Substrate processing device, sacrificial part, substrate processing method, semiconductor device production method, and program

Abstract

This substrate processing device includes a processing container provided with a processing region in which a substrate is processed, an etching agent supply unit for supplying an etching agent to the substrate within the processing region, and a sacrificial part provided in a path through which the etching agent flows within the processing container, the sacrificial part being capable of generating a substance X that reacts with the etching agent to promote an etching process on the substrate.

Description

Substrate processing apparatus, sacrificial parts, substrate processing method, semiconductor device manufacturing method, and program

[0001] This disclosure relates to a substrate processing apparatus, sacrificial parts, a substrate processing method, a semiconductor device manufacturing method, and a program.

[0002] As part of the manufacturing process for semiconductor devices, etching of the substrate surface is sometimes performed (see, for example, Patent Document 1).

[0003] Japanese Patent Publication No. 2023-137735

[0004] This disclosure provides a technology that enables efficient etching of the surface of a substrate.

[0005] According to one aspect of the present disclosure, a technology is provided comprising: a processing container provided with a processing area for processing a substrate; an etching agent supply unit for supplying an etching agent to a substrate in the processing area; and a sacrificial part provided in a path through which the etching agent flows within the processing container, which reacts with the etching agent to generate a substance X that promotes etching of the substrate.

[0006] According to this disclosure, it becomes possible to efficiently etch the surface of a substrate.

[0007] Figure 1 is a schematic diagram of a vertical processing furnace of a processing apparatus preferably used in one embodiment of the present disclosure, showing the processing furnace 202 portion in a vertical cross-sectional view. Figure 2 is a schematic diagram of a vertical processing furnace of a processing apparatus preferably used in one embodiment of the present disclosure, showing the processing furnace 202 portion in a cross-sectional view along line A-A in Figure 1. Figure 3 is a schematic diagram of a controller 121 of a processing apparatus preferably used in one embodiment of the present disclosure, showing the control system of the controller 121 in a block diagram. Figure 4 is a schematic vertical cross-sectional view showing the processing container portion of a processing apparatus preferably used in one embodiment of the present disclosure.

[0008] <An Embodiment of the Disclosure> An embodiment of the disclosure will be described below, mainly with reference to Figures 1 to 4. Note that the drawings used in the following description are 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) As shown in the configuration diagram 1 of the substrate processing apparatus, 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 that activates the gas with heat.

[0010] A reaction tube 203 is arranged inside the heater 207, concentrically with the heater 207. The reaction tube 203 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. 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, and a processing area R for processing the wafer 200 is provided inside it.

[0011] Within the processing chamber 201, nozzles 249a and 249b, which serve as the first and second supply units, are provided so as to penetrate the side walls of the manifold 209, respectively. Gas supply pipes 232a and 232b are connected to nozzles 249a and 249b, respectively.

[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 232d is connected downstream of valve 243a on gas supply pipe 232a. Gas supply pipes 232c and 232e are connected downstream of valve 243b on gas supply pipe 232b. Gas supply pipes 232c to 232e are equipped with, in order from the upstream side of the gas flow, MFCs 241c to 241e and valves 243c to 243e, respectively.

[0013] As shown in Figure 2, nozzles 249a and 249b are provided in the space between the inner wall of the reaction tube 203 and the wafer 200, extending upward from the lower part of the inner wall of the reaction tube 203 towards the direction of wafer 200 arrangement. That is, nozzles 249a and 249b are provided in the area horizontally surrounding the wafer arrangement area, on the side of the wafer arrangement area where the wafers 200 are arranged, and are provided along the wafer arrangement area. Nozzle 249a is positioned opposite the exhaust port 231a, which will be described later, with the center of the wafer 200 being brought into the processing chamber 201 in between. Nozzle 249b is provided adjacent to nozzle 249a, that is, in a position substantially opposite the exhaust port 231a with the wafer 200 housed in the processing chamber 201 in between. Gas supply holes 250a and 250b for supplying (discharging) gas are provided on the sides of nozzles 249a and 249b, respectively. Multiple gas supply holes 250a and 250b are provided, respectively, extending from the lower to the upper part of the reaction tube 203, at positions facing the wafer arrangement region, and are configured to supply gas from the outer peripheral direction of the wafer 200 toward the plane of the wafer 200. In this specification, the wafer arrangement region and the processing region R refer to the same region.

[0014] Etching agent is supplied from the gas supply pipe 232a into the processing chamber 201 via the MFC 241a, valve 243a, and nozzle 249a. In this specification, the nozzle 249a is also referred to as the etching agent supply unit.

[0015] From the gas supply pipe 232b, the raw material is supplied into the processing chamber 201 via the MFC 241b, valve 243b, and nozzle 249b. The raw material is used as one of the film-forming agents.

