Method of processing substrate, method of manufacturing semiconductor device, substrate processing system, and program

Abstract

The present invention provides a technique for selectively forming a film with high precision on a desired surface. (a) (a1) a process of supplying an oxidizing agent and a reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state, (a2) a process of supplying a reducing agent to the substrate by exciting it into a plasma state, and (b) a process of heat-treating the substrate after (a) has been performed.

Description

Technology Field

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

[0002] As a process of manufacturing a semiconductor device, a treatment is performed to selectively grow and form a film on a specific surface among a plurality of surfaces of different materials exposed on the surface of a substrate (hereinafter, this treatment is also referred to as selective growth or selective film formation) (see, for example, Patent Documents 1 to 3). Prior art literature

[0003] Japanese Patent Publication No. 2021-106242 Japanese Patent Publication No. 2020-155452 Japanese Patent Publication No. 2020-155607 The problem to be solved

[0004] The present disclosure provides a technology for selectively forming a film with high precision on a desired surface. means of solving the problem

[0005] According to one aspect of the present disclosure,

[0006] (a) (a1) a process of supplying an oxidizing agent and a reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state, and (a2) a process of supplying a reducing agent to the substrate by exciting it into a plasma state, and

[0007] (b) A technology is provided that includes a process of heat-treating the substrate after (a) is performed. Effects of the invention

[0008] According to the present disclosure, it is possible to selectively form a film with high precision on a desired surface. Brief explanation of the drawing

[0009] FIG. 1 is a schematic diagram of a longitudinal processing furnace of a substrate processing apparatus suitably used in one embodiment of the present disclosure, and is a drawing showing the processing furnace (202) portion as a longitudinal cross-sectional view. FIG. 2 is a schematic diagram of a vertical processing furnace of a substrate processing apparatus suitably used in one embodiment of the present disclosure, and is a diagram showing the processing furnace (202) portion as a cross-sectional view along line AA of FIG. 1. FIG. 3 is a schematic diagram of a controller (121) of a substrate processing device suitablely used in one embodiment of the present disclosure, and is a block diagram showing the control system of the controller (121). FIG. 4 is a drawing illustrating a processing sequence in one embodiment of the present disclosure. FIG. 5(a) is an enlarged cross-sectional view of the surface of a substrate in which a stacked structure is formed by alternately stacking a first material (SiGe) and a second material (Si) on the surface, and a fourth material (SiO), a third material (SiN), and a fourth material (SiO) are stacked thereon, and a portion of the sidewall of the stacked structure of the first and second materials is removed so that a concave portion is formed in the sidewall of the stacked structure in a direction parallel to the surface of the substrate (transverse direction). FIG. 5(b) is an enlarged cross-sectional view of the surface of a substrate having the configuration of FIG. 5(a) on the surface, after forming an inhibitor layer by the processing sequence of the present embodiment. FIG. 5(c) is an enlarged cross-sectional view of the surface of a substrate having the configuration of FIG. 5(a) on its surface, after forming an inhibitor layer and then forming a film (SiOC) by the processing sequence of the present embodiment. FIG. 5(d) is an enlarged cross-sectional view of the surface of a substrate having the configuration of FIG. 5(a) on its surface, after forming an inhibitor layer and then forming a film (SiOC) by the processing sequence of the present embodiment, after performing heat treatment. FIG. 6(a) is an enlarged cross-sectional view of the surface of a substrate in which a stacked structure is formed by alternately stacking a first material (SiGe) and a second material (Si) on the surface, and a fourth material (SiO), a third material (SiN), and a fourth material (SiO) are stacked thereon, and a portion of the sidewall of the stacked structure of the first and second materials formed by the first material is removed, thereby providing a concave portion in the sidewall of the stacked structure in which the depth direction is parallel to the surface of the substrate (transverse direction). FIG. 6(b) is an enlarged cross-sectional view of the surface of a substrate having the configuration of FIG. 6(a) on the surface, after forming a film (SiOC) by a conventional film deposition method. Figure 6(c) is an enlarged cross-sectional view of the surface of a substrate after removing an excess film formed on the upper surface of a concave portion, etc., by performing an etching treatment on a substrate having the configuration of Figure 6(b) on its surface. FIG. 7 is a block diagram illustrating an example of a substrate processing system suitably used in another aspect of the present disclosure. FIG. 8 is a block diagram illustrating another example of a substrate processing system suitably used in another aspect of the present disclosure. Figure 9 is a cross-sectional TEM image of evaluation sample 1 in the example. Figure 10 is a cross-sectional TEM image of evaluation sample 2 in the example. Specific details for implementing the invention

[0010] <One aspect of the present disclosure>

[0011] Hereinafter, an embodiment of the present disclosure will be described with reference mainly to FIGS. 1 to 4 and FIGS. 5(a) to FIGS. 5(d). Furthermore, all drawings used in the following description are schematic, and the dimensional relationships of each element and the ratios of each element shown in the drawings do not necessarily correspond to reality. In addition, the dimensional relationships of each element and the ratios of each element do not necessarily correspond to one another among multiple drawings.

[0012] (1) Composition of a substrate processing device (substrate processing system)

[0013] As illustrated in FIG. 1, the processing furnace (202) has a heater (207) as a temperature regulator (heating part). The heater (207) is cylindrical in shape and is mounted vertically by being supported on a holding support plate. The heater (207) also functions as an activation mechanism (excitation part) that activates (excites) gas with heat.

[0014] Inside the heater (207), a reaction tube (203) is arranged concentrically with the heater (207). The reaction tube (203) is made of a heat-resistant material, such as quartz (SiO2) or silicon carbide (SiC), and is formed in a cylindrical shape with a closed top and an open bottom. Below the reaction tube (203), a manifold (209) is arranged concentrically with the reaction tube (203). The manifold (209) is made of a metal material, such as stainless steel (SUS), and is formed in a cylindrical shape with an open top and bottom. The upper end of the manifold (209) is connected to the lower end of the reaction tube (203) to support the reaction tube (203). An O-ring (220a) serving as a sealing member is provided between the manifold (209) and the reaction tube (203). The reaction tube (203) is mounted vertically, just like the heater (207). The processing vessel (reaction vessel) is mainly formed by the reaction tube (203) and the manifold (209). A processing chamber (201) is formed in the hollow portion of the processing vessel. The processing chamber (201) is configured to accommodate a wafer (200) as a substrate. Processing of the wafer (200) is performed within this processing chamber (201).

[0015] In the processing chamber (201), nozzles (249a to 249c) serving as first to third supply units are each provided to penetrate the side wall of the manifold (209). The nozzles (249a to 249c) are also referred to as the first to third nozzles. The nozzles (249a to 249c) are made of a heat-resistant material such as, for example, quartz or SiC. Gas supply pipes (232a to 232c) are each connected to the nozzles (249a to 249c). The nozzles (249a to 249c) are each different nozzles, and each nozzle (249a, 249c) is provided adjacent to the nozzle (249b).

[0016] In the gas supply pipes (232a to 232c), mass flow controllers (MFCs) (241a to 241c), which are flow controllers (flow control units), and valves (243a to 243c), which are open / close valves, are respectively provided in order from the upstream side of the gas flow. Gas supply pipes (232d, 232f) are respectively connected downstream from the valve (243a) of the gas supply pipe (232a). Gas supply pipes (232e, 232g) are respectively connected downstream from the valve (243b) of the gas supply pipe (232b). Gas supply pipe (232h) is connected downstream from the valve (243c) of the gas supply pipe (232c). In the gas supply pipes (232d to 232h), MFCs (241d to 241h) and valves (243d to 243h) are respectively provided in order from the upstream side of the gas flow. The gas supply pipes (232a to 232h) are made of a metal material such as, for example, SUS.

[0017] As shown in FIG. 2, nozzles (249a to 249c) are each provided to be erected upright in an annular space, viewed in a plane between the inner wall of the reaction tube (203) and the wafer (200), along the lower part of the inner wall of the reaction tube (203) and the upper part, toward the upward direction of the arrangement of the wafer (200). That is, nozzles (249a to 249c) are each provided to follow the wafer arrangement area in a region that horizontally surrounds the wafer arrangement area, on the side of the wafer arrangement area where the wafer (200) is arranged. In a plane, nozzle (249b) is arranged to be in a straight line opposite the exhaust port (231a) described later, with the center of the wafer (200) being brought into the processing room (201) in between. The nozzles (249a, 249c) are arranged so that a straight line (L) passing through the center of the nozzle (249b) and the exhaust port (231a) is inserted between both sides along the inner wall (outer periphery of the wafer (200)) of the reaction tube (203). The straight line (L) is also a straight line passing through the center of the nozzle (249b) and the wafer (200). That is, the nozzle (249c) may be provided on the opposite side of the nozzle (249a) with the straight line (L) in between. The nozzles (249a, 249c) are arranged symmetrically with the straight line (L) as the axis of symmetry. Gas supply holes (250a to 250c) for supplying gas are provided on the sides of the nozzles (249a to 249c), respectively. Each of the gas supply holes (250a to 250c) is opened to face the exhaust port (231a) when viewed in a planar view, so that it is possible to supply gas toward the wafer (200). The gas supply holes (250a to 250c) are provided in multiple numbers extending from the bottom to the top of the reaction tube (203).

[0018] From the gas supply pipe (232a), a reformer (reformed gas) is supplied into the processing chamber (201) through the MFC (241a), valve (243a), and nozzle (249a).

[0019] From the gas supply pipe (232b), a raw material (raw material gas) and a reducing agent (reducing gas), which are one of the film forming agents (film forming gas), are supplied into the processing chamber (201) through the MFC (241b), valve (243b), and nozzle (249b).

[0020] From the gas supply pipe (232c), a reaction agent (reaction gas), which is one of the film-forming agents (film-forming gas), is supplied into the processing chamber (201) through the MFC (241c), valve (243c), and nozzle (249c).

[0021] From the gas supply pipe (232d), a catalyst (catalytic gas), which is one of the film-forming agents (film-forming gas), is supplied into the processing chamber (201) through the MFC (241d), valve (243d), gas supply pipe (232a), and nozzle (249a).

[0022] From the gas supply pipe (232e), an etching agent (etching gas) and an oxidizing agent (oxidizing gas) are supplied into the processing chamber (201) through the MFC (241e), valve (243e), gas supply pipe (232b), and nozzle (249b).

[0023] From the gas supply pipes (232f to 232h), inert gas is supplied into the processing chamber (201) through the MFC (241f to 241h), valve (243f to 243h), gas supply pipes (232a to 232c), and nozzle (249a to 249c), respectively. The inert gas acts as a purge gas, carrier gas, dilution gas, etc.

[0024] A remote plasma unit (hereinafter RPU) (300) is provided on the downstream side of the connection portion between the gas supply pipe (232b) and the gas supply pipe (232g), which acts as a plasma excitation unit (plasma generation unit) for exciting the gas into a plasma state. Exciting the gas into a plasma state is also simply referred to as plasma excitation. By applying high frequency (RF) power to the RPU (300), it is possible to plasmaize and excite the gas inside the RPU (300), that is, to excite the gas into a plasma state. As for the plasma generation method, a capacitively coupled plasma (CCP) method may be used, or an inductively coupled plasma (ICP) method may be used. The RPU (300) is configured to be able to supply a reducing agent, an oxidizing agent, or an inert gas supplied from the gas supply pipes (232b, 232e, 232g) into a plasma state and supply it into the processing room (201).

[0025] A reformer supply system is mainly configured by a gas supply pipe (232a), an MFC (241a), and a valve (243a). A raw material supply system and a reducing agent supply system are mainly configured by a gas supply pipe (232b), an MFC (241b), and a valve (243b). A reactant supply system is mainly configured by a gas supply pipe (232c), an MFC (241c), and a valve (243c). A catalyst supply system is mainly configured by a gas supply pipe (232d), an MFC (241d), and a valve (243d). An etching agent supply system and an oxidizing agent supply system are mainly configured by a gas supply pipe (232e), an MFC (241e), and a valve (243e). An inert gas supply system is mainly configured by gas supply pipes (232f to 232h), an MFC (241f to 241h), and a valve (243f to 243h). The raw material supply system, the reactant supply system, or both are also referred to as the film-forming agent supply system. The raw material supply system, the reactant supply system, and the catalyst supply system, or both are also referred to as the film-forming agent supply system.

[0026] Any or all of the various supply systems described above may be configured as an integrated supply system (248) in which valves (243a to 243h) or MFCs (241a to 241h) are integrated. The integrated supply system (248) is connected to each of the gas supply pipes (232a to 232h) and configured so that the supply operation of various substances (various gases) into the gas supply pipes (232a to 232h), that is, the opening and closing operation of the valves (243a to 243h) or the flow rate adjustment operation by the MFCs (241a to 241h) is controlled by the controller (121) described later. The integrated supply system (248) is configured as an integrated or divided integrated unit, and can be attached to and detached from gas supply pipes (232a to 232h), etc., in an integrated unit manner, so that maintenance, replacement, expansion, etc. of the integrated supply system (248) can be performed in an integrated unit manner.

[0027] An exhaust port (231a) for exhausting the atmosphere inside the processing room (201) is provided on the lower side wall of the reaction tube (203). As shown in FIG. 2, the exhaust port (231a) is provided in a position facing the nozzles (249a to 249c) (gas supply holes (250a to 250c)) with the wafer (200) in between, when viewed in a planar view. The exhaust port (231a) may be provided along the upper side wall from the lower side of the reaction tube (203), that is, along the wafer arrangement area. An exhaust pipe (231) is connected to the exhaust port (231a). A vacuum pump (246) serving as a vacuum exhaust device is connected to the exhaust pipe (231) through a pressure sensor (245) serving as a pressure detector (pressure detection unit) for detecting pressure within the processing room (201) and an APC (Auto Pressure Controller) valve (244) serving as a pressure regulator (pressure adjustment unit). The APC valve (244) is configured to allow vacuum exhaust and vacuum exhaust stoppage within the processing room (201) by opening and closing the valve while the vacuum pump (246) is in operation, and also to allow pressure within the processing room (201) to be adjusted by controlling the valve opening degree based on pressure information detected by the pressure sensor (245) while the vacuum pump (246) is in operation. The exhaust system is mainly composed of the exhaust pipe (231), the APC valve (244), and the pressure sensor (245). The vacuum pump (246) may also be considered as part of the exhaust system.

[0028] Below the manifold (209), a seal cap (219) is provided as a cover capable of hermetically sealing the lower opening of the manifold (209). The seal cap (219) is made of a metal material such as SUS, for example, and is formed in a disc shape. On the upper surface of the seal cap (219), an O-ring (220b) is provided as a sealing member that contacts the lower end of the manifold (209). Below the seal cap (219), a rotation mechanism (267) for rotating the boat (217), which will be described later, is installed. The rotation axis (255) of the rotation mechanism (267) passes 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 raised vertically by a boat elevator (115) which is a lifting mechanism installed outside the reaction tube (203). The boat elevator (115) is configured as a conveying device (conveying mechanism) that brings the wafer (200) into and out of the processing room (201) by raising the seal cap (219).

