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

Abstract

This technology provides an efficient method for etching the surface of a substrate. [Solution] (a) A step of placing a product substrate and a non-product substrate on which substance M is adsorbed in a processing chamber; (b) A step of supplying an etching agent to the processing chamber on which the product substrate and the non-product substrate are placed, thereby reacting the substance M adsorbed on the non-product substrate with the etching agent to etch the surface of the product 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 of the manufacturing process of a semiconductor device, a process of etching the surface of a substrate may be performed (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

[0008] <One aspect of this disclosure> The following description will focus on one aspect of this disclosure, primarily with reference to Figures 1-4, 5(a), and 5(b). 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 product substrate. Processing of the wafer 200 is carried out 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 each provided in an annular space between the inner wall of the reaction tube 203 and the wafer 200 in a plan view, 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 to 249c are each provided along the wafer arrangement region on the side of the wafer arrangement region where the wafer 200 is arranged, in a region that horizontally surrounds the wafer arrangement region. In a plan view, the nozzle 249b is arranged to face the exhaust port 231a, which will be 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 respect to the straight line L as the axis of symmetry. Gas supply holes 250a to 250c for supplying gas are provided on the side surfaces of the nozzles 249a to 249c, respectively. The gas supply holes 250a to 250c are each open so as to face (opposite) the exhaust port 231a in a plan view, and are capable of supplying 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 through the MFC241a, the valve 243a, and the nozzle 249a. The F-containing substance is used as one of the etching agents.

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

[0016] From the gas supply pipe 232c, the dopant agent is supplied into the processing chamber 201 via the MFC241c, the valve 243c, and the nozzle 249c. The dopant agent is used as one of the film-forming agents.

[0017] From the gas supply pipe 232d, the reducing agent is supplied into the processing chamber 201 via the MFC241d, the valve 243d, the gas supply pipe 232a, and the nozzle 249a.

[0018] From the gas supply pipe 232e, other raw materials are supplied into the processing chamber 201 via the MFC241e, the valve 243e, the gas supply pipe 232b, and the nozzle 249b. The other raw materials are used as one of the film-forming agents.

[0019] From the gas supply pipes 232f to 232h, inert gases are supplied into the processing chamber 201 via the MFC241f to 241h, the valves 243f to 243h, the gas supply pipes 232a to 232c, and the nozzles 249a to 249c, respectively. The inert gases act as purge gases, carrier gases, dilution gases, etc.

[0020] Primarily, the F-containing substance supply system is constituted by the gas supply pipe 232a, the MFC241a, and the valve 243a. Primarily, the raw material supply system is constituted by the gas supply pipe 232b, the MFC241b, and the valve 243b. Primarily, the dopant agent supply system is constituted by the gas supply pipe 232c, the MFC241c, and the valve 243c. Primarily, the reducing agent supply system is constituted by the gas supply pipe 232d, the MFC241d, and the valve 243d. Primarily, the other raw material supply system is constituted by the gas supply pipe 232e, the MFC241e, and the valve 243e. Primarily, the inert gas supply system is constituted by the gas supply pipes 232f to 232h, the MFC241f to 241h, and the valves 243f to 243h. The F-containing substance supply system is also referred to as the etching agent supply system. Each of the raw material supply system, the dopant agent supply system, and the other raw material supply system is also referred to as a film-forming agent supply system, partially or entirely.

[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) that places the product substrate and the non-product substrate with substance M adsorbed on it inside the processing container.

[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 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 also configured to support a predetermined number (one or more) of non-product wafers as non-product substrates and dummy wafers as dummy substrates in multiple layers, similar to the wafers 200 as product substrates. In addition, the boat 217 is also configured to support side dummy wafers and fill dummy wafers. The boat 217 is made of a heat-resistant material such as quartz or SiC. At the bottom of the boat 217, multiple layers of heat-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 a wafer 200 as a product substrate, and a processing sequence for growing a film on the wafer 200 after etching, will be explained mainly with reference to Figure 4. 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, etching apparatus, film deposition processing apparatus, or film deposition apparatus, depending on the processing content. Similarly, the processing method will also be referred to as a substrate processing method, etching processing method, etching method, film deposition processing method, or film deposition method, depending on the processing content.

[0033] In the processing sequence of this embodiment, (a) Step A, in which a wafer 200 as a product substrate and a non-product wafer on which substance M has been adsorbed are placed in the processing chamber 201, (b) Step B involves supplying an etching agent into a processing chamber 201 in which a wafer 200 and a non-product wafer on which substance M has been adsorbed are placed, thereby reacting the substance M adsorbed on the non-product wafer with the etching agent to etch the surface of the wafer 200. To do so.

[0034] In the following example, (c) Step C is performed by supplying a film-forming agent to the wafer 200 whose surface has been etched, thereby forming a film on the wafer 200. This section describes the case where a cycle including steps A, B, and C is performed a predetermined number of times (n times, where n is 1 or an integer greater than or equal to 2).

[0035] Also, in the following example, The following describes the case where step C is performed in processing chamber 201 after the non-product wafer on which substance M has been adsorbed has been removed.

[0036] Also, in the following example, The following describes the case where step B is performed in the processing chamber 201 with the wafer 200 and the non-product wafer with substance M adsorbed on it supported by a boat 217 as a support, and step C is performed in the processing chamber 201 with the wafer 200 supported by the boat 217.