[0016] From the gas supply pipe 232c, the reducing agent is supplied into the processing chamber 201 via the MFC 241c, valve 243c, and nozzle 249b.

[0017] Inert gas is supplied from gas supply pipes 232d and 232e into the processing chamber 201 via MFCs 241d and 241e, valves 243d and 243e, gas supply pipes 232a and 232b, and nozzles 249a and 249b, respectively. The inert gas acts as a purge gas, carrier gas, diluent gas, etc.

[0018] The etching agent supply system is mainly composed of gas supply pipe 232a, MFC 241a, and valve 243a. The raw material supply system is mainly composed of gas supply pipe 232b, MFC 241b, and valve 243b. The reducing agent supply system is mainly composed of gas supply pipe 232c, MFC 241c, and valve 243c. The inert gas supply system is mainly composed of gas supply pipes 232d, 232e, MFC 241d, 241e, and valves 243d, 243e. The raw material supply system is also called the film-forming agent supply system.

[0019] Any or all of the above-mentioned supply systems may be configured as an integrated supply system 248, which includes valves 243a to 243e and MFCs 241a to 241e, etc.

[0020] An exhaust port 231a for exhausting the atmosphere inside the processing chamber 201 is provided below the side wall of the reaction tube 203. An exhaust pipe 231 is connected to the exhaust port 231a. To the exhaust pipe 231, a vacuum pump 246 as a vacuum exhaust device is connected via a pressure sensor 245 serving as a pressure detector (pressure detection unit) that detects the pressure inside the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 serving as a pressure regulator (pressure adjustment unit). The APC valve 244 can perform vacuum exhaust and stop vacuum exhaust inside the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is in operation, and is further configured to be capable of adjusting the pressure inside the processing chamber 201 by adjusting the valve opening degree based on the pressure information detected by the pressure sensor 245 while the vacuum pump 246 is in operation. The exhaust system is mainly constituted by 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.

[0021] Below the manifold 209, a seal cap 219 is provided as a furnace opening lid body capable of airtightly closing the lower end opening of the manifold 209. On the upper surface of the seal cap 219, an O-ring 220b is provided as a sealing member that abuts against the lower end of the manifold 209. Below the seal cap 219, a rotation mechanism 267 serving as a rotation unit for rotating a boat 217 to be described later is installed. A rotation shaft 255 of the rotation mechanism 267 penetrates through the seal cap 219 and is connected to the boat 217. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be moved up and down in the vertical direction by a boat elevator 115 serving as an elevating mechanism (first elevating unit) installed outside the reaction tube 203. The boat elevator 115 is configured as a transfer device (transfer mechanism) that loads and unloads (transports) the wafers 200 into and out of the processing chamber 201 by moving the seal cap 219 up and down.

[0022] A boat 217 serving as a substrate support is configured to support a plurality of, for example 25 to 200, wafers 200 in multiple stages by aligning them in a vertical direction in a horizontal posture with their centers aligned with each other, that is, to arrange them at intervals. The boat 217 has a top plate 217a and a bottom plate 217b at the top and bottom. A plurality of (for example, three) support posts 213 are installed between the top plate 217a and the bottom plate 217b. Each of the support posts 213 is provided with a plurality of holding portions for holding (supporting) the outer edge of the wafer 200 at predetermined intervals along the arrangement direction of the wafers 200. A plurality of heat insulating plates 218 are supported in multiple stages at the lower part of the boat 217. The boat 217 (the top plate 217a, the bottom plate 217b, the support posts 213, and the heat insulating plates 218) is made of, for example, quartz (SiO ２ ) or a heat-resistant material such as silicon carbide (SiC).

[0023] A temperature sensor 263 serving as a temperature detector is installed in the reaction tube 203. By adjusting the power supply state to the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature inside the processing chamber 201 achieves a desired temperature distribution.

[0024] A sacrificial part 270 is provided outside the processing region R in the reaction tube 203, specifically in the space between the nozzle 249a and the processing region R, at a position closer to the processing region R than the nozzle 249a. The sacrificial part 270 is a member that reacts with the etchant supplied into the processing chamber 201 via the nozzle 249a to generate a substance X that promotes the etching treatment on the wafers 200, and is made of, for example, SiO ２It is made of heat-resistant material such as the above. The sacrificial part 270 is made of a rod shape such as a cylindrical or rectangular parallelepiped, and recesses such as grooves or indentations are provided at predetermined locations on its surface. The vertical size (length) of the sacrificial part 270 is preferably such that at least a part of the sacrificial part 270 does not protrude above the insulation plate 218 located at the top when the sacrificial part 270 is stored in the storage position described later (for example, 5 to 10 cm). The horizontal size (width) of the sacrificial part 270 is preferably smaller than the horizontal size (width) of the support column 213 provided on the boat 217 (for example, 1 to 2 cm). The sacrificial part 270 is made so that it can move vertically inside the reaction tube 203 by a parts elevator 215 described later. The sacrificial part 270 is also made so that it can be removed from the parts elevator 215.