[0029] Below the manifold (209), a shutter (219s) is provided as a cover that can hermetically seal the lower opening of the manifold (209) when the boat (217) is removed from the processing room (201) by lowering the seal cap (219). The shutter (219s) is made of a metal material, such as SUS, for example, and is formed in a disc shape. On the upper surface of the shutter (219s), an O-ring (220c) is provided as a sealing member that contacts the lower end of the manifold (209). The opening and closing operation (such as a lifting or rotating motion) of the shutter (219s) is controlled by a shutter opening and closing mechanism (115s).

[0030] The boat (217) serving as a substrate support is configured to support multiple wafers (200), for example, 25 to 200 wafers, in a horizontal position and aligned vertically, that is, arranged at intervals. The boat (217) is made of a heat-resistant material, for example, quartz or SiC. At the bottom of the boat (217), an insulating plate (218), made of a heat-resistant material, for example, quartz or SiC, is supported in multiple stages.

[0031] A temperature sensor (263) serving as a temperature detector is installed inside the reaction tube (203). By adjusting the degree of current flow to the heater (207) based on the temperature information detected by the temperature sensor (263), the temperature inside the processing room (201) becomes a desired temperature distribution. The temperature sensor (263) is provided along the inner wall of the reaction tube (203).

[0032] As illustrated in FIG. 3, the controller (121), which is a control unit (control means), is configured as a computer equipped with a CPU (Central Processing Unit) (121a), RAM (Random Access Memory) (121b), a memory device (121c), and an I / O port (121d). The RAM (121b), the memory device (121c), and the I / O port (121d) are configured to exchange data with the CPU (121a) through an internal bus (121e). An input / output device (122), configured as, for example, a touch panel, is connected to the controller (121). Additionally, it is possible to connect an external memory device (123) to the controller (121).

[0033] The memory device (121c) is composed of, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. Within the memory device (121c), a control program that controls the operation of the substrate processing device, and a process recipe containing the steps or conditions of the substrate processing described later, are readably recorded and stored. The process recipe is a combination of each step in the substrate processing described later, which is executed by the controller (121) on the substrate processing device (substrate processing system) to obtain a predetermined result, and functions as a program. Hereinafter, the process recipe and the control program, etc. are collectively referred to simply as a program. Also, the process recipe is simply referred to as a recipe. In this specification, when the term "program" is used, it may include only the recipe, only the control program, or both. The RAM (121b) is configured as a memory area (work area) where programs or data read by the CPU (121a) are temporarily stored.

[0034] The I / O port (121d) is connected to the above-described MFC (241a to 241h), valve (243a to 243h), pressure sensor (245), APC valve (244), vacuum pump (246), temperature sensor (263), heater (207), rotating mechanism (267), boat elevator (115), shutter opening / closing mechanism (115s), RPU (300), etc.

[0035] The CPU (121a) is configured to read and execute a control program from the memory device (121c), and also to read a recipe from the memory device (121c) in accordance with the input of an operation command 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 MFC (241a to 241h) according to the contents of the read recipe, the opening and closing operation of the valve (243a to 243h), the opening and closing operation of the APC valve (244) and the pressure adjustment operation by 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 rotation mechanism (267), the lifting operation of the boat (217) by the boat elevator (115), the opening and closing operation of the shutter (219s) by the shutter opening and closing mechanism (115s), and the plasma excitation operation of the gas by the RPU (300).

[0036] The controller (121) can be configured by installing the above-described program, which is recorded and stored in an external storage device (123), into a computer. The external storage device (123) includes, for example, a magnetic disk such as an HDD, an optical disk such as a CD, a magneto-optical disk such as an MO, a semiconductor memory such as a USB memory or an SSD. The storage device (121c) and the external storage device (123) are configured as computer-readable recording media. Hereinafter, these are 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. Furthermore, the provision of the program to the computer may be performed using communication means such as the internet or a dedicated line, without using the external storage device (123).

[0037] (2) Substrate processing process

[0038] A method for processing a substrate as a process of manufacturing a semiconductor device using the above-described substrate processing device (substrate processing system), that is, an example of a processing sequence for forming a film on the first surface among the first surface and the second surface of a wafer (200) as a substrate, is described mainly using FIGS. 4 and FIGS. 5 (a) to FIGS. 5 (d). Here, an example of a processing sequence for forming a film on the first surface among the first surface, the second surface, the third surface, and the fourth surface of the wafer (200) is described. In the following description, the operation of each part constituting the substrate processing device is controlled by a controller (121).

[0039] Here, as illustrated in FIG. 5(a), a concave portion is provided on the surface of a wafer (200), wherein the bottom surface is formed by a first material containing a first element, and the side and top surfaces are formed by a second material containing a second element different from the first element, and the depth direction is parallel to the surface of the wafer (200) (transverse direction). The first surface is the bottom surface of the concave portion, and the second surface is the side surface of the concave portion, or the side and top surface of the concave portion. Additionally, the third surface and the fourth surface are surfaces of parts different from the concave portion on the surface of the wafer (200). The third surface is formed by a third material containing a third element different from the first and second elements, and the fourth surface is formed by a fourth material containing a fourth element different from the first, second, and third elements. In addition, the first element includes a group 14 element, the second element includes a group 14 element, the third element includes a group 15 element, and the fourth element includes a group 16 element.

[0040] FIG. 5(a) illustrates an example in which the first element is germanium (Ge), the second element is silicon (Si), the third element is nitrogen (N), and the fourth element is oxygen (O), the first material is silicon germanium (SiGe), the second material is silicon (Si), the third material is silicon nitride (SiN), the fourth material is silicon oxide (SiO), and the wafer (200) is single crystal Si. That is, the first material includes the second element in addition to the first element. In addition, the third material includes the second element in addition to the third element. In addition, the fourth material includes the second element in addition to the fourth element. In addition, the wafer (200) includes the first element. That is, in this example, the first surface is composed of a silicon germanium film (SiGe film) as a germanium-containing film, the second surface is composed of a silicon film (Si film) as a silicon-containing film, the third surface is composed of a silicon nitride film (Si3N4 film, hereinafter also referred to as a SiN film) as a nitrogen-containing film, and the fourth surface is composed of a silicon oxide film (SiO2 film, hereinafter also referred to as a SiO film) as an oxygen-containing film.

[0041] More specifically, on the surface of the wafer (200), a stacked structure is provided in which a first material (SiGe) and a second material (Si) are alternately stacked, a third material (SiN) is provided above it, and a fourth material (SiO) is provided on top of it. Additionally, a fourth material (SiO) is provided between the stacked structure of the first material (SiGe) and the second material (Si) and the third material (SiN). That is, on the surface of the wafer (200), a stacked structure is provided in which a SiGe film and a Si film are alternately stacked, a SiO film is provided above it, a SiN film is provided above it, and a SiO film is provided on top of it. By removing a portion of the part formed by the SiGe film among the side walls of the stacked structure of the SiGe film and the Si film, a concave portion is provided in the side wall of the stacked structure such that the upper surface and the side surface are formed by the second material (Si) and the bottom surface is formed by the first material (SiGe), and the depth direction is a direction parallel to the surface of the wafer (200) (transverse direction). In addition, in the present specification, as shown in FIG. 5 (a), the part formed by the first material (SiGe) among the concave portions is referred to as the bottom surface, and based on that, the part formed by the second material (Si) among the concave portions that is in contact with the bottom surface and is provided perpendicular to the bottom surface is referred to as the side surface, and the part formed by the second material (Si) among the concave portions that is not in contact with the bottom surface and is provided parallel to the bottom surface is referred to as the upper surface.

[0042] In addition, the symbols A, A1, A2, B, C, D, E, and F in Fig. 4 represent steps A, A1, A2, B, C, D, E, and F described later, respectively, and the symbol P represents a fuzzy operation performed in steps other than step D.

[0043] The processing sequence shown in FIG. 4 includes Step A, which supplies an oxidizing agent and a reducing agent to a wafer (200) having a first surface and a second surface by exciting them into a plasma state, Step A2, which supplies a reducing agent to a wafer (200) by exciting them into a plasma state, and Step B, which heat-treats the wafer (200) after Step A is performed. Additionally, the wafer (200) further has at least one of a third surface and a fourth surface. FIG. 5(a) shows an example in which the wafer (200) has a first surface (surface of a SiGe film), a second surface (surface of a Si film), a third surface (surface of a SiN film), and a fourth surface (surface of a SiO film).

[0044] In addition, it is preferable to make the processing temperature in Step B higher than the processing temperature in Step A. In addition, it is preferable to make the processing temperature in Step B higher than the respective processing temperatures in Step A and Step C. In addition, it is preferable to make the processing temperature in Step B higher than the respective processing temperatures in Step A, Step C, and Step D. The processing sequence shown in FIG. 4 illustrates an example in which the processing temperature in Step B is higher than the processing temperature in Step A. In addition, the processing sequence shown in FIG. 4 illustrates an example in which the processing temperature in Step B is higher than the respective processing temperatures in Step A and Step C. In addition, the processing sequence shown in FIG. 4 illustrates an example in which the processing temperature in Step B is higher than the respective processing temperatures in Step A, Step C, and Step D. In the processing sequence shown in FIG. 4, for example, the processing temperature in Step B can be 100°C or higher and 400°C or lower.

[0045] In Step A, high-density hydroxyl group terminals (hereinafter also referred to as OH terminals or OH groups) are formed on the first surface and the second surface of the wafer (200), and in Step B, the OH terminals formed on the first surface are removed while leaving the high-density OH terminals formed on the second surface intact. More specifically, in Step A, high-density OH terminals are formed on at least one of the first surface, the second surface, the third surface, and the fourth surface of the wafer (200), and in Step B, the OH terminals formed on the first surface are removed while leaving the high-density OH terminals formed on at least one of the second surface, the third surface, and the fourth surface intact. Additionally, in the present embodiment, in Step A, high-density OH terminals are formed on the first surface, the second surface, and the third surface of the wafer (200). Since the fourth surface is composed of an SiO film, a sufficient amount of OH terminals is formed on the fourth surface even before performing Step A. However, if the OH terminals on the fourth surface are insufficient, the OH terminals on the fourth surface can be reinforced in Step A. Accordingly, in the present embodiment, by performing Step A, a state in which high-density OH terminals are formed on each of the first surface, the second surface, the third surface, and the fourth surface (a state in which each surface has high-density OH terminals) can be achieved, and by performing Step B, the OH terminals formed on the first surface can be removed while maintaining the state in which high-density OH terminals are formed on each of the second surface, the third surface, and the fourth surface (a state in which each surface has high-density OH terminals).

[0046] That is, in Step A, the first surface and the second surface are modified by oxidizing (plasma oxidation), and in Step B, the oxide formed on the first surface is removed by sublimation while leaving the oxide (oxide film) formed on the second surface intact. More specifically, in Step A, at least one of the first surface, the second surface, the third surface, and the fourth surface is modified by oxidizing, and in Step B, the oxide formed on the first surface is removed by sublimation while leaving the oxide formed on at least one of the second surface, the third surface, and the fourth surface intact. Furthermore, in the present embodiment, in Step A, the first surface, the second surface, and the third surface of the wafer (200) are modified by oxidizing. Since the fourth surface is composed of an SiO film, the fourth surface is not oxidized. However, if the fourth surface contains an element that is oxidized, the fourth surface can also be modified by oxidizing. Accordingly, in the present embodiment, by performing Step A, the first surface, the second surface, the third surface, and the fourth surface of the wafer (200) can each be oxidized (each surface having an oxide), and by performing Step B, the oxide formed on the first surface can be sublimated and removed while maintaining the oxidized state of the second surface, the third surface, and the fourth surface (each surface having an oxide). In addition, in Step A, the oxide formed on the first surface, the second surface, and the third surface of the wafer (200) is composed of a very thin and uniform layer or film-like material. This very thin and uniform layer or film-like oxide is also simply referred to as an oxide layer or oxide film.

[0047] By modifying each surface by oxidizing it as described above, high-density OH terminals can be formed on each surface. Additionally, by retaining (maintaining) the oxide on a specific surface, high-density OH terminals can be retained (maintained) on the specific surface. Furthermore, by removing the oxide on a specific surface by sublimating it, OH terminals on the specific surface can be removed. As a result, the second surface, the third surface, and the fourth surface before performing Step C are in a state having high-density OH terminals. Meanwhile, the first surface before performing Step C is in a state having no OH terminals, or having a much smaller amount of OH terminals than the amount of OH terminals on the second surface, the third surface, and the fourth surface.

[0048] Additionally, the processing sequence shown in FIG. 4 further includes step C, which forms an inhibitor layer on the second surface by supplying a modifier to the wafer (200) after step B has been performed. More specifically, in step C, an inhibitor layer is formed on at least one of the second surface, the third surface, and the fourth surface. Furthermore, in the present embodiment, an example is shown in which an inhibitor layer is formed on each of the second surface, the third surface, and the fourth surface, as illustrated in FIG. 5(b). In the present embodiment, a high-density inhibitor layer can be formed on each of the second surface, the third surface, and the fourth surface.

[0049] Additionally, the processing sequence shown in FIG. 4 further includes step D, which forms a film on the first surface by supplying a film-forming agent to the wafer (200) after step C is performed. Also, FIG. 5 (c) shows an example of filling the inside of a concave area with a film by selectively growing a film on the first surface among the first surface, second surface, third surface, and fourth surface.

[0050] More specifically, as illustrated in FIG. 4, in step D, a cycle is performed a predetermined number of times in which a raw material and a catalyst are supplied as a film-forming agent to the wafer (200) in step D1 and a reaction agent and a catalyst are supplied as a film-forming agent to the wafer (200) in step D2 are performed non-simultaneously. By doing so, a film is grown starting from the first surface, that is, the bottom surface of the concave portion, and the film is grown bottom-up within the concave portion so that the concave portion can be filled with the film.

[0051] In this specification, the above-described processing sequence may be represented as follows for convenience. The same notation is used in the descriptions of variations or other embodiments below. Also, "oxidizing agent * 」, 「Reducing agent * Notations such as 」 refer to an oxidizing agent and a reducing agent excited to a plasma state, respectively.

[0052] Oxidizing agent * +Reducing agent * → Reducing agent * → Heat treatment → Modifier → (Raw material + Catalyst → Reactant + Catalyst) × n

[0053] At this time, depending on the processing conditions, as shown in the processing sequence below, the catalyst may not be supplied, or the catalyst may be supplied to the wafer (200) in at least one of step D1 and step D2. FIG. 4 shows an example of supplying the catalyst to the wafer (200) in each of step D1 and step D2.