[0037] Furthermore, in the following example, in the cycle described above, (a') After performing step B and before performing step C, step A' is further performed, in which the boat 217 is removed from inside the processing room 201, the non-product wafers with substance M adsorbed on them are removed from the boat 217 outside the processing room 201, and then the boat 217, with the wafer 200 supported, is brought back into the processing room 201.

[0038] In the following example, In step A', a dummy wafer is loaded as a dummy substrate into the area where the non-product wafer with the adsorbed substance M was removed from the boat 217, and the boat 217 supporting the wafer 200 and the dummy wafer is then transported into the processing room 201.

[0039] Furthermore, in the following example, in the cycle described above, (d) After step C is performed, step D is further performed in which the boat 217 is removed from the processing chamber 201 and the wafer 200 is separated from the boat 217 outside the processing chamber 201 to eliminate the adhesion of the wafer 200 to the boat 217 by the film.

[0040] Furthermore, in the following example, in the cycle described above, (e) Step E is further performed outside the processing room 201 to prepare a non-product wafer on which substance M has been adsorbed. This section describes the case where at least one of steps A, B, C, and D in the m-th cycle (where m is an integer greater than or equal to 1) is performed in parallel with step E in the (m+1)th cycle.

[0041] 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.

[0042] 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 etching agents, reducing agents, and film-forming agents (raw materials, dopants, etc.) may contain gaseous substances, liquid substances such as mist-like substances, or both.

[0043] In this specification and drawings, for convenience, the product substrate (product wafer) is also referred to simply as a wafer or wafer 200. Similarly, in this specification and drawings, for convenience, a non-product substrate (non-product wafer with substance M adsorbed on it) is also referred to simply as a non-product substrate (non-product wafer). For example, in Figure 4, for convenience, the product wafer is simply referred to as a wafer, and the non-product wafer with substance M adsorbed on it is simply referred to as a non-product wafer. Also, in Figures 5(a), 5(b), and 6, for convenience, the product wafer is simply referred to as a wafer.

[0044] (Step A) First, multiple wafers 200, which will serve as product substrates, and non-product wafers, which will have substance M adsorbed onto them, are loaded (wafer charged) into the boat 217.

[0045] Oxides may be formed on the surface of wafer 200. These oxides are silicon oxide films (SiO2) with a non-stoichiometric composition. x The film 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 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.

[0046] The substance M to be adsorbed onto the non-product wafer can be an oxygen (O) and hydrogen (H)-containing substance, for example, a substance containing a hydroxyl group (OH group). Examples of substances M include water (H2O), alcohol (R-OH, where R is a hydrocarbon), hydrogen peroxide (H2O2), etc. One or more of these can be used as substance M. Furthermore, in order to suppress volatilization from the non-product wafer, it is preferable to use a substance M that has hydrogen bonds, such as H2O.

[0047] Non-product wafers with adsorbed substance M can be prepared (fabricated) outside the processing chamber 201 by exposing a substrate such as a silicon (Si) wafer, which is a non-product wafer, to substance M, such as the O and H-containing substance mentioned above. For example, non-product wafers with adsorbed substance M can be prepared by opening the lid of a substrate storage container (FOUP) and introducing air into the container when checking the number and condition of non-product wafers stored inside the container, thereby exposing the non-product wafers to the air. In this case, the substance M adsorbed onto the non-product wafer will include moisture (H2O) from the air.

[0048] Boat 217 can be used to arrange non-product wafers with substance M adsorbed onto them, either one or more wafers 200 (i.e., product substrates) at intervals of one or more wafers 200. The number of non-product wafers with substance M adsorbed onto boat 217 can be less than or equal to the number of wafers 200 loaded onto boat 217, or it can be less than the number of wafers 200 loaded onto boat 217. Boat 217 can be used to arrange multiple wafers 200 and multiple non-product wafers with substance M adsorbed onto them.

[0049] 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 and the non-product wafer with adsorbed material M is lifted by the boat elevator 115 and loaded into the processing chamber 201 (boat load). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0050] Upon completion of the boatloading, as shown in Figure 5(a), the processing chamber 201 will contain wafers 200 as product substrates and non-product wafers with substance M adsorbed on them as non-product substrates. Figure 5(a) shows the case where the non-product wafers with substance M adsorbed on them are arranged every other wafer, i.e., every other product substrate. The non-product wafers with substance M adsorbed on them are positioned at a distance from the wafers but adjacent to them.

[0051] (Pressure adjustment and temperature adjustment) After the boat loading is complete, the processing chamber 201, i.e., the space containing the wafer 200 and the non-product wafer with the adsorbed material M, is evacuated (reduced pressure exhausted) by the vacuum pump 246 to a desired pressure (vacuum level). At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback-controlled based on this measured pressure information. The wafer 200 and the non-product wafer in the processing chamber 201 are also heated by the heater 207 to a 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 in the processing chamber 201. The rotation of the wafer 200 and the non-product wafer is also started by the rotation mechanism 267. The exhaust of the processing chamber 201, the heating of the wafer 200 and the non-product wafer, and the rotation are all continued at least until the processing of the wafer 200 is completed.

[0052] (Step B) Subsequently, an etching agent is supplied into the processing chamber 201, where the wafer 200 and the non-product wafer with substance M adsorbed on it are placed.

[0053] Specifically, valve 243a is opened and the etching agent is flowed into the gas supply pipe 232a. The etching agent's flow rate is adjusted by MFC 241a and supplied into the processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, the etching agent is supplied to the wafer 200 and the non-product wafer from the side, and the wafer 200 and the non-product wafer are exposed to the etching agent (etching 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.

