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

Abstract

The present invention relates to a substrate processing method, a substrate processing apparatus, a recording medium, and a manufacturing method of a semiconductor device. The present invention can improve controllability of etching. It has: (a) a step of supplying a first gas containing a Group 14 element to a substrate on which a film containing a Group 14 element is formed, which is arranged in a processing container, in such a manner that a reaction by-product generated by a reaction with the Group 14 element contained in the film formed on the substrate is saturatedly adsorbed to the substrate; (b) a step of supplying a second gas containing a halogen after (a); and (c) a step of etching the film containing the Group 14 element formed on the substrate by alternately repeating (a) and (b).

Description

Technical Field

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

[0002] Sometimes, a raw material gas containing silane-based gas, chlorine-based or fluorine-based gas, and hydrogen-based gas are repeatedly supplied to a substrate with exposed silicon layer to grow a film on the silicon layer (see, for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2005-183514 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] The purpose of this disclosure is to provide techniques that can improve the controllability of etching.

[0008] Methods for solving problems

[0009] According to one aspect of this disclosure, the following technology is provided, which has:

[0010] (a) A process of supplying a first gas containing the Group 14 element to a substrate disposed in a processing container having a film containing a Group 14 element formed thereon, such that reaction byproducts generated by the reaction with the Group 14 element contained in the film formed on the substrate are saturated and adsorbed onto the substrate.

[0011] (b) the process of supplying a second gas containing halogens after (a); and

[0012] (c) A process of etching the film containing Group 14 elements formed on the substrate by alternating (a) and (b).

[0013] The effects of the invention

[0014] According to this disclosure, the controllability of etching can be improved. Attached Figure Description

[0015] [ Figure 1 [A schematic longitudinal cross-sectional view of a vertical processing furnace of a substrate processing apparatus according to one embodiment of this disclosure.]

[0016] [ Figure 2 ]for Figure 1 A rough cross-sectional view of line AA in the diagram.

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

[0018] [ Figure 4 [A diagram illustrating the substrate processing sequence in one embodiment of this disclosure.]

[0019] [ Figure 5 ] Figure 5 (A) Figure 5 (D) is used for... Figure 4 This is a schematic diagram illustrating the state of the substrate surface during the substrate processing sequence.

[0020] [ Figure 6 [A diagram illustrating a variation of the substrate processing sequence in one embodiment of this disclosure.]

[0021] [ Figure 7 [A diagram illustrating a variation of the substrate processing sequence in one embodiment of this disclosure.]

[0022] [ Figure 8 ] Figure 8 (A) and Figure 8 (B) is a diagram illustrating a variation of the substrate processing sequence in one embodiment of this disclosure.

[0023] [ Figure 9 ] Figure 9 (A) and Figure 9 (B) is a schematic longitudinal cross-sectional view of the processing furnace of the substrate processing apparatus in another embodiment of this disclosure.

[0024] Explanation of reference numerals in the attached figures

[0025] 10. Substrate processing apparatus; 121. Controller; 200. Wafers (substrates); 201. Processing chamber Detailed Implementation

[0026] See below. Figures 1-5 The following explanation is provided. It should be noted that the accompanying drawings used in the following explanation are schematic diagrams, and the dimensional relationships and ratios of the elements shown in the drawings may not necessarily be consistent with reality. Furthermore, the dimensional relationships and ratios of elements may not necessarily be consistent across multiple drawings.

[0027] (1) Composition of substrate processing device

[0028] The substrate processing apparatus 10 includes a processing furnace 202, which is equipped with a heater 207 as a heating means (heating mechanism, heating system). The heater 207 is cylindrical in shape and is vertically mounted by being supported on a heater base (not shown) as a holding plate.

[0029] Inside the heater 207, an outer tube 203 constituting a processing container is arranged concentrically with the heater 207. The outer tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed into a cylindrical shape with a closed upper end and an open lower end. Below the outer tube 203, a manifold (inlet flange) 209 is arranged concentrically with the outer tube 203. The manifold 209 is made of a metal such as stainless steel (SUS) and is formed into a cylindrical shape with open upper and lower ends. An O-ring 220a, serving as a sealing component, is provided between the upper end of the manifold 209 and the outer tube 203. The manifold 209 is supported on the heater base, thereby allowing the outer tube 203 to be installed vertically.

[0030] An inner tube 204 constituting a processing container is disposed inside the outer tube 203. The inner tube 204 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed into a cylindrical shape with a closed upper end and an open lower end. The processing container is mainly composed of the outer tube 203, the inner tube 204, and the manifold 209. A processing chamber 201 is formed in the hollow part of the processing container (inside the inner tube 204).

[0031] The processing chamber 201 is configured to house the wafer 200, which serves as a substrate, in a state in which multiple layers are arranged in a horizontal orientation along the vertical direction using the crystal boat 217 described later.

[0032] Inside the processing chamber 201, nozzles 410, 420, and 430 are provided so as to penetrate the side wall of the manifold 209 and the inner pipe 204. Gas supply pipes 310, 320, and 330 are respectively connected to the nozzles 410, 420, and 430. However, the processing furnace 202 of this embodiment is not limited to the above-described form.

[0033] Mass flow controllers (MFCs) 312, 322, and 332, serving as flow controllers (flow control units), are sequentially installed on gas supply pipes 310, 320, and 330, starting from the upstream side. Additionally, valves 314, 324, and 334, serving as on / off valves, are installed on gas supply pipes 310, 320, and 330, respectively. A gas supply pipe 340 is connected downstream of valve 324 in gas supply pipe 320. MFC 342 and valve 344 are sequentially installed on gas supply pipe 340, starting from the upstream side. Gas supply pipes 510, 520, and 530, supplying inactive gases, are connected downstream of valves 314, 324, and 334 in gas supply pipes 310, 320, and 330, respectively (further downstream of the confluence with gas supply pipe 340 in gas supply pipe 320). On the gas supply pipes 510, 520, and 530, starting from the upstream side, MFC512, 522, and 532, which serve as flow controllers (flow control units), and valves 514, 524, and 534, which serve as on / off valves, are respectively installed.

