Processing method, semiconductor device manufacturing method, processing device, and program

Abstract

To provide an image / video decoding method, a semiconductor device manufacturing method, a processing device, and a program for improving embedding characteristics when embedding the inside of a recess with a film.SOLUTION: A processing method comprises: a step (a) of adsorbing at least a part of a molecular structure of molecules constituting a precursor to a surface of a first material of a recess by supplying the precursor to a substrate on which the recess composed of the first material including a first element and a second material including a second element differing from the first element is formed on the surface, and forming an inhibitor layer on the surface of the first material; a step (b) of growing a film on a surface of the second material of the recess by supplying a deposition material to a substrate on which the inhibitor layer is formed on the surface of the first material; a step (c) of realizing a state that hydroxy group terminations are formed on the surface of the first material and the surface of the second material before the step (a) is carried out; and a step (d) of removing the hydroxy group termination formed on the surface of the second material before the step (a) is carried out.SELECTED DRAWING: None

Description

[Technical field]

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

[0002] As one step in the manufacturing process of a semiconductor device, a process of forming a film on a surface of a substrate is performed, and in this case, the film is sometimes formed so as to fill a recess provided on the surface of the substrate (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-183218 A [Patent Document 1] JP 2017-069407 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a technique for improving the filling characteristics when filling a recess with a film. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, (a) supplying a precursor to a substrate having a recess on its surface, the recess having an upper surface and a side surface made of a first material containing a first element and a bottom surface made of a second material containing a second element different from the first element, thereby adsorbing at least a part of a molecular structure of a molecule constituting the precursor to a surface of the first material in the recess, thereby forming a film-formation inhibiting layer on the surface of the first material; (b) supplying a film-forming substance to the substrate on which the film-formation inhibiting layer is formed on the surface of the first material to grow a film on the surface of the second material in the recess; Techniques for doing so are provided. Effect of the Invention

[0006] According to the present disclosure, it is possible to improve the filling characteristics when filling a recess with a film. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in one embodiment of the present disclosure, showing a processing furnace 202 portion in vertical cross section. [Diagram 2] FIG. 2 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferably used in one embodiment of the present disclosure, showing a processing furnace 202 portion in a cross-sectional view taken along line AA in FIG. [Diagram 3] FIG. 3 is a schematic configuration diagram of a controller 121 of a substrate processing apparatus suitably used in one embodiment of the present disclosure, and is a block diagram showing a control system of the controller 121. [Figure 4] FIG. 4 is a diagram showing a processing sequence according to an embodiment of the present disclosure. [Diagram 5]Fig. 5(a) is a partial cross-sectional enlarged view of the surface of a substrate having a laminated structure formed by alternately laminating a second material (SiGe) and a first material (Si) on the surface, an insulating film provided thereon, and a part of the sidewall of the laminated structure made of the second material (SiGe) removed to provide a recess in the sidewall of the laminated structure whose depth direction is parallel to the surface of the substrate (horizontal direction). Fig. 5(b) is a partial cross-sectional enlarged view of the surface of a substrate during a process of forming a silicon oxycarbide film (SiOC) on the substrate having the structure on the surface of Fig. 5(a) by the process sequence of this embodiment. Fig. 5(c) is a partial cross-sectional enlarged view of the surface of a substrate after a process of forming a silicon oxycarbide film (SiOC) on the substrate having the structure on the surface of Fig. 5(a) by the process sequence of this embodiment. FIG. 5(d) is an enlarged cross-sectional view of a portion of the surface of a substrate having the configuration in FIG. 5(a) on its surface after a process for forming a silicon oxycarbide film (SiOC) is performed using the process sequence in this embodiment, followed by annealing. [Figure 6] Fig. 6(a) is a partial cross-sectional enlarged view of the surface of a substrate having a laminated structure formed by alternately laminating a second material (SiGe) and a first material (Si) on the surface, an insulating film provided thereon, and a part of the sidewall of the laminated structure made of the second material (SiGe) removed to provide a recess in the sidewall of the laminated structure whose depth direction is parallel to the surface of the substrate (horizontal direction). Fig. 6(b) is a partial cross-sectional enlarged view of the surface of the substrate after a process for forming a silicon oxycarbide film (SiOC) on the substrate having the structure on the surface of Fig. 6(a) is performed by a conventional film forming method. Fig. 6(c) is a partial cross-sectional enlarged view of the surface of the substrate after an etching process is performed on the substrate having the structure on the surface of Fig. 6(b) to remove excess film formed on the top surface of the recess. [Figure 7] FIG. 7 is a cross-sectional TEM image of evaluation sample 1 in the example. [Figure 8] FIG. 8 is a cross-sectional TEM image of evaluation sample 2 in the example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] <One aspect of the present disclosure> Hereinafter, one embodiment of the present disclosure will be described mainly with reference to Figures 1 to 4 and 5(a) to 5(d). Note that the drawings used in the following description are all schematic, and the dimensional relationships of the elements, the ratios of the elements, etc. shown in the drawings do not necessarily match the actual ones. Furthermore, the dimensional relationships of the elements, the ratios of the elements, etc. between multiple drawings do not necessarily match.

[0009] (1) Configuration of the substrate processing device 1, the process furnace 202 has a heater 207 as a temperature regulator (heating unit). The heater 207 is cylindrical and is installed vertically by being supported by a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) gas by heat.

[0010] A reaction tube 203 is disposed concentrically with the heater 207 inside the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed in a cylindrical shape with a closed upper end and an open lower end. A manifold 209 is disposed concentrically with the reaction tube 203 below 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 upper end and a closed lower end. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 and is configured to support the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a seal member. The reaction tube 203 is installed vertically like the heater 207. The reaction tube 203 and the manifold 209 mainly constitute a processing vessel (reaction vessel). A processing chamber 201 is formed in a cylindrical hollow portion of the processing vessel. The processing chamber 201 is configured to be capable of accommodating a wafer 200 as a substrate. In the processing chamber 201, processing of the wafer 200 is performed.

[0011] Nozzles 249a to 249c serving as first to third supply units are provided in the processing chamber 201 so as to penetrate the sidewall of the manifold 209, respectively. The nozzles 249a to 249c are also referred to as first to third nozzles, respectively. The nozzles 249a to 249c are made of a heat-resistant material such as quartz or SiC. Gas supply pipes 232a to 232c are connected to the nozzles 249a to 249c, respectively. The nozzles 249a to 249c are different nozzles, and each of the nozzles 249a and 249c is provided adjacent to the nozzle 249b.

[0012] Gas supply pipes 232a-232c are provided with mass flow controllers (MFCs) 241a-241c, which are flow rate controllers (flow rate control parts), and valves 243a-243c, which are on-off valves, in order from the upstream side of the gas flow. Gas supply pipes 232d and 232f are connected to the gas supply pipe 232a downstream of the valve 243a. Gas supply pipes 232e and 232g are connected to the gas supply pipe 232b downstream of the valve 243b. Gas supply pipe 232h is connected to the gas supply pipe 232c downstream of the valve 243c. Gas supply pipes 232d-232h are provided with MFCs 241d-241h and valves 243d-243h in order from the upstream side of the gas flow. Gas supply pipes 232a-232h are made of a metal material, such as SUS.

[0013] As shown in FIG. 2, the nozzles 249a to 249c are provided in a circular space between the inner wall of the reaction tube 203 and the wafers 200 in a plan view, from the lower part to the upper part of the inner wall of the reaction tube 203, so as to rise upward in the arrangement direction of the wafers 200. That is, the nozzles 249a to 249c are provided in a region horizontally surrounding the wafer arrangement region on the side of the wafer arrangement region in which the wafers 200 are arranged, so as to extend along the wafer arrangement region. In a plan view, the nozzle 249b is disposed so as to face an exhaust port 231a (described later) on a straight line across the center of the wafer 200 loaded into the processing chamber 201. The nozzles 249a and 249c are disposed so as to sandwich a straight line L passing through the nozzle 249b and the center of the exhaust port 231a from both sides along the inner wall of the reaction tube 203 (the outer periphery of the wafer 200). The straight line L is also a straight line passing through the nozzle 249b and the center of the wafer 200. In other words, the nozzle 249c is provided on the opposite side of the nozzle 249a across the line L. The nozzles 249a and 249c are arranged symmetrically with respect to the line L. Gas supply holes 250a to 250c for supplying gas are provided on the side surfaces of the nozzles 249a to 249c, respectively. The gas supply holes 250a to 250c are each opened to face (face) the exhaust port 231a in a plan view, and are capable of supplying gas toward the wafer 200. A plurality of gas supply holes 250a to 250c are provided from the lower part to the upper part of the reaction tube 203.

