of the etching gas and the reaction gas, is supplied to the substrate from a second supply unit different from the first supply unit, in such a way as to adjust the distribution of the partial pressure of the reaction product produced by the reaction between the first gas and the second gas within the plane of the substrate. A substrate processing method that removes the substance on the substrate by performing the following.

2. (b) The substrate processing method according to claim 1, wherein the second gas is supplied so as to mix the first gas and the second gas in the plane of the substrate.

3. (b) The substrate processing method according to claim 1, wherein the distribution of the partial pressure of the etching gas in the plane of the substrate is made non-uniform.

4. (b) The substrate processing method according to any one of claims 1 to 3, wherein the distribution of the partial pressure of the reaction product in the plane of the substrate is made non-uniform.

5. The substrate processing method according to claim 1, wherein the substance is removed by a reaction between the substance and the etching gas, and also by a reaction between the substance and the reaction product.

6. The substrate processing method according to claim 1 or 5, wherein in each of a plurality of regions within the surface of the substrate, the amount of the substance removed by the reaction between the substance and the reaction product is varied according to the amount of the substance removed by the reaction between the substance and the etching gas.

7. (b) The substrate processing method according to claim 1, wherein the second gas is supplied to the substrate in such a way as to adjust the distribution of the partial pressure of the reaction product in the plane of the substrate.

8. (b) The substrate processing method according to claim 7, wherein the distribution of the partial pressure of the reaction product in the plane of the substrate is adjusted by adjusting at least one of the supply flow rate of the second gas and the supply direction of the second gas.

9. (b) The substrate processing method according to claim 1, wherein the second gas is supplied to the substrate in such a way as to adjust the distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction product in the plane of the substrate.

10. (b) The substrate processing method according to claim 9, wherein the distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction product in the plane of the substrate is adjusted by adjusting at least one of the supply flow rate of the second gas and the supply direction of the second gas.

11. (b) The substrate processing method according to claim 1, wherein at least one of the distribution of the partial pressure of the reaction product in the plane of the substrate and the distribution of the ratio of the partial pressure of the etching gas to the partial pressure of the reaction product in the plane of the substrate is adjusted so that the amount of the substance removed in the plane of the substrate is uniform.

12. (b) The substrate processing method according to claim 1, wherein the distribution of the partial pressure of the reaction product in the plane of the substrate is adjusted by adjusting at least one of the supply flow rate of the second gas and the supply direction of the second gas.

13. (b) The substrate processing method according to claim 1, wherein the first gas is supplied in a direction toward the center of the substrate, and the second gas is supplied in a direction different from the direction toward the center.

14. The first supply unit and the second supply unit are provided at positions substantially opposite to each other, with the central part of the substrate in between. (b) The substrate processing method according to claim 1, wherein the first gas is supplied in a direction toward the center of the substrate and the second gas is supplied in a direction toward the center.

15. A third supply unit is further provided, located on the opposite side of the supply direction of the first gas from the second supply unit. (b) The substrate processing method according to claim 1, wherein the second gas is supplied to the substrate from the third supply unit.

16. The substrate processing method according to any one of claims 7 to 15, wherein the first gas is the reaction gas and the second gas is the etching gas.

17. The substrate processing method according to any one of claims 7 to 15, wherein the first gas is the etching gas and the second gas is the reaction gas.

18. (a) A step of supplying a first gas, which is either an etching gas containing a halogen element or a reaction gas that reacts with the etching gas, to the substrate from a first supply unit, (b) While performing (a), a second gas, which is the other of the etching gas and the reaction gas, is supplied to the substrate from a second supply unit different from the first supply unit, in such a way as to adjust the distribution of the partial pressure of the reaction product produced by the reaction between the first gas and the second gas within the plane of the substrate. A method for manufacturing a semiconductor device, which involves removing a substance on a substrate by performing the following.

19. (a) A procedure for supplying a first gas, which is either an etching gas containing a halogen element or a reaction gas that reacts with the etching gas, to a substrate from a first supply unit, (b) While performing (a), a second gas, which is the other of the etching gas and the reaction gas, is supplied to the substrate from a second supply unit different from the first supply unit, in such a manner as to adjust the distribution of the partial pressure of the reaction product produced by the reaction between the first gas and the second gas within the plane of the substrate. A program that causes a substrate processing device to perform a procedure to remove the substance on the substrate by a computer.

20. A first gas supply system comprising a first supply unit that supplies a first gas to a substrate, which is either an etching gas containing a halogen element or a reaction gas that reacts with the etching gas, A second gas supply system comprising a second supply unit that supplies a second gas, which is the other of the etching gas and the reaction gas, to the substrate, A control unit is configured to control the first gas supply system and the second gas supply system so as to perform the following: (a) the process of supplying the first gas to the substrate from the first supply unit; and (b) the process of supplying the second gas to the substrate from the second supply unit while performing (a) in order to adjust the distribution of the partial pressure of the reaction product produced by the reaction between the first gas and the second gas in the plane of the substrate. A substrate processing apparatus equipped with the following:

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