[0034] Nozzles 410, 420, and 430 are respectively connected to the front ends of gas supply pipes 310, 320, and 330. Nozzles 410, 420, and 430 are configured in the form of L-shaped nozzles, with their horizontal portions extending through the side wall of manifold 209 and inner tube 204. The vertical portions of nozzles 410, 420, and 430 are disposed inside a channel-shaped (groove-shaped) preparation chamber 201a, and are disposed upward along the inner wall of inner tube 204 (above the arrangement direction of wafers 200) within the preparation chamber 201a. The preparation chamber 201a is formed to protrude radially outward from inner tube 204 and extend vertically.

[0035] Nozzles 410, 420, and 430 are arranged to extend from the lower region to the upper region of the processing chamber 201, and multiple gas supply holes 410a, 420a, and 430a are respectively provided at positions opposite to the wafer 200. Thus, processing gas is supplied to the wafer 200 from the gas supply holes 410a, 420a, and 430a of the nozzles 410, 420a, and 430. Multiple gas supply holes 410a, 420a, and 430a are provided from the lower to the upper part of the inner tube 204, each having the same opening area and the same opening pitch. However, the gas supply holes 410a, 420a, and 430a are not limited to the above configuration. For example, the opening area can gradually increase from the lower part to the upper part of the inner tube 204. This allows for a more uniform flow rate of gas supplied from the gas supply holes 410a, 420a, and 430a.

[0036] Gas supply holes 410a, 420a, and 430a of nozzles 410, 420, and 430 are provided at a height from the lower to the upper part of the crystal boat 217 (described later). Therefore, processing gas supplied into the processing chamber 201 through the gas supply holes 410a, 420a, and 430a of nozzles 410, 420, and 430 is supplied to the entire area of ​​the wafer 200 housed in the crystal boat 217 from the lower to the upper part. Nozzles 410, 420, and 430 can be provided in a manner extending from the lower to the upper region of the processing chamber 201, but are preferably provided in a manner extending to near the top of the crystal boat 217.

[0037] The first gas containing Group 14 elements is supplied as a processing gas from the gas supply pipe 310 through MFC 312, valve 314, and nozzle 410 into the processing chamber 201.

[0038] Halogen-containing gas is supplied as a processing gas from gas supply pipe 320 through MFC 322, valve 324, and nozzle 420 into processing chamber 201.

[0039] Oxygen-containing gas is supplied as treatment gas from gas supply pipe 330 through MFC 332, valve 334, and nozzle 430 into treatment chamber 201.

[0040] Hydrogen-containing gas is supplied as a treatment gas from gas supply pipe 340 through MFC 342, valve 344, gas supply pipe 320, and nozzle 420 into treatment chamber 201.

[0041] In this disclosure, a gas composed of a combination of halogen-containing gas and hydrogen-containing gas supplied to the processing chamber 201 via nozzle 420 is used as the second gas.

[0042] Nitrogen (N2) gas, for example, is supplied as an inactive gas to the processing chamber 201 via gas supply pipes 510, 520, and 530, respectively, through MFCs 512, 522, and 532, valves 514, 524, and 534, and nozzles 410, 420, and 430. The following description uses N2 gas as an inactive gas, but in addition to N2 gas, rare gases such as argon (Ar), helium (He), neon (Ne), and xenon (Xe) can also be used as inactive gases.

[0043] The process gas supply system mainly consists of gas supply pipes 310, 320, 330, and 340, MFCs 312, 322, 332, and 342, valves 314, 324, 334, and 344, and nozzles 410, 420, and 430. However, nozzles 410, 420, and 430 can also be considered as part of the process gas supply system. The process gas supply system can be simply referred to as the gas supply system. When the first gas flows into the system through gas supply pipe 310, the first gas supply system mainly consists of gas supply pipe 310, MFC 312, and valve 314. Nozzle 410 can be considered as part of the first gas supply system. Alternatively, the first gas supply system can also be called a gas supply system containing Group 14 elements. Furthermore, when halogen-containing gas and hydrogen-containing gas flow from gas supply pipe 320, the halogen-containing gas supply system mainly consists of gas supply pipe 320, MFC 322, and valve 324; the hydrogen-containing gas supply system mainly consists of gas supply pipe 340, MFC 342, valve 344, and gas supply pipe 320; and the second gas supply system mainly consists of the halogen-containing gas supply system and the hydrogen-containing gas supply system. It is possible to include nozzle 420 in the second gas supply system. Similarly, when oxygen-containing gas flows from gas supply pipe 330, the oxygen-containing gas supply system mainly consists of gas supply pipe 330, MFC 332, and valve 334. It is possible to include nozzle 430 in the oxygen-containing gas supply system. Additionally, the inactive gas supply system mainly consists of gas supply pipes 510, 520, 530, MFCs 512, 522, 532, and valves 514, 524, and 534.

[0044] In the gas supply method disclosed herein, gas is supplied via nozzles 410, 420, and 430 disposed within a preparation chamber 201a (which is located within an annular longitudinal space defined by the inner wall of an inner tube 204 and the ends of multiple wafers 200). Furthermore, gas is ejected into the inner tube 204 from multiple gas supply holes 410a, 420a, and 430a located opposite the wafers on the nozzles 410, 420, and 430. More specifically, processing gas is ejected in a direction parallel to the surface of the wafer 200 through the gas supply holes 410a, 420a, and 430a of the nozzles 410, 420a, and 430a.

[0045] The exhaust port (vent) 204a is a through-hole formed on the side wall of the inner tube 204 opposite to the nozzles 410, 420, and 430. For example, it is a narrow slit-like through-hole that is elongated in the vertical direction. Gas supplied from the gas supply holes 410a, 420a, and 430a of the nozzles 410, 420, and 430 into the processing chamber 201 and flowing over the surface of the wafer 200 flows through the exhaust port 204a into the exhaust passage 206, which is formed by the gap between the inner tube 204 and the outer tube 203. Furthermore, the gas flowing into the exhaust passage 206 flows into the exhaust pipe 231 and is discharged out of the processing furnace 202.

[0046] The exhaust port 204a is positioned opposite to the plurality of wafers 200. Gas supplied from the gas supply ports 410a, 420a, and 430a to the vicinity of the wafers 200 in the processing chamber 201 flows horizontally and then flows into the exhaust path 206 through the exhaust port 204a. The exhaust port 204a is not limited to being configured as a slit-shaped through-hole, but may also be composed of multiple holes.