[0014] A precursor (precursor gas) is supplied from the gas supply pipe 232a into the processing chamber 201 via the MFC 241a, the valve 243a, and the nozzle 249a.

[0015] A raw material (raw material gas), which is one of film forming substances (film forming gas), is supplied from the gas supply pipe 232b into the processing chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b.

[0016] A reactant (reaction gas), which is one of the film formation substances (film formation gas) and one of the reactants, is supplied from the gas supply pipe 232c into the processing chamber 201 via the MFC 241c, the valve 243c, and the nozzle 249c.

[0017] A catalyst (catalyst gas), which is one of the film forming substances (film forming gas) and also one of the reactants, is supplied from the gas supply pipe 232d into the processing chamber 201 via the MFC 241d, the valve 243d, the gas supply pipe 232a, and the nozzle 249a.

[0018] An etchant (etching gas) is supplied from the gas supply pipe 232e into the processing chamber 201 via the MFC 241e, the valve 243e, the gas supply pipe 232b, and the nozzle 249b.

[0019] From the gas supply pipes 232f to 232h, an inert gas is supplied via the MFCs 241f to 241h, the valves 243f to 243h, the gas supply pipes 232a to 232c, and the nozzles 249a to 249c into the processing chamber 201. The inert gas acts as a purge gas, a carrier gas, a dilution gas, or the like.

[0020] A precursor supply system is mainly composed of the gas supply pipe 232a, the MFC 241a, and the valve 243a. A raw material supply system is mainly composed of the gas supply pipe 232b, the MFC 241b, and the valve 243b. A reactant supply system is mainly composed of the gas supply pipe 232c, the MFC 241c, and the valve 243c. A catalyst supply system is mainly composed of the gas supply pipe 232d, the MFC 241d, and the valve 243d. An etching agent supply system is mainly composed of the gas supply pipe 232e, the MFC 241e, and the valve 243e. An inert gas supply system is mainly composed of the gas supply pipes 232f to 232h, the MFCs 241f to 241h, and the valves 243f to 243h. Either or all of the raw material supply system and the reactant supply system are also referred to as a film forming material supply system. The source supply system, the reactant supply system, and the catalyst supply system may each be referred to as a deposition material supply system. The reactant supply system and the catalyst supply system may each be referred to as a reactant supply system.

[0021] Any or all of the various supply systems described above may be configured as an integrated supply system 248 in which the valves 243a-243h, the MFCs 241a-241h, etc. are integrated. The integrated supply system 248 is connected to each of the gas supply pipes 232a-232h, and is configured so that the supply operation of various substances (various gases) into the gas supply pipes 232a-232h, that is, the opening and closing operation of the valves 243a-243h and the flow rate adjustment operation by the MFCs 241a-241h, etc., are controlled by a controller 121 described later. The integrated supply system 248 is configured as an integrated or split type integrated unit, and can be attached and detached to and from the gas supply pipes 232a-232h, etc., in units of integrated units, and is configured so that maintenance, replacement, expansion, etc. of the integrated supply system 248 can be performed in units of integrated units.

[0022] An exhaust port 231a for exhausting the atmosphere in the processing chamber 201 is provided at the lower side of the side wall of the reaction tube 203. As shown in FIG. 2, the exhaust port 231a is provided at a position facing the nozzles 249a to 249c (gas supply holes 250a to 250c) across the wafer 200 in a plan view. The exhaust port 231a may be provided along the side wall of the reaction tube 203 from the lower part to the upper part, that is, along the wafer arrangement area. An exhaust pipe 231 is connected to the exhaust port 231a. A vacuum pump 246 as a vacuum exhaust device is connected to the exhaust pipe 231 via a pressure sensor 245 as a pressure detector (pressure detection unit) for detecting the pressure in the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 as a pressure regulator (pressure adjustment unit). The APC valve 244 can evacuate and stop the evacuation of the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operating, and further, can adjust the pressure inside the processing chamber 201 by adjusting the valve opening based on pressure information detected by the pressure sensor 245 while the vacuum pump 246 is operating. An exhaust system is mainly configured by the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may be included in the exhaust system.

[0023] Below the manifold 209, a seal cap 219 is provided as a furnace port cover body capable of airtightly closing the lower end opening of the manifold 209. The seal cap 219 is made of a metal material such as SUS, and is formed in a disk shape. An O-ring 220b is provided on the upper surface of the seal cap 219 as a seal member that abuts against the lower end of the manifold 209. Below the seal cap 219, a rotation mechanism 267 is provided for rotating the boat 217, which will be described later. A rotation shaft 255 of the rotation mechanism 267 is connected to the boat 217 through the seal cap 219. The rotation mechanism 267 is configured to rotate the wafers 200 by rotating the boat 217. The seal cap 219 is configured to be vertically raised and lowered by a boat elevator 115 as a lifting mechanism installed outside the reaction tube 203. The boat elevator 115 is configured as a transfer device (transfer mechanism) that transfers (transports) the wafers 200 into and out of the processing chamber 201 by raising and lowering the seal cap 219.

[0024] A shutter 219s is provided below the manifold 209 as a furnace port cover that can airtightly close the lower end opening of the manifold 209 when the seal cap 219 is lowered and the boat 217 is carried out of the processing chamber 201. The shutter 219s is made of a metal material such as SUS and is formed in a disk shape. An O-ring 220c is provided on the upper surface of the shutter 219s as a seal member that comes into contact with the lower end of the manifold 209. The opening and closing operation (lifting and lowering operation, rotating operation, etc.) of the shutter 219s is controlled by a shutter opening and closing mechanism 115s.

[0025] The boat 217 as a substrate support is configured to support a plurality of wafers 200, for example 25 to 200, in multiple stages in a horizontal position and aligned vertically with their centers aligned, i.e., arranged at intervals. The boat 217 is made of a heat-resistant material such as quartz or SiC. At the bottom of the boat 217, heat insulating plates 218 made of a heat-resistant material such as quartz or SiC are supported in multiple stages.

[0026] A temperature sensor 263 serving as a temperature detector is installed in the reaction tube 203. By adjusting the power supply to the heater 207 based on temperature information detected by the temperature sensor 263, the temperature distribution in the process chamber 201 becomes a desired one. The temperature sensor 263 is installed along the inner wall of the reaction tube 203.

[0027] As shown in Fig. 3, the controller 121, which is a control unit (control means), is configured as a computer including a CPU (Central Processing Unit) 121a, a RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, the storage device 121c, and the I / O port 121d are configured to be able to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122 configured as, for example, a touch panel, is connected to the controller 121. An external storage device 123 can also be connected to the controller 121.

[0028] The storage device 121c is composed of, for example, a flash memory, a hard disk drive (HDD), a solid state drive (SSD), etc. A control program for controlling the operation of the substrate processing apparatus, a process recipe in which procedures and conditions of the substrate processing described later are described, etc. are readably stored in the storage device 121c. The process recipe is a combination of procedures in the substrate processing described later, which are executed by the controller 121 in the substrate processing apparatus, so that a predetermined result can be obtained, and functions as a program. Hereinafter, the process recipe, the control program, etc. are collectively referred to simply as a program. In addition, the process recipe is also simply referred to as a recipe. In this specification, when the word program is used, it may include only a recipe, only a control program, or both. The RAM 121b is configured as a memory area (work area) in which the programs and data read by the CPU 121a are temporarily stored.

[0029] The I / O port 121d is connected to the above-mentioned MFCs 241a to 241h, valves 243a to 243h, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotation mechanism 267, boat elevator 115, shutter opening / closing mechanism 115s, and the like.

[0030] The CPU 121a is configured to be able to read and execute a control program from the storage device 121c, and to read a recipe from the storage device 121c in response to an input of an operation command from the input / output device 122, etc. The CPU 121a is configured to be able to control the flow rate adjustment operation of various substances (various gases) by the MFCs 241a to 241h, the opening and closing operation of the valves 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 start and stop 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 and lowering 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, etc., in accordance with the contents of the read recipe.

[0031] The controller 121 can be configured by installing the above-mentioned program stored in the external storage device 123 in 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, and 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. When the term recording media is used in this specification, it may include only the storage device 121c alone, only the external storage device 123 alone, or both of them. The program may be provided to the computer using a communication means such as the Internet or a dedicated line without using the external storage device 123.

[0032] (2) Substrate processing An example of a processing sequence for forming a film in a recess provided on the surface of a wafer 200 as a substrate so as to fill the recess, as one step in a manufacturing process of a semiconductor device, using the above-mentioned substrate processing apparatus will be described mainly with reference to Figure 4 and Figures 5(a) to 5(d). In the following description, the operation of each part constituting the substrate processing apparatus is controlled by a controller 121.