[0054] Under the processing conditions described later, by supplying an etching agent into the processing chamber 201 with the wafer 200 and a non-product wafer on which substance M is adsorbed, the substance M adsorbed on the non-product wafer reacts with the etching agent, and the reaction product obtained from this reaction can be used to etch the surface of the wafer 200, that is, the oxide on the surface of the wafer 200.

[0055] For example, if the oxide on the surface of wafer 200 contains silicon oxide (SiO2), the substance M adsorbed on the non-product wafer contains water (H2O), and the etching agent 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. That is, the reaction product obtained by the reaction between substance M (H2O) and the etching agent (HF) is HF2 - By using methods such as those mentioned above, it becomes possible to etch the oxide (SiO2) on the surface of the wafer 200.

[0056] 2HF + H2O → HF2 - +H3O + SiO2 + 2HF2 - +2H3O + → SiF4 + 4H2O

[0057] As described above, according to this disclosure, etching of oxide (SiO2) on the surface of wafer 200 can be initiated by a reaction between an etching agent (HF) and a substance M (H2O) adsorbed on a non-product wafer. When etching of the oxide begins, the substance M adsorbed on the non-product wafer is consumed. However, in this reaction system, since water (H2O) is generated by the etching of the oxide, the above reaction can be repeated in a chain reaction without additional supply of substance M into the processing chamber 201, thereby etching the oxide on the surface of wafer 200. Note that if additional supply of substance M is given into the processing chamber 201 in this reaction system, the amount of substance M in this reaction system will become excessive, which may actually hinder the progress of the etching reaction.

[0058] After etching the surface of the wafer 200, valve 243a is closed to stop the supply of etching agent to the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any remaining gaseous substances. At this time, valves 243f to 243h are opened and inert gas is supplied to 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. It is preferable that the processing temperature during purging in this step is the same as the processing temperature when supplying the etching agent.

[0059] At this time, valve 243d may be opened to supply a reducing agent into the processing chamber 201 instead of, or together with, the inert gas. Alternatively, cycle purging may be performed using the inert gas and / or the reducing agent. When cycle purging is performed, the purging of the processing chamber 201 by supplying at least one of the inert gas and / or the reducing agent to the processing chamber 201 and the exhaust (vacuum exhaust) of the processing chamber 201 may be performed alternately a predetermined number of times, preferably multiple times. Alternatively, with the processing chamber 201 exhausted, the supply of the reducing agent to the processing chamber 201 and the supply of the inert gas to the processing chamber 201 may be performed alternately a predetermined number of times, preferably multiple times. Alternatively, with one of the inert gas and / or the reducing agent continuously supplied to the processing chamber 201, the supply of the other of the inert gas and / or the reducing agent to the processing chamber 201 and the exhaust of the processing chamber 201 may be performed alternately a predetermined number of times, preferably multiple times. These measures enable the efficient and effective removal of residual substances from the treatment chamber 201. When an inert gas is used as the purge gas, the treatment chamber 201 is purged primarily by physical action. On the other hand, when a reducing agent is used as the purge gas, not only physical action but also chemical action can be produced, further enhancing the purging effect. When performing cycle purging, the opening and closing of valves 243f~243h and valve 243d are controlled as appropriate in accordance with the supply timing of the inert gas or reducing agent.

[0060] The processing conditions when supplying the etching agent in step B are as follows: Processing temperature: Room temperature (25°C) to 170°C, preferably 25 to 150°C, more preferably 25 to 130°C Processing pressure: 10-4000, preferably 500-2000 Pa Processing time: 1 to 120 minutes, preferably 10 to 100 minutes Etching agent 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.

[0061] In this specification, numerical ranges such as "25~170°C" mean that the lower and upper limits are included within that range. For example, "25~170°C" means "25°C or more and 170°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.

[0062] Here, if the processing temperature when supplying the etching agent 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.

[0063] 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.

[0064] Furthermore, while setting the processing temperature above 170°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.

[0065] By setting the processing temperature to 170°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 150°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 130°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.

[0066] Based on the above, it is desirable that the processing temperature described above be between room temperature (25°C) and 170°C, preferably between 25°C and 150°C, and more preferably between 25°C and 130°C.

[0067] As mentioned above, fluorine-containing substances can be used as etching agents. For example, fluorine-containing substances containing hydrogen (H), such as hydrogen fluoride (HF), can be used. Also, for example, fluorine (F2), nitrogen trifluoride (NF3), chlorine trifluoride (ClF3), chlorine fluoride (ClF), etc., can be used as etching agents. One or more of these can be used as etching agents.

[0068] 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.

[0069] As reducing agents, for example, hydrogen-containing substances such as hydrogen (H2) and deuterium (D2), or deuterium-containing substances can be used. One or more of these can be used as reducing agents.

[0070] (After-purge and return to atmospheric pressure) After step B 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).

[0071] (Step A') Subsequently, the seal cap 219 is lowered by the boat elevator 115, opening the lower end of the manifold 209. Then, the processed wafers 200 and non-product wafers, supported by the boat 217, are unloaded from the lower end of the manifold 209 to the outside of the reaction tube 203 (boat unloading). After boat unloading, the shutters 219s are moved, and the lower end opening of the manifold 209 is sealed by the shutters 219s via the O-ring 220c (shutter closing).