[0054] Oxidizing agent * +Reducing agent * → Reducing agent * → Heat treatment → Modifier → (Raw material → Reactant) × n

[0055] Oxidizing agent * +Reducing agent * → Reducing agent * → Heat treatment → Modifier → (Raw material + Catalyst → Reactant) × n

[0056] Oxidizing agent * +Reducing agent * → Reducing agent* → Heat treatment → Modifier → (Raw material → Reactant + Catalyst) × n

[0057] Oxidizing agent * +Reducing agent * → Reducing agent * → Heat treatment → Modifier → (Raw material + Catalyst → Reactant + Catalyst) × n

[0058] In addition, the processing sequence shown in FIG. 4 further includes a step E in which, after performing step D, the wafer (200) is heated to perform heat treatment, thereby performing post-treatment, i.e., post-treatment (hereinafter also referred to as PT), on the film formed to fill the concave portion.

[0059] Additionally, the processing sequence shown in FIG. 4 further comprises a step F in which, prior to performing step A, an etching agent is supplied to the wafer (200) to remove a natural oxide film formed on at least one of the first surface, the second surface, the third surface, and the fourth surface. Additionally, in the present embodiment, in step F, the natural oxide film formed on each of the first surface, the second surface, and the third surface can be removed.

[0060] In addition, in the present embodiment, the first surface is the surface of a SiGe film, the second surface is the surface of a Si film, the third surface is the surface of a SiN film, and the fourth surface is the surface of a SiO film. In step D, an example is described of growing a silicon oxycarbon film (SiOC film), which is one of the films containing silicon (Si), oxygen (O), and carbon (C), or a silicon oxide film (SiO film), which is one of the films containing silicon (Si) and oxygen (O).

[0061] The term "wafer" as used in this specification may refer to the wafer itself or to a laminate of the wafer and a predetermined layer or film formed on its surface. The term "surface of the wafer" as used in this specification may refer to the surface of the wafer itself or to the surface of a predetermined layer formed on the wafer. When the phrase "form a predetermined layer on the wafer" is described in this specification, it may mean forming a predetermined layer directly on the surface of the wafer itself or forming a predetermined layer on a layer formed on the wafer. When the term "substrate" is used in this specification, it is synonymous with the use of the term "wafer."

[0062] The term “agent” as used in this specification includes at least one of a gaseous substance and a liquid substance. The liquid substance includes a mist substance. That is, each of the etching agent, oxidizing agent, reducing agent, modifying agent, and film-forming agent (raw material, reactant, catalyst) may include a gaseous substance, may include a liquid substance such as a mist substance, or may include both.

[0063] The term "layer" as used in this specification includes at least one of a continuous layer and a discontinuous layer. For example, the inhibitor layer may include a continuous layer, a discontinuous layer, or both, provided that it is possible to produce a film-forming inhibitory effect (adsorption inhibitory effect, reaction inhibitory effect).

[0064] (Wafer charge and boat load)

[0065] When multiple wafers (200) are loaded (wafer charged) into the boat (217), the shutter (219s) is moved by the shutter opening / closing mechanism (115s), and the lower opening of the manifold (209) is opened (shutter open). After that, as shown in FIG. 1, the boat (217) supporting the multiple wafers (200) is lifted by the boat elevator (115) and brought into the processing room (201) (boat loaded). In this state, the seal cap (219) seals the lower end of the manifold (209) through the O-ring (220b). In this way, the wafers (200) are prepared in the processing room (201).

[0066] (Pressure adjustment and temperature adjustment)

[0067] After the boat load is finished, the space within the processing room (201), that is, the space where the wafer (200) exists, is vacuum-exhausted (reduced pressure exhaust) by a vacuum pump (246) so that the pressure (vacuum degree) inside the processing room (201) is reached. At this time, the pressure inside the processing room (201) is measured by a pressure sensor (245), and the APC valve (244) is feedback-controlled based on this measured pressure information. In addition, the wafer (200) inside the processing room (201) is heated by a heater (207) so that it reaches a desired processing temperature. At this time, the degree of current flow to the heater (207) is feedback-controlled based on temperature information detected by a temperature sensor (263) so that the temperature inside the processing room (201) reaches a desired temperature distribution. In addition, the rotation of the wafer (200) by a rotation mechanism (267) is initiated. The exhaust of the processing room (201), the heating of the wafer (200), and the rotation are all performed continuously at least until the processing of the wafer (200) is completed.

[0068] (Step F: Removal of natural oxide film)

[0069] After that, an etching agent is supplied to the wafer (200).

[0070] Specifically, the valve (243e) is opened to flow an etching agent (etching gas) into the gas supply pipe (232e). The etching agent is flow-regulated by the MFC (241e), supplied into the processing chamber (201) through the gas supply pipe (232b) and nozzle (249b), and exhausted from the exhaust port (231a). At this time, the etching agent is supplied to the wafer (200) from the side of the wafer (200) (etching agent supply). At this time, the valves (243f to 243h) may be opened to supply an inert gas into the processing chamber (201) through each of the nozzles (249a to 249c).

[0071] By supplying an etching agent to the wafer (200) under the processing conditions described below, the natural oxide film formed on the surface of the wafer (200) can be removed. That is, the natural oxide film on the first surface and the second surface of the wafer (200) can be removed. Specifically, the natural oxide film on the surface of a concave portion, where the top and side surfaces provided on the surface of the wafer (200) are composed of a Si film and the bottom surface is composed of a SiGe film, and the depth direction is parallel to the surface of the wafer (200) (transverse direction), can be removed. Additionally, the natural oxide film on the third surface of the wafer (200) can be removed. Specifically, the natural oxide film on the third surface, which is a surface different from the concave portion of the wafer (200) and is composed of a SiN film, can be removed. Additionally, since the fourth surface of the wafer (200) is composed of an SiO film, a natural oxide film is not formed on the fourth surface, but if a natural oxide film is formed on the fourth surface due to some factor, the natural oxide film can be removed.

[0072] As for the processing conditions when supplying the etching agent in Step F,

[0073] Treatment temperature: Room temperature (25℃) to 200℃, preferably 50 to 150℃

[0074] Processing pressure: 10 to 13332 Pa, 20 to 1333 Pa

[0075] Treatment time: 1 to 120 minutes, preferably 10 to 60 minutes

[0076] Etching agent supply flow rate: 0.05 to 5 slm, preferably 0.5 to 2 slm

[0077] Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm

[0078] This is an example.

[0079] In addition, the notation of a numerical range such as “25 to 200°C” in this specification means that the lower and upper limits are included within that range. Thus, for example, “25 to 200°C” means “25°C or higher and 200°C or lower.” The same applies to other numerical ranges. Furthermore, in this specification, processing temperature refers to the temperature of the wafer (200) or the temperature inside the processing room (201), and processing pressure refers to the pressure inside the processing room (201). Also, gas supply flow rate: 0slm means a case where the gas is not supplied. These also apply to the following description.

[0080] After removing the natural oxide film formed on the surface of the wafer (200), the valve (243e) is closed to stop the supply of etching agent into the processing chamber (201). Then, the processing chamber (201) is vacuum-evacuated to remove any remaining gaseous substances from the processing chamber (201). At this time, the valves (243f to 243h) are opened to supply an inert gas into the processing chamber (201) through the nozzles (249a to 249c). The inert gas supplied from the nozzles (249a to 249c) acts as a purge gas, thereby purging the processing chamber (201).

[0081] As for the processing conditions when performing purging in Step F,

[0082] Processing pressure: 1 to 30 Pa

[0083] Processing time: 1 to 120 seconds, preferably 1 to 60 seconds

[0084] Inert gas supply flow rate (per gas supply pipe): 0.5 to 20 slm

[0085] This is an example. In addition, it is preferable that the processing temperature when purging in this step be the same as the processing temperature when supplying the etching agent.

[0086] As an etching agent, for example, a fluorine (F)-containing gas may be used. As an F-containing gas, for example, chlorine trifluoride (ClF3) gas, chlorine fluoride (ClF) gas, nitrogen fluoride (NF3) gas, hydrogen fluoride (HF) gas, fluorine (F2) gas, etc. may be used. In addition, various cleaning solutions may be used as etching agents. For example, an aqueous HF solution may be used as an etching agent to perform DHF cleaning. In addition, for example, a cleaning solution containing ammonia water, hydrogen peroxide water, and pure water may be used as an etching agent to perform SC-1 cleaning (APM cleaning). In addition, for example, a cleaning solution containing hydrochloric acid, hydrogen peroxide water, and pure water may be used as an etching agent to perform SC-2 cleaning (HPM cleaning). In addition, for example, a cleaning solution containing sulfuric acid and hydrogen peroxide water may be used as an etching agent to perform SPM cleaning. One or more of these can be used as etching agents.

[0087] As an inert gas, noble gases such as nitrogen (N2), argon (Ar), helium (He), neon (Ne), and xenon (Xe) can be used. This applies to each step described below as well. As an inert gas, one or more of these can be used.

[0088] (Step A: Plasma Treatment)

[0089] After that, step A1, in which an oxidizing agent and a reducing agent are excited to a plasma state and supplied to the wafer (200), and step A2, in which a reducing agent is excited to a plasma state and supplied to the wafer (200), are performed sequentially.

[0090] [Step A1: First Plasma Treatment]

[0091] In step A1, an oxidizing agent and a reducing agent are excited to a plasma state and supplied to the wafer (200).

[0092] Specifically, valves (243e, 243b) are opened to flow an oxidizing agent and a reducing agent, respectively, into the gas supply pipes (232e, 232b). The oxidizing agent and the reducing agent, respectively, have their flow rates adjusted by MFCs (241e, 241b), are mixed within the gas supply pipe (232b), are excited into a plasma state by the RPU (300), are supplied into the processing chamber (201) through the nozzle (249b), and are exhausted from the exhaust port (231a). At this time, the oxidizing agent and the reducing agent, excited into a plasma state with respect to the wafer (200), are supplied from the side of the wafer (200) (oxidizing agent * +Reducing agent *Supply). In this way, it becomes possible to supply an oxidizing agent and a reducing agent to the wafer (200) by exciting them into a plasma state, and thereby supply oxygen (O)-containing radicals or hydrogen (H)-containing radicals to the wafer (200). These radicals may include O radicals, H radicals, or OH radicals. A treatment using an oxidizing agent and a reducing agent excited into a plasma state may be described as a treatment that includes at least one of plasma oxidation treatment, oxidizing agent plasma treatment (oxygen plasma treatment, etc.), plasma reduction treatment, reducing agent plasma treatment (hydrogen plasma treatment), and plasma oxidation-reduction treatment. At this time, the valves (243f to 243h) may be opened to supply an inert gas into the treatment chamber (201) through each of the nozzles (249a to 249c), or the inert gas may not be supplied.

[0093] Under the processing conditions described below, by supplying an oxidizing agent and a reducing agent to the wafer (200) in a plasma state, OH terminals can be formed on the first surface and the second surface of the wafer (200) after removing the natural oxide film. More specifically, OH terminals can be formed on at least any one of the first surface, the second surface, the third surface, and the fourth surface of the wafer (200) after removing the natural oxide film. In addition, in the present embodiment, OH terminals can be formed on the first surface, the second surface, and the third surface of the wafer (200) after removing the natural oxide film. Since the fourth surface is composed of an SiO film, a sufficient amount of OH terminals is formed on the fourth surface before performing this step. However, if the OH terminals on the fourth surface are insufficient, the OH terminals on the fourth surface can be reinforced in this step. Accordingly, in the present embodiment, by performing this step, it is possible to have OH terminals formed on each of the first surface, second surface, third surface, and fourth surface of the wafer (200) after removing the natural oxide film (a state in which each surface has OH terminals).

[0094] That is, by supplying an oxidizing agent and a reducing agent to the wafer (200) in a plasma state under the processing conditions described below, the first surface and the second surface of the wafer (200) after removing the natural oxide film can be oxidized (plasma oxidation). More specifically, at least one of the first surface, the second surface, the third surface, and the fourth surface of the wafer (200) after removing the natural oxide film can be oxidized. In addition, in the present embodiment, the first surface, the second surface, and the third surface of the wafer (200) after removing the natural oxide film can be oxidized. Since the fourth surface is composed of an SiO film, the fourth surface is not oxidized. However, if the fourth surface contains an element that causes oxidation, the fourth surface can also be oxidized. Accordingly, in the present embodiment, by performing this step, the first surface, the second surface, the third surface, and the fourth surface of the wafer (200) after removing the natural oxide film can be oxidized (each surface having an oxide). And by doing so, the first surface, the second surface, the third surface, and the fourth surface of the wafer (200) after removing the natural oxide film can be formed with OH terminals (each surface having OH terminals). Furthermore, as described above, the oxide formed on the first surface, the second surface, and the third surface of the wafer (200) is composed of a very thin and uniform layer or film-like material.

[0095] In addition, by performing this step, an oxide film (oxide), such as a silicon oxide film (SiO film), a germanium oxide film (GeO film), or a silicon germanium oxide film (SiGeO film), is formed on the first surface formed by the SiGe film, and OH terminals are formed on the surface. In addition, an oxide film (oxide), such as a SiO film, is formed on the second surface formed by the Si film, and OH terminals are formed on the surface. In addition, an oxide film (oxide), such as a SiO film or a silicon oxynitride film (SiON film), is formed on the third surface formed by the SiN film, and OH terminals are formed on the surface. The fourth surface formed by the SiO film maintains its state, so that the state in which OH terminals are formed on the surface is maintained, or the OH terminals on the surface are reinforced.

[0096] As for the treatment conditions when supplying the oxidizing agent and reducing agent in a plasma state in Step A1,

[0097] Treatment temperature: Room temperature (25℃) to 300℃, preferably room temperature to 200℃

[0098] Processing pressure: 1 to 10,000 Pa, preferably 50 to 1,000 Pa

[0099] Processing time: 1 to 1000 seconds, preferably 60 to 500 seconds

[0100] Oxidizer supply flow rate: 0.01 to 1 slm, preferably 0.1 to 0.5 slm

[0101] Reducing agent supply flow rate: 0.01 to 1 slm, preferably 0.1 to 0.5 slm

[0102] Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm

[0103] RF power: 1 to 10,000W, preferably 100 to 5,000W

[0104] is exemplified.