[0033] As shown in FIG. 5(a), the surface of the wafer 200 has a recess whose upper and side surfaces are made of a first material containing a first element and whose bottom surface is made of a second material containing a second element different from the first element, and whose depth direction is parallel to the surface of the wafer 200 (horizontal direction). FIG. 5(a) shows an example in which the first element is silicon (Si), the second element is germanium (Ge), the first material is silicon (Si), and the second material is silicon germanium (SiGe). That is, in this example, the second material contains the second element in addition to the first element. The wafer 200 is also made of single crystal Si. That is, the wafer 200 contains the first element.

[0034] More specifically, a laminated structure formed by alternately stacking a second material (SiGe) and a first material (Si) is provided on the surface of the wafer 200, and an insulating film (insulator) is provided thereon. That is, a laminated structure formed by alternately stacking a silicon germanium (SiGe) film and a silicon (Si) film is provided on the surface of the wafer 200, and an insulating film (insulator) is provided thereon. By removing a part of the portion of the sidewall of the laminated structure of the SiGe film and the Si film that is composed of the SiGe film, a recess is provided on the sidewall of the laminated structure, whose upper surface and side surface are composed of the first material (Si) and whose bottom surface is composed of the second material (SiGe), and whose depth direction is parallel to the surface of the wafer 200 (horizontal direction). In this specification, as shown in FIG. 5(a), the portion of the recess made of the second material (SiGe) is referred to as the bottom surface, and based on that, the portion of the recess made of the first material (Si), which is in contact with the bottom surface and is arranged perpendicular to the bottom surface is referred to as the side surface, and the portion of the recess made of the first material (Si), which is not in contact with the bottom surface and is arranged parallel to the bottom surface is referred to as the top surface.

[0035] The processing sequence shown in Figure 4 is as follows: a step A of supplying a precursor to a wafer 200 having a recess on its surface, the recess having an upper surface and a side surface made of a first material containing a first element and a bottom surface made of a second material containing a second element different from the first element, thereby adsorbing at least a part of a molecular structure of a molecule constituting the precursor to a surface of the first material in the recess, thereby forming a film formation suppressing layer on the surface of the first material; The method includes a step B of supplying a film formation substance to the wafer 200 having the film formation inhibiting layer formed on the surface of the first material, thereby growing a film on the surface of the second material in the recessed portion.

[0036] As shown in FIG. 4, in step B, Step B1 of supplying a raw material as a film forming material to the wafer 200; Step B2 of supplying an oxidizing agent as a reactant to the wafer 200 as a deposition material; The above-mentioned non-simultaneous cycle is repeated a predetermined number of times, whereby the film is grown starting from the bottom surface of the recess, and the film is grown bottom-up in the recess, so that the recess is filled with the film.

[0037] At this time, in at least one of step B1 and step B2, a catalyst may be further supplied as a film forming material to the wafer 200. Fig. 4 shows an example in which a catalyst is further supplied as a film forming material to the wafer 200 in each of step B1 and step B2.

[0038] 4 further includes a step C of supplying an oxidizing agent as a reactant to the wafer 200 and oxidizing the surface of the first material to form hydroxyl group terminations on the surface of the first material before performing step A. At this time, the surface of the second material is also oxidized to form hydroxyl group terminations on the surface of the second material.

[0039] 4 further includes step D, which is performed after step C and before step A, of heating the wafer 200 and performing annealing (hereinafter also referred to as ANL) to sublimate the oxide formed on the surface of the second material, thereby removing the hydroxyl termination formed on the surface of the second material. At this time, the hydroxyl termination formed on the surface of the second material is removed while leaving the hydroxyl termination formed on the surface of the first material. As a result, the hydroxyl termination is formed on the surface of the first material before performing step A, and either no hydroxyl termination is formed on the surface of the second material before performing step A, or the amount of hydroxyl termination is much less than the amount of hydroxyl termination on the surface of the first material. Hereinafter, the hydroxyl termination is also referred to as OH termination.

[0040] Moreover, the processing sequence shown in FIG. 4 further includes, before performing step C, step E of supplying an etching agent to the wafer 200 and removing native oxide films on the surfaces of the first material and the second material.

[0041] In addition, the processing sequence shown in FIG. 4 further includes step F, in which after performing step B, the wafer 200 is heated and subjected to a thermal treatment, thereby performing post-treatment, i.e., post-treatment (hereinafter also referred to as PT), on the film formed to fill the recess.

[0042] In this embodiment, an example will be described in which the first element is Si, the second element is Ge, the first material is Si, and the second material is SiGe, and in step B, a silicon oxide carbon 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), is grown as the film.

[0043] In this specification, the above-mentioned processing sequence may be expressed as follows for convenience: Similar notations will be used in the following explanations of modified examples and other aspects.

[0044] Etching agent → Oxidizing agent → ANL → Precursor → (raw material + catalyst → Oxidizing agent + catalyst) × n → PT

[0045] In this specification, the term "wafer" may refer to the wafer itself or a laminate of the wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of the wafer" may refer to the surface of the wafer itself or the surface of a predetermined layer or the like formed on the wafer. In this specification, the phrase "forming a predetermined layer on a wafer" may refer to forming a predetermined layer directly on the surface of the wafer itself or forming a predetermined layer on a layer or the like formed on the wafer. In this specification, the term "substrate" is synonymous with the term "wafer".

[0046] (Wafer charge and boat load) When a plurality of wafers 200 are loaded into the boat 217 (wafer charge), the shutter 219s is moved by the shutter opening / closing mechanism 115s to open the lower end opening of the manifold 209 (shutter open). Thereafter, as shown in Fig. 1, the boat 217 supporting the plurality of wafers 200 is lifted by the boat elevator 115 and carried into the processing chamber 201 (boat load). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0047] (Pressure and temperature regulation) The processing chamber 201, i.e., the space in which the wafer 200 is present, is evacuated (reduced pressure exhaust) by the vacuum pump 246 so that the pressure inside the processing chamber 201 is a desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback-controlled based on the measured pressure information. Also, the wafer 200 inside the processing chamber 201 is heated by the heater 207 so that the processing temperature is a desired processing temperature. At this time, the power supply to the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the processing chamber 201 has a desired temperature distribution. Also, the rotation mechanism 267 starts rotating the wafer 200. The evacuation inside the processing chamber 201 and the heating and rotation of the wafer 200 are all continued at least until the processing of the wafer 200 is completed.

[0048] (Step E: Remove the native oxide film) An etchant is then applied to the wafer 200 .

[0049] Specifically, the valve 243e is opened to allow an etchant (etching gas) to flow into the gas supply pipe 232e. The flow rate of the etchant is adjusted by the MFC 241e, and the etchant is supplied into the processing chamber 201 via the gas supply pipe 232b and the nozzle 249b, and is exhausted from the exhaust port 231a. At this time, the etchant is supplied to the wafer 200 from the side of the wafer 200 (etchant supply). At this time, the valves 243f to 243h may be opened to supply an inert gas into the processing chamber 201 via each of the nozzles 249a to 249c.

[0050] By supplying an etching agent to the wafer 200 under processing conditions described below, it is possible to remove the native oxide film formed on the surface of the wafer 200. That is, it is possible to remove the native oxide film on the surfaces of the first material and the second material on the surface of the wafer 200. Specifically, it is possible to remove the native oxide film on the surface of a recessed portion on the surface of the wafer 200, the upper surface and the side surface of which are made of the first material (Si) and the bottom surface of which is made of the second material (SiGe), and the depth direction of which is parallel to the surface of the wafer 200 (horizontal direction).

[0051] After removing the natural oxide film formed on the surface of the wafer 200, the valve 243e is closed to stop the supply of the etching agent into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove gaseous substances remaining in the processing chamber 201 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, and the processing chamber 201 is purged (purged).

[0052] The processing conditions for supplying the etching agent are as follows: Treatment temperature: room temperature (25°C) to 200°C, preferably 50 to 150°C Processing pressure: 10~13332Pa, 20~1333Pa Etching agent supply flow rate: 0.5 to 5 slm, preferably 0.5 to 2 slm Etching agent supply time: 1 to 120 minutes, preferably 1 to 60 minutes Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm Examples include:

[0053] The processing conditions for purging are as follows: Processing temperature: Room temperature (25℃) to 500℃ Processing pressure: 1~30Pa Inert gas supply flow rate (per gas supply pipe): 0.5 to 20 slm Inert gas supply time: 1 to 120 seconds, preferably 1 to 60 seconds Examples include:

[0054] In this specification, the expression of a numerical range such as "25 to 200°C" means that the lower limit and the upper limit are included in the range. Therefore, for example, "25 to 200°C" means "25°C or more and 200°C or less". The same applies to other numerical ranges. In this specification, the process temperature means the temperature of the wafer 200 or the temperature inside the process chamber 201, and the process pressure means the pressure inside the process chamber 201. A gas supply flow rate of 0 slm means that the gas is not supplied. These also apply to the following explanations.