[0072] After the boat unloading, non-product wafers are removed from boat 217 outside processing room 201 (wafer discharge). Then, dummy wafers are loaded as dummy substrates into the gaps left by the removal of the non-product wafers from boat 217 (wafer charge).

[0073] After the loading of the dummy wafers is complete, the shutter is opened and the boat is loaded using the same procedure as in step A. Upon completion of the boat loading, the processing chamber 201 will contain the wafer 200 as the product substrate and the dummy wafer as the dummy substrate, as shown in Figure 5(b). Figure 5(b) shows the case where the dummy wafers are arranged in intervals of several wafers, i.e., intervals of several product substrates.

[0074] Note that when step A' is performed, the etched wafer 200 may be exposed to the atmosphere. However, even in this case, the surface of wafer 200 is in a state that is resistant to oxidation, and wafer 200 is in an atmosphere (environment) that is resistant to oxidation. That is, the surface of wafer 200 after step B is hydrogen (H) terminated, and the temperature of wafer 200 at the time of boat unloading is below the processing temperature in step B (room temperature to 170°C), which is a relatively low temperature. Therefore, the H termination is less likely to detach from the surface of wafer 200, and dangling bonds are less likely to form on the surface of wafer 200. Even if wafer 200 is exposed to the atmosphere in this state, the surface of wafer 200 will be protected by the H termination, and the state that is resistant to oxidation will be maintained. Even if the surface of wafer 200 is oxidized by performing step A', the degree of oxidation will be very slight. Therefore, as will be described later, before starting step C, if necessary, baking treatment in a reducing agent atmosphere can be performed to remove trace amounts of oxides formed on the surface of the wafer 200 by reacting them with the reducing agent.

[0075] (Pressure adjustment and temperature adjustment) After step A' is completed, the processing chamber 201 is evacuated by the vacuum pump 246 so that the pressure inside reaches the predetermined processing pressure described in step C. Additionally, the output of the heater 207 is adjusted so that the temperatures of the wafer 200 and the dummy wafer reach the predetermined processing temperature described later.

[0076] As described above, before starting step C, a bake treatment may be performed under a reducing agent atmosphere as needed. Specifically, the output of the heater 207 is adjusted so that the temperatures of the wafer 200 and the dummy wafer are the baking treatment temperatures. Then, valve 243d is opened and the reducing agent is flowed into the gas supply pipe 232d. The flow rate of the reducing agent 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 reducing agent is supplied to the wafer 200 and the dummy wafer from the side of the wafer 200, and the wafer 200 and the dummy wafer are exposed to the reducing agent (reducing agent supply, exposure). At this time, valves 243f to 243h may be opened and inert gas may be supplied into the processing chamber 201 via nozzles 249a to 249c, respectively.

[0077] The processing conditions for the baking process are as follows: Processing temperature: 700-1000°C, preferably 800-900°C Processing pressure: 30-2000 Pa, preferably 30-1000 Pa Processing time: 30-120 minutes, preferably 30-90 minutes Reducing agent supply flow rate: 1 to 10 slm, preferably 1 to 5 slm Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm, preferably 1 to 10 slm Examples are given.

[0078] By supplying a reducing agent to the wafer 200 and dummy wafer under the processing conditions described above, it becomes possible to remove substances including by-products such as organic matter and moisture remaining on the surfaces of the wafer 200 and dummy wafer and inside the processing chamber 201 after the completion of step A' by reacting them with the reducing agent. In other words, this step makes the surfaces of the wafer 200 and dummy wafer and the inside of the processing chamber 201 clean, and this clean state can be maintained until step C is performed. Note that if the surfaces of the wafer 200 and dummy wafer and the inside of the processing chamber 201 can be kept clean after step B and before step C is performed, the bake process may be omitted. Figure 4 shows an example in which the bake process is omitted.

[0079] (Step C) Subsequently, raw materials for film formation and a reducing agent are supplied into the processing chamber 201, where the wafer 200 and the dummy wafer are placed.

[0080] Specifically, valves 243b and 243d are opened, and the raw material and reducing agent are supplied into the gas supply pipes 232b and 232d, respectively. The flow rates of the raw material and reducing agent are adjusted by MFCs 241b and 241d, respectively, and supplied into the processing chamber 201 via nozzles 249b and 249a, and exhausted from exhaust port 231a. At this time, the raw material and reducing agent are supplied to the wafer 200 and dummy wafer from the side, and the wafer 200 and dummy wafer are exposed to the raw material and reducing agent (raw material + reducing 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.

[0081] Under the processing conditions described later, by supplying raw materials and a reducing agent into the processing chamber 201 with the wafer 200 and a dummy wafer placed inside, it becomes possible to form a predetermined film on the surface of the wafer 200 from which oxides have been removed. When the surface of the wafer 200 is composed of single-crystal Si, and when the raw materials and reducing agent are the substances described later, it becomes possible to grow and form an epitaxial Si film as a film on the surface of the wafer 200. At this time, the action of the reducing agent keeps the surface of the wafer 200 and the inside of the processing chamber 201 clean, allowing for proper epitaxial growth and the formation of a high-purity epitaxial Si film.

[0082] After forming a predetermined film on the surface of the wafer 200, valves 243b and 243d are closed to stop the supply of raw materials and reducing agents into the processing chamber 201. Then, using the same processing procedure and conditions as in step B, any remaining gaseous substances in the processing chamber 201 are removed (purged). It is preferable that the processing temperature during purging in this step is the same as the processing temperature when supplying the raw materials and reducing agents.