[0025] A shaft 275 supporting the sacrificial part 270 is connected to the lower end of the sacrificial part 270. A parts elevator 215, which serves as a lifting mechanism (second lifting section), is provided at the lower end of the shaft 275. The parts elevator 215 is configured to allow the sacrificial part 270 to move vertically up and down via the shaft 275. In this specification, the position in the movement region of the sacrificial part 270 that corresponds to a position below the processing region R (i.e., the position of the heat insulating plate 218 or a position below it) is referred to as the storage position. The storage position is the position when the sacrificial part 270 is stored when not in operation. Furthermore, the positions in the movement region of the sacrificial part 270 that correspond to predetermined positions in the upper region, middle region, and lower region of the processing region R are referred to as the first position, third position, and second position, respectively (see Figure 4).

[0026] 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 entire control system may perform the control necessary to carry out the processing sequence described later. 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.

[0027] 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 substrate processing, etc. The process recipe is a combination of steps in the substrate processing (film deposition, etc.), described later, which the controller 121 uses to cause the processing device to execute and obtain predetermined results; it functions as a program. 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.

[0028] The I / O port 121d is connected to the MFCs 241a to 241e, valves 243a to 243e, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotating mechanism 267, boat elevator 115, parts elevator 215, etc.

[0029] 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 241e, the opening and closing operation of valves 243a to 243e, 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 raising and lowering operation of the sacrificial parts 270 by the parts elevator 215, in accordance with the contents of the read recipe.

[0030] The controller 121 can be configured by installing the above-mentioned program, which is recorded and stored in the external storage device 123, into 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, when the term recording media is used, it 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.

[0031] (2) Processing Process Using the above-described processing apparatus, an example of a processing sequence in which a substrate is processed as one step in the manufacturing process (manufacturing method) of a semiconductor device, namely, a process of etching the surface of the wafer 200 as the substrate and a process of forming 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.

[0032] In this embodiment, the processing sequence includes: (a) step A, which is to prepare the wafer 200 in the processing area R within the processing container; (b) step B, which is to supply an etching agent to the wafer 200 in the processing area R; and (c) step C, which is to react the etching agent with a sacrificial part 270 provided in the path through which the etching agent flows within the processing container to generate a substance X that promotes the etching process on the wafer 200.

[0033] In the following example, we will describe the case in which, after performing step C, a film-forming agent is supplied to the etched surface 200 to form a film on the wafer 200 in step D.

[0034] 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.

[0035] 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 substance X, the etching agent, and the reducing agent may contain a gaseous substance, a liquid substance such as a mist-like substance, or both.

[0036] (Adjustment of the placement position of the sacrificial parts) The sacrificial parts 270, which are placed in the storage position, are lifted by the parts elevator 215 and placed at a predetermined position (for example, a first position) on the path through which the etching agent flows from the gas supply hole 250a toward the processing area R, where etching is to be promoted.

[0037] (Preparation of substrates [wafer charging and boat loading]: Step A) After multiple wafers 200 are loaded into the boat 217, the boat 217 is lifted by the boat elevator 115 and transported into the processing chamber 201. In this way, the wafers 200 loaded into the boat 217 are placed in the processing area R within the processing chamber 201. At this time, it is preferable that the boat 217 is positioned such that the nozzle 249a, the sacrificial part 270, and the support column 213 are not in a straight line.

[0038] (Pressure and Temperature Adjustment) After boat loading is complete, the processing chamber 201, i.e., the processing space where the wafer 200 is located, is evacuated (reduced pressure exhaust) by a vacuum pump 246 so that it reaches the desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by a pressure sensor 245, and the APC valve 244 is feedback controlled based on this measured pressure information (pressure adjustment). The wafer 200 inside the processing chamber 201 is also heated by a heater 207 so that it reaches 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 so that the processing chamber 201 has the desired temperature distribution (temperature adjustment). 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 carried out continuously at least until the processing of the wafer 200 is completed.

[0039] (Etching process: Steps B and C) Then, steps B and C are performed. Specifically, step B is performed while step C is performed in parallel.

[0040] [Step B] In this step, an etching agent is supplied to the wafer 200 in the processing chamber 201, specifically in the processing area R.

[0041] Specifically, valve 243a is opened and etching agent is flowed into gas supply pipe 232a. The etching agent's flow rate is adjusted by MFC 241a and supplied into processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, etching agent is supplied to the wafer 200 from the side of the wafer 200. At this time, valves 243d and 243e may be opened to supply inert gas into processing chamber 201 via nozzles 249a and 249b, respectively.