[0055] As the etching agent, for example, a fluorine (F)-containing gas can be used. As the F-containing gas, for example, hydrogen fluoride (HF) gas, fluorine (F2) gas, etc. can be used. As the etching agent, other than these, for example, an HF aqueous solution, etc. can also be used. That is, the etching agent may be a gaseous substance or a liquid substance. Also, the etching agent may be a liquid substance such as a mist-like substance. As the etching agent, one or more of these can be used.

[0056] As the inert gas, nitrogen (N2) gas, argon (Ar) gas, helium (He) gas, neon (Ne) gas, xenon (Xe) gas, or other rare gases can be used. This also applies to each step described later. As the inert gas, one or more of these can be used.

[0057] (Step C: Oxidation) Thereafter, an oxidizing agent (oxidizing gas) is supplied to the wafer 200 as a reactant.

[0058] Specifically, the valve 243c is opened, and an oxidizing agent, which is one of the reactants, is flowed into the gas supply pipe 232c as a reactant. The flow rate of the oxidizing agent is adjusted by the MFC 241c, and the oxidizing agent is supplied into the processing chamber 201 through the nozzle 249c, and is exhausted from the exhaust port 231a. At this time, the oxidizing agent is supplied to the wafer 200 from the side of the wafer 200 (oxidizing agent supply). At this time, the valve 243d may be opened, and a catalyst may be flowed into the gas supply pipe 232d. In this case, the catalyst is adjusted in flow rate by the MFC 241d, and the catalyst is supplied into the processing chamber 201 through the gas supply pipe 232a and the nozzle 249a, and is mixed with the oxidizing agent in the processing chamber 201, and is exhausted from the exhaust port 231a. At this time, a mixture of the catalyst and the oxidizing agent (mixed gas) is supplied to the wafer 200 from the side of the wafer 200. At this time, the valves 243f to 243h may be opened to supply an inert gas into the processing chamber 201 through the nozzles 249a to 249c, respectively.

[0059] By supplying an oxidizing agent or a mixture of an oxidizing agent and a catalyst to the wafer 200 under processing conditions described below, the surface of the first material (Si) on the surface of the wafer 200 after removing the native oxide film can be oxidized to form OH termination on the surface of the first material (Si). An oxide film (oxide) such as a silicon oxide film (SiO film) is formed on the surface of the first material (Si), and OH termination is formed on the surface. By supplying a mixture of an oxidizing agent and a catalyst to the wafer 200, the oxidation rate can be increased at low temperatures. However, in cases where it is necessary to lower the oxidation rate or to adjust the oxidation rate by temperature, the supply of the catalyst can be omitted.

[0060] At this time, the surface of the second material (SiGe) on the surface of the wafer 200 is also oxidized, and OH termination is also formed on the surface of the second material (SiGe). An oxide film (oxide) such as a germanium oxide film (GeO film) or a silicon germanium oxide film (SiGeO film) is formed on the surface of the second material (SiGe), and OH termination is formed on the surface.

[0061] After forming OH termination on the surface of the first material (Si) on the surface of the wafer 200, the valve 243d is closed to stop the supply of the oxidizing agent into the processing chamber 201. At this time, if a catalyst is being supplied at the same time, the valve 243d is closed to also stop the supply of the catalyst into the processing chamber 201. Then, gaseous substances remaining in the processing chamber 201 are removed from the processing chamber 201 (purging) using the same processing procedure and processing conditions as those for purging in step E.

[0062] The treatment conditions for the oxidant supply are as follows: Treatment temperature: room temperature (25°C) to 500°C, preferably room temperature to 300°C Treatment pressure: 1 to 101325 Pa, preferably 1 to 13332 Pa Oxidant supply flow rate: 0.1 to 10 slm, preferably 0.5 to 5 slm Oxidizing agent supply time: 1 to 120 minutes, preferably 1 to 60 minutes Catalyst supply flow rate: 0~10000sccm Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm Examples include:

[0063] As the oxidizing agent, for example, an oxygen (O)-containing gas or an oxygen (O) and hydrogen (H)-containing gas can be used. As the O-containing gas, for example, oxygen (O2) gas, ozone (O3) gas, nitrous oxide (N2O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, carbon monoxide (CO) gas, carbon dioxide (CO2) gas, etc. can be used. As the O- and H-containing gas, for example, water vapor (H2O gas), hydrogen peroxide (H2O2), hydrogen (H2) gas + oxygen (O2) gas, H2 gas + ozone (O3) gas, etc. can be used. Note that the O- and H-containing gas is also an O-containing gas. In addition to these, a cleaning solution, for example, a cleaning solution containing ammonia water, hydrogen peroxide water, and pure water, may be used as the oxidizing agent. That is, oxidation may be performed by APM cleaning. In this case, the oxidation can be performed by exposing the wafer 200 to the cleaning solution. As such, the oxidizing agent may be a gaseous substance or a liquid substance. The oxidizing agent may be a liquid substance such as a mist substance, etc. As the oxidizing agent, one or more of these can be used.

[0064] As the catalyst, for example, an amine-based gas containing carbon (C), nitrogen (N), and hydrogen (H) can be used. Examples of the amine-based gas include pyridine (C5H5N) gas, aminopyridine (C5H6N2) gas, picoline (C6H7N) gas, lutidine (C7H9N) gas, piperazine (C4H 10 N2) gas, piperidine (C5H 11 For example, a cyclic amine gas such as triethylamine ((C2H5)3N, abbreviated as TEA) gas or a chain amine gas such as diethylamine ((C2H5)2NH, abbreviated as DEA) gas can be used. This also applies to step B described later.

[0065] (Step D: ANL) After forming OH termination on the surface of the first material (Si), the inside of the processing chamber 201 is purged as described above. In parallel with this purging, the wafer 200 is heated and annealed. As described above, the heating of the wafer 200 continues at least until the processing of the wafer 200 is completed, and therefore, when the supply of the oxidizing agent and catalyst is stopped, the annealing is started.

[0066] By annealing the wafer 200 under processing conditions described below, oxides such as GeO formed on the surface of the second material (SiGe) can be sublimated, thereby removing the OH termination formed on the surface of the second material (SiGe).

[0067] At this time, not only the second material (SiGe) but also the first material (Si) is heated in the same manner, but since an oxide film such as a SiO film formed on the surface of the first material (Si) has a strong Si-O bond, it will not sublime under the processing conditions described below. In other words, even if annealing is performed, the OH termination formed on the surface of the first material (Si) can be maintained (preserved) without being removed.

[0068] In this way, in the annealing treatment in step D, it is possible to remove oxides such as GeO formed on the surface of the second material (SiGe) while leaving (maintaining) an oxide film such as a SiO film formed on the surface of the first material (Si). That is, in the annealing treatment in step D, it is possible to remove OH terminations formed on the surface of the second material (SiGe) while leaving (maintaining) OH terminations formed on the surface of the first material (Si). Note that there are cases where not all of the OH terminations formed on the surface of the second material (SiGe) are removed, and only a small portion of them remains.

[0069] As a result, the surface of the first material (Si) before step A is subjected to has OH termination formed on its surface. Also, the surface of the second material (SiGe) before step A is subjected to has no OH termination formed on its surface, or has an amount of OH termination formed on its surface that is far less than the amount of OH termination on the surface of the first material (Si). That is, the amount (density, concentration) of OH termination on the surface of the first material (Si) before step A is subjected to is greater (higher) than the amount (density, concentration) of OH termination on the surface of the second material (SiGe).

[0070] The processing conditions for annealing (ANL) are as follows: Treatment temperature: 100 to 500°C, preferably 100 to 300°C Treatment pressure: 1 to 13332 Pa, preferably 1 to 1333 Pa Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm Annealing time: 1 to 120 minutes, preferably 1 to 60 minutes Examples include:

[0071] (Step A: Formation of the film formation suppression layer) Then, the precursor is delivered to the wafer 200 .

[0072] Specifically, the valve 243a is opened to allow the precursor to flow into the gas supply pipe 232a. The precursor has a flow rate adjusted by the MFC 241a, is supplied into the processing chamber 201 via the nozzle 249a, and is exhausted from the exhaust port 231a. At this time, the precursor is supplied to the wafer 200 from the side of the wafer 200 (precursor supply). At this time, the valves 243f to 243h may be opened to supply an inert gas into the processing chamber 201 via each of the nozzles 249a to 249c.