[0105] OH terminals are formed on the first surface, the second surface, and the third surface of the wafer (200), and after the OH terminals are formed on each of the first surface, the second surface, the third surface, and the fourth surface, the valves (243e, 243b) are closed to stop the supply of the oxidizing agent and the reducing agent into the processing chamber (201). Then, gaseous substances remaining in the processing chamber (201) are removed from the processing chamber (201) by the same processing procedure and processing conditions as the purging in Step F (purging). In addition, it is preferable that the processing temperature when performing purging be the same as the processing temperature when supplying the oxidizing agent and the reducing agent by exciting them into a plasma state.

[0106] As an oxidizing agent, for example, an oxygen (O)-containing gas may be used. As an O-containing gas, for example, oxygen (O2) gas, ozone (O3) gas, water vapor (H2O) gas, hydrogen peroxide (H2O2) gas, nitrous oxide (N2O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, carbon monoxide (CO) gas, carbon dioxide (CO2) gas, etc. may be used. As an oxidizing agent, one or more of these may be used.

[0107] As a reducing agent, for example, a hydrogen (H) containing gas such as hydrogen (H2) gas or a deuterium (D) containing gas such as deuterium (D2) gas may be used. As a reducing agent, one or more of these may be used. This point is also the same in Step A2 described later.

[0108] [Step A2: Second Plasma Treatment]

[0109] After Step A1 is completed, Step A2 is performed. In Step A2, a reducing agent is supplied to the wafer (200) by exciting it into a plasma state.

[0110] Specifically, the valve (243b) is opened to flow a reducing agent into the gas supply pipe (232b). The reducing agent is flow-regulated by the MFC (241b), excited into a plasma state by the RPU (300), supplied into the processing chamber (201) through the nozzle (249b), and exhausted from the exhaust port (231a). At this time, the reducing agent excited into a plasma state is supplied to the wafer (200) from the side of the wafer (200) (reducing agent * Supply). In this way, it becomes possible to supply a reducing agent to the wafer (200) by exciting it into a plasma state, and thereby supply hydrogen (H)-containing radicals to the wafer (200). The H-containing radicals may include H radicals. A treatment using a reducing agent excited into a plasma state may be described as a treatment that includes at least one of a plasma reduction treatment and a reducing agent plasma treatment (hydrogen plasma treatment). At this time, the valves (243f to 243h) may be opened to supply an inert gas into the treatment chamber (201) through each of the nozzles (249a to 249c), or the inert gas may not be supplied.

[0111] By supplying a reducing agent to the wafer (200) in a plasma state under the processing conditions described below, the first surface and the second surface of the wafer (200) having OH terminals formed thereon are subjected to the reducing agent * It can be modified by plasma treatment using [the agent]. More specifically, at least one of the first surface, the second surface, the third surface, and the fourth surface of the wafer (200) having OH ends formed thereon is a reducing agent * It can be modified by plasma treatment using [the agent]. In addition, in the present embodiment, the first surface, the second surface, the third surface, and the fourth surface of the wafer (200) in a state where OH ends are formed (a state having OH ends) are each treated with a reducing agent. *It can be modified by plasma treatment using [the method]. By doing so, impurities such as carbon (C) or nitrogen (N) that may be contained on each surface can be removed, thereby increasing the purity of the oxide film (oxide) on each surface and improving the state of the OH terminals. By doing so, the density of the OH terminals (Si-OH terminals) on each surface can be increased, thereby creating a state where each surface has high-density OH terminals. That is, by performing Step A1 and Step A2, it becomes possible to create a state where each of the first surface, second surface, third surface, and fourth surface of the wafer (200) has high-density OH terminals.

[0112] At this time, since an oxide film (oxide) is formed on each surface, each surface is not directly exposed to the plasma-excited reducing agent, i.e., H-containing radicals, and it becomes possible to prevent plasma damage to the underlying layers (SiGe film, Si film, SiN film, SiO film) constituting each surface. Furthermore, if Step A2 is performed before Step A1, since an oxide film (oxide) is not formed on each surface when Step A2 is performed, each surface becomes directly exposed to the plasma-excited reducing agent, i.e., H-containing radicals. As a result, the underlying layers (SiGe film, Si film, SiN film, SiO film) constituting each surface may suffer plasma damage. In particular, the Si film constituting the second surface tends to be more susceptible to plasma damage than other surfaces, and its shape may change upon exposure to H-containing radicals. In contrast, according to the present embodiment, the oxide film (oxide) formed on each surface in step A1 acts as a protective film (block film, barrier film), making it possible to prevent plasma damage to the substrates (SiGe film, Si film, SiN film, SiO film) constituting each surface.

[0113] As for the treatment conditions when supplying the reducing agent by exciting it into a plasma state in Step A2,

[0114] Treatment temperature: Room temperature (25℃) to 300℃, preferably room temperature to 200℃

[0115] Processing pressure: 1 to 10,000 Pa, preferably 50 to 1,000 Pa

[0116] Processing time: 1 to 1000 seconds, preferably 60 to 500 seconds

[0117] Reducing agent supply flow rate: 0.01 to 1 slm, preferably 0.1 to 0.5 slm

[0118] Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm

[0119] RF power: 1 to 10,000W, preferably 100 to 5,000W

[0120] is exemplified.

[0121] The first surface, the second surface, the third surface, and the fourth surface of the wafer (200) having OH ends, respectively, are each a reducing agent * After modification by plasma treatment using [the agent], the valve (243b) is closed to stop the supply of the reducing agent into the treatment chamber (201). Then, the gaseous substance remaining in the treatment chamber (201) is removed from the treatment chamber (201) by the same treatment procedure and treatment conditions as the purging in Step F (purging). In addition, it is preferable that the treatment temperature when performing purging be the same as the treatment temperature when supplying the reducing agent by exciting it into a plasma state.

[0122] As a reducing agent, for example, a reducing agent similar to the various reducing agents exemplified in Step A1 above may be used.

[0123] (Step B: Heat Treatment)

[0124] After Step A is completed, Step B is performed. In Step B, heat treatment (annealing treatment) is performed on the wafer (200) after Step A is performed. Additionally, in Step B, the output of the heater (207) is adjusted so that the temperature of the wafer (200) is raised to a state higher than the temperature of the wafer (200) in Step A, preferably higher than the temperature of the wafer (200) in Step A, and that state is maintained.

[0125] Specifically, for example, as illustrated in FIG. 4, in Step B, the temperature of the wafer (200), i.e., the processing temperature, is made higher than the processing temperature in Step A. Furthermore, as illustrated in FIG. 4, it is preferable to make the processing temperature in Step B higher than the respective processing temperatures in Step A and Step C, and furthermore, it is preferable to make the processing temperature in Step B higher than the respective processing temperatures in Step A, Step C, and Step D, and furthermore, it is preferable to make the processing temperature in Step B higher than the respective processing temperatures in Step A, Step C, Step D, and Step F. Hereinafter, the processing temperature in Step B is also simply referred to as the heat treatment temperature.

[0126] In addition, as shown in FIG. 4, Step B may be performed in parallel with the purging performed after Step A (Step A2). That is, in Step B, heat treatment may be performed on the wafer (200) while supplying an inert gas into the processing chamber (201).

[0127] In this case, valves (243f to 243h) are opened to flow inert gas into gas supply pipes (232a to 232c), respectively. The inert gas is flow-regulated by MFCs (241f to 241h), supplied into the processing chamber (201) through nozzles (249a to 249c), and exhausted from the exhaust port (231a). At this time, inert gas is supplied to the wafer (200) from the side of the wafer (200). However, after the purging performed after Step A (Step A2) is sufficiently performed, inert gas may not be supplied into the processing chamber (201) in Step B.

[0128] By performing heat treatment on the wafer (200) under the processing conditions described below, the OH terminals formed on the first surface of the wafer (200) can be removed while retaining the high-density OH terminals formed on the second surface of the wafer (200). More specifically, the OH terminals formed on the first surface of the wafer (200) can be removed while retaining the high-density OH terminals formed on at least one of the second surface, the third surface, and the fourth surface of the wafer (200). Furthermore, in the present embodiment, the OH terminals formed on the first surface of the wafer (200) can be removed while maintaining the state in which high-density OH terminals are formed on each of the second surface, the third surface, and the fourth surface of the wafer (200) (a state in which each surface has high-density OH terminals). Additionally, there may be cases where not all of the OH terminals formed on the first surface of the wafer (200) are removed, and only a very small portion thereof remains.

[0129] That is, by performing heat treatment on the wafer (200) under the processing conditions described below, the oxide (GeO film, etc.) formed on the first surface of the wafer (200) can be removed by sublimation while leaving the oxide formed on the second surface of the wafer (200) intact. More specifically, the oxide formed on at least one of the second surface, the third surface, and the fourth surface of the wafer (200) can be removed by sublimation while leaving the oxide formed on at least one of them intact. Furthermore, in the present embodiment, the oxide formed on the first surface of the wafer (200) can be removed by sublimation while maintaining the oxidized state (state in which each surface has oxide) of the second surface, the third surface, and the fourth surface of the wafer (200). Additionally, there may be cases where not all of the oxide formed on the first surface of the wafer (200) is removed, and only a very small portion thereof remains.

[0130] In this way, among the first surface, second surface, third surface, and fourth surface of the wafer (200), the oxide formed on the first surface can be selectively sublimated and removed because, under the processing conditions described later, the oxide, such as the GeO film formed on the first surface, is easier to sublimate than the oxide formed on the second surface, third surface, or fourth surface. Under the processing conditions described later, the oxide, such as the GeO film formed on the first surface, can be sublimated, while the oxide formed on the second surface, third surface, or fourth surface can be prevented from being sublimated. That is, under the processing conditions described later, it is possible to perform heat treatment under processing conditions in which the oxide, such as the GeO film formed on the first surface, is sublimated, and the oxide formed on the second surface, third surface, or fourth surface is not sublimated.

[0131] By retaining oxides on the second surface, third surface, and fourth surface of the wafer (200), high-density OH terminals on the second surface, third surface, and fourth surface can be retained, and by removing oxides on the first surface of the wafer (200) by sublimation, OH terminals on the first surface can be removed. Accordingly, the second surface, third surface, and fourth surface before performing Step C are in a state having high-density OH terminals. Meanwhile, the first surface before performing Step C is in a state having no OH terminals, or having a much smaller amount of OH terminals than the amount of OH terminals on the second surface, third surface, and fourth surface. That is, the amount (density, concentration) of OH terminals on the second surface, third surface, and fourth surface before performing Step C can be made to be greater (higher) than the amount (density, concentration) of OH terminals on the first surface. In addition, the amount (density, concentration) of OH terminals on the first surface can be made zero.

[0132] As for the treatment conditions when performing heat treatment on the wafer (200) in Step B,

[0133] Treatment temperature (heat treatment temperature): 100 to 400°C, preferably 100 to 350°C, more preferably 100 to 300°C

[0134] Processing pressure: 1 to 10,000 Pa, preferably 1 to 2,000 Pa

[0135] Treatment time: 1 to 180 minutes, preferably 10 to 60 minutes

[0136] Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm

[0137] This is an example.

[0138] If the heat treatment temperature is set to less than 100°C, the oxide formed on the first surface of the wafer (200) may not sublimate sufficiently, and thus the oxide may not be sufficiently removed. By setting the heat treatment temperature to 100°C or higher, the oxide formed on the first surface of the wafer (200) can be sufficiently sublimated and thus sufficiently removed.

[0139] If the heat treatment temperature is set to a temperature exceeding 400°C, at least some of the OH terminals on the second, third, and fourth surfaces of the wafer (200) may be detached and removed, and the density of OH terminals on these surfaces may decrease. In this case, the film formation inhibition effect (adsorption inhibition effect, reaction inhibition effect) by the inhibitor layer formed on the second, third, and fourth surfaces of the wafer (200) in Step C may decrease, and the selectivity in selective growth in Step D may decrease. By setting the heat treatment temperature to 400°C or lower, the detachment and removal of OH terminals on the second, third, and fourth surfaces of the wafer (200) can be sufficiently suppressed, and the decrease in the density of OH terminals on these surfaces can be sufficiently suppressed. In this case, in Step C, sufficient film inhibition effect by the inhibitor layer formed on the second surface, third surface, and fourth surface of the wafer (200) can be obtained, thereby sufficiently securing selectivity in selective growth in Step D. By setting the heat treatment temperature to 350°C or lower, the detachment and removal of OH terminals on the second surface, third surface, and fourth surface of the wafer (200) can be effectively suppressed, thereby effectively suppressing the decrease in density of OH terminals on these surfaces. By setting the heat treatment temperature to 300°C or lower, the detachment and removal of OH terminals on the second surface, third surface, and fourth surface of the wafer (200) can be suppressed more effectively, thereby more effectively suppressing the decrease in density of OH terminals on these surfaces.

[0140] In this regard, in Step B, it is desirable to set the heat treatment temperature to 100°C or higher and 400°C or lower, preferably 100°C or higher and 350°C or lower, and more preferably 100°C or higher and 300°C or lower.

[0141] While maintaining the state in which the second surface, the third surface, and the fourth surface of the wafer (200) each have OH terminals, the OH terminals formed on the first surface of the wafer (200) are removed, and then, by the same processing procedure and processing conditions as the purging in Step F, the gaseous substances remaining in the processing chamber (201) are removed from the processing chamber (201) (purging). In addition, the processing temperature when purging is preferably the same as the processing temperature when heat treatment is performed on the wafer (200), but it may be a different temperature from the processing temperature when heat treatment is performed on the wafer (200).

[0142] (Step C: Formation of inhibitor layer)

[0143] After Step B is completed, Step C is performed. In Step C, a modifier is supplied to the wafer (200) after Step B is performed.

[0144] Specifically, the valve (243a) is opened to flow a modifier into the gas supply pipe (232a). The modifier is flow-regulated by the MFC (241a), supplied into the processing chamber (201) through the nozzle (249a), and exhausted from the exhaust port (231a). At this time, the modifier is supplied to the wafer (200) from the side of the wafer (200) (modifier supply). At this time, the valves (243f to 243h) may be opened to supply an inert gas into the processing chamber (201) through each of the nozzles (249a to 249c). In addition, in step C, the output of the heater (207) is adjusted so that the temperature of the wafer (200) is lower than the temperature of the wafer (200) in step B, preferably lower than the temperature of the wafer (200) in step B, and the state is maintained.

[0145] By supplying a modifier to the wafer (200) under the processing conditions described below, as shown in FIG. 5 (b), at least a portion of the molecular structure of the molecule constituting the modifier can be selectively (preferably) adsorbed at a high density on the second surface, third surface, and fourth surface among the first surface, second surface, third surface, and fourth surface of the wafer (200), thereby forming a high-density inhibitor layer on the second surface, third surface, and fourth surface. Specifically, by suppressing the adsorption of at least a portion of the molecular structure of the molecule constituting the modifier on the first surface, and reacting the modifier with the high-density OH groups terminating the second surface, third surface, and fourth surface, it becomes possible to selectively adsorb at least a portion of the molecular structure of the molecule constituting the modifier at a high density on the second surface, third surface, and fourth surface. By doing so, it becomes possible to terminate the second surface, the third surface, and the fourth surface at a high density by at least a part of the molecular structure of the molecule constituting the modifier. In this way, the second surface, the third surface, and the fourth surface can be modified.