[0042] [Step C] In this step, the etching agent and the sacrificial part 270 are reacted to generate a substance X that promotes the etching process on the wafer 200.

[0043] Specifically, in step B, when the etching agent is supplied into the processing chamber 201 via the nozzle 249a, the etching agent is supplied to the sacrificial part 270 from the side of the sacrificial part 270. At this time, the sacrificial part 270 and the etching agent react to produce substance X.

[0044] Oxides may be formed on the surface of wafer 200. These oxides are silicon oxide films (SiO₂) of non-stoichiometric composition. ｘ A film (where x is a real number less than 2) and a silicon oxide film (SiO) of stoichiometric composition. ２ It may contain at least one of the following (films). Furthermore, the oxide may contain at least one of the following: native oxide film and chemical oxide film. ｘ membranes and SiO ２ The membrane will be collectively referred to as the SiO membrane below.

[0045] Under the processing conditions described later, by supplying an etching agent into the processing chamber 201, it becomes possible to etch the surface of the wafer 200 by reacting the etching agent with the generated substance X or a part of its molecular structure.

[0046] For example, if the etching agent supplied into the processing chamber 201 contains hydrogen fluoride (HF) and the sacrificial part 270 is SiO ２When configured with a material containing, under the conditions described later, the reaction represented by the following formula can be allowed to proceed. That is, in steps B and C, the etchant (HF) and the sacrificial part 270 (SiO ２ ) react to generate, for example, a substance X containing water (H ２ O).

[0047] 4HF + SiO ２ →SiF ４ + 2H ２ O

[0048] Then, for example, when the oxide on the surface of the wafer 200 contains silicon oxide (SiO ２ ), under the conditions described later, the reaction represented by the following formula can be initiated and allowed to proceed. That is, in steps B and C, the etching species (HF ２ O) generated by the reaction between the substance X (H ２ － etc.) can etch and remove the oxide (SiO ２ ) present on the surface of the wafer 200.

[0049] 2HF + H ２ O → HF ２ － + H ３ O ＋ SiO ２ + 2HF ２ － + 2H ３ O ＋ →SiF ４ + 4H ２ O

[0050] As described above, according to the present disclosure, the etching of the oxide (SiO ２ ) on the surface of the wafer 200 can be initiated using the reaction between the etchant (HF) supplied into the processing chamber 201 and the trace amount of the substance X (H ２ O) generated by the reaction between the etchant and the sacrificial part 270 as a trigger.

[0051] Examples of processing conditions when supplying the etching agent in steps B and C include: Processing temperature: room temperature (25°C) to 170°C, preferably 25 to 150°C Processing pressure: 10 to 4000, preferably 500 to 2000 Pa Etching agent supply flow rate: 0.5 to 3 slm, preferably 1 to 2 slm Etching agent supply time: 1 to 120 minutes, preferably 5 to 60 minutes Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm, preferably 1 to 5 slm. It is preferable that the etching agent is supplied at a timing when the nozzle 249a, sacrificial part 270, and support column 213 are not in a straight line. Preferably, the etching agent is not supplied when the nozzle 249a, sacrificial part 270, and support column 213 are in a straight line (timing).

[0052] In this specification, numerical ranges such as "25 to 170°C" mean that the lower and upper limits are included within that range. For example, "25 to 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, in other words, the pressure of the space in which the wafer 200 is located. Processing time means the time for which the processing is continued. Also, if the supply flow rate includes 0 slm, 0 slm means the case in which the substance (gas) is not supplied. These also apply in the following explanations.

[0053] Here, if the processing temperature when supplying the etching agent in steps B and C 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.

[0054] 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.

[0055] During the execution of steps B and C, for example, the sacrificial part 270, which is positioned at a first position (a position corresponding to a predetermined position in the upper region of the processing area R), is lowered at a predetermined speed to a second position (a position corresponding to a predetermined position in the lower region of the processing area R). This allows material X to be supplied to the entire processing area R (for example, the upper region, the middle region, and the lower region), and etching can be performed on the wafer 200 located in any of these regions.

[0056] Within the processing region R, differences in temperature, partial pressure, and etching agent supply flow rate may occur between regions, which may result in differences in the etching rate of oxides on the wafer 200 between regions. In this case, for example, when lowering the sacrificial part 270 from the first position to the second position, it is preferable to stop the sacrificial part 270 for a predetermined time at a position corresponding to a region with a low etching rate. Specifically, for example, if the etching rate in the lower region is smaller than that in the upper or middle region, it is preferable to stop the sacrificial part 270 for a predetermined time at the second position corresponding to the lower region. Also, for example, if the etching rate in the middle or lower region is smaller than that in the upper region, it is preferable to stop the sacrificial part 270 for a predetermined time at the third position and the second position corresponding to the middle and lower regions. In this case, it is preferable to make the stopping times of the sacrificial part 270 at the third position and the second position different depending on the etching rates in the middle and lower regions. This allows for the generation of a larger amount of substance X in areas corresponding to low etching rates compared to other areas, thereby improving the uniformity of the oxide etching process across substrates.