[0047] An exhaust pipe 231 for venting the atmosphere inside the processing chamber 201 is provided on the manifold 209. From upstream, the exhaust pipe 231 is sequentially connected to a pressure sensor 245 (a pressure detector, or pressure sensing unit) for detecting the pressure inside the processing chamber 201, an APC (Auto Pressure Controller) valve 243, and a vacuum pump 246 (a vacuum venting device). The APC valve 243 can perform vacuum venting and stop vacuum venting in the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operating. Furthermore, the pressure inside the processing chamber 201 can be adjusted by regulating the valve opening while the vacuum pump 246 is operating. The exhaust system mainly consists of an exhaust port 204a, an exhaust path 206, an exhaust pipe 231, an APC valve 243, and a pressure sensor 245. Including the vacuum pump 246 in the exhaust system is a viable option.

[0048] Below the manifold 209, a sealing cover 219, serving as a furnace opening cover, is provided to airtightly seal the lower opening of the manifold 209. The sealing cover 219 is configured to abut against the lower end of the manifold 209 from a vertical downward direction. The sealing cover 219 is made of a metal such as SUS and is formed in a disc shape. An O-ring 220b, serving as a sealing member, abuts against the lower end of the manifold 209 on the upper surface of the sealing cover 219. On the side of the sealing cover 219 opposite to the processing chamber 201, a rotation mechanism 267 is provided to rotate a wafer boat 217 containing the wafer 200. The rotation shaft 255 of the rotation mechanism 267 passes through the sealing cover 219 and is connected to the wafer boat 217. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the wafer boat 217. The sealing cover 219 is configured to move vertically upwards and downwards via a crystal boat lift 115, which is vertically mounted outside the outer tube 203 and serves as a lifting mechanism. The crystal boat lift 115 is configured to move the crystal boat 217 into and out of the processing chamber 201 by raising and lowering the sealing cover 219. The crystal boat lift 115 is configured as a transport device (transport system) for transporting the crystal boat 217 and the wafers 200 housed in the crystal boat 217 to and from the processing chamber 201.

[0049] The crystal boat 217, serving as a substrate support, is configured such that multiple wafers 200, for example 25 to 200 wafers 200, are arranged horizontally and aligned at their centers in a vertically spaced manner. The crystal boat 217 is made of a heat-resistant material such as quartz or SiC. At the lower part of the crystal boat 217, a heat insulation plate 218, made of a heat-resistant material such as quartz or SiC, is supported horizontally and in multiple layers (not shown). With this configuration, heat from the heater 207 is not easily conducted to the sealing cover 219 side. However, this embodiment is not limited to the above-described configuration. For example, the heat insulation plate 218 may not be provided at the lower part of the crystal boat 217; instead, a heat insulation cylinder made of a cylindrical component made of a heat-resistant material such as quartz or SiC may be provided.

[0050] like Figure 2 As shown, a temperature sensor 263, serving as a temperature detector, is installed inside the inner tube 204. The configuration is such that the electrical current supplied to the heater 207 is adjusted based on the temperature information detected by the temperature sensor 263, thereby achieving the desired temperature distribution within the processing chamber 201. The temperature sensor 263, like the nozzles 410, 420, and 430, is configured in an L-shape and is installed along the inner wall of the inner tube 204.

[0051] like Figure 3As shown, the controller 121, which serves as the control unit (control mechanism), 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. An input / output device 122, such as a touch panel, is connected to the controller 121.

[0052] The storage device 121c is configured with, for example, flash memory or an HDD (Hard Disk Drive). Within the storage device 121c, control programs that control the operation of the substrate processing apparatus and process flow diagrams describing the steps and conditions of the semiconductor device manufacturing method (described later) are stored in a readable manner. The process flow diagram is a combination of steps in the semiconductor device manufacturing method (described later) that enable the controller 121 to execute and obtain a predetermined result, and functions as a program. Hereinafter, the process flow diagram, control programs, etc., will also be referred to collectively as a program. In this specification, the term "program" is used in cases where only the process flow diagram is included, cases where only the control programs are included, or cases where a combination of both process flow diagrams and control programs is included. RAM 121b is configured as a storage area (working area) for temporarily holding programs, data, etc., read by the CPU 121a.

[0053] I / O port 121d is connected to the aforementioned MFC312, 322, 332, 342, 512, 522, 532, valves 314, 324, 334, 344, 514, 524, 534, pressure sensor 245, APC valve 243, vacuum pump 246, heater 207, temperature sensor 263, rotating mechanism 267, crystal boat lift 115, etc.

[0054] CPU 121a is configured to read and execute control programs from storage device 121c, and read processes from storage device 121c based on input of operation commands from input / output device 122. CPU121a is configured to control the following actions according to the read process information: various gas flow regulation actions using MFC312, 322, 332, 342, 512, 522, 532; opening and closing actions of valves 314, 324, 334, 344, 514, 524, 534; opening and closing actions of APC valve 243 and pressure regulation actions using APC valve 243 based on pressure sensor 245; temperature regulation actions of heater 207 based on temperature sensor 263; starting and stopping vacuum pump 246; rotation and rotation speed regulation actions of crystal boat 217 using rotating mechanism 267; lifting and lowering actions of crystal boat 217 using crystal boat lift 115; and the storage action of wafer 200 into crystal boat 217.

[0055] The controller 121 can be configured to install the aforementioned program stored in an external storage device (e.g., magnetic tape, floppy disk, hard disk, CD, DVD, MO, USB memory, memory card, etc.) 123 onto a computer. The storage device 121c and the external storage device 123 constitute a computer-readable recording medium. Hereinafter, they will also be referred to collectively as a recording medium. In this specification, the recording medium includes cases containing only the storage device 121c, cases containing only the external storage device 123, or cases containing both. The program can also be provided to the computer without using the external storage device 123, but using communication means such as the Internet or dedicated lines.

[0056] (2) Substrate processing process

[0057] use Figure 4 and Figure 5 (A) Figure 5 (D) will be described as an example of an etching process (etching method) in which a film containing group 14 elements, such as silicon (Si), is formed on a wafer 200 as part of a semiconductor device (equipment) manufacturing process. This process is performed using the processing furnace 202 of the substrate processing apparatus 10 described above. In the following description, the operation of each part constituting the substrate processing apparatus 10 is configured such that the controller 121 can control the operation of each part.

[0058] The substrate processing steps (semiconductor device manufacturing steps) based on this disclosure include:

[0059] (a) A process of supplying a first gas containing a group 14 element to a wafer 200 disposed in a processing container having a film containing a group 14 element formed thereon, such that reaction byproducts generated by the reaction with the group 14 element contained in the film formed on the wafer 200 are saturated and adsorbed onto the wafer 200.