[0146] The inhibitor layer formed in this step comprises at least a portion of the molecular structure of a molecule constituting the modifier, which is a residue derived from the modifier. In Step D described later, the inhibitor layer prevents the adsorption of the raw material (film-forming agent) onto the second surface, the third surface, and the fourth surface, thereby inhibiting (suppressing) the progress of the film-forming reaction on the second surface, the third surface, and the fourth surface.

[0147] As at least part of the molecular structure of the molecule constituting the modifier, examples include trialkylsilyl groups such as trimethylsilyl groups (Si-Me3) or triethylsilyl groups (Si-Et3). Trialkylsilyl groups include alkyl groups, that is, hydrocarbon groups. In these cases, the Si of the trimethylsilyl group or triethylsilyl group is chemically adsorbed at high density on the second surface, third surface, and fourth surface of the wafer (200), so that the outermost surfaces of the second surface, third surface, and fourth surface are terminated at high density by alkyl groups such as methyl groups or ethyl groups, that is, hydrocarbon groups. Alkyl groups (alkylsilyl groups), such as methyl groups (trimethylsilyl groups) or ethyl groups (triethylsilyl groups), i.e., hydrocarbon groups, which are densely terminated on the second surface, third surface, and fourth surface, act as an inhibitor layer (film inhibition layer, adsorption inhibition layer, reaction inhibition layer) that prevents the adsorption of raw materials on the second surface, third surface, and fourth surface during the film formation treatment (selective growth) described later, thereby inhibiting the progress of the film formation reaction on the second surface, third surface, and fourth surface.

[0148] In addition, in this step, at least a portion of the molecular structure of the molecule constituting the modifier is adsorbed on a part of the first surface of the wafer (200), but the amount of adsorption is small, and the amount of adsorption on the second surface, third surface, and fourth surface of the wafer (200) is overwhelmingly larger. This selective (preferential) adsorption is possible because the processing conditions in this step are set so that the modifier does not undergo gaseous decomposition within the processing chamber (201). In addition, while the second surface, third surface, and fourth surface are OH-terminated at high density throughout, a large area of ​​the first surface is not OH-terminated. In this step, since the modifier does not undergo gaseous decomposition within the processing chamber (201), at least a portion of the molecular structure of the molecules constituting the modifier is not deposited multiplely on the first surface, second surface, third surface, and fourth surface, and at least a portion of the molecular structure of the molecules constituting the modifier is selectively adsorbed at high density on the second surface, third surface, and fourth surface, thereby selectively terminating at high density by at least a portion of the molecular structure of the molecules constituting the modifier.

[0149] As for the treatment conditions when supplying the modifier in Step C,

[0150] Treatment temperature: Room temperature (25℃) to 500℃, preferably room temperature to 250℃

[0151] Processing pressure: 5 to 2000 Pa, preferably 10 to 1000 Pa

[0152] Processing time: 1 second to 120 minutes, preferably 30 seconds to 60 minutes

[0153] Modifier supply flow rate: 0.001 to 3 slm, preferably 0.001 to 0.5 slm

[0154] Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm

[0155] This is an example.

[0156] After optionally forming a high-density inhibitor layer on the second, third, and fourth surfaces of the wafer (200), the valve (243a) is closed to stop the supply of the modifier into the processing chamber (201). Then, by the same processing procedure and processing conditions as the purging in Step F, the gaseous substance remaining in the processing chamber (201) is removed from the processing chamber (201) (purging). Additionally, it is preferable that the processing temperature when performing the purging be the same temperature as the processing temperature when supplying the modifier.

[0157] As a modifying agent, for example, a compound having a structure in which an amino group is directly bonded to Si, or a compound having a structure in which an amino group and an alkyl group are directly bonded to Si can be used.

[0158] As modifiers, for example, (dimethylamino)silane ((CH3)2NSiH3), (diethylamino)silane ((C2H5)2NSiH3), (dipropylamino)silane ((C3H7)2NSiH3), (dibutylamino)silane ((C4H9)2NSiH3), (dimethylamino)trimethylsilane ((CH3)2NSi(CH3)3), (diethylamino)triethylsilane ((C2H5)2NSi(C2H5)3), (dimethylamino)triethylsilane ((CH3)2NSi(C2H5)3), (diethylamino)trimethylsilane ((C2H5)2NSi(CH3)3), (dipropylamino)trimethylsilane ((C3H7)2NSi(CH3)3), (dibutylamino)trimethylsilane ((C4H9)2NSi(CH3)3), (Trimethylsilyl)amine ((CH3)3SiNH2), (triethylsilyl)amine ((C2H5)3SiNH2), etc. can be used. In addition, as a modifying agent, for example, bis(dimethylamino)dimethylsilane ([(CH3)2N]2Si(CH3)2), bis(diethylamino)diethylsilane ([(C2H5)2N]2Si(C2H5)2), bis(dimethylamino)diethylsilane ([(CH3)2N]2Si(C2H5)2), bis(diethylamino)dimethylsilane ([(C2H5)2N]2Si(CH3)2), bis(dimethylamino)silane ([(CH3)2N]2SiH2), bis(diethylamino)silane ([(C2H5)2N]2SiH2), bis(dimethylaminodimethylsilyl)ethane ([(CH3)2N(CH3)2Si]2C2H6), bis(dipropylamino)silane ([(C3H7)2N]2SiH2), Bis(dibutylamino)silane ([(C4H9)2N]2SiH2), bis(dipropylamino)dimethylsilane ([(C3H7)2N]2Si(CH3)2), bis(dipropylamino)diethylsilane ([(C3H7)2N]2Si(C2H5)2), (dimethylsilyl)diamine ((CH3)2Si(NH2)2), (diethylsilyl)diamine ((C2H5)2Si(NH2)2), (dipropylsilyl)diamine ((C3H7)2Si(NH2)2), bis(dimethylaminodimethylsilyl)methane ([(CH3)2N(CH3)2Si]2CH2), bis(dimethylamino)tetramethyldisilane ([(CH3)2N]2(CH3)4Si2), etc. may also be used.One or more of these may be used as modifiers.

[0159] (Step D: Tabernacle Processing (Selective Growth))

[0160] After Step C is completed, Step D is performed. In Step D, a film-forming agent is supplied to the wafer (200) after Step C is performed. Additionally, in Step D, the output of the heater (207) is adjusted so that the temperature of the wafer (200) is lower than or equal to the temperature of the wafer (200) in Step C, and while maintaining that state, Steps D1 and D2 are executed sequentially.

[0161] [Step D1: Formation of the first layer]

[0162] In Step D1, raw material (raw material gas) and catalyst (catalyst gas) are supplied as film-forming agents to the wafer (200) after Step C is performed, that is, the wafer (200) after which a high-density inhibitor layer is optionally formed on the second surface, the third surface, and the fourth surface.

[0163] Specifically, valves (243b, 243d) are opened to flow raw materials and catalysts, respectively, into gas supply pipes (232b, 232d). The flow rates of the raw materials and catalysts are each controlled by MFCs (241b, 241d), supplied into the processing chamber (201) through nozzles (249b, 249a), mixed within the processing chamber (201), and exhausted from the exhaust port (231a). At this time, raw materials and catalysts are supplied to the wafer (200) from the side of the wafer (200) (raw materials + catalyst supply). At this time, valves (243f to 243h) may be opened to supply inert gas into the processing chamber (201) through nozzles (249a to 249c), respectively.

[0164] By supplying raw materials and catalysts to the wafer (200) under the processing conditions described below, it becomes possible to selectively (preferably) chemically adsorb at least a portion of the molecular structure of the molecules constituting the raw materials onto the first surface of the wafer (200), while suppressing the chemical adsorption of at least a portion of the molecular structure of the molecules constituting the raw materials onto the second, third, and fourth surfaces of the wafer (200). As a result, a first layer is selectively (preferably) formed on the first surface. The first layer comprises at least a portion of the molecular structure of the molecules constituting the raw materials, which is a residue of the raw materials. That is, the first layer comprises at least a portion of the atoms constituting the raw materials.

[0165] In this step, by supplying the catalyst together with the raw material, the above-described reaction can be carried out under a non-plasma atmosphere and under low temperature conditions as described below. In this way, by forming the first layer under a non-plasma atmosphere and under low temperature conditions as described below, it becomes possible to suppress the removal and / or nullification of the inhibitor layer formed on the second surface, third surface, and fourth surface of the wafer (200). Furthermore, nullification of the inhibitor layer means that the molecular structure or atomic arrangement structure of the molecules constituting the inhibitor layer changes, thereby enabling the adsorption of the film-forming agent on the second surface, third surface, and fourth surface of the wafer (200), or the reaction of the film-forming agent with the second surface, third surface, and fourth surface.

[0166] In addition, by forming the first layer under a non-plasma atmosphere and under low temperature conditions as described below, it is possible to prevent the raw material from undergoing thermal decomposition (gas decomposition), i.e., self-decomposition, within the processing chamber (201). By doing so, it is possible to suppress the multiple deposition of at least a portion of the molecular structure of the molecules constituting the raw material on the first surface, second surface, third surface, and fourth surface of the wafer (200), and to selectively adsorb the raw material to the first surface among the first surface, second surface, third surface, and fourth surface of the wafer (200).

[0167] As for the processing conditions when supplying raw materials and catalysts in Step D1,

[0168] Treatment temperature: Room temperature (25℃) to 200℃, preferably room temperature to 150℃

[0169] Processing pressure: 133 to 1333 Pa

[0170] Processing time: 1 to 120 seconds, preferably 1 to 60 seconds

[0171] Raw material supply flow rate: 0.001 to 2 slm

[0172] Catalyst feed flow rate: 0.001 to 2 slm

[0173] Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm

[0174] This is an example.

[0175] After selectively forming a first layer on the first surface of the wafer (200), the valves (243b, 243d) are closed to stop the supply of raw materials and catalysts into the processing chamber (201), respectively. Then, gaseous substances remaining in the processing chamber (201) are removed from the processing chamber (201) by the same processing procedure and processing conditions as the purging in Step F (purging). In addition, it is preferable that the processing temperature when performing purging be the same as the processing temperature when supplying raw materials and catalysts.

[0176] In addition, in this step, when forming the first layer, at least a portion of the molecular structure of the molecules constituting the raw material may be adsorbed on the second surface, third surface, and a portion of the fourth surface of the wafer (200), but the amount of adsorption is extremely small, and the amount of adsorption on the first surface of the wafer (200) becomes overwhelmingly larger. This selective (preferential) adsorption is possible because the processing conditions in this step are low temperature conditions as described above, and conditions under which the raw material does not undergo gaseous decomposition within the processing chamber (201). Furthermore, while a high-density inhibitor layer is formed over the entire second surface, third surface, and fourth surface of the wafer (200), an inhibitor layer is not formed over a large area of ​​the first surface of the wafer (200).

[0177] As a raw material, for example, a halosilane gas, that is, a gas containing Si and halogen (a material containing Si and halogen), may be used. Halogens include chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc. It is preferable that the gas containing Si and halogen contains the halogen in the form of a chemical bond between Si and the halogen. As the gas containing Si and halogen, for example, a silane gas having a Si-Cl bond, that is, a chlorosilane gas, may be used. The gas containing Si and halogen may also contain C, and in that case, it is preferable that C be contained in the form of a Si-C bond. As the gas containing Si and halogen, for example, a silane gas containing Si, Cl, and an alkylene group and having a Si-C bond, that is, an alkylenechlorosilane gas, may be used. The alkylene group includes methylene groups, ethylene groups, propylene groups, butylene groups, etc. In addition, as a Si and halogen-containing gas, for example, a silane-based gas containing Si, Cl, and an alkyl group and having a Si-C bond, i.e., an alkylchlorosilane-based gas, may be used. The alkyl group includes a methyl group, an ethyl group, a propyl group, a butyl group, etc. The Si and halogen-containing gas may also contain O, and in that case, it is preferable to include O in the form of a Si-O bond, for example, in the form of a siloxane bond (Si-O-Si bond). As a Si and halogen-containing gas, for example, a silane-based gas containing Si, Cl, and a siloxane bond, i.e., a chlorosiloxane-based gas, may be used. It is preferable that all of these gases include Cl in the form of a Si-Cl bond. In addition to these, as a raw material, an amino group-containing gas (an amino group-containing material), such as an aminosilane-based gas, may also be used.

[0178] As raw materials, for example, 1,1,3,3-tetrachloro-1,3-disilacyclobutane (C2H4Cl4Si2), 1,1,2,2-tetrachloro-1,2-dimethyldisilane ((CH3)2Si2Cl4), 1,2-dichloro-1,1,2,2-tetramethyldisilane ((CH3)4Si2Cl2), bis(trichlorosilyl)methane ((SiCl3)2CH2), 1,2-bis(trichlorosilyl)ethane ((SiCl3)2C2H4), etc. may be used. In addition, tetrachlorosilane (SiCl4), hexachlorodisilane (Si2Cl6), octachlorotrisilane (Si3Cl8), etc. may also be used as raw materials. In addition, as raw materials, for example, hexachlorodisiloxane (Cl3Si-O-SiCl3), octachlorotrisiloxane (Cl3Si-O-SiCl2-O-SiCl3), etc. may be used. In addition, as raw materials, for example, tetrakis(dimethylamino)silane (Si[N(CH3)2]4), tris(dimethylamino)silane (Si[N(CH3)2]3H), bis(diethylamino)silane (Si[N(C2H5)2]2H2), bis(tert-butylamino)silane (SiH2[NH(C4H9)]2), (diisopropylamino)silane (SiH3[N(C3H7)2]), etc. may be used. As raw materials, one or more of these may be used.

[0179] As a catalyst, for example, an amine-based gas (amine-based substance) containing carbon (C), nitrogen (N), and hydrogen (H) can be used. As an amine-based gas (amine-based substance), a chain-based amine-based gas (chain-based amine-based substance) or a cyclic amine-based gas (cyclic amine-based substance) can be used. As a catalyst, for example, chain-based amines such as triethylamine ((C2H5)3N), diethylamine ((C2H5)2NH), monoethylamine ((C2H5)NH2), trimethylamine ((CH3)3N), dimethylamine ((CH3)2NH), and monomethylamine ((CH3)NH2) can be used. In addition, as a catalyst, for example, aminopyridine (C5H6N2), pyridine (C5H5N), picoline (C6H7N), rutidine (C7H9N), pyrimidine (C4H4N2), quinoline (C9H7N), piperazine (C4H10 N2), piperidine (C5H 11 Cyclic amines such as N), aniline (C6H7N), etc., can be used. As a catalyst, one or more of these can be used. This is also true for the reaction supply step described later.