[0057] As mentioned above, fluorine-containing substances can be used as etching agents, for example, fluorine-containing substances such as HF and hydrogen (H) can be used. Also, for example, fluorine (H) can be used as an etching agent. ２ ), nitrogen trifluoride (NF ３ ), chlorine trifluoride (ClF ３), chlorine fluoride (ClF), etc. can be used. One or more of these can be used as etching agents.

[0058] For example, substance X is water (H ２ O) and hydrogen peroxide (H ２ O ２ Oxygen (O) and hydrogen (H)-containing substances such as ) can be used.

[0059] As an inert gas, nitrogen (N ２ Other gases such as argon (Ar), helium (He), neon (Ne), and xenon (Xe) 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.

[0060] 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 243d and 243e are opened to supply inert gas to the processing chamber 201 via nozzles 249a and 249b. The inert gas supplied from nozzles 249a and 249b acts as a purge gas, thereby purging the processing chamber 201.

[0061] After the etching process is complete, the parts elevator 215 is activated to move the sacrificial parts 270 to their storage positions.

[0062] (Step D: Substrate Processing) Next, a raw material, which is a film-forming agent, is supplied to the wafer 200 whose surface has been etched. In this step, a reducing agent is supplied to the wafer 200 along with the raw material.

[0063] Specifically, valves 243b and 243c are opened, and the raw material and reducing agent are flowed into the gas supply pipes 232b and 232c, respectively. The flow rates of the raw material and reducing agent are adjusted by MFCs 241b and 241c, respectively, and supplied into the processing chamber 201 via nozzle 249b, and exhausted from exhaust port 231a. At this time, the raw material and reducing agent are supplied to the wafer 200 from the side of the wafer 200, and the wafer 200 is exposed to the raw material and reducing agent (raw material + reducing agent supply, exposure). In contrast, since there is no gas supply hole 250b in the position opposite the storage position of nozzle 249b, the raw material and reducing agent are not supplied to the sacrificial part 270 that has been moved (retracted) to the storage position. At this time, valves 243d and 243e may be opened to supply inert gas into the processing chamber 201 via nozzles 249a and 249b, respectively.

[0064] By supplying raw materials and a reducing agent to the wafer 200 under the processing conditions described later, it becomes possible to form a predetermined film on the surface of the etched wafer 200. For example, if the surface of the wafer 200 exposed by the etching process is composed of single-crystal Si, and the raw materials and reducing agent are substances described later, it becomes possible to grow and form an epitaxial Si film as a film on the surface of the wafer 200.

[0065] Examples of processing conditions when supplying raw materials and reducing agents in step D include: Processing temperature: 500 to 650°C, preferably 550 to 600°C; Processing pressure: 4 to 200 Pa, preferably 1 to 120 Pa; Processing time: 10 to 120 minutes, preferably 20 to 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 to 20 slm, preferably 0.1 to 10 slm.

[0066] As a raw material, for example, monosilane (SiH ４ ), disilane (Si ２ H ６ ), trisilane (Si ３ H ８ ), tetrasilane (Si４ H １０ Silicon hydride such as ) can be used. One or more of these can be used as raw materials.

[0067] Examples of reducing agents include hydrogen (H ２ ), deuterium (D ２ H-containing substances such as ) and deuterium (D)-containing substances can be used. One or more of these can be used as reducing agents.

[0068] (After-purging and return to atmospheric pressure) After forming a predetermined film on the surface of the wafer 200, valves 243b and 243c are closed to stop the supply of raw materials and reducing agents into the processing chamber 201. Then, using the same processing procedures and conditions as in the purging in steps B and C, any remaining gaseous substances in the processing chamber 201 are removed from the processing chamber 201. After that, the atmosphere inside the processing chamber 201 is replaced with an inert gas, and the pressure inside the processing chamber 201 is returned to atmospheric pressure.

[0069] (Boat unloading and wafer discharge) The seal cap 219 is then lowered by the boat elevator 115, opening the lower end of the manifold 209. The processed wafers 200 are then discharged from the lower end of the manifold 209 to the outside of the reaction tube 203, supported by the boat 217. After being discharged from the outside of the reaction tube 203, the processed wafers 200 are removed from the boat 217.

[0070] (3) Effects of this embodiment According to this embodiment, one or more of the following effects can be obtained.