[0073] By supplying the precursor to the wafer 200 under processing conditions described below, at least a part of the molecular structure of the molecules constituting the precursor is selectively (preferentially) adsorbed to the surface of the first material (Si) among the first material (Si) and the second material (SiGe) in the recesses on the surface of the wafer 200, and a film formation suppressing layer can be selectively (preferentially) formed on the surface of the first material (Si). Specifically, while suppressing the adsorption of at least a part of the molecular structure of the molecules constituting the precursor to the surface of the second material (SiGe), it is possible to selectively adsorb at least a part of the molecular structure of the molecules constituting the precursor to the surface of the first material (Si) by reacting the precursor with the OH group terminating the surface of the first material (Si). This makes it possible to terminate the surface of the first material (Si) with at least a part of the molecular structure of the molecules constituting the precursor. At least a part of the molecular structure of the molecule constituting the precursor may be, for example, a trialkylsilyl group such as a trimethylsilyl group (Si-Me3) or a triethylsilyl group (Si-Et3). In these cases, the Si of the trimethylsilyl group or the triethylsilyl group is adsorbed to the surface of the first material (Si), and the outermost surface of the first material (Si) is terminated with an alkyl group such as a methyl group or an ethyl group. At least a part of the molecular structure of the molecule constituting the precursor that terminates the surface of the first material (Si), for example, an alkyl group (alkylsilyl group) such as a methyl group (trimethylsilyl group) or an ethyl group (triethylsilyl group), acts as a film formation inhibition layer (film formation suppression layer) that prevents the adsorption of the raw material to the surface of the first material (Si) in the film formation process (selective growth) described later and inhibits the progress of the film formation reaction on the surface of the first material (Si), that is, as an inhibitor.

[0074] In this step, at least a part of the molecular structure of the molecules constituting the precursor may be adsorbed to a part of the surface of the second material (SiGe), but the amount of adsorption is small, and the amount of adsorption to the surface of the first material (Si) is overwhelmingly larger. Such selective (preferential) adsorption is possible because the process conditions in this step are set to conditions under which the precursor does not undergo gas phase decomposition in the process chamber 201. Also, this is because the surface of the first material (Si) is OH-terminated over its entire area, whereas most areas of the surface of the second material (SiGe) are not OH-terminated. In this step, since the precursor does not undergo gas phase decomposition in the processing chamber 201, at least a portion of the molecular structure of the molecules constituting the precursor is not deposited in multiple layers on the surface of the first material (Si) and the surface of the second material (SiGe), and at least a portion of the molecular structure of the molecules constituting the precursor is selectively adsorbed onto the surface of the first material (Si), thereby selectively terminating the surface of the first material (Si) with at least a portion of the molecular structure of the molecules constituting the precursor.

[0075] After selectively forming a film formation suppression layer on the surface of the first material (Si), the valve 243a is closed to stop the supply of the precursor into the processing chamber 201. Then, gaseous substances remaining in the processing chamber 201 are removed from the processing chamber 201 (purging) by the same processing procedure and processing conditions as those for purging in step E.

[0076] The processing conditions for the precursor supply are as follows: Treatment temperature: room temperature (25°C) to 500°C, preferably room temperature to 250°C Processing pressure: 5~1000Pa Precursor supply flow rate: 1-3000sccm, preferably 1-500sccm Precursor supply time: 1 second to 120 minutes, preferably 30 seconds to 60 minutes Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm Examples include:

[0077] As the precursor, for example, a substance containing one or more atoms to which a first functional group and a second functional group are directly bonded can be used. The first functional group in the precursor is preferably a functional group that enables the precursor to be chemically adsorbed to an adsorption site (e.g., OH termination) on the surface of the first material (Si). The first functional group preferably contains an amino group, and more preferably contains a substituted amino group. When the precursor contains an amino group (preferably a substituted amino group), the amount of the precursor chemically adsorbed to the surface of the first material (Si) can be increased. In particular, from the viewpoint of the adsorption to the surface of the first material (Si), it is preferable that all of the first functional groups of the precursor are substituted amino groups.

[0078] The substituent of the substituted amino group is preferably an alkyl group, more preferably an alkyl group having 1 to 5 carbon atoms, and particularly preferably an alkyl group having 1 to 4 carbon atoms. The alkyl group of the substituted amino group may be linear or branched. Specific examples of the alkyl group of the substituted amino group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an isopropyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. The number of the substituent of the substituted amino group is 1 or 2, and is preferably 2. When the number of the substituent of the substituted amino group is 2, the two substituents may be the same or different.

[0079] The number of first functional groups in the precursor is preferably 2 or less, and more preferably 1. When the precursor has a plurality of first functional groups, the first functional groups may be the same or different.

[0080] The second functional group in the precursor is preferably a functional group capable of modifying the outermost surface of the first material (Si) into a film formation inhibiting region. The second functional group is preferably a chemically stable functional group, more preferably a hydrocarbon group. The hydrocarbon group may be an aliphatic hydrocarbon group such as an alkyl group, an alkenyl group, an alkynyl group, or the like, or may be an aromatic hydrocarbon group. Among these, the hydrocarbon group is preferably an alkyl group. In particular, from the viewpoint of high chemical stability, it is preferable that all the second functional groups possessed by the precursor are alkyl groups.

[0081] The alkyl group as the second functional group is more preferably an alkyl group having 1 to 5 carbon atoms, and particularly preferably an alkyl group having 1 to 4 carbon atoms. The alkyl group of the substituted amino group may be linear or branched. Specific examples of the alkyl group of the substituted amino group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an isopropyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group.

[0082] The number of second functional groups in the precursor may be an integer equal to or greater than 1. When the number of first functional groups in the precursor is 1, the number of second functional groups in the precursor is preferably 3. When the number of first functional groups in the precursor is 2, the number of second functional groups in the precursor is preferably 2. The multiple second functional groups in the precursor may be the same or different.

[0083] In the precursor, the atom to which the first functional group and the second functional group are directly bonded may be a carbon (C) atom, a silicon (Si) atom, a germanium (Ge) atom, a tetravalent metal atom, etc. Here, the tetravalent metal atom may be a titanium (Ti) atom, a zirconium (Zr) atom, a hafnium (Hf) atom, a molybdenum (Mo) atom, a tungsten (W) atom, etc. Note that the atom to which the first functional group and the second functional group are directly bonded may be a metal atom capable of bonding with four or more ligands, in addition to a tetravalent metal atom. In this case, the number of the second functional groups can be increased, and a strong inhibitor effect can be exhibited.

[0084] Among these, the atom to which the first functional group and the second functional group are directly bonded is preferably a C atom, a Si atom, or a Ge atom. This is because, when any of a C atom, a Si atom, and a Ge atom is used as the atom to which the first functional group and the second functional group are directly bonded, at least one of the characteristics of high adsorption of the precursor to the surface of the first material (Si) and high chemical stability of the precursor, i.e., residue derived from the precursor, after adsorption to the surface of the first material (Si) can be obtained. Among these, the atom to which the first functional group and the second functional group are directly bonded is more preferably a Si atom. This is because, when a Si atom is used as the atom to which the first functional group and the second functional group are directly bonded, both characteristics of high adsorption of the precursor to the surface of the first material (Si) and high chemical stability of the precursor, i.e., residue derived from the precursor, after adsorption to the surface of the first material (Si) can be obtained in a well-balanced manner. As described above, the atom to which the first functional group and the second functional group are directly bonded has the first functional group and the second functional group directly bonded thereto, but in addition to these, a hydrogen (H) atom or a third functional group may be bonded thereto.

[0085] The third functional group bonded to the atom to which the first and second functional groups are directly bonded may be any functional group other than the functional groups described above as the first and second functional groups. Examples of the third functional group include functional groups formed by appropriately combining two or more of a C atom, a Si atom, a Ge atom, a tetravalent metal atom, a metal atom capable of bonding to four or more ligands, an O atom, a nitrogen (N) atom, and an H atom.

[0086] The precursor contains one or more atoms to which the first and second functional groups are directly bonded, but may contain two or more atoms to which the first and second functional groups are directly bonded. Hereinafter, the atom to which the first and second functional groups are directly bonded is also referred to as atom X for convenience.

[0087] The precursor preferably has a structure containing a tetravalent atom to which the first functional group and the second functional group are directly bonded. In particular, the precursor more preferably has a structure containing a tetravalent atom to which only the first functional group and the second functional group are directly bonded. In particular, the precursor particularly preferably has a structure containing one Si to which only the first functional group and the second functional group are directly bonded. That is, the precursor particularly preferably has a structure in which only the first functional group and the second functional group are directly bonded to Si as a central atom.