[0060] (b) the process of supplying a second gas containing halogens after (a); and

[0061] (c) A process of etching a film containing Group 14 elements formed on wafer 200 by alternating (a) and (b).

[0062] In this specification, the term "wafer" is used to refer to both "the wafer itself" and "a laminate of a wafer and a specified layer or film formed on its surface." The term "surface of the wafer" is used to refer to both "the surface of the wafer itself" and "the surface of a specified layer, film, etc., formed on the wafer." The term "substrate" is used in the same way as "wafer."

[0063] (Chip loading)

[0064] If multiple wafers 200 are loaded (wafer filling) into the crystal boat 217, then as Figure 1 As shown, a crystal boat 217 supporting multiple wafers 200 is lifted by a crystal boat lift 115 and moved into the processing chamber 201 (crystal boat loading), and placed inside the processing container. In this state, the sealing cap 219 is closed by means of an O-ring 220 to seal the lower opening of the outer tube 203.

[0065] (Pressure and temperature regulation)

[0066] Vacuum pump 246 is used to exhaust vacuum, so that the space inside processing chamber 201, i.e., where wafer 200 is located, reaches the desired pressure (vacuum level). At this time, the pressure inside processing chamber 201 is measured by pressure sensor 245, and based on the measured pressure information, APC valve 243 is controlled by feedback (pressure regulation). Vacuum pump 246 remains operational at least until the processing of wafer 200 is completed. Additionally, heater 207 is used to heat the processing chamber 201 to a desired temperature. At this time, based on the temperature information detected by temperature sensor 263, the power supply to heater 207 is controlled by feedback (temperature regulation) to achieve the desired temperature distribution inside processing chamber 201. Heating of the processing chamber 201 using heater 207 continues at least until the processing of wafer 200 is completed.

[0067] (First gas supply (gas containing Group 14 elements), first step)

[0068] Open valve 314 to allow the first gas to flow into gas supply pipe 310. The first gas is regulated by MFC 312 and supplied into processing chamber 201 from gas supply port 410a of nozzle 410 and exhausted from exhaust pipe 231.

[0069] At this time, the first gas is supplied in such a way that the reaction byproducts generated by the reaction with the Group 14 element contained in the membrane containing Group 14 elements formed on the wafer 200 are saturated and adsorbed onto the wafer 200. Here, in this disclosure, "saturation" can mean that the adsorption sites are not completely filled, as long as it is substantially saturated. That is, in order to improve productivity, it can be a state of incomplete saturation, in other words, it can be a state of incomplete reaction. In addition, the following situation can also be referred to as saturated adsorption in this disclosure: in the combination of gas types and membrane types that have saturation curves in a region where the reaction amount is greater than a certain supply time, the state of incomplete saturation on the saturation curve is used. As long as it is a supply time on the saturation curve, at least one effect of this disclosure can be obtained. When the supply time is set in such a region where the supply time of the saturation curve can be obtained, it can also be called a supply utilizing the saturated adsorption characteristics.

[0070] Furthermore, at this time, the wafer 200 is supplied with an atmosphere for the decomposition of the first gas. The atmosphere for the decomposition of the first gas refers to a temperature in which the temperature of the wafer 200 is, for example, in the range of 350°C to 500°C. Specifically, when using, for example, dichlorosilane (SiH2Cl2, abbreviated as DCS) gas as the first gas, it is a temperature in the range of 350°C to 500°C.

[0071] That is, the temperature of the heater 207 is set to a temperature such that the temperature of the wafer 200 is within the range of, for example, 350 to 500°C. It should be noted that the expression "350 to 500°C" in this disclosure means that the range includes both the lower and upper limits. Therefore, for example, "350 to 500°C" means "above 350°C and below 500°C". The same applies to other numerical ranges.

[0072] Additionally, the APC valve 243 is adjusted at this time to bring the pressure inside the processing chamber 201 to, for example, a range of 20 to 100 Pa. The supply flow rate of the gas containing Group 14 elements, controlled by the MFC 312, is set to, for example, a range of 0.1 to 1.0 slm. The time for supplying the first gas to the wafer 200 is set to, for example, a range of 15 to 30 seconds.

[0073] As the first gas, for example, a gas containing silicon (Si), which is a group 14 element, a DCS gas, which is a chlorosilane gas, can be used.

[0074] Specifically, for example, when using DCS gas as the first gas and using a Si-based membrane (Si film) containing Group 14 elements, such as... Figure 5 As shown in (A), by supplying DCS gas, the DCS gas is adsorbed onto the wafer 200 (the substrate film on the surface) on which a Si film is formed in a decomposed state. At this time, the Si on the surface of the wafer 200 reacts with the Cl obtained from the decomposition of the DCS gas to generate SiCl as a reaction byproduct. In addition, the generated SiCl dissociates from the surface of the wafer 200, and the dissociated molecules polymerize.

[0075] Then, as Figure 5 As shown in (B), dissociated SiCl and polymerized molecules are re-adsorbed onto wafer 200. Regarding this re-adsorption, the number of adsorption sites decreases over time, leading to gradual saturation. This saturation is referred to as self-limitation. That is, a SiCl layer (inhibition layer) primarily composed of SiCl, such as SiCl2 and SiCl4, is formed on the surface of wafer 200. This SiCl layer inhibits the adsorption of newly supplied DCS gas, newly generated dissociated SiCl, and polymerized molecules; this effect is called the inhibition effect, and such a layer is called the inhibition layer. Here, with respect to undecomposed gases, SiCl formation is difficult, making it difficult to achieve the inhibition effect. That is, with respect to undecomposed gases, the following possibilities exist: physical adsorption of the gas molecules themselves occurs, the amount of physical adsorption continuously increases, and saturation is not reached; or the undecomposed gas reacts with the Si film, and etching continues without stopping. By supplying the decomposed DCS gas to the Si film on the wafer 200 in an atmosphere, the Cl contained in the DCS gas can react with the Si on the wafer 200, thereby promoting the formation of SiCl.

[0076] (Second gas supply (halogen-containing gas and hydrogen-containing gas), second step)

[0077] After a predetermined time has elapsed since the start of the first gas supply, valve 314 is closed, stopping the supply of the first gas to the processing chamber 201. At this time, valves 324 and 344 are opened, allowing halogen-containing gas and hydrogen-containing gas to flow simultaneously into the gas supply pipe 320. That is, after the first gas supply, the second gas supply begins without supplying purge gas.