[0071] (a) In step B, an etching agent is supplied to the wafer 200. In step C, the sacrificial part 270 is reacted with the etching agent to generate a substance X that promotes the etching process on the wafer 200. This allows etching on the surface of the wafer 200 to be initiated by the reaction between the etching agent and substance X. Furthermore, by reacting the etching agent with substance X, the etching reaction is promoted, making it possible to efficiently etch the surface of the wafer 200.

[0072] In steps B and C, a trace amount of substance X(H) generated in step C is produced. ２ Although O) is consumed by reacting with the etching agent, a new substance X can be generated by etching the oxide using the etching species produced by this reaction. Therefore, in steps B and C, if a small amount of substance X is generated in step C, this can be used as a starting point to cause a chain reaction between the etching agent and substance X as described above, making it possible to repeatedly etch the surface of the wafer 200.

[0073] In step C, the etching agent is reacted with the sacrificial part 270 to produce substance X. This produces a much smaller amount of substance X compared to, for example, supplying substance X into the processing container via a nozzle. In this way, it is possible to avoid supplying excess substance X into the processing container that cannot be consumed during the execution of steps B and C, and thus avoid the impact of excess substance X on the film formation process in step D, which is performed after the execution of steps B and C.

[0074] (b) By providing the sacrificial part 270 outside the processing area R, the substance X produced by reacting the sacrificial part 270 with the etching agent, and the etching agent can be supplied to the wafer 200 from the side of the wafer 200. This makes it possible to improve the uniformity of the oxide etching process within the substrate surface.

[0075] (c) By providing the sacrificial part 270 between the nozzle 249a and the processing area R, material X can be reliably generated, and the generated material X and etching agent can be reliably supplied to the wafer 200. This ensures that etching on the surface of the wafer 200 can be reliably performed.

[0076] (d) The sacrificial part 270 is positioned closer to the processing area R than the nozzle 249a, allowing the substance X to be efficiently supplied to the wafer 200. This avoids the generation of particles caused by the substance X adsorbing into the processing container.

[0077] (e) The controller 121 controls the etching agent supply system that supplies the etching agent into the processing container via the nozzle 249a. This ensures that the above-mentioned effects are reliably obtained.

[0078] (f) In step B, the controller 121 controls the etching agent supply system so that the etching agent is supplied when the nozzle 249a, the sacrificial part 270, and the support column 213 are not positioned in a straight line. Also in step B, when the boat 217 is rotated by the rotating mechanism 267, the controller 121 controls the etching agent supply system and the rotating mechanism 267 so that the etching agent is supplied at a timing when the nozzle 249a, the sacrificial part 270, and the support column 213 are not positioned in a straight line. As a result, the material X generated in step C can be supplied to the wafer 200 without being obstructed by the support column 213, so that etching on the surface of the wafer 200 can be performed efficiently. ２ When configured in this way, the reaction between the etching agent and the support column 213 prevents the generation of substance X, thus avoiding the generation of particles caused by the adsorption of excess substance X into the processing container.

[0079] (g) The controller 121 is configured to control the boat elevator 115 and the parts elevator 215, respectively. In this way, by moving the sacrificial part 270 using the parts elevator 215, which has a different mechanism from the boat elevator 115, the location where material X is generated can be adjusted. This makes it possible to achieve fine etching.

[0080] (h) In steps B and C, the controller 121 controls the etching agent supply system and the parts elevator 215 to move the sacrificial parts 270 to predetermined positions for etching promotion and to supply the etching agent. This allows the sacrificial parts 270 to be placed in areas with low etching rates, such as areas within the processing area R where the etching agent is difficult to supply or areas with relatively high temperatures. As a result, etching in areas with low etching rates can be promoted, thereby improving the uniformity of oxide etching across substrates.

[0081] (i) In steps B and C, the controller 121 controls the parts elevator 215 and the etching agent supply system to perform the process of supplying the etching agent with the sacrificial part 270 in a first position and the process of supplying the etching agent with the sacrificial part 270 in a second position. This makes it possible to generate material X at different locations as needed. As a result, the location of material X generation can be finely adjusted, and the uniformity of the oxide etching process between substrates can be improved.

[0082] (j) In steps B and C, the controller 121 controls the parts elevator 215 and the etching agent supply system to supply the etching agent while moving the sacrificial part 270 between the first and second positions. This improves the uniformity of the oxide etching process between substrates.

[0083] (k) The controller 121 is configured to control the parts elevator 215 so as to move the sacrificial part 270 to a storage position different from the first and second positions after the etching process is completed. The vertical size of the sacrificial part 270 is such that when the sacrificial part 270 is stored in the storage position, at least a portion of the sacrificial part 270 does not protrude above the heat insulating plate 218 located at the top. This prevents, for example, raw materials supplied in step D, which is performed after the completion of steps B and C, from being supplied to the sacrificial part 270. As a result, a film is not formed on the sacrificial part 270, so that in the next step C as well, the sacrificial part 270 can function to generate material X. This improves the batch-to-batch uniformity of the etching process.