[0083] The processing conditions when supplying raw materials and reducing agents 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 Raw material supply flow rate: 0.1 to 5 slm, preferably 0.2 to 3 slm Reducing agent supply flow rate: 1 to 20 slm, preferably 1 to 10 slm Inert gas supply flow rate (per gas supply pipe): 0-20 slm, preferably 0.1-10 slm Examples are given.

[0084] Examples of raw materials include monosilane (SiH4), disilane (Si2H6), trisilane (Si3H8), and tetrasilane (Si4H 10Silicon hydride such as ) can be used.

[0085] As reducing agents, for example, H-containing substances such as H2 and D2, or D-containing substances can be used. One or more of these can be used as reducing agents.

[0086] (After-purge and return to atmospheric pressure) After step C is completed, the treatment chamber 201 is purged using the same treatment procedure as the after-purging and atmospheric pressure restoration described above, the atmosphere inside the treatment chamber 201 is replaced with an inert gas, and the pressure inside the treatment chamber 201 is restored to atmospheric pressure.

[0087] (Boat unloading) Subsequently, the boat 217 supporting the processed wafer 200 and dummy wafer is unloaded using the same processing procedure as in step A', and the lower end opening of the manifold 209 is sealed by the shutter 219s.

[0088] (Step D) After the boat unloading, a process is performed outside the processing chamber 201 to remove any adhesion between the wafer 200 and the boat 217 caused by the film formed in step C. This process can be carried out, for example, by temporarily removing (picking up) the wafer 200 from the boat 217. For example, this process can be carried out by performing the reverse operation of loading the wafer 200 into the boat 217 during wafer charging. If a dummy wafer adheres to the boat 217 at this time, the same process is performed on the dummy wafer as well. For example, the adhesion of the dummy wafer to the boat 217 can be removed by temporarily removing the dummy wafer from the boat 217 together with the wafer 200.

[0089] Note that when board unloading or step D is performed, the film-deposited wafer 200 may be exposed to the atmosphere. At this time, if the temperature of wafer 200 is relatively high (500-650°C), the H-terminants may detach from the surface of wafer 200, creating dangling bonds on the surface of wafer 200, making the surface of wafer 200 susceptible to oxidation. If wafer 200 is exposed to the atmosphere in this state, oxygen in the atmosphere may combine with the dangling bonds formed on the surface of wafer 200, causing oxidation of the surface of wafer 200. However, the oxide formed at this time can be etched and removed in step B of the next cycle.

[0090] [Perform the prescribed number of times] By performing the cycle including steps A to D described above a predetermined number of times (n times, where n is 1 or an integer of 2 or more), a film of a desired thickness can be formed on the wafer 200. It is preferable to perform this cycle multiple times. That is, as illustrated in Figure 6, it is preferable to make the thickness of the film formed by performing the cycle including steps A to D once (the thickness of the first film and the second film, respectively) thinner than the desired film thickness, and to repeat the above cycle multiple times until the thickness of the film stacked on the wafer reaches a predetermined thickness. Figure 6 shows an example in which this cycle has been performed twice. In Figure 6, the first film is shown as the film formed in the first cycle, and the second film is shown as the film formed in the second cycle. The dashed lines indicate the areas of the surface after oxide has been removed by etching in step B of each cycle. The dashed line between the wafer and the first film indicates the areas of the surface after oxide formed on the surface of the wafer has been removed by etching in step B of the first cycle. Furthermore, the dashed line between the first and second films indicates the area of ​​the surface after the oxide formed on the surface of the first film, which was removed by etching in step B of the second cycle when the wafer was removed from the processing chamber 201 in step D of the first cycle.

[0091] Here, if the cycle including steps A to D is performed multiple times, the used dummy wafer is replaced with a new non-product wafer on which substance M is adsorbed after each cycle. That is, after step D of the mth cycle (where m is an integer greater than or equal to 1), the used dummy wafer is removed from the boat 217 (wafer discharge), and in the wafer charge of step A of the m+1th cycle, a new non-product wafer on which substance M is adsorbed is loaded into the space where the dummy wafer was removed from the boat 217, i.e., the space that became gapped (wafer charge).

[0092] Furthermore, when performing the cycle including steps A to D multiple times, it is preferable to perform step E, which involves preparing a non-product wafer with substance M adsorbed on it, outside the processing chamber 201, in parallel with the execution of this cycle. That is, it is preferable to perform at least one of steps A, B, C, and D in the m-th cycle (where m is an integer of 1 or more) and step E in the m+1th cycle in parallel.

[0093] (Wafer discharge) After a film of the desired thickness is formed on the wafer 200, the processed wafer 200 and the dummy wafer are removed from the boat 217 (wafer discharge).

[0094] The processing step in one aspect of this disclosure is thus completed.

[0095] (3) Effects of this embodiment According to this embodiment, one or more of the following effects can be obtained.

[0096] (a) In step B, when etching the surface of the product substrate, an etching agent and a substance M adsorbed on a non-product substrate are used. This allows the etching agent to react with a small amount of substance M, thereby accelerating the etching reaction. As a result, etching can be performed efficiently. It is also possible to improve the uniformity of the etching.

[0097] Furthermore, the etching process temperature can be increased, and if other processes such as film deposition are performed at least before or after the etching process, the etching process temperature can be brought closer to the processing temperature of the other 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.