[0088] The precursor preferably has a structure containing one amino group in one molecule. Among them, the precursor more preferably has a structure containing one amino group and at least one alkyl group in one molecule. Among them, the precursor more preferably has a structure containing one amino group and three alkyl groups in one molecule. Also, the precursor preferably has a structure in which one amino group is bonded to the central atom Si. Among them, the precursor more preferably has a structure in which one amino group and at least one alkyl group are bonded to the central atom Si. Among them, the precursor more preferably has a structure in which one amino group and three alkyl groups are bonded to the central atom Si. In addition, the amino group is preferably a substituted amino group as described above. The substituent of the substituted amino group is as described above.

[0089] As the precursor, for example, it is preferable to use a compound represented by the following formula 1.

[0090] Equation 1: [R 1 ]n 1 -(X)-[R 2 ]m 1 In formula 1, R 1 represents the first functional group directly bonded to X, R 2 represents a second functional group or an H atom directly bonded to X, X represents a tetravalent atom selected from the group consisting of a C atom, a Si atom, a Ge atom, and a tetravalent metal atom, n 1 represents 1 or 2, m 1 represents 2 or 3.

[0091] R 1 The first functional group represented by the formula (I) has the same meaning as the first functional group described above, and preferred examples are also the same. 1 If is 2, there are two R 1 may be the same or different. 2 The second functional group represented by the formula (I) has the same meaning as the second functional group described above, and preferred examples are also the same. 1 If is 2 or 3, then there are 2 or 3 R 2 One or two of R may be H atoms and the rest may be second functional groups, or all of R may be second functional groups. 2 When all of are second functional groups, all of the second functional groups may be the same or different. The tetravalent atom represented by X is preferably a Si atom. 2 is preferably 1. 2 As the number, 3 is preferable.

[0092] As the precursor, for example, (dimethylamino)trimethylsilane ((CH3)2NSi(CH3)3, abbreviated as DMATMS), (diethylamino)triethylsilane ((C2H5)2NSi(C2H5)3, abbreviated as DEATES), (dimethylamino)triethylsilane ((CH3)2NSi(C2H5)3, abbreviated as DMATES), (diethylamino)trimethylsilane ((C2H5)2NSi(CH3)3, abbreviated as DEATMS), (trimethylsilyl)amine ((CH3)3SiNH2, abbreviated as TMSA), (triethylsilyl)amine ((C2H5)3SiNH2, abbreviated as TESA), (dimethylamino)silane ((CH3)2NSiH3, abbreviated as DMAS), (diethylamino)silane ((C2H5)2NSiH3, abbreviated as DEAS), etc. can be used.

[0093] Examples of the precursor include bis(dimethylamino)dimethylsilane ([(CH3)2N]2Si(CH3)2, abbreviated as BDMADMS), bis(diethylamino)diethylsilane ([(C2H5)2N]2Si(C2H5)2, abbreviated as BDEADES), bis(dimethylamino)diethylsilane ([(CH3)2N]2Si(C2H5)2, abbreviated as BDMADES), and bis(diethylamino)diethylsilane ([(CH3)2N]2Si(C2H5)2, abbreviated as BDMADES). dimethylaminosilane ([(C2H5)2N]2Si(CH3)2, abbreviation: BDEADMS), bis(dimethylamino)silane ([(CH3)2N]2SiH2, abbreviation: BDMAS), bis(dimethylaminodimethylsilyl)ethane ([(CH3)2N(CH3)2Si]2C2H6, abbreviation: BDMADMSE), bis(dipropylamino)silane ([(C3H7)2N]2SiH2, abbreviation: B DPAS), bis(dipropylamino)dimethylsilane ([(C3H7)2N]2Si(CH3)2, abbreviated as BDPADMS), bis(dipropylamino)diethylsilane ([(C3H7)2N]2Si(C2H5)2, abbreviated as BDPADES), (dimethylsilyl)diamine ((CH3)2Si(NH2)2, abbreviated as DMSDA), (diethylsilyl)diamine ((C2H5)2Si(NH2 )2, abbreviation: DESDA), (dipropylsilyl)diamine ((C3H7)2Si(NH2)2, abbreviation: DESDA), bis(dimethylaminodimethylsilyl)methane ([(CH3)2N(CH3)2Si]2CH2, abbreviation: BDMADMSM), bis(dimethylamino)tetramethyldisilane ([(CH3)2N]2(CH3)4Si2, abbreviation: BDMATMDS), etc. can also be used.

[0094] These are all organic compounds having a structure in which an amino group and an alkyl group are directly bonded to Si. These compounds can also be called aminoalkyl compounds or alkylamino compounds. The precursor may be a gaseous substance or a liquid substance. The precursor may also be a liquid substance such as a mist-like substance. One or more of these can be used as the precursor.

[0095] (Step B: Film formation process (selective growth)) Thereafter, the following steps B1 and B2 are executed in sequence. In these steps, the output of the heater 207 is adjusted to maintain the temperature of the wafer 200 at or below the temperature of the wafer 200 in step A, preferably at a temperature lower than the temperature of the wafer 200 in step A.

[0096] [Step B1] In this step, a raw material (raw material gas) and a catalyst (catalyst gas) are supplied as film formation materials to the wafer 200 in the processing chamber 201, i.e., the wafer 200 after a film formation suppression layer has been selectively formed on the surface of the first material (Si).

[0097] Specifically, valves 243b and 243d are opened to allow the raw material to flow into gas supply pipe 232b and the catalyst to flow into gas supply pipe 232d. The raw material and catalyst are adjusted in flow rate by MFCs 241b and 241d, respectively, and are supplied into processing chamber 201 via nozzles 249b and 249a, mixed in processing chamber 201, and exhausted from exhaust port 231a. At this time, the raw material and catalyst are supplied to wafer 200 (raw material + catalyst supply). At this time, valves 243f to 243h may be opened to supply an inert gas into processing chamber 201 via nozzles 249a to 249c, respectively.

[0098] By supplying the raw material and catalyst to the wafer 200 under processing conditions described below, it is possible to selectively (preferentially) chemisorb at least a part of the molecular structure of the molecules constituting the raw material onto the surface of the second material (SiGe) while suppressing chemisorption of at least a part of the molecular structure of the molecules constituting the raw material onto the surface of the first material (Si). As a result, a first layer is selectively (preferentially) formed on the surface of the second material (SiGe). The first layer includes at least a part of the molecular structure of the molecules constituting the raw material. In other words, the first layer includes at least a part of the atoms constituting the raw material.

[0099] In this step, by supplying a catalyst together with the raw material, it becomes possible to carry out the above-mentioned reaction in a non-plasma atmosphere and at a low temperature condition as described later. In this way, by forming the first layer in a non-plasma atmosphere and at a low temperature condition as described later, it becomes possible to maintain the molecules and atoms constituting the film formation suppression layer formed on the surface of the first material (Si) without disappearing (detaching) from the surface of the first material (Si).

[0100] Furthermore, by forming the first layer in a non-plasma atmosphere and under low temperature conditions as described below, the raw material can be prevented from thermally decomposing (vapor phase decomposition), i.e., from self-decomposing, in the processing chamber 201, and multiple deposition of at least a portion of the molecular structure of the molecules constituting the raw material on the surfaces of the first material (Si) and the second material (SiGe) can be suppressed, making it possible to selectively adsorb the raw material onto the surface of the second material (SiGe).

[0101] After the first layer is selectively formed on the surface of the second material (SiGe), the valves 243b and 243d are closed to stop the supply of the raw material and catalyst into the processing chamber 201. Then, gas remaining in the processing chamber 201 is removed (purged) from the processing chamber 201 by the same processing procedure and processing conditions as those for purging in step E. Note that the processing temperature for purging in this step is preferably the same as the processing temperature for supplying the raw material and catalyst.

[0102] The processing conditions for raw material + catalyst supply are as follows: Treatment temperature: room temperature (25°C) to 120°C, preferably room temperature to 90°C Processing pressure: 133~1333Pa Raw material supply flow rate: 1~2000sccm Catalyst supply flow rate: 1~2000sccm Inert gas supply flow rate (per gas supply pipe): 0 to 20,000 sccm Each gas supply time: 1 to 60 seconds Examples include:

[0103] In this step, when forming the first layer, at least a part of the molecular structure of the molecules constituting the raw material may be adsorbed to a part of the surface of the first material (Si), but the amount of adsorption is very small and is much smaller than the amount of at least a part of the molecular structure of the molecules constituting the raw material adsorbed to the surface of the second material (SiGe). Such selective (preferential) adsorption is possible because the processing conditions in this step are low temperature conditions as described above, and are conditions under which the raw material does not undergo gas phase decomposition in the processing chamber 201. Also, this is because the film formation suppression layer is formed over the entire surface of the first material (Si), whereas the film formation suppression layer is not formed in most areas of the surface of the second material (SiGe).