[0084] (l) In steps B and C, the controller 121 controls the parts elevator 215 and the etching agent supply system to supply the etching agent with the sacrificial part 270 positioned in a third position different from the first and second positions. This makes it possible to generate material X locally at the third position as needed, thereby improving the uniformity of the oxide etching process between substrates.

[0085] (m) The third position is located between the first and second positions, which allows for fine adjustment of the location where substance X is generated.

[0086] (n) A sacrificial part 270 is provided in the path through which the etching agent supplied to the wafer 200 in the processing area R flows, and which is capable of generating a substance X that reacts with the etching agent and promotes the etching process on the wafer 200. This ensures that the above-mentioned effects can be reliably obtained.

[0087] (o) A recess, such as a groove or indentation, is provided at a predetermined location on the surface of the sacrificial part 270. This increases the surface area of ​​the sacrificial part 270. By increasing the surface area of ​​the sacrificial part 270, the amount of reaction between the sacrificial part 270 and the etching agent can be increased. Also, for example, when the sacrificial part 270 is consumed by reacting with the etching agent and a hole is formed, it is highly likely that the hole will be formed at the bottom of a recess. In this way, the location where the hole will be formed can be estimated, and when the hole is formed, it can be easily detected. For this reason, for example, if the hole is used as an indicator for replacing the sacrificial part 270 with a new one, the sacrificial part 270 can be replaced without delay. Furthermore, since the sacrificial part 270 is configured to be removable from the parts elevator 215, the sacrificial part 270 can be easily replaced.

[0088] (p) The above-mentioned effects can also be obtained when a predetermined substance is arbitrarily selected from the various substances X, various etching agents, various raw materials, various reducing agents, and various inert gases mentioned above.

[0089] <Other Aspects of the Disclosure> The aspects of the Disclosure have been described in detail above. However, the Disclosure is not limited to the aspects described above and can be modified in various ways without departing from its essence.

[0090] In the above-described embodiment, the case in which the sacrificial part 270 is placed in the first position before the start of step B was explained as an example. However, for example, the sacrificial part 270 may be placed in the second or third position before the start of step B. The same effects as in the above-described embodiment can be obtained in this embodiment as well.

[0091] In the above-described embodiment, the case in which the sacrificial part 270 is moved once between the first position and the second position during the execution of steps B and C was explained as an example. However, for example, the sacrificial part 270 may be moved multiple times between the first position and the second position during the execution of steps B and C. The same effects as in the above-described embodiment can be obtained in this embodiment as well. Furthermore, in this embodiment, since the etching agent can be supplied inward from multiple locations on the outer circumference of the wafer 200, which is rotated by the rotating mechanism 267, during the execution of steps B and C, the uniformity of the oxide etching process within the substrate surface can be improved.

[0092] In the above-described embodiment, the case in which the sacrificial part 270 is moved between the first and second positions during the execution of steps B and C was explained as an example. However, for example, if the etching rate in the lower region is significantly smaller than the etching rate in the upper and middle regions, the sacrificial part 270 may be placed in the second position corresponding to the lower region before the start of step B, and it may not be necessary to move the sacrificial part 270 from the second position during the execution of steps B and C. In other words, it is not necessary to move the sacrificial part 270 between the first and second positions during the execution of steps B and C. The same effects as in the above-described embodiment can be obtained in this embodiment as well. In this embodiment, the operation of the parts elevator 215 can be further simplified.

[0093] Furthermore, for example, the etching rate in a region close to the exhaust port 231a that exhausts the atmosphere inside the processing chamber 201 (e.g., the lower region) may be higher than in other regions (upstream of the gas flow, e.g., the upper or middle region). This may occur because the amount (concentration) of substance X, which is generated upstream of the gas flow, increases as it flows downstream (towards the exhaust port 231a). In such cases, it is not necessary to place the sacrificial part 270 at a first position corresponding to the upper region before the start of step B, and to move the sacrificial part 270 from the first position during the execution of steps B and C. In other words, it is not necessary to move the sacrificial part 270 to a third or second position during the execution of steps B and C. The same effects as in the above-described embodiment can be obtained in this embodiment as well. In this embodiment, the operation of the parts elevator 215 can be further simplified.

[0094] For example, in step D, a material containing semiconductor elements other than Si may be used to form a semiconductor element-containing film on the wafer 200. For example, a material containing metal elements such as tungsten (W), molybdenum (Mo), aluminum (Al), titanium (Ti), zirconium (Zr), hafnium (Hf), and tantalum (Ta) may be used as a raw material to form a metal element-containing film on the substrate. In these cases as well, the same effects as those of the above-described embodiment can be obtained.