[0180] [Step D2: Formation of the 2nd layer]

[0181] In Step D2, a reactant (reaction gas) and a catalyst (catalyst gas) are supplied as film-forming agents to the wafer (200) after Step D1 is performed, that is, the wafer (200) after the first layer has been formed on the first surface. Here, an example is described in which an oxidizing agent (oxidizing gas) is used as the reactant (reaction gas).

[0182] Specifically, valves (243c, 243d) are opened to flow the reactant and catalyst, respectively, into the gas supply pipes (232c, 232d). The reactant and catalyst, respectively, have their flow rates controlled by MFCs (241c, 241d) and are supplied into the processing chamber (201) through nozzles (249c, 249a), mixed within the processing chamber (201), and exhausted from the exhaust port (231a). At this time, the reactant and catalyst are supplied to the wafer (200) from the side of the wafer (200) (reactant + catalyst supply). At this time, valves (243f to 243h) may be opened to supply an inert gas into the processing chamber (201) through nozzles (249a to 249c), respectively.

[0183] By supplying a reactant and a catalyst to the wafer (200) under the processing conditions described below, it becomes possible to oxidize at least a portion of the first layer formed on the first surface of the wafer (200) in step D1. As a result, a second layer formed by the oxidation of the first layer is formed on the first surface.

[0184] In this step, by supplying a catalyst together with the reactant, it becomes possible to carry out the above-described reaction in a non-plasma atmosphere and under low temperature conditions as described below. In this way, by forming the second layer on the first surface in a non-plasma atmosphere and under low temperature conditions as described below, it becomes possible to suppress the removal and / or nullification of the inhibitor layer formed on the second, third, and fourth surfaces of the wafer (200).

[0185] As for the treatment conditions when supplying the reactant and catalyst in Step D2,

[0186] Treatment temperature: Room temperature (25℃) to 200℃, preferably room temperature to 150℃

[0187] Processing pressure: 133 to 1333 Pa

[0188] Processing time: 1 to 120 seconds, preferably 1 to 60 seconds

[0189] Reactor feed flow rate: 0.001 to 2 slm

[0190] Catalyst feed flow rate: 0.001 to 2 slm

[0191] Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm

[0192] This is an example.

[0193] After oxidizing the first layer formed on the first surface of the wafer (200) to change (convert) it into a second layer, the valves (243c, 243d) are closed to stop the supply of the reactant and catalyst into the processing chamber (201), respectively. Then, by the same processing procedure and processing conditions as the purging in Step F, the gaseous substances remaining in the processing chamber (201) are removed from the processing chamber (201) (purging). In addition, it is preferable that the processing temperature when performing purging be the same as the processing temperature when supplying the reactant and catalyst.

[0194] As the reactant, an oxidizing agent similar to the various oxidizing agents exemplified in Step A1 described above may be used. As the catalyst, a catalyst similar to the various catalysts exemplified in Step D1 described above may be used.

[0195] [Perform a prescribed number of times]

[0196] By performing a cycle in which the steps D1 and D2 described above are performed asynchronously, that is, alternately without synchronization, a predetermined number of times (n times, where n is an integer of 1 or 2 or more), a film can be selectively (preferably) grown on the first surface among the first surface, second surface, third surface, and fourth surface of the wafer (200), as shown in FIG. 5 (c), and the concave area can be filled with the film. That is, the film can be grown starting from the bottom surface of the concave area, which is the first surface of the wafer (200), and the film can be grown bottom-up within the concave area to fill the concave area with the film. For example, when using the raw materials, reactants, and catalysts described above, a SiOC film or a SiO film can be selectively grown as a film on the first surface, and the concave area can be filled with a SiOC film or a SiO film. It is preferable to repeat the cycle described above multiple times. That is, it is preferable to repeat the above-described cycle multiple times, making the thickness of the second layer formed per cycle thinner than the desired film thickness, until the film thickness formed by stacking the second layer reaches the desired film thickness.

[0197] In addition, by performing the aforementioned cycle a predetermined number of times, a film can be grown starting from the bottom surface (first surface) of the concave portion on the surface of the wafer (200) toward the opening side of the concave portion. At this time, since a high-density inhibitor layer is formed on the second surface constituting the upper and side surfaces of the concave portion, the growth of the film starting from the second surface can be suppressed. Furthermore, since a high-density inhibitor layer is formed on the third and fourth surfaces, which are surfaces different from the concave portion on the surface of the wafer (200), the growth of the film starting from the third and fourth surfaces can also be suppressed. That is, by performing the aforementioned cycle a predetermined number of times, the growth of the film starting from the bottom surface of the concave portion can be promoted while suppressing the growth of the film starting from the upper surface, side surfaces, and surfaces different from the concave portion. As a result, by growing a film bottom-up within the concave area, it becomes possible to fill the concave area with the film, as shown in Fig. 5 (c).

[0198] Additionally, when performing steps D1 and D2, as shown in Fig. 5(c), the inhibitor layer formed on the second surface, third surface, and fourth surface of the wafer (200) is maintained on the second surface, third surface, and fourth surface as described above, thereby suppressing the growth of the film starting from the second surface, third surface, and fourth surface. However, in cases where the formation of the inhibitor layer on the second surface, third surface, and fourth surface is insufficient due to some factor, the growth of the film starting from the second surface, third surface, and fourth surface may occur very slightly. However, even in this case, the thickness of the film formed starting from the second surface, third surface, and fourth surface becomes much thinner than the thickness of the film formed starting from the first surface. Therefore, even in that case, the filling within the concave portion by the bottom-up growth described above can be properly performed.

[0199] (Step E: PT)

[0200] After Step D is completed, Step E is performed. In Step E, a post-treatment (PT) is performed on the film formed to fill the concave area by performing heat treatment (annealing treatment) on the wafer (200). At this time, the output of the heater (207) is adjusted so that the temperature inside the processing room (201), that is, the temperature of the wafer (200) after the film formed to fill the concave area is higher than the temperature of the wafer (200) in Steps A, B, C, and D, preferably higher than the temperature of the wafer (200) in these steps.

[0201] By performing PT on the wafer (200), impurities included in the film formed to fill the concave portion can be removed or defects can be repaired, thereby hardening the film. By hardening the film, the processing resistance of the film, that is, etching resistance, can be improved.

[0202] In addition, by performing PT on the wafer (200), as shown in FIG. 5 (d), the inhibitor layer on the second surface, third surface, and fourth surface of the wafer (200), i.e., the interface between the side of the concave portion and the film (SiOC), the other side of the concave portion, the upper surface of the concave portion, or the surface of a part different from the concave portion can be removed and / or neutralized.

[0203] In addition, this step may be performed with an inert gas supplied into the processing chamber (201), or with a reactive substance such as an oxidizing agent (oxidizing gas). When a reactive substance such as an oxidizing agent is supplied, it becomes possible to effectively remove impurities contained in the film formed to fill the concave area, repair defects, or harden the film. In addition, it becomes possible to enhance the effect of removing and / or neutralizing the inhibitor layer at the interface between the side of the concave area and the film, at another side of the concave area, at the top surface of the concave area, or on a surface different from the concave area. In this case, the reactive substance such as the inert gas or oxidizing agent (oxidizing gas) is also referred to as an assist material. In addition, the assist material may be supplied by exciting it into a plasma state, and the above-mentioned effect can be further enhanced.

[0204] As for the processing conditions when performing PT in Step E,

[0205] Processing temperature: 200 to 1000℃, preferably 400 to 700℃

[0206] Processing pressure: 1 to 120,000 Pa

[0207] Processing time: 1 to 18,000 seconds

[0208] Assist material supply flow rate: 0 to 50 slm

[0209] RF Power: 0 to 10,000W

[0210] is exemplified.

[0211] Additionally, regarding the film formed to fill the concave area, if there is no need to remove impurities, repair defects, or harden it, or if there is no need to remove and / or neutralize the inhibitor layer, Step E may be omitted.

[0212] (After purge and return to atmospheric pressure)

[0213] After Step E is completed (or after Step D is completed if Step E is omitted), an inert gas as a purge gas is supplied into the treatment chamber (201) from each of the nozzles (249a to 249c) and exhausted from the exhaust port (231a). As a result, the treatment chamber (201) is purged, and any remaining gas or reaction byproducts within the treatment chamber (201) are removed from the treatment chamber (201) (after-purge). Afterward, the atmosphere within the treatment chamber (201) is replaced with an inert gas (inert gas replacement), and the pressure within the treatment chamber (201) is returned to normal pressure (atmospheric pressure return).

[0214] (Boat Unload and Wafer Discharge)

[0215] After that, the seal cap (219) is lowered by the boat elevator (115), and the bottom of the manifold (209) is opened. Then, the finished wafer (200) is discharged (boat unloaded) from the bottom of the manifold (209) to the outside of the reaction tube (203) while supported by the boat (217). After boat unloading, the shutter (219s) is moved, and the bottom opening of the manifold (209) is sealed by the shutter (219s) via the O-ring (220c) (shutter close). After the finished wafer (200) is discharged to the outside of the reaction tube (203), it is ejected from the boat (217) (wafer discharge).

[0216] (3) Effects of this embodiment

[0217] According to the present embodiment, one or more effects as described below are obtained.

[0218] (a) By performing Step A, which includes Step A1, in which an oxidizing agent and a reducing agent are excited and supplied to the wafer (200) in a plasma state, and Step A2, in which a reducing agent is excited and supplied to the wafer (200) in a plasma state, and Step B, which involves heat-treating the wafer (200) after Step A is performed, the second surface of the wafer (200) can be made to have a high density of OH terminals, and the first surface of the wafer (200) can be made to have no OH terminals, or have a much smaller amount of OH terminals than the amount of OH terminals on the second surface of the wafer (200). That is, the amount (density, concentration) of OH terminals on the second surface of the wafer (200) can be made to be greater (higher) than the amount (density, concentration) of OH terminals on the first surface of the wafer (200). Additionally, the amount (density, concentration) of OH terminals on the first surface of the wafer (200) may be reduced to zero. By doing so, in Step C, at least a portion of the molecular structure of the molecule constituting the modifier is adsorbed at a high density on the second surface of the wafer (200) selectively (preferably), thereby making it possible to form a high-density inhibitor layer on the second surface selectively (preferably). Furthermore, in Step D, it becomes possible to selectively (preferably) grow a film on the first surface of the wafer (200) with high precision while suppressing the growth of the film on the second surface of the wafer (200). As a result, it becomes possible to fill the concave area with a film with high selectivity while suppressing the growth of the film on the second surface of the wafer (200).

[0219] (b) By performing Step A, which includes Step A1, in which an oxidizing agent and a reducing agent are excited and supplied to the wafer (200) in a plasma state, and Step A2, in which a reducing agent is excited and supplied to the wafer (200) in a plasma state, and Step B, in which the wafer (200) is heat-treated after Step A is performed, the second surface of the wafer (200) and other surfaces (third surface or fourth surface) each have a high density of OH terminals, and the first surface of the wafer (200) does not have OH terminals, or has a much smaller amount of OH terminals than the amount of OH terminals on the second surface and other surfaces (third surface or fourth surface). That is, the amount (density, concentration) of OH terminals at each of the second surface and other surfaces (third surface or fourth surface) of the wafer (200) can be made greater (higher) than the amount (density, concentration) of OH terminals at the first surface of the wafer (200). Additionally, the amount (density, concentration) of OH terminals at the first surface of the wafer (200) can be made zero. By doing so, in step C, at least a portion of the molecular structure of the molecule constituting the modifier is adsorbed at a high density on the second surface and other surfaces (third surface or fourth surface) of the wafer (200) selectively (preferably), thereby making it possible to form a high-density inhibitor layer on the second surface and other surfaces (third surface or fourth surface) selectively (preferably). Additionally, in step D, it becomes possible to selectively (preferentially) grow a film on the first surface of the wafer (200) with high precision while suppressing the growth of the film on the second surface and other surfaces (third or fourth surfaces) of the wafer (200). As a result, it becomes possible to fill the concave area with a film with high selectivity while suppressing the growth of the film on the second surface and other surfaces (third or fourth surfaces) of the wafer (200).

[0220] (c) By selectively forming a high-density inhibitor layer on the second surface constituting the upper and side surfaces of the concave portion of the wafer (200), the growth of the film originating from the upper and side surfaces of the concave portion can be suppressed, while the growth of the film originating from the bottom surface of the concave portion can be promoted. As a result, the film can be grown from the bottom side of the concave portion toward the opening side of the concave portion, thereby allowing the film to be grown bottom-up within the concave portion. Consequently, it becomes possible to fill the concave portion with the film without creating voids or seams within the film. That is, it becomes possible to form a void-free and seamless film within the concave portion, thereby improving the filling characteristics.

[0221] (d) By selectively forming a high-density inhibitor layer on a surface other than the second surface (third surface or fourth surface) that constitutes the upper surface and side surface of the concave portion of the wafer (200), the growth of the film originating from the upper surface and side surface and the other surface (third surface or fourth surface) of the concave portion can be suppressed, while the growth of the film originating from the bottom surface of the concave portion can be promoted. As a result, the concave portion can be filled with a film without growing a film on the upper surface (second surface) and the other surface (third surface or fourth surface) of the concave portion. As a result, as shown in (c) of FIG. 5, at the time when the film formation process is finished, a state can be created in which no film (SiOC) is formed on the upper surface or the other surface (third surface or fourth surface) of the concave portion. In addition, as shown in FIG. 5(c), at the time when the film deposition process is finished, the concave portion in the sidewall of the stacked structure formed by alternately stacking the first material (SiGe) and the second material (Si) on the surface of the wafer (200) can be filled with a film (SiOC) to flatten the sidewall. By doing so, it becomes possible to omit the process of removing the excess film formed on the upper surface (second surface) or other surfaces (third surface or fourth surface), etc., of the concave portion after the film deposition process, which was conventionally required, by etching.

[0222] In addition, as described above, even though inhibitor layers are formed on the second surface, the third surface, and the fourth surface, there may be cases where the growth of the film originating from the second surface, the third surface, and the fourth surface occurs extremely slightly due to some factor. In this case, a process to etch the excess film formed on the upper surface of the concave part (the second surface) or other surfaces (the third surface or the fourth surface) may be required. However, even in such cases, the excess film formed on the upper surface of the concave part or other surfaces (the third surface or the fourth surface) is extremely small as described above, so the load in the process of etching the excess film is significantly reduced, and the time required for etching can be significantly shortened.