[0104] As the raw material, for example, a gas containing Si and a halogen can be used. The halogen includes chlorine (Cl), fluorine (F), bromine (Br), iodine (I), and the like. The Si- and halogen-containing gas preferably includes a halogen in the form of a chemical bond between Si and a halogen. The Si- and halogen-containing gas may further include C, and in that case, it is preferable to include C in the form of a Si-C bond. As the Si- and halogen-containing gas, for example, a silane-based gas containing Si, Cl, and an alkylene group and having a Si-C bond, that is, an alkylenechlorosilane-based gas, can be used. The alkylene group includes a methylene group, an ethylene group, a propylene group, a butylene group, and the like. The alkylenechlorosilane-based gas preferably includes Cl in the form of a Si-Cl bond and C in the form of a Si-C bond.

[0105] Examples of the Si- and halogen-containing gas include alkylene chlorosilane gases such as bis(trichlorosilyl)methane ((SiCl3)2CH2, abbreviated as BTCSM) gas and 1,2-bis(trichlorosilyl)ethane ((SiCl3)2C2H4, abbreviated as BTCSE) gas; alkyl chlorosilane gases such as 1,1,2,2-tetrachloro-1,2-dimethyldisilane ((CH3)2Si2Cl4, abbreviated as TCDMDS) gas and 1,2-dichloro-1,1,2,2-tetramethyldisilane ((CH3)4Si2Cl2, abbreviated as DCTMDS) gas; and gases containing a cyclic structure composed of Si and C and halogens, such as 1,1,3,3-tetrachloro-1,3-disilacyclobutane (C2H4Cl4Si2, abbreviated as TCDSCB) gas. In addition, as the Si- and halogen-containing gas, inorganic chlorosilane-based gases such as tetrachlorosilane (SiCl4, abbreviated as STC) gas, hexachlorodisilane (Si2Cl6, abbreviated as HCDS) gas, and octachlorotrisilane (Si3Cl8, abbreviated as OCTS) gas can also be used. As the raw material, one or more of these can be used. The raw material may be a gaseous substance or a liquid substance. The raw material may also be a liquid substance such as a mist-like substance.

[0106] Also, instead of the Si- and halogen-containing gas, aminosilane-based gases such as tetrakis(dimethylamino)silane (Si[N(CH3)2]4, abbreviated as 4DMAS) gas, tris(dimethylamino)silane (Si[N(CH3)2]3H, abbreviated as 3DMAS) gas, bis(diethylamino)silane (Si[N(C2H5)2]2H2, abbreviated as BDEAS) gas, bis(tertiarybutylamino)silane (SiH2[NH(C4H9)]2, abbreviated as BTBAS) gas, and (diisopropylamino)silane (SiH3[N(C3H7)2], abbreviated as DIPAS) gas can be used as the raw material. One or more of these can be used as the raw material.

[0107] As the catalyst, for example, the same catalysts as those exemplified in step C above can be used.

[0108] [Step B2] After step B1 is completed, an oxidant (oxidizing gas) and a catalyst (catalytic gas) are supplied as film forming materials to the wafer 200 in the processing chamber 201, i.e., the wafer 200 after the first layer has been selectively formed on the surface of the second material (SiGe).

[0109] Specifically, the valves 243c and 243d are opened to allow an oxidant to flow into the gas supply pipe 232c and a catalyst to flow into the gas supply pipe 232d. The oxidant and catalyst are adjusted in flow rate by the MFCs 241c and 241d, respectively, and are supplied into the processing chamber 201 via the nozzles 249c and 249a, mixed in the processing chamber 201, and exhausted from the exhaust port 231a. At this time, the oxidant and catalyst are supplied to the wafer 200 (oxidant + catalyst supply). At this time, the valves 243f to 243h may be opened to supply an inert gas into the processing chamber 201 via the nozzles 249a to 249c, respectively.

[0110] By supplying an oxidizing agent and a catalyst to the wafer 200 under processing conditions described below, it becomes possible to oxidize at least a part of the first layer formed on the surface of the second material (SiGe) in step B1. As a result, a second layer, which is the oxidized first layer, is formed on the surface of the second material (SiGe).

[0111] In this step, by supplying a catalyst together with an oxidizing agent, it becomes possible to allow the above-mentioned reaction to proceed in a non-plasma atmosphere and at a low temperature condition as described later. In this way, by forming the second layer in a non-plasma atmosphere and at a low temperature condition as described later, it becomes possible to maintain the molecules and atoms constituting the film-formation suppression layer formed on the surface of the first material (Si) without disappearing (detaching) from the surface of the first material (Si).

[0112] After the first layer formed on the surface of the second material (SiGe) is oxidized and changed (converted) into the second layer, the valves 243c and 243d are closed to stop the supply of the oxidant and catalyst into the processing chamber 201. Then, gases remaining in the processing chamber 201 are removed (purged) from the processing chamber 201 by the same processing procedure and processing conditions as those for purging in step E. Note that the processing temperature for purging in this step is preferably the same as the processing temperature for supplying the oxidant and catalyst.

[0113] The treatment conditions for oxidant + catalyst supply are as follows: Treatment temperature: room temperature (25°C) to 120°C, preferably room temperature to 100°C Processing pressure: 133~1333Pa Oxidant supply flow rate: 1 to 2000 sccm Catalyst supply flow rate: 1~2000sccm Inert gas supply flow rate (per gas supply pipe): 0 to 20,000 sccm Each gas supply time: 1 to 60 seconds Examples include:

[0114] The oxidizing agent may be, for example, the same oxidizing agent as the various oxidizing agents exemplified in the above-mentioned step C. The catalyst may be, for example, the same catalyst as the various catalysts exemplified in the above-mentioned step C.

[0115] [Perform the specified number of times] By performing the above-mentioned steps B1 and B2 a predetermined number of times (n times, n being an integer of 1 or more) of cycles in which they are performed asynchronously, that is, not simultaneously, as shown in FIG. 5(b), a film can be selectively (preferentially) grown on the surface of the second material (SiGe) of the first material (Si) and the second material (SiGe) in the recesses on the surface of the wafer 200. For example, when the above-mentioned raw material, oxidizing agent, and catalyst are used, a SiOC film or a SiO film can be selectively grown as a film on the surface of the second material (SiGe). It is preferable to repeat the above-mentioned cycle multiple times. That is, it is preferable to make the thickness of the second layer formed per cycle thinner than the desired film thickness, and to repeat the above-mentioned cycle multiple times until the film formed by stacking the second layers has the desired film thickness.

[0116] By repeating the above cycle multiple times, a film can be grown from the surface of the second material (SiGe) constituting the bottom of the recess on the surface of the wafer 200 toward the opening of the recess. At this time, since a film formation suppressing layer is formed on the surface of the first material (Si) constituting the upper and side surfaces of the recess, the growth of the film starting from the surface of the first material (Si) can be suppressed. In other words, by repeating the above cycle multiple times, the growth of the film starting from the bottom surface of the recess can be promoted while suppressing the growth of the film starting from the upper and side surfaces of the recess, and the film can be grown bottom-up in the recess, making it possible to fill the recess with a film (SiOC) as shown in FIG. 5(c).

[0117] In addition, when steps B1 and B2 are performed, as shown in FIG. 5(b) and FIG. 5(c), the film-formation suppressing layer formed on the surface of the first material (Si) is maintained on the surface of the first material (Si) as described above, so that the growth of the film originating from the surface of the first material (Si) can be suppressed. However, in cases where the formation of the film-formation suppressing layer on the surface of the first material (Si) is insufficient due to some factor, the growth of the film originating from the surface of the first material (Si) may occur very slightly. However, even in this case, the thickness of the film formed originating from the surface of the first material (Si) is much thinner than the thickness of the film formed originating from the surface of the second material (SiGe). Therefore, even in such a case, the recess can be appropriately filled by the bottom-up growth described above.

[0118] (Step F:PT) After the film formation process is completed, the wafer 200 is heated and heat-treated to perform a post-treatment (PT) on the film formed to fill the recess. At this time, the output of the heater 207 is adjusted so that the temperature in the process chamber 201, i.e., the temperature of the wafer 200 after the film is formed to fill the recess, is equal to or higher than the temperature of the wafer 200 in step A or step B, preferably higher than the temperature of the wafer 200 in step A or step B. By performing PT, it is possible to remove impurities contained in the film formed to fill the recess and repair defects. In addition, as shown in FIG. 5(d), PT can remove residues or residues of the film formation suppressing layer on the surface of the first material (Si), i.e., the upper surface of the recess and the interface between the side surface of the recess and the film (SiOC). This step may be performed in a state where an inert gas is supplied into the process chamber 201, or in a state where a reactive substance such as an oxidizing agent (oxidizing gas) is supplied. When a reactive substance such as an oxidizing agent is supplied, it is possible to enhance the effect of removing residues or remnants of the film-formation-suppressing layer on the upper surface of the recess or on the interface between the side surface of the recess and the film. In this case, the reactive substance such as an inert gas or an oxidizing agent (oxidizing gas) is also called an assist substance.