[0078] The flow rates of halogen-containing gas and hydrogen-containing gas are regulated by MFC322 and 342, respectively, and supplied into the processing chamber 201 from the gas supply port 420a of nozzle 420 and exhausted from the exhaust pipe 231. At this time, a second gas is supplied to the wafer 200.

[0079] At this time, the wafer 200 is supplied with an atmosphere in which the second gas, a combination of halogen-containing gas and hydrogen-containing gas, does not decompose. An atmosphere in which the second gas does not decompose refers to a temperature in which the temperature of the wafer 200 is, for example, in the range of 350°C to 500°C. Specifically, if Cl2 gas is used as the second gas, it is a temperature in the range of 350°C to 500°C.

[0080] At this time, adjust APC valve 243 to bring the pressure inside processing chamber 201 to, for example, a range of 20 to 100 Pa. The supply flow rate of the halogen-containing gas, controlled by MFC 322, is set to, for example, a range of 0.01 to 0.10 slm. The supply flow rate of the hydrogen-containing gas, controlled by MFC 342, is set to, for example, a range of 0.1 to 2.0 slm. The time for simultaneously supplying the halogen-containing gas and the hydrogen-containing gas to the wafer 200 is set to, for example, a range of 2 to 5 seconds.

[0081] At this point, a mixture of halogen-containing gas and hydrogen-containing gas, known as the second gas, is supplied to the wafer.

[0082] For example, chlorine (Cl2) gas, which is a halogen-containing gas, and hydrogen (H2) gas, which is a hydrogen-containing gas, can be used as the second gas.

[0083] Specifically, for example, when using Cl2 gas and H2 gas as the second gas, such as Figure 5 As shown in (C), by supplying the second gas, a portion of the SiCl layer formed on the surface of wafer 200 reacts to generate reaction byproducts. Specifically, the Si contained in the SiCl layer bonds with the Cl contained in the Cl2 gas and the H contained in the H2 gas, resulting in the etching of the Si film on wafer 200. More specifically, the Si, Cl, and H molecules adsorbed on wafer 200 react with the Cl2 and H2 gases, which are the second gas, causing Si, Cl, and H to dissociate from the SiCl layer, thus etching the surface Si film. In other words, by not decomposing the second gas, Cl2 can be supplied to the SiCl layer formed on the surface of wafer 200 in the first step, improving the removal efficiency of the SiCl layer. This, in turn, improves the etching controllability of the Si film.

[0084] Here, when purging occurs between the first and second gas supplies, the SiCl adsorbed on the Si film surface is removed, exposing the Si film to be etched. This makes it difficult to obtain the etching characteristics of each layer, and the etching rate may decrease. By not purging between the first and second gas supplies, maintaining the Si film surface covered with SiCl as the target of etching, it is easier to obtain the etching effect of each layer. That is, it is possible to improve the etching rate and the in-plane uniformity of the etching.

[0085] (Blow-through, Step 3)

[0086] After a predetermined time, such as 1 to 30 seconds, following the start of the second gas supply, valves 324 and 344 are closed to stop the second gas supply. At this time, with the APC valve 243 of the exhaust pipe 231 open, vacuum pump 246 is used to evacuate the processing chamber 201, removing residual gas from the wafer 200 and expelling any unreacted second gas and reaction byproducts remaining in the processing chamber 201. Then, valves 514, 524, and 534 are opened to supply inactive gas as purge gas into the processing chamber 201, purging the processing container. The inactive gas, acting as purge gas, enhances the removal of residual gas from the wafer 200 and the expulsion of unreacted second gas and reaction byproducts remaining in the processing chamber 201. The supply flow rates of the inactive gas, controlled by MFCs 512, 522, and 532, are set to, for example, 0.1 to 2.0 slm.

[0087] Thus, by purging, it is possible to achieve... Figure 5 As shown in (D), reaction byproducts generated by etching are removed. Furthermore, in the case of cyclic processing, purging can suppress the reaction between the second gas and the reaction byproducts with the first gas. Additionally, it can suppress the weakening of the self-confining effect when supplying the first gas due to the reaction between the second gas and the reaction byproducts with the first gas. In other words, purging can improve the self-confining effect when supplying the first gas.

[0088] (Number of times specified)

[0089] By sequentially performing steps 1 to 3 as described above a predetermined number of times (N times, more than once), the film containing group 14 elements formed on the wafer 200 is etched. That is, by alternately repeating steps 1 to 3, the film containing group 14 elements formed on the wafer 200 can be etched.

[0090] (Post-purging and atmospheric pressure recovery)

[0091] Inert gases are supplied to the processing chamber 201 through gas supply pipes 510-530, and exhaust gases are discharged through exhaust pipe 231. The inert gases act as purge gases, thereby purging the processing chamber 201 and removing residual gases and reaction byproducts (post-purging). Then, the atmosphere in the processing chamber 201 is replaced with the inert gases (inert gas replacement), and the pressure in the processing chamber 201 is restored to atmospheric pressure (atmospheric pressure restoration).

[0092] (Chip removal)

[0093] Then, the sealing cover 219 is lowered using the crystal boat lift 115, opening the lower end of the outer tube 203. The processed wafer 200, supported by the crystal boat 217, is then moved from the lower end of the outer tube 203 to the outside of the outer tube 203 (crystal boat unloading). The processed wafer 200 is then removed from the crystal boat 217 (wafer removal).

[0094] (3) Effects of this implementation method

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

[0096] (a) It can improve the controllability of etching films containing Group 14 elements. (b) It can perform microfabrication of films containing Group 14 elements.

[0097] (4) Other implementation methods

[0098] The embodiments of this disclosure have been described in detail above. However, this disclosure is not limited to the above embodiments, and various modifications can be made without departing from its spirit.

[0099] (Variation Example 1)

[0100] Figure 6 This illustrates a variation of the substrate processing sequence in one embodiment of the present disclosure.

[0101] In this modified example, the film containing Group 14 elements formed on the wafer 200 is etched by sequentially performing steps 1 and 2 a predetermined number of times (N times or more). That is, the purging step 3 described above is not performed. In this case, the film containing Group 14 elements can also be etched.