[0223] Meanwhile, when the concave area is filled with a film by a conventional film formation method that performs only Step D, as shown in FIG. 6(b), a film (SiOC) is formed on the entire sidewall of a stacked structure formed by alternately stacking a first material (SiGe) and a second material (Si) on the surface of the wafer (200). A film (SiOC) is also formed on other surfaces (third surface or fourth surface), etc. At that time, as shown in FIG. 6(b), voids or seams may be formed in the film due to the shape of the concave area. In this case, in order to flatten the sidewall by filling the concave area on the sidewall of the stacked structure formed by alternately stacking the first material and the second material with a film, it is necessary to perform a process of etching the excess film formed on the upper surface of the concave area. In addition, it may be necessary to etch the film formed on other surfaces (third surface or fourth surface), etc. For example, regarding a substrate having the configuration of FIG. 6(b) on its surface, if a process is performed to etch the excess film formed on the upper surface of the concave portion or another surface (hereinafter, the upper surface of the concave portion, etc.), a state in which no film is formed on the upper surface of the concave portion, etc., can be produced as shown in FIG. 6(c). However, in this case, as shown in FIG. 6(c), voids or seams formed in the film during film formation are retained, and in some cases, the voids or seams become deeper due to etching, or the sidewalls of a stacked structure formed by alternately stacking a first material and a second material cannot be flattened. Furthermore, when using a conventional film formation method, it becomes essential to perform a process to etch the excess film, which prolongs the overall processing time and reduces productivity.

[0224] In contrast, according to the present embodiment, as illustrated in FIG. 5 (c), it is possible to form a void-free and seamless film within a concave area while suppressing the growth of the film on the upper surface of the concave area, and at the time the film deposition process is completed, the concave area within the sidewall of a stacked structure formed by alternately stacking a first material (SiGe) and a second material (Si) can be filled with a film (SiOC), thereby making the sidewall flat. In addition, the growth of the film on other surfaces (third surface or fourth surface), etc., can also be suppressed. As a result, it becomes possible to omit the process of removing the excess film formed on the upper surface of the concave area, etc., by etching after the film deposition process, which was essential in conventional film deposition methods. For example, even if an inhibitor layer is formed on the upper surface of a concave area, etc., and even if film growth originating from the upper surface of a concave area occurs very slightly due to some factor, the excess film formed on the upper surface of a concave area, etc. is very small, so the load in the process of etching the excess film is significantly reduced, and it is possible to significantly shorten the time required for etching. In other words, according to the present embodiment, void-free and seamless filling is possible, and not only is it possible to improve filling characteristics, but the overall processing time can be significantly shortened by omitting the process of etching the excess film or reducing the load in the process of etching the excess film, and thus it is possible to significantly improve productivity.

[0225] (e) By making the processing temperature in Step B higher than the processing temperature in Step A, it becomes possible to selectively sublimate and remove the oxide formed on the first surface of the wafer (200) while retaining (maintaining) the OH terminals on the second, third, and fourth surfaces of the wafer (200), thereby effectively removing the OH terminals on the first surface. Additionally, by making the processing temperature in Step B higher than the processing temperature in Step A, it becomes possible to perform these actions more effectively. At this time, it is preferable to make the processing temperature in Step B higher than the respective processing temperatures in Step A and Step C. At this time, it is more preferable to make the processing temperature in Step B higher than the respective processing temperatures in Step A and Step C. At this time, it is preferable to make the processing temperature in Step B higher than the respective processing temperatures in Step A, Step C, and Step D. At this time, it is more preferable to make the processing temperature in Step B higher than the respective processing temperatures in Step A, Step C, and Step D.

[0226] By doing so, it becomes possible to effectively make the amount (density, concentration) of OH terminals on each of the second, third, and fourth surfaces of the wafer (200) before performing Step C greater (higher) than the amount (density, concentration) of OH terminals on the first surface of the wafer (200). Additionally, the amount (density, concentration) of OH terminals on the first surface of the wafer (200) can be made zero. By doing so, in Step C, it becomes possible to effectively form a high-density inhibitor layer on the second, third, and fourth surfaces of the wafer (200) by selectively (preferably) adsorbing at least a portion of the molecular structure of the molecule constituting the modifier at a high density. As a result, it becomes possible to fill the concave area with a film with high selectivity while suppressing the growth of the film on the second, third, and fourth surfaces of the wafer (200). Additionally, in step B, by simply adjusting the temperature of the wafer (200), that is, by simply heating the wafer (200) to a predetermined temperature, the oxide formed on the first surface of the wafer (200) can be selectively sublimated and removed while retaining (maintaining) the OH terminals on each of the second surface, third surface, and fourth surface of the wafer (200), thereby selectively removing the OH terminals on the first surface.

[0227] (f) Before performing Step A, by performing Step F, which removes the natural oxide film on the surface of the wafer (200), the natural oxide film formed unevenly on the first surface, second surface, third surface, etc. of the wafer (200) can be removed, and the OH terminals formed unevenly on these surfaces can be removed. Then, by performing Step A, the first surface, second surface, third surface, etc. of the wafer (200) can be oxidized uniformly, and a very thin and very uniform oxide film can be formed on these surfaces. As a result, OH terminals can be formed uniformly on these surfaces. In addition, if the fourth surface is composed of an SiO film, the OH terminals are formed uniformly on the fourth surface as well. After that, by performing Step B, the oxide film uniformly formed on the first surface of the wafer (200) can be selectively sublimated and removed while retaining (maintaining) the OH terminals uniformly formed on the second, third, and fourth surfaces of the wafer (200), thereby allowing the OH terminals on the first surface to be selectively removed. As a result, in Step C, at least a portion of the molecular structure of the molecule constituting the modifier can be more uniformly adsorbed on the second, third, and fourth surfaces, making it possible to form the inhibitor layer more uniformly. Additionally, in Step D, it becomes possible to form a film uniformly on the first surface.

[0228] (g) After Step D is completed, heat treatment (PT) can be performed on the film formed to fill the concave area to remove impurities contained in the film formed to fill the concave area, repair defects, or harden the film. Additionally, the inhibitor layer on the second surface, third surface, and fourth surface of the wafer (200)—that is, the interface between the side of the concave area and the film, the other side of the concave area, the top surface of the concave area, or the surface of a part different from the concave area—can be removed and / or neutralized. At this time, these effects can be enhanced by making the temperature of the wafer (200) higher than the temperature of the wafer (200) in Steps A to D. Additionally, these effects can be further enhanced by making the temperature of the wafer (200) higher than the temperature of the wafer (200) in Steps A to D. Additionally, at this time, a reactive material such as an inert gas or an oxidizing agent (oxidizing gas), i.e., an assist material, may be supplied into the processing chamber (201). By supplying an assist material during heat treatment, it becomes possible to enhance the aforementioned effect. Additionally, at this time, the assist material may be supplied after being excited into a plasma state. By doing so, it becomes possible to further enhance the aforementioned effect.

[0229] (h) The first surface of the wafer (200) is formed by a film containing a first element, and the second surface is formed by a film containing a second element, thereby significantly obtaining the above-described effect. Additionally, the first element includes a Group 14 element, and the second element includes a Group 14 element. The first surface of the wafer (200) is formed by a Ge-containing film, and the second surface is formed by a Si-containing film, thereby significantly obtaining the above-described effect. The first surface of the wafer (200) is formed by a Si and Ge-containing film, and the second surface is formed by a Si-containing film, thereby significantly obtaining the above-described effect.

[0230] (i) The first surface of the wafer (200) is formed by a film containing a first element, the second surface is formed by a film containing a second element, the third surface is formed by a film containing a third element, and the fourth surface is formed by a film containing a fourth element, thereby significantly obtaining the above-described effect. In addition, the first element contains a group 14 element, the second element contains a group 14 element, the third element contains a group 15 element, and the fourth element contains a group 16 element. The first surface of the wafer (200) is formed by a Ge-containing film, the second surface is formed by a Si-containing film, the third surface is formed by an N-containing film, and the fourth surface is formed by an O-containing film, thereby more significantly obtaining the above-described effect. The first surface of the wafer (200) is composed of a Si and Ge-containing film, the second surface is composed of a Si-containing film, the third surface is composed of a Si and N-containing film, and the fourth surface is composed of a Si and O-containing film, thereby making the above-described effect more pronounced.

[0231] (4) Variant example

[0232] The substrate processing sequence in the present embodiment may be modified as shown in the variations below. These variations may be combined arbitrarily. Unless otherwise specifically stated, the processing procedure and processing conditions at each step of each variation may be the same as the processing procedure and processing conditions at each step of the substrate processing sequence described above.

[0233] (Variation Example 1)

[0234] As shown in the processing sequence below, in Step A, after performing Step A1 and Step A2, Step A3 may also be performed to supply an oxidizing agent and a reducing agent to the wafer (200) after Step A1 and Step A2 have been performed by exciting them into a plasma state. In this case, Step A further includes Step A3. That is, Step A includes Step A1, Step A2, and Step A3. The processing procedure and processing conditions in Step A3 may be the same as, for example, the processing procedure and processing conditions in Step A1 described above.

[0235] Oxidizing agent * +Reducing agent * → Reducing agent * → Oxidizing agent * +Reducing agent * → Heat treatment → Modifier → (Raw material → Reactant) × n

[0236] Oxidizing agent * +Reducing agent * → Reducing agent * → Oxidizing agent * +Reducing agent * → Heat treatment → Modifier → (Raw material + Catalyst → Reactant) × n

[0237] Oxidizing agent * +Reducing agent * → Reducing agent * → Oxidizing agent * +Reducing agent * → Heat treatment → Modifier → (Raw material → Reactant + Catalyst) × n

[0238] Oxidizing agent * +Reducing agent * → Reducing agent * → Oxidizing agent * +Reducing agent * → Heat treatment → Modifier → (Raw material + Catalyst → Reactant + Catalyst) × n

[0239] In this modified example, the same effect as in the above-described embodiment is obtained. Furthermore, according to this modified example, by adding Step A3 in Step A, the density of OH terminals on the first surface, second surface, third surface, and fourth surface of the wafer (200) can be increased, making it possible to create a state in which each surface has a higher density of OH terminals. By doing so, the density of the inhibitor layer formed on the second surface, third surface, and fourth surface of the wafer (200) in Step C can be increased, making it possible to increase the film formation inhibition effect (adsorption inhibition effect, reaction inhibition effect) by the inhibitor layer.

[0240] (Variation Example 2)

[0241] Depending on the surface condition of the wafer (200), step F (removal of natural oxide film) may be omitted. For example, after forming a stacked structure on the surface of the wafer (200) having a first surface (surface of SiGe film), a second surface (surface of Si film), a third surface (surface of SiN film), and a fourth surface (surface of SiO film) as shown in FIG. 5 (a), there may be cases where the surface of the wafer (200) is not exposed to the atmosphere, or where the amount of exposure to the atmosphere is small, or where the exposure time to the atmosphere is short, and each surface is in an appropriate surface condition. In such cases, step F can be omitted, and the processing sequence can be started from step A. In this modified example, the same effect as in the above-described embodiment is obtained. Furthermore, by omitting step F, the overall processing time can be shortened, and it is possible to improve productivity.

[0242] (Variation Example 3)

[0243] Step E may be omitted if there is no need to remove impurities, repair defects, or harden the film formed to fill the concave area, or if there is no need to remove and / or neutralize the inhibitor layer on each surface of the wafer (200). For example, if the amount of impurities or defects contained in the film formed to fill the concave area is within an acceptable range, Step E may be omitted. Additionally, Step E may be omitted if the amount of inhibitor layer residues or other residues on the interface between the side of the concave area and the film, the other side of the concave area, the top surface of the concave area, or a surface different from the concave area is within an acceptable range. Furthermore, if the inhibitor layer residues or other residues on the interface between the side of the concave area and the film, the other side of the concave area, the top surface of the concave area, or a surface different from the concave area are removed by a reaction during the film formation process or post-film formation process, Step E may be omitted. In this modified example, the same effect as in the above-described embodiment is obtained. Furthermore, by omitting Step E, the overall processing time can be shortened, making it possible to improve productivity.

[0244] <Other Aspects of the Present Disclosure>

[0245] The embodiments of the present disclosure have been described in detail above. However, the present disclosure is not limited to the embodiments described above and can be modified in various ways without departing from the essence thereof.

[0246] In addition, for example, in step F, an etching agent may be supplied to the wafer (200) by plasma-exciting it. This allows the etching rate to be increased when etching the natural oxide film. Also, in step B, an inert gas may be supplied by plasma-exciting it. This makes it possible to remove oxides such as GeO formed on the first surface by sublimation, and simultaneously perform plasma treatment on the first surface after the oxides have been removed. In addition, in step E, an inert gas or an assist material may be supplied by plasma-exciting it. This makes it possible to more effectively remove impurities contained in the film formed to fill the concave area, repair defects, or harden the film. Furthermore, it makes it possible to further enhance the effect of removing and / or neutralizing the inhibitor layer at the interface between the side of the concave area and the film, the other side of the concave area, the top surface of the concave area, or the surface of a part different from the concave area.

[0247] In addition, for example, in Step D, not only SiOC films or SiO films may be formed, but also silicon-based oxide films such as silicon oxycarbonitride (SiOCN), silicon oxynitride (SiON), silicon borate nitride (SiBON), and silicon borate carbonitride (SiBOCN). Furthermore, in Step D, metal-based oxide films such as aluminum oxide (AlO), titanium oxide (TiO), hafnium oxide (HfO), and zirconium oxide (ZrO) may be formed.

[0248] It is preferable that the recipes used for each process be prepared individually according to the processing content and stored by recording them in a storage device (121c) via an electrical communication line or an external storage device (123). Furthermore, when each process is initiated, it is preferable that the CPU (121a) appropriately selects a suitable recipe according to the processing content from among the multiple recipes recorded and stored in the storage device (121c). By doing so, it becomes possible to form films of various film types, composition ratios, film quality, and film thicknesses with good reproducibility in a single substrate processing device. In addition, the burden on the operator can be reduced, allowing each process to be initiated quickly while avoiding operational errors.

[0249] The above-described recipe is not limited to being newly created; for example, it may be prepared by modifying an existing recipe that is already installed in a substrate processing device. When modifying a recipe, the modified recipe may be installed in the substrate processing device via an electrical communication line or a recording medium on which the recipe is recorded. Alternatively, the existing recipe that is already installed in the substrate processing device may be modified directly by operating an input / output device (122) provided in the existing substrate processing device.

[0250] In the above-described embodiment, an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at once was described. The present disclosure is not limited to the above-described embodiment and can be suitably applied to cases where a film is formed using, for example, a single-wafer-type substrate processing apparatus that processes one or several substrates at once. In addition, in the above-described embodiment, an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace was described. The present disclosure is not limited to the above-described embodiment and can be suitably applied to cases where a film is formed using a substrate processing apparatus having a cold-wall type processing furnace.