[0098] Furthermore, since there is no need to set up a separate supply line to supply substance M into the processing chamber, it is possible to reduce the equipment cost. Also, by eliminating the supply line for supplying substance M, the supply system can be simplified, and the effort and cost of maintenance of the supply system can be reduced. In addition, by adsorbing substance M onto a non-product substrate and supplying it into the processing chamber without setting up a supply line for substance M, it becomes possible to precisely control the minute amount of substance M supplied.

[0099] (b) In step B, the oxide on the surface of the product substrate is etched. This makes it possible to effectively obtain the effects described above. Furthermore, if the oxide contains a silicon oxide film of a non-stoichiometric composition, the effects described above can be effectively obtained. Furthermore, if the oxide contains at least one of the native oxide film and the chemical oxide film, the effects described above can be effectively obtained.

[0100] (c) The etching agent contains a substance containing F, and substance M contains oxygen and hydrogen. This makes it possible to effectively obtain the above-mentioned effects.

[0101] (d) Step B is performed with non-product substrates on which substance M has been adsorbed arranged in the processing chamber, with one or more product substrates in between. This allows substance M to be placed (supplied) between product substrates, that is, to be present around the product substrates, making it possible to effectively obtain the above-mentioned effect. Alternatively, by performing Step B with product substrates and non-product substrates on which substance M has been adsorbed arranged in the processing chamber, and keeping the number of non-product substrates on which substance M has been adsorbed to be less than or equal to the number of product substrates, or even less than the number of product substrates, it is possible to effectively obtain the above-mentioned effect. Furthermore, by performing Step B with multiple product substrates and multiple non-product substrates on which substance M has been adsorbed arranged in the processing chamber, it is possible to effectively obtain the above-mentioned effect.

[0102] (e) In steps A and B, the non-product substrate with substance M adsorbed can be supported in the same way as the product substrate by a support that supports the product substrate. This eliminates the need to provide a separate member in the processing chamber for positioning the non-product substrate with substance M adsorbed. Furthermore, the non-product substrate with substance M adsorbed can be transported to the support using the same transport device as the product substrate. In other words, it eliminates the need to provide a separate transport device for transporting the non-product substrate with substance M adsorbed.

[0103] (f) In step C, a film-forming agent is supplied to the product substrate whose surface has been etched to form a film on the product substrate. This makes it possible to reduce the impurity concentration (oxygen concentration, etc.) at the interface between the product substrate and the film. Furthermore, by performing the cycle including steps A to C a predetermined number of times, for example multiple times, it is possible to reduce the impurity concentration (oxygen concentration, etc.) at the interface between the product substrate and the film, and also to reduce the impurity concentration (oxygen concentration, etc.) at the interface between the film formed in the mth cycle and the film formed in the m+1th cycle.

[0104] (g) Step C is performed in the processing chamber with the non-product substrate on which substance M has been adsorbed removed. That is, after performing step B and before performing step C, step A' is performed in which the support is removed from the processing chamber, the non-product substrate on which substance M has been adsorbed is removed from the support outside the processing chamber, and the support with the product substrate attached is brought into the processing chamber. This makes it possible to form a film without reacting the film-forming agent with substance M adsorbed on the non-product substrate. As a result, it is possible to suppress film formation defects, allow the film to grow properly, and form a film of high purity.

[0105] (h) Step B is performed in the processing chamber with the product substrate and the non-product substrate on which substance M has been adsorbed supported by a support, and Step C is performed in the processing chamber with the product substrate supported by the support. In other words, the product substrate is supported in the same way in Steps A, B and Step C. This eliminates the need to reload the product substrate at each step, thereby increasing productivity.

[0106] (i) In step A', a dummy substrate is loaded into the area where the non-product substrate with substance M adsorbed on it was removed from the support, and the support containing the product substrate and the dummy substrate is brought into the processing chamber. In other words, the area where the non-product substrate with substance M adsorbed on it was removed from the support is not left gap. This makes it possible to make the distance between each product substrate, that is, the size of the space between each product substrate, uniform, and in step C, it becomes possible to make the flow of the film-forming agent to each product substrate uniform. As a result, it becomes possible to improve the uniformity of the film thickness between product substrates.

[0107] (j) After step C is performed, the support is removed from the processing room, and the product substrate is separated from the support outside the processing room. This makes it possible to eliminate the adhesion of the product substrate to the support due to the film.

[0108] (k) In step E, a non-product substrate with substance M adsorbed onto it is prepared outside the processing room. For example, in step E, a non-product substrate with substance M adsorbed onto it is prepared by exposing it to the atmosphere. In this case, substance M will contain moisture (H2O) from the atmosphere. Thus, in step E, there is no need to prepare a product substrate with a special film or mechanism containing moisture formed on the surface or back surface, and it is possible to avoid increased costs.

[0109] (l) Step E is performed outside the processing room to prepare a non-product substrate on which substance M has been adsorbed. At least one of steps A, B, C, and D in the mth cycle (where m is an integer greater than or equal to 1) and step E in the m+1th cycle are performed in parallel. This prevents the cycle time, i.e., the processing time from becoming excessively long, and makes it possible to avoid a decrease in productivity.

[0110] (m) By making the shape and size of non-production substrates the same as those of product substrates, it becomes possible to handle non-production substrates and product substrates in the same way. For example, transferring substrates between the FOUP and the support, loading substrates into the support, supporting substrates with the support, and storing substrates in the FOUP can be done in the same way for both non-production substrates and product substrates. This makes it possible to avoid increased costs and decreased productivity.