[0102] (Variation Example 2)

[0103] Figure 7 This illustrates a variation of the substrate processing sequence in one embodiment of the present disclosure.

[0104] In this modified example, after performing steps 1 to 3 of the above-described cycle a predetermined number of times (N times), oxygen-containing gas is supplied by an oxygen-containing gas supply system. Then, after supplying an inert gas (purge gas), steps 1 to 3 of the above-described cycle are performed a predetermined number of times (M times). That is, oxygen-containing gas is supplied midway through the repetition of steps 1 to 3 to oxidize the surface. As a result, the surface of the wafer 200 is oxidized midway through etching, which can suppress excessive etching. In addition, the etching amount (etched film thickness) can be adjusted, which can improve the controllability of etching.

[0105] As an oxygen-containing gas, oxygen (O2), ozone (O3), water vapor (H2O), etc. can be used.

[0106] (Variation Example 3)

[0107] Figure 8 (A) and Figure 8 (B) represents a variation of the substrate processing sequence in one embodiment of this disclosure.

[0108] In this variation, such as Figure 8 As shown in (A), in addition to the gas containing Group 14 elements, hydrogen-containing gas is also supplied as the first gas in the first step described above. That is, hydrogen-containing gas is supplied in parallel with the supply of the gas containing Group 14 elements in the first step described above. Furthermore, halogen-containing gas is supplied as the second gas in the second step. That is, hydrogen-containing gas is not supplied in the second step.

[0109] In addition, such as Figure 8 As shown in (B), in both steps 1 and 2 above, in addition to supplying their respective gases, hydrogen-containing gas can also be supplied. That is, hydrogen-containing gas can be supplied in parallel with the gas supply containing Group 14 elements in step 1 and the halogen-containing gas supply in step 2, respectively.

[0110] That is, in either or both of steps 1 and 2, in addition to the respective gases supplied, a hydrogen-containing gas is also supplied. This allows each process to be carried out simultaneously with the removal of reaction byproducts, improving processing quality and etching control.

[0111] As a hydrogen-containing gas, hydrogen (H2) gas, activated hydrogen gas, etc. can be used.

[0112] (Variation Example 4)

[0113] Next, the etching effect described above will be explained in the following case: a film containing a Group 14 element, which is the object of etching, is made into a doped Si film doped with phosphorus (P) as a specified element and an undoped Si film without P. Steps 1 to 3 described above are performed on a wafer 200 on which the doped Si film and the undoped Si film are formed on the surface.

[0114] First, by supplying the first gas in step 1, the process described in step 1 occurs on both the doped Si film and the undoped Si film. Figure 5 (A) and Figure 5 The same reaction shown in (B).

[0115] Then, by supplying the second gas in step 2, the reaction is suppressed on the doped Si film compared to the reaction on the undoped Si film, while the reaction as described in step 2 occurs on the undoped Si film. Figure 5 The reaction shown in (C) is etched.

[0116] That is, by performing steps 1 to 3 above, undoped Si films can be selectively etched.

[0117] (Variation Example 5)

[0118] Next, the etching effect described above will be explained in the following case: a crystalline Si film containing a Group 14 element, which is the object of etching, is made into a single-crystal Si film or a polycrystalline Si film, and an amorphous Si film is made into an amorphous Si film. Steps 1 to 3 described above are performed on a wafer 200 on which the crystalline Si film and the amorphous Si film are formed.

[0119] Generally, amorphous Si films are easier to etch than crystalline Si films. That is, when etching according to the etching rate of crystalline Si films, amorphous Si films are sometimes etched beyond the specified film thickness, resulting in over-etching. This is believed to be because the etching rate varies depending on the grain boundaries and atomic arrangement of the crystals.

[0120] By performing steps 1 to 3 as described above, both the crystalline Si film and the amorphous Si film are etched. This is believed to be because, through a suppression effect, the etching using the first gas self-stops (saturation-stops), thus making it less susceptible to the difference in etching rate caused by crystallinity. In other words, according to this disclosure, the difference in etching rate between the crystalline Si film and the amorphous Si film can be reduced, and over-etching can be suppressed.

[0121] (Variation Example 6)

[0122] Next, the etching effect described above will be explained in the following case: a silicon oxide (SiO2) film containing a group 14 element as the etching target is made into an oxide film and a Si film as a non-oxide film, and the first to third steps described above are performed on a wafer 200 on which the SiO2 film and the Si film are formed.

[0123] By performing steps 1 to 3 as described above, the Si film, which is a non-oxide film, is etched. That is, the non-oxide film can be selectively etched. Here, in addition to the Si film, doped Si films with P doping, silicon nitride (SiN) films, etc., can also be used as the non-oxide film.

[0124] (Variation Example 7)

[0125] Next, the etching effect described above will be explained in the following case: a SiN film containing a Group 14 element, which is the object of etching, is made into a SiN film as a nitride film and a Si film as a non-nitride film, and the first to third steps described above are performed on a wafer 200 on which the SiN film and the Si film are formed.

[0126] By performing steps 1 to 3 as described above, the Si film, which is a non-nitride film, is etched. That is, the non-nitride film can be selectively etched.

[0127] (Variation Example 8)

[0128] Next, the etching effect described above will be explained in the following case: a Si film containing a Group 14 element, which is the object of etching, is made into a non-oxide film. Steps 1 to 3 described above are performed on a wafer 200 having the following stacked film, wherein the stacked film is formed by forming a non-oxide film Si film on a SiO2 film, which is an oxide film.

[0129] By performing steps 1 to 3 as described above, the Si film, which is a non-oxide film, is etched. That is, the SiO2 film, which is an oxide film, becomes an etching stopper, enabling selective etching of the non-oxide film.

[0130] It should be noted that the above embodiments describe a case where purging is not performed between the first gas supply and the second gas supply, but this disclosure is not limited to this, and purging may also be performed between the first gas supply and the second gas supply.

[0131] Furthermore, the above embodiments were described using the case where a Si film is used as a Si-containing film (containing a film of Group 14 elements) with Si as the main component. However, this disclosure is not limited to this. As a Si-containing film, single-crystal Si film, polycrystalline Si film, amorphous Si film, SiN film, doped Si film, undoped Si film, etc. can be used.

[0132] As a doped Si film, Si films doped with phosphorus (P) as a dopant or Si films doped with boron (B) as a dopant can be used.