[0251] In addition, in the above-described embodiment, an example was described in which Step F and Steps A through E are performed continuously within the same processing chamber (in-situ) of the same substrate processing device (substrate processing system), that is, in the same processing unit. The present disclosure is not limited to the above-described embodiment, and can be suitably applied in cases where each step is performed in a different processing chamber (ex-situ) of each of the different substrate processing devices (i.e., in a different processing unit), using a substrate processing system comprising a plurality of standalone substrate processing devices (a first substrate processing device, a second substrate processing device, and a third substrate processing device), as shown in FIG. 7, for example. In this case, Step F may be performed in the first substrate processing device, Step A in the second substrate processing device, and Steps B through E in the third substrate processing device. Furthermore, in cases where Step A can be omitted, Step A may be performed in the first substrate processing device, Steps B through D in the second substrate processing device, and Step E in the third substrate processing device. In addition, in cases where steps A and E can be omitted, for example, step A may be performed in the first substrate processing device, step B in the second substrate processing device, and steps C to D in the third substrate processing device. Also, in this case, for example, two substrate processing devices may be used, so that step A is performed in the first substrate processing device and steps B to D are performed in the second substrate processing device. In such cases, the first substrate processing device, the second substrate processing device, and the third substrate processing device are also referred to as the first processing unit, the second processing unit, and the third processing unit, respectively. Furthermore, the above-described embodiment may be an example in which the first processing unit, the second processing unit, and the third processing unit are the same processing unit.

[0252] In addition, as illustrated in FIG. 8, a substrate processing system comprising a cluster-type substrate processing device having a plurality of processing rooms (a first processing room, a second processing room, and a third processing room) arranged around a return room can be appropriately applied even when each step is performed in a different processing room of the same substrate processing device, that is, in a different processing unit. In this case, for example, step F can be performed in the first processing room, step A can be performed in the second processing room, and steps B to E can be performed in the third processing room. Also, if step A can be omitted, for example, step A can be performed in the first processing room, steps B to D can be performed in the second processing room, and step E can be performed in the third processing room. Also, if steps A and E can be omitted, for example, step A can be performed in the first processing room, step B can be performed in the second processing room, and steps C to D can be performed in the third processing room. In this case, for example, two processing rooms may be used, so that Step A is performed in the first processing room and Steps B through D are performed in the second processing room. In such a case, the first processing room, the second processing room, and the third processing room are also referred to as the first processing unit, the second processing unit, and the third processing unit, respectively. Furthermore, the above-described embodiment may be an example in which the first processing unit, the second processing unit, and the third processing unit are the same processing unit.

[0253] Even when using such a substrate processing system or substrate processing device, each processing can be performed under the same processing procedure and processing conditions as in the above-described embodiment, and the same effect as in the above-described embodiment is obtained.

[0254] The aforementioned embodiments may be used in appropriate combinations. The processing steps and processing conditions in this case may be similar to, for example, the processing steps and processing conditions of the aforementioned embodiments.

[0255] [Example]

[0256] Evaluation Sample 1 was fabricated by performing the processing sequence of the above-described embodiment on a wafer having a stacked structure formed by alternately stacking SiGe films and Si films on a surface as shown in FIG. 5(a), wherein SiO films, SiN films, and SiO films are stacked thereon, and on the sidewall of the stacked structure of SiGe films and Si films, a concave portion having a depth direction parallel to the wafer surface (transverse direction) in which the top and side surfaces are composed of Si films and the bottom surface is composed of SiGe films. Subsequently, a cross-sectional TEM image of Evaluation Sample 1 was taken. FIG. 9 shows the cross-sectional TEM image of Evaluation Sample 1.

[0257] Evaluation Sample 2 was fabricated by forming a SiOC film to fill the concave area on a wafer having the same configuration as the wafer used to fabricate Evaluation Sample 1, by performing the processing sequence of Modified Example 1 described above. Afterward, a cross-sectional TEM image of Evaluation Sample 2 was taken. Figure 10 shows a cross-sectional TEM image of Evaluation Sample 2.

[0258] As shown in FIGS. 9 and 10, it was confirmed that in either Evaluation Sample 1 or Evaluation Sample 2, the SiOC film was not formed on the upper surface of the concave portion (the surface of the Si film) or on other surfaces (the surface of the SiN film or SiO film), but was selectively formed only within the concave portion. In addition, in either Evaluation Sample 1 or Evaluation Sample 2, it was confirmed that the concave portion in the sidewall of a stacked structure formed by alternately stacking SiGe films and Si films could be filled with the SiOC film, thereby making the sidewall flat. Furthermore, in either Evaluation Sample 1 or Evaluation Sample 2, it was confirmed that no voids or seams were formed in the SiOC film that filled the concave portion. In addition, it was confirmed that in either evaluation sample 1 or evaluation sample 2, no plasma damage occurred to any of the SiGe film, Si film, SiN film, or SiO film on the surface of the wafer. Explanation of the symbols

[0259] 200: Wafer (substrate)

Claims

Claim 1 (a) (a1) a process of supplying an oxidizing agent and a reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state, (a2) a process of supplying a reducing agent to the substrate by exciting it into a plasma state, and (b) a process of heat-treating the substrate after (a) is performed, wherein the first surface is composed of a germanium-containing film and the second surface is composed of a silicon-containing film. Claim 2 (a) (a1) a process of supplying an oxidizing agent and a reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state, (a2) a process of supplying a reducing agent to the substrate by exciting it into a plasma state, (b) a process of heat-treating the substrate after (a) is performed, and (c) a process of forming an inhibitor layer on the second surface by supplying a modifying agent to the substrate after (b) is performed. Claim 3 A substrate treatment method according to paragraph 2, further comprising a process of forming a film on the first surface by supplying a film-forming agent to the substrate after (d) (c) is performed. Claim 4 (a) (a1) a process of supplying an oxidizing agent and a reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state, (a2) a process of supplying a reducing agent to the substrate by exciting them into a plasma state, (a3) ​​a process of supplying an oxidizing agent and a reducing agent to the substrate after (a1) and (a2) have been performed by exciting them into a plasma state, and (b) a process of heat-treating the substrate after (a) has been performed. Claim 5 A substrate processing method according to claim 1, wherein the processing temperature in (b) is greater than or equal to the processing temperature in (a). Claim 6 A substrate processing method according to paragraph 2, wherein the processing temperature in (b) is greater than or equal to the respective processing temperatures in (a) and (c). Claim 7 A substrate treatment method according to paragraph 3, wherein the treatment temperature in (b) is greater than or equal to the respective treatment temperatures in (a), (c), and (d). Claim 8 A substrate treatment method according to claim 1, wherein the treatment temperature in (b) is 100°C or higher and 400°C or lower. Claim 9 (a) (a1) a process of supplying an oxidizing agent and a reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state, (a2) a process of supplying a reducing agent to the substrate by exciting it into a plasma state, and (b) a process of heat-treating the substrate after (a) is performed, wherein in (a), OH terminals are formed on the first surface and the second surface, and in (b), OH terminals formed on the first surface are removed while retaining the OH terminals formed on the second surface. A substrate treatment method. Claim 10 (a) (a1) a process of supplying an oxidizing agent and a reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state, (a2) a process of supplying a reducing agent to the substrate by exciting it into a plasma state, and (b) a process of heat-treating the substrate after (a) is performed, wherein in (a), the first surface and the second surface are oxidized, and in (b), the oxide formed on the first surface is sublimated while leaving the oxide formed on the second surface. Claim 11 A substrate processing method according to claim 1, wherein the substrate further comprises at least one of a third surface and a fourth surface. Claim 12 A substrate processing method according to claim 9, wherein the substrate further comprises at least one of a third surface and a fourth surface, wherein (a) an OH terminal is formed on at least one of the third surface and the fourth surface, and (b) an OH terminal formed on the first surface is removed while leaving the OH terminal formed on at least one of the third surface and the fourth surface. Claim 13 A substrate treatment method according to claim 10, wherein the substrate further comprises at least one of a third surface and a fourth surface, wherein (a) at least one of the third surface and the fourth surface is oxidized, and (b) the oxide formed on the first surface is sublimated while leaving the oxide formed on at least one of the third surface and the fourth surface. Claim 14 In paragraph 2, the substrate further has at least one of a third surface and a fourth surface, and (c) a substrate processing method in which the inhibitor layer is formed on at least one of the second surface and the third surface and the fourth surface. Claim 15 In paragraph 3, the substrate further has at least one of a third surface and a fourth surface, and (c) a substrate processing method in which the inhibitor layer is formed on at least one of the second surface and the third surface and the fourth surface. Claim 16 delete Claim 17 A substrate treatment method according to claim 1, wherein the substrate further comprises at least one of a third surface and a fourth surface, wherein the third surface is formed by a nitrogen-containing film and the fourth surface is formed by an oxygen-containing film. Claim 18 (a) (a1) a process of supplying an oxidizing agent and a reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state, (a2) a process of supplying a reducing agent to the substrate by exciting it into a plasma state, and (b) a process of heat-treating the substrate after (a) is performed, wherein a concave portion is provided on the surface of the substrate, the first surface is the bottom surface of the concave portion, and the second surface is the side surface of the concave portion, or the side surface and top surface of the concave portion. A substrate processing method. Claim 19 A method for processing a substrate according to claim 18, wherein the substrate further comprises at least one of a third surface and a fourth surface, and the third surface and the fourth surface are surfaces of a portion different from the concave portion on the surface of the substrate. Claim 20 A method for manufacturing a semiconductor device having a process for performing a substrate processing method described in any one of claims 1, 2, 4, 9, 10 and 18. Claim 21 A substrate processing system for processing a substrate, comprising: an oxidizing agent supply system for supplying an oxidizing agent to a substrate; a reducing agent supply system for supplying a reducing agent to a substrate; a plasma excitation unit for exciting the oxidizing agent and the reducing agent into a plasma state; a heater for heating a substrate; and a control unit configured to control the oxidizing agent supply system, the reducing agent supply system, and the heater so as to perform the following processes: (a) a process of supplying the oxidizing agent and the reducing agent by exciting them into a plasma state to a substrate having a first surface formed by a germanium-containing film and a second surface formed by a silicon-containing film; (a2) a process of supplying the reducing agent by exciting it into a plasma state to the substrate; and (b) a process of heat treating the substrate after (a) has been performed. Claim 22 A program recorded on a computer-readable recording medium that executes a procedure for performing a substrate processing method described in any one of claims 1, 2, 4, 9, 10, and 18 on a substrate processing system by means of a computer. Claim 23 A substrate processing system for processing a substrate, comprising: an oxidizing agent supply system for supplying an oxidizing agent to a substrate; a reducing agent supply system for supplying a reducing agent to a substrate; a modifying agent supply system for supplying a modifying agent to a substrate; a plasma excitation unit for exciting the oxidizing agent and the reducing agent into a plasma state; a heater for heating a substrate; and a control unit configured to control the oxidizing agent supply system, the reducing agent supply system, the modifying agent supply system and the heater so as to perform the following processes: (a) (a1) a process of supplying the oxidizing agent and the reducing agent to a plasma state by exciting them to a first surface and a second surface; (a2) a process of supplying the reducing agent to a plasma state by exciting it to a substrate; (b) a process of heat-treating the substrate after (a) is performed; and (c) a process of forming an inhibitor layer that inhibits the adsorption of a film-forming agent on the second surface by supplying the modifying agent to the substrate after (b). Claim 24 A substrate processing system for processing a substrate, comprising: an oxidizing agent supply system for supplying an oxidizing agent to a substrate; a reducing agent supply system for supplying a reducing agent to a substrate; a plasma excitation unit for exciting the oxidizing agent and the reducing agent into a plasma state; a heater for heating a substrate; and a control unit configured to control the oxidizing agent supply system, the reducing agent supply system, and the heater so as to perform the following processes: (a) (a1) a process of supplying the oxidizing agent and the reducing agent to a plasma state by exciting them to a substrate having a first surface and a second surface; (a2) a process of supplying the reducing agent to a plasma state by exciting it to a substrate; (a3) ​​a process of supplying the oxidizing agent and the reducing agent to a plasma state by exciting them to a substrate after (a1) and (a2); and (b) a process of heat treating the substrate after (a). Claim 25 A substrate processing system for processing a substrate, comprising: an oxidizing agent supply system for supplying an oxidizing agent to a substrate; a reducing agent supply system for supplying a reducing agent to a substrate; a plasma excitation unit for exciting the oxidizing agent and the reducing agent into a plasma state; a heater for heating a substrate; and a control unit configured to control the oxidizing agent supply system, the reducing agent supply system, and the heater, such that (a) (a1) a process of supplying the oxidizing agent and the reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state; (a2) a process of supplying the reducing agent to a substrate by exciting it into a plasma state; and (b) a process of heat-treating the substrate after (a) is performed, wherein in (a), OH terminals are formed on the first surface and the second surface, and in (b), the OH terminals formed on the first surface are removed while the OH terminals formed on the second surface remain. Claim 26 A substrate processing system for processing a substrate, comprising: an oxidizing agent supply system for supplying an oxidizing agent to a substrate; a reducing agent supply system for supplying a reducing agent to a substrate; a plasma excitation unit for exciting the oxidizing agent and the reducing agent into a plasma state; a heater for heating a substrate; and a control unit configured to control the oxidizing agent supply system, the reducing agent supply system, and the heater, such that (a) (a1) a process of supplying the oxidizing agent and the reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state; (a2) a process of supplying the reducing agent to a substrate by exciting it into a plasma state; and (b) a process of heat treating the substrate after (a) is performed, wherein in (a), the first surface and the second surface are oxidized, and in (b), the oxide formed on the first surface is sublimated while retaining the oxide formed on the second surface. Claim 27 A substrate processing system for processing a substrate, comprising: an oxidizing agent supply system for supplying an oxidizing agent to a substrate; a reducing agent supply system for supplying a reducing agent to a substrate; a plasma excitation unit for exciting the oxidizing agent and the reducing agent into a plasma state; a heater for heating a substrate; and a control unit configured to control the oxidizing agent supply system, the reducing agent supply system, and the heater so as to perform (a) (a1) a process of supplying the oxidizing agent and the reducing agent to a substrate having a first surface and a second surface by exciting them into a plasma state; (a2) a process of supplying the reducing agent to a substrate by exciting it into a plasma state; and (b) a process of heat treating the substrate after (a) is performed, wherein a concave portion is provided on the surface of the substrate, the first surface is the bottom surface of the concave portion, and the second surface is the side surface of the concave portion, or the side surface and top surface of the concave portion.

Images