[0095] Furthermore, in step D, for example, instead of forming a film on the substrate, the surface of the wafer 200 may be modified to a predetermined surface, or the surface of the wafer 200 may be etched. In these cases as well, the same effects as in the above-described embodiment can be obtained.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 200 Wafer (substrate) 201 Processing container (processing chamber) 249a Nozzle 270 Sacrificial part

Claims

1. A substrate processing apparatus comprising: a processing container provided with a processing area for processing a substrate; an etching agent supply unit for supplying an etching agent to a substrate in the processing area; and a sacrificial part provided in a path through which the etching agent flows within the processing container, which reacts with the etching agent to generate a substance X that promotes the etching process on the substrate.

2. The substrate processing apparatus according to claim 1, wherein the sacrificial part is provided outside the processing area.

3. The substrate processing apparatus according to claim 1, wherein the sacrificial part is provided between the etching agent supply unit and the processing area.

4. The substrate processing apparatus according to claim 3, wherein the sacrificial part is located closer to the processing area than the etching agent supply unit.

5. The substrate processing apparatus according to claim 1, comprising: an etching agent supply system that supplies the etching agent into the processing container via the etching agent supply unit; and a control unit configured to control the etching agent supply system.

6. The substrate processing apparatus according to claim 5, wherein the processing container has a substrate support configured to support the substrate using pillars that hold the outer edge of the substrate, and the control unit is configured to control the etching agent supply system so that the etching agent is supplied in such a way that the etching agent supply unit, the sacrificial part, and the pillars are not located in a straight line.

7. The substrate processing apparatus according to claim 5, comprising: a substrate support configured to support the substrate using pillars that hold the outer edge of the substrate within the processing container; and a rotating unit for rotating the substrate support, wherein the control unit is configured to control the etching agent supply system and the rotating unit so as to supply the etching agent at a timing when the etching agent supply unit, the sacrificial part, and the pillars are not in a straight line when the substrate support is rotated by the rotating unit.

8. The substrate processing apparatus according to claim 5, comprising: a first lifting unit capable of raising and lowering a substrate support that supports the substrate; and a second lifting unit capable of raising and lowering the sacrificial part, wherein the control unit is configured to control the first lifting unit and the second lifting unit, respectively.

9. The substrate processing apparatus according to claim 8, wherein the control unit is configured to control the etching agent supply system and the second lifting unit so as to move the sacrificial part to a predetermined position for etching promotion and supply the etching agent.

10. The substrate processing apparatus according to claim 8, wherein the control unit is configured to control the second lifting unit and the etching agent supply system so as to perform the following processes: supplying the etching agent with the sacrificial part in a first position, and supplying the etching agent with the sacrificial part in a second position.

11. The substrate processing apparatus according to claim 10, wherein the control unit is configured to control the second lifting unit and the etching agent supply system so as to supply the etching agent while moving the sacrificial part between the first position and the second position.

12. The substrate processing apparatus according to claim 11, wherein the control unit is configured to control the second lifting unit so as to move the sacrificial part to a storage position different from the first and second positions after the etching process is completed.

13. The substrate processing apparatus according to claim 11, wherein the control unit is configured to control the second lifting unit and the etching agent supply system so as to supply the etching agent while moving the sacrificial part multiple times between the first position and the second position.

14. The substrate processing apparatus according to claim 11, wherein the control unit is configured to control the second lifting unit and the etching agent supply system so as to supply the etching agent while the sacrificial part is positioned in a third position different from the first and second positions.

15. The substrate processing apparatus according to claim 14, wherein the third position is provided between the first position and the second position.

16. A sacrificial part provided in a processing container having a processing area for processing a substrate, in a path through which an etching agent supplied to the substrate in the processing area flows, and capable of reacting with the etching agent to generate a substance X that promotes the etching process on the substrate.

17. A substrate processing method comprising: (a) a step of preparing a substrate in a processing area within a processing container; (b) a step of supplying an etching agent to the substrate in the processing area; and (c) a step of reacting a sacrificial part provided in a path through which the etching agent flows within the processing container with the etching agent to generate a substance X that promotes etching of the substrate.

18. A method for manufacturing a semiconductor device, comprising: (a) a step of preparing a substrate in a processing area within a processing container; (b) a step of supplying an etching agent to the substrate in the processing area; and (c) a step of reacting a sacrificial part provided in a path through which the etching agent flows within the processing container with the etching agent to generate a substance X that promotes etching of the substrate.

19. A program that causes a substrate processing apparatus to execute the following steps via computer: (a) a procedure for preparing a substrate in a processing area within a processing container; (b) a procedure for supplying an etching agent to the substrate in the processing area; and (c) a procedure for reacting a sacrificial part provided in the path through which the etching agent flows within the processing container with the etching agent to generate a substance X that promotes etching of the substrate.

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