[0133] In addition, the above embodiments can also be appropriately applied to cases where, for example, a membrane containing other Group 14 elements such as germanium (Ge) is used as a membrane containing Group 14 elements.

[0134] Furthermore, the above embodiments were described using the case where, for example, a DCS gas containing silicon (Si) is used as the first gas containing a gas of a Group 14 element. However, this disclosure is not limited to this and can also be appropriately applied to the case where a gas containing other Group 14 elements such as germanium (Ge) is used.

[0135] Specifically, as the first gas, for example, a chlorosilane-based gas containing at least one of dichlorosilane (SiH2Cl2, abbreviated as DCS), hexachlorodisilazane (Si2Cl6, abbreviated as HCDS), and silicon tetrachloride (SiCl4) can be used. Alternatively, silane-based gases such as silane (SiH4), disilazane (Si2H6), and trisilane (Si3H8) can be used. Chlorosilane-based gases containing Si and Cl, which readily undergo saturation reactions, are preferred. Furthermore, in the case of silane-based gases, the same effect as chlorosilane-based gases can be obtained by cyclic supply. That is, by leaving the halogen type of the second gas supplied in the Xth cycle to the (X+1)th cycle, the same effect can be obtained. Here, X is an integer.

[0136] Furthermore, as the first gas containing Ge, a chlorogermanane-based gas, such as one containing at least one of chlorogermanane (GeH2Cl2), hexachlorodigermanane (Ge2Cl6, also known as digermanium hexachloride), or germanium tetrachloride (GeCl4), can be used. Alternatively, germanane-based gases such as methanegermanane (GeH4), digermanane (Ge2H6), or trigermanane (Ge3H8) can be used. A chlorogermanane-based gas containing Ge and Cl, which readily undergoes a saturation reaction, is preferred. Furthermore, in the case of germanane-based gases, the same effect as with chlorogermanane-based gases can be obtained by cyclic supply. That is, by leaving the halogen type of the second gas supplied in the Xth cycle to the X+1th cycle, the same effect can be obtained. Here, X is an integer.

[0137] Furthermore, as the second gas, for example, a halogen-containing gas, chlorine (Cl2) gas, hydrogen chloride (HCl) gas, boron trichloride (BCl3) gas, silicon tetrachloride (SiCl4) gas, silane (SiH4) gas, and a mixture of Cl2 gas, or at least one of these gases combined with a hydrogen-containing gas, can be used. Additionally, H2 gas, etc., can be used as the hydrogen-containing gas.

[0138] Alternatively, as a second gas, for example, a combination of at least one of the following gases with a fluorine (F) gas or a bromine (Br) gas can be used, wherein the gas is a mixture of chlorine (Cl2) gas, hydrogen chloride (HCl) gas, boron trichloride (BCl3) gas, silicon tetrachloride (SiCl4) gas, silane (SiH4) gas and Cl2 gas.

[0139] In addition, by using a Cl-based gas containing chlorine as the second gas, the selectivity of etching can be improved. The same effect can be obtained when using F-based or Br-based gases.

[0140] Alternatively, as the second gas, silicon tetrachloride (SiCl4) gas and silane (SiH4) gas can be replaced with germanium tetrachloride (GeCl4) gas and germanane (GeH4) gas.

[0141] Furthermore, in the above embodiment, an example of supplying halogen-containing gas and hydrogen-containing gas into the processing chamber 201 via the same nozzle 420 has been described, but this disclosure is not limited thereto, and the gas may also be supplied from different nozzles.

[0142] Furthermore, the above embodiments describe an example of film formation using a batch vertical substrate processing apparatus that processes multiple substrates at a time, but this disclosure is not limited thereto and can also be appropriately applied to cases where film formation is performed using a monolithic substrate processing apparatus that processes one or more substrates at a time.

[0143] For example, this disclosure can also be appropriately applied to the use of [unclear text - possibly related to technology or technology]. Figure 9The substrate processing apparatus of the processing furnace 302 shown in (A) is used to form a film. The processing furnace 302 includes: a processing container 303 forming a processing chamber 301; a jet head 303s for supplying gas into the processing chamber 301 in a jet pattern; a support stage 317 for supporting one or more wafers 200 in a horizontal orientation; a rotation shaft 355 supporting the support stage 317 from below; and a heater 307 disposed in the support stage 317. A gas supply port 304a for supplying the first gas, a gas supply port 304b for supplying the second gas, and a gas supply port 304c for supplying the third gas are connected to the inlet (gas inlet) of the jet head 303s. A first gas supply system, the same as the first gas supply system of the above embodiment, is connected to the gas supply port 304a. A second gas supply system, the same as the second gas supply system of the above embodiment, is connected to the gas supply port 304b. An oxygen-containing gas supply system, identical to the oxygen-containing gas supply system described above, is connected to the gas supply port 304c. A gas dispersion plate is provided at the outlet (gas exhaust port) of the jet head 303s to supply gas into the processing chamber 301 in a jet pattern. An exhaust port 331 is provided in the processing container 303 for venting the gas from the processing chamber 301. An exhaust system, identical to the exhaust system described in the above embodiment, is connected to the exhaust port 331.

[0144] Additionally, for example, this disclosure can also be suitably applied to the use of [unclear text - possibly related to a specific application or technology]. Figure 9 The substrate processing apparatus of the processing furnace 402 shown in (B) is used to form a film. The processing furnace 402 includes: a processing container 403 for forming a processing chamber 401; a support stage 417 for horizontally supporting one or more wafers 200; a rotation shaft 455 supporting the support stage 417 from below; a lamp heater 407 for irradiating the wafers 200 in the processing container 403; and a quartz window 403w through which light from the lamp heater 407 passes. A gas supply port 432a for supplying the first gas, a gas supply port 432b for supplying the second gas, and a gas supply port 432c for supplying the oxygen-containing gas are connected to the processing container 403. A first gas supply system, the same as the first gas supply system of the above embodiment, is connected to gas supply port 432a. A second gas supply system, the same as the second gas supply system of the above embodiment, is connected to gas supply port 432b. An oxygen-containing gas supply system, the same as the oxygen-containing gas supply system of the above embodiment, is connected to gas supply port 432c. The processing container 403 is provided with an exhaust port 431 for venting exhaust from the processing chamber 401. An exhaust system identical to the exhaust system in the above embodiment is connected to the exhaust port 431.

[0145] When using the substrate processing apparatus described above, etching can also be performed in the same order and under the same processing conditions as in the above embodiment.