[0111] (n) The above-mentioned effects can also be obtained when a predetermined substance is arbitrarily selected from the above-mentioned various etching agents, various film-forming agents, various reducing agents, and various inert gases.

[0112] <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.

[0113] For example, in step A' of the above-described embodiment, after removing the non-product substrate with substance M adsorbed from the support outside the processing chamber, the support supporting only the product substrate may be brought into the processing chamber without loading a dummy substrate into the space where the non-product substrate was removed. In other words, step C may be performed inside the processing chamber with only the product substrate supported by the support, without supporting the dummy substrate with the support. In this case as well, the same effects as in the above-described embodiment can be obtained.

[0114] Furthermore, for example, in the cycle of the above-described embodiment, step D may be omitted, and the cycle including steps A, B, and C may be performed a predetermined number of times (n times, where n 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. When step D is omitted and the cycle including steps A, B, and C is performed multiple times, it is preferable to perform step E, in which a non-product substrate with substance M adsorbed on it is prepared outside the processing room, and to perform at least one of steps A, B, and C in the m-th cycle and step E in the m+1th cycle in parallel. This makes it possible to prevent the cycle time, i.e., the processing time from becoming longer, as in the above-described embodiment, and to avoid a decrease in productivity.

[0115] Furthermore, in step B of the above-described embodiment, the etching agent may be supplied to the processing chamber intermittently, i.e., in a pulsed manner. For example, the supply of the etching agent to the processing chamber and the purging and / or vacuuming of the processing chamber may be performed alternately a predetermined number of times (x times, where x 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. Moreover, according to this embodiment, by temporarily removing the reaction products and residual gases 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.

[0116] Furthermore, in step C of the above-described embodiment, a dopant agent may be supplied to the product substrate as a film-forming agent in addition to the raw materials and reducing agent. 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 product substrate.

[0117] Furthermore, for example, in step C of the above embodiment, a material containing semiconductor elements other than Si may be used to form a semiconductor element-containing film other than a Si-containing film on the product substrate. For example, a material containing germanium (Ge), such as monogermane (GeH4), may be used as a raw material to form a Ge-containing film, such as a Ge film, on the product substrate. Also, for example, a Si-containing material and a Ge-containing material may be used as raw materials to form a Si and Ge-containing film, such as a SiGe film, on the product substrate. Furthermore, for example, an oxidizing agent or a nitriding agent may be used in addition to a Si-containing material to form a Si-based insulating film, such as a silicon oxide film (SiO film), a silicon nitride film (SiN film), or a silicon oxynitride film (SiON film), on the product substrate. Also, for example, a material containing metal elements such as tungsten (W), molybdenum (Mo), aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), or tantalum (Ta) may be used as a raw material to form a metal element-containing film on the product substrate. Furthermore, for example, a metal element-containing material and a Si-containing material may be used as raw materials to form a metal element and Si-containing film, such as a metal silicide film, on the product substrate. Alternatively, for example, an oxidizing agent may be used in addition to a metal element-containing material and a Si-containing material to form a metal element, Si, and oxygen-containing film, such as a metal silicate film, on the product substrate. In these cases as well, the same effects as those described above can be obtained. When using two or more raw materials, such as when using a Si-containing material and a Ge-containing material, or when using a metal element-containing material and a Si-containing material, these materials can be supplied simultaneously or non-simultaneously using a raw material supply system and other raw material supply systems.

[0118] Furthermore, in step C of the above-described embodiment, in addition to the epitaxial film, an amorphous film, a polycrystalline film, or a mixed crystalline film thereof may be formed on the product substrate. For example, in addition to the epitaxial Si film, an amorphous Si film, a poly Si film, or a mixed crystalline Si film of amorphous and poly may be formed on the product substrate. In these cases as well, the same effects as in the above-described embodiment can be obtained.

[0119] 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.

[0120] 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.

[0121] 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.

[0122] 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.

[0123] 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.

[0124] 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. [Examples]

[0125] As an example, a Si wafer with a native oxide film formed on its surface and a Si wafer with moisture adsorbed from the atmosphere on its surface (hereinafter referred to as a moisture-adsorbed wafer) were placed in a processing chamber, and HF gas was supplied to the processing chamber to etch the surface of the Si wafers. At that time, the etching amount was measured when the processing temperature during HF gas supply was set to 50, 75, 100, 150, and 200°C. Other processing conditions during HF gas supply were set to predetermined conditions within the processing condition range of step B of the above embodiment.

[0126] As a comparative example, a Si wafer with a native oxide film formed on its surface was placed in the processing chamber without any moisture-adsorbing wafers. HF gas was supplied to the processing chamber, and the surface of the Si wafer was etched. The etching amount was measured at processing temperatures of 50, 75, and 100°C during HF gas supply. Other processing conditions during HF gas supply were the same as those in the examples.