[0146] The process procedures (programs containing processing steps, processing conditions, etc.) used for the aforementioned substrate processing are preferably prepared individually (multiple procedures) according to the content of the substrate processing (film type, composition ratio, film quality, film thickness, processing steps, processing conditions, etc. of the thin film to be etched). Furthermore, it is preferable to appropriately select a suitable process procedure from among the multiple process procedures when starting the substrate processing, based on the content of the substrate processing. Specifically, it is preferable to pre-store (install) the multiple process procedures prepared individually according to the content of the substrate processing in the storage device 121c of the substrate processing apparatus via a telecommunication line and a recording medium (external storage device 123) containing the process procedures. Furthermore, it is preferable that when starting the substrate processing, the CPU 121a of the substrate processing apparatus appropriately selects a suitable process procedure from the multiple process procedures stored in the storage device 121c according to the content of the substrate processing. With this configuration, thin films of various film types, composition ratios, film qualities, and film thicknesses can be etched universally and with good reproducibility using a single substrate processing apparatus. In addition, it can reduce the operator's workload (input burden of processing steps, processing conditions, etc.), avoid operational errors, and enable rapid initiation of substrate processing.

[0147] Furthermore, this disclosure can also be implemented, for example, by changing the process technology of an existing substrate processing apparatus. In the case of changing the process technology, the process technology involved in this disclosure can also be installed in an existing substrate processing apparatus via a telecommunication line or a recording medium recording the process technology, or the input / output devices of an existing substrate processing apparatus can be operated to change its process technology itself to the process technology involved in this disclosure.

[0148] The above describes various typical embodiments of this disclosure, but this disclosure is not limited to these embodiments and can be used in appropriate combinations.

Claims

1. A substrate processing method, comprising: (a) A step of supplying a first gas containing silicon or germanium, which is a Group 14 element, to a membrane such that reaction byproducts generated by the reaction with the silicon or germanium contained in the membrane are saturated and adsorbed onto the surface of the membrane; and (b) The process of supplying a second gas containing halogens after (a), in, In (a), the first gas is supplied in an atmosphere in which the first gas decomposes; in (b), the second gas is supplied in an atmosphere in which the second gas does not decompose. The film containing silicon or germanium, which is a group 14 element, is etched by performing (a) and (b) a specified number of times.

2. The substrate processing method as described in claim 1, further comprising: The process of purging the processing container containing the substrate on which the film is formed after (b).

3. The substrate processing method as described in claim 1, which does not include: The process of purging the processing container containing the substrate on which the film is formed after (b).

4. The substrate processing method as described in claim 1, wherein, No purging is performed between (a) and (b).

5. The substrate processing method as described in claim 1, wherein, The first gas is a silane-based gas.

6. The substrate processing method as described in claim 1, wherein, The first gas is a chlorosilane-based gas.

7. The substrate processing method as described in claim 6, wherein, The chlorosilane gas is a gas containing at least one of dichlorosilane, hexachlorodisilane, and silicon tetrachloride.

8. The substrate processing method as described in claim 1, wherein, The halogen is a gas containing chlorine.

9. The substrate processing method as described in claim 8, wherein, The second gas is at least one of chlorine, hydrogen chloride, boron trichloride, silicon tetrachloride, silane, and a mixture of chlorine.

10. The substrate processing method as described in claim 1, wherein, The film containing silicon or germanium, which are elements of Group 14, has on its surface a silicon film doped with the specified element and a silicon film not doped with the specified element. The silicon film that is not doped with the specified elements is etched.

11. The substrate processing method as described in claim 1, wherein, The film containing silicon or germanium, which are elements of Group 14, has a crystalline silicon film and an amorphous silicon film on its surface. Both the crystalline silicon film and the amorphous silicon film are etched.

12. The substrate processing method as described in claim 1, wherein, The film containing silicon or germanium, which are elements of Group 14, has an oxide film and a non-oxide film on its surface. The non-oxidized film is etched.

13. The substrate processing method as described in claim 1, wherein, The film containing silicon or germanium, which are group 14 elements, has a nitrided film and a non-nitrided film on its surface. The non-nitride film is etched.

14. The substrate processing method as described in claim 1, wherein, Oxygen-containing gas is supplied between the specified number of times (a) and (b).

15. A substrate processing apparatus, comprising: A gas supply system that supplies a membrane containing silicon or germanium, which are Group 14 elements, with a first gas containing silicon or germanium, and a second gas containing halogens; and The control unit is configured to control the gas supply system to perform the following processes: (a) A process in which the first gas is supplied to the surface of the membrane in such a way that the reaction byproducts generated by the reaction with silicon or germanium, which are group 14 elements contained in the membrane, are saturated and adsorbed onto the surface of the membrane. (b) The process of supplying the second gas to the membrane after (a); In (a), the first gas is supplied under an atmosphere in which the first gas decomposes; in (b), the second gas is supplied under an atmosphere in which the second gas does not decompose; and The film containing silicon or germanium, which is a group 14 element, is etched by performing (a) and (b) a predetermined number of times.

16. A computer-readable recording medium containing a program that enables a processing device to perform the following steps using a computer: (a) The step of supplying a first gas containing silicon or germanium, which is a group 14 element, to a membrane such that reaction byproducts generated by the reaction with the silicon or germanium contained in the membrane as a group 14 element are saturated and adsorbed on the surface of the membrane. (b) The step of supplying a second gas containing halogens after (a); In step (a), the first gas is supplied under an atmosphere in which the first gas decomposes; and in step (b), the second gas is supplied under an atmosphere in which the second gas does not decompose; and The step of etching the film containing silicon or germanium, which is a group 14 element, by performing (a) and (b) a predetermined number of times.

17. A method for manufacturing a semiconductor device, comprising: (a) A step of supplying a first gas containing silicon or germanium, a group 14 element, to a substrate having a film formed thereon, such that reaction byproducts generated by the reaction of silicon or germanium, a group 14 element, contained in the film formed on the substrate, are saturated and adsorbed onto the substrate; and (b) The process of supplying a second gas containing halogens after (a), in, In (a), the first gas is supplied in an atmosphere in which the first gas decomposes; in (b), the second gas is supplied in an atmosphere in which the second gas does not decompose. The film containing silicon or germanium, which is a group 14 element, formed on the substrate is etched by performing (a) and (b) a predetermined number of times.

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