[0127] Figure 7 shows the measurement results of the amount of etching of the native oxide film on the surface of a Si wafer. In Figure 7, the horizontal axis represents the processing temperature [°C] when HF gas is supplied, and the vertical axis represents the amount of etching of the native oxide film [au]. The solid line in Figure 7 represents the measurement results of the amount of etching of the native oxide film in the example, and the dashed line represents the measurement results of the amount of etching of the native oxide film in the comparative example. The circles and squares in Figure 7 represent the measurement results for wafers placed in the lower and upper parts of the processing chamber, respectively. As shown in Figure 7, the amount of etching of the native oxide film in the example does not decrease at all in the processing temperature range of 130°C or below, the decrease is very small even in the range of 130°C to 150°C, and it can be seen that a sufficiently practical amount of etching can be obtained even in the range of 150°C to 170°C. In contrast, it can be seen that the amount of etching of the native oxide film in the comparative example decreases significantly in the temperature range of 75°C or above. In other words, according to the example, it is possible to efficiently etch the native oxide film on the surface of a Si wafer at a relatively high temperature, and productivity can be greatly increased. [Explanation of Symbols]

[0128] 200 wafers (product substrates) 201 Processing Room

Claims

1. (a) A step of placing a product substrate and a non-product substrate on which substance M has been adsorbed inside the processing chamber, (b) A step of etching the surface of the product substrate by supplying an etching agent into the processing chamber in which the product substrate and the non-product substrate are arranged, thereby reacting the substance M adsorbed on the non-product substrate with the etching agent, A processing method having the following characteristics.

2. (b) The processing method according to claim 1, wherein the oxide on the surface of the product substrate is etched.

3. The treatment method according to claim 2, wherein the oxide comprises a silicon oxide film with a non-stoichiometric composition.

4. The treatment method according to claim 2, wherein the oxide comprises at least one of a native oxide film and a chemical oxide film.

5. The processing method according to claim 1, wherein the etching agent contains a fluorine-containing substance, and the substance M contains an oxygen and hydrogen-containing substance.

6. The processing method according to claim 1, wherein (b) is performed in the processing chamber with the non-product substrates arranged in an alternating pattern of one or more product substrates.

7. The processing method according to claim 1, wherein (b) is performed with the product substrate and the non-product substrate arranged in the processing chamber, and the number of non-product substrates is less than or equal to the number of product substrates, or less than the number of product substrates.

8. The processing method according to claim 1, wherein (b) is performed with a plurality of product substrates and a plurality of non-product substrates arranged in the processing chamber.

9. The processing method according to claim 1, wherein (b) is performed in the processing chamber with the product substrate and the non-product substrate supported by a support.

10. (c) The process further comprises the step of supplying a film-forming agent to the product substrate whose surface has been etched, thereby forming a film on the product substrate. The processing method according to any one of claims 1 to 9, which involves performing a cycle including (a), (b), and (c) a predetermined number of times.

11. The processing method according to claim 10, wherein (c) is performed in the processing chamber with the non-product substrate removed.

12. The processing method according to claim 10, wherein (b) is performed in the processing chamber with the product substrate and the non-product substrate supported by a support, and (c) is performed in the processing chamber with the product substrate supported by the support.

13. The aforementioned cycle is The processing method according to claim 12, further comprising the steps of: after performing (a') and (b), and before performing (c), removing the support from the processing chamber, removing the non-product substrate from the support outside the processing chamber, and then bringing the support, with the product substrate supported, into the processing chamber.

14. The processing method according to claim 13, wherein (a') a dummy circuit board is loaded into the space where the non-product circuit board was removed from the support, and the support supporting the product circuit board and the dummy circuit board is brought into the processing chamber.

15. The aforementioned cycle is The processing method according to claim 12, further comprising the step of removing the support from the processing chamber after performing (d) and (c), and separating the product substrate from the support outside the processing chamber, thereby eliminating the adhesion of the product substrate to the support by the film.

16. (e) The processing method according to any one of claims 1 to 9, further comprising the step of preparing the non-product substrate on which the substance M has been adsorbed outside the processing chamber.

17. The processing method according to claim 16, wherein the substance M includes moisture in the atmosphere.

18. The aforementioned cycle is (e) The process further comprises preparing the non-product substrate on which the substance M has been adsorbed outside the processing chamber, The processing method according to claim 10, wherein at least one of (a), (b), and (c) in the mth cycle (where m is an integer of 1 or more) and (e) in the m+1th cycle are performed in parallel.

19. The aforementioned cycle is (e) The process further comprises preparing the non-product substrate on which the substance M has been adsorbed outside the processing chamber, The processing method according to claim 15, wherein at least one of (a), (b), (c), and (d) in the mth cycle (where m is an integer of 1 or more) and (e) in the m+1th cycle are performed in parallel.

20. (a) A step of placing a product substrate and a non-product substrate on which substance M has been adsorbed inside the processing chamber, (b) A step of etching the surface of the product substrate by supplying an etching agent into the processing chamber in which the product substrate and the non-product substrate are arranged, thereby reacting the substance M adsorbed on the non-product substrate with the etching agent, A method for manufacturing a semiconductor device having [a certain feature].

21. Processing room and An apparatus comprising a processing chamber in which a product substrate and a non-product substrate on which substance M has been adsorbed are placed, An etching agent supply system that supplies an etching agent into the aforementioned processing chamber, A control unit is configured to control the apparatus and the etching agent supply system so as to perform the following processes: (a) a process in which the product substrate and the non-product substrate are placed in the processing chamber; and (b) a process in which the etching agent is supplied to the processing chamber in which the product substrate and the non-product substrate are placed, thereby reacting the substance M adsorbed on the non-product substrate with the etching agent to etch the surface of the product substrate. A processing device.

22. (a) A procedure for arranging a product substrate and a non-product substrate on which substance M has been adsorbed inside the processing chamber, (b) A procedure to etch the surface of the product substrate by supplying an etching agent into the processing chamber in which the product substrate and the non-product substrate are placed, thereby reacting the substance M adsorbed on the non-product substrate with the etching agent, A program that causes a computer to execute a command on a processing unit.

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