[0119] The post-treatment (PT) treatment conditions are as follows: Treatment temperature: 120 to 1000°C, preferably 400 to 700°C Processing pressure: 1~120000Pa Processing time: 1 to 18,000 seconds Assist material supply flow rate: 0 to 50 slm Examples include:

[0120] (After purging and atmospheric pressure recovery) After the film formation process is finished and PT is completed, an inert gas is supplied as a purge gas from each of the nozzles 249a to 249c into the processing chamber 201 and exhausted from the exhaust port 231a. This purges the processing chamber 201, and gas and reaction by-products remaining in the processing chamber 201 are removed from the processing chamber 201 (after-purge). Thereafter, the atmosphere in the processing chamber 201 is replaced with the inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure (return to atmospheric pressure).

[0121] (Boat unloading and wafer discharging) Thereafter, the seal cap 219 is lowered by the boat elevator 115, and the lower end of the manifold 209 is opened. Then, the processed wafers 200 are carried out from the lower end of the manifold 209 to the outside of the reaction tube 203 while being supported by the boat 217 (boat unloading). After the boat unloading, the shutter 219s is moved, and the lower end opening of the manifold 209 is sealed by the shutter 219s via the O-ring 220c (shutter close). After being carried out to the outside of the reaction tube 203, the processed wafers 200 are taken out of the boat 217 (wafer discharge).

[0122] (3) Effects of this mode According to this aspect, one or more of the following effects can be obtained.

[0123] (a) Step A of supplying a precursor to the wafer 200 and forming a film-formation suppressing layer on the surface of the first material (Si) in the recess on the surface of the wafer 200, and step B of supplying a film-formation substance to the wafer 200 on which the film-formation suppressing layer has been formed on the surface of the first material and growing a film on the surface of the second material (SiGe) in the recess can be performed, thereby suppressing the growth of a film originating from the top and side surfaces of the recess and promoting the growth of a film originating from the bottom surface of the recess. This allows the film to grow bottom-up in the recess, and makes it possible to fill the recess with the film without generating voids or seams in the film. In other words, it becomes possible to form a void-free and seamless film in the recess, and improve the filling characteristics.

[0124] (b) By suppressing the growth of the film originating from the top and side surfaces of the recess, while promoting the growth of the film originating from the bottom surface of the recess, the recess can be filled with the film without growing the film on the top surface of the recess. As a result, as shown in FIG. 5(c), a state can be created in which the film (SiOC) is not formed on the top surface of the recess when the film formation process is completed. That is, when the film formation process is completed, the inside of the recess on the side wall of the layered structure formed by alternately stacking the second material (SiGe) and the first material (Si) on the surface of the wafer 200 can be filled with the film (SiOC) and the side wall can be made flat. This makes it possible to omit the step of removing the excess film formed on the top surface of the recess by etching after the film formation process, which was previously required.

[0125] As described above, even if a film formation suppression layer is formed on the surface of the first material, a film may grow very slightly starting from the surface of the first material due to some factor. In this case, a process of etching the excess film formed on the upper surface of the recess may be required. However, even in this case, the excess film formed on the upper surface of the recess is very small as described above, and it is possible to significantly reduce the load in the process of etching the excess film and significantly shorten the time required for etching.

[0126] On the other hand, when the inside of the recess is filled with a film such as a SiOC film by a conventional film forming method in which only step B is performed, as shown in FIG. 6(b), a film (SiOC) is formed on the entire side wall of the layered structure in which the second material (SiGe) and the first material (Si) are alternately stacked on the surface of the wafer 200. At that time, as shown in FIG. 6(b), voids or seams (hereinafter, voids) may be formed in the film due to the shape of the recess. In this case, in order to fill the inside of the recess on the side wall of the layered structure in which the second material and the first material are alternately stacked with a film and make the side wall flat, it is necessary to perform a process of etching the excess film formed on the upper surface of the recess. For example, when a process of etching the excess film formed on the upper surface of the recess is performed on a substrate having the configuration in FIG. 6(b) on the surface, a state in which no film is formed on the upper surface of the recess can be created as shown in FIG. 6(c). However, in this case, as shown in Fig. 6(c), the voids formed in the film during film formation remain, and in some cases the voids become deeper due to etching, making it impossible to flatten the sidewalls of the layered structure in which the second material and the first material are alternately layered. In addition, when using a conventional film formation method, it is necessary to perform a process of etching the excess film, which lengthens the total processing time and reduces productivity.

[0127] In contrast, according to the present embodiment, a void-free and seamless film can be formed in the recess while suppressing the growth of the film on the upper surface of the recess. Furthermore, when the film formation process is completed, the inside of the recess at the sidewall of the laminated structure in which the second material (SiGe) and the first material (Si) are alternately laminated can be filled with a film (SiOC), and the sidewall can be made flat. This makes it possible to omit the process of removing the excess film formed on the upper surface of the recess by etching, which was essential in the conventional film formation method after the film formation process. Even if the growth of the film originating from the surface of the first material occurs very slightly due to some factor despite the formation of a film formation suppression layer on the surface of the first material, the excess film formed on the upper surface of the recess is very small, and it is possible to significantly reduce the load in the process of etching the excess film and significantly shorten the time required for etching. That is, according to the present embodiment, void-free and seamless filling is possible, and not only can the filling characteristics be improved, but also the total processing time can be shortened by omitting the step of etching away excess film or reducing the load of the step of etching away excess film, thereby making it possible to improve productivity.

[0128] (c) By forming OH termination on the surface of the first material in the recesses on the surface of the wafer 200 before performing step A, it is possible to promote the adsorption of at least a part of the molecular structure of the molecules constituting the precursor to the surface of the first material in the recesses, and it is possible to properly form a film formation suppression layer on the surface of the first material. In this case, by making the amount (density, concentration) of OH termination on the surface of the first material (Si) greater (higher) than the amount (density, concentration) of OH termination on the surface of the second material (SiGe) before performing step A, it is possible to selectively (preferentially) adsorb at least a part of the molecular structure of the molecules constituting the precursor to the surface of the first material out of the first material and the second material in the recesses, and to selectively (preferentially) form a film formation suppression layer on the surface of the first material. It is also possible to form a state in which OH termination is not formed on the surface of the second material before performing step A, in which case it is possible to increase the selectivity in selective adsorption of at least a part of the molecular structure of the molecules constituting the precursor to the surface of the first material and selective formation of the film formation suppression layer on the surface of the first material.

[0129] (d) By performing step C of forming OH termination on the surface of the first material in the recesses on the surface of the wafer 200 before performing step A, it is possible to promote the adsorption of at least a part of the molecular structure of the molecules constituting the precursor to the surface of the first material in the recesses, and it is possible to properly form a film formation suppression layer on the surface of the first material. In step C, for example, an oxidizing agent is supplied to the wafer 200 as a reactant to oxidize the surface of the first material, so that it is possible to efficiently and controllably form OH termination on the surface of the first material. In this case, in step C, OH termination is also formed on the surface of the second material, but by performing step D of removing the OH termination formed on the surface of the second material after performing step C and before performing step A, it is possible to create a state in which OH termination is not formed on the surface of the second material. Note that in step D, by heating and annealing the wafer 200, it is possible to selectively sublimate and remove oxides such as GeO formed on the surface of the second material (SiGe) while leaving (maintaining) an oxide film such as SiO formed on the surface of the first material (Si). That is, in step D, by simply heating the wafer 200, the OH termination formed on the surface of the second material (SiGe) can be selectively removed while leaving (maintaining) the OH termination formed on the surface of the first material (Si).

[0130] This allows the amount (density, concentration) of OH terminations on the surface of the first material (Si) before step A to be greater (higher) than the amount (density, concentration) of OH terminations on the surface of the second material (SiGe), and at least a part of the molecular structure of the precursor is selectively (preferentially) adsorbed on the surface of the first material out of the first and second materials in the recess, thereby selectively (preferentially) forming a film formation suppressing layer on the surface of the first material. Note that by performing the annealing in step D sufficiently, it is possible to make the surface of the second material before step A a state in which no OH termination is formed, and in that case, it is possible to increase the selectivity in selective adsorption of at least a part of the molecular structure of the precursor to the surface of the first material and selective formation of the film formation suppressing layer on the surface of the first material.

[0131] (e) Before performing step C, step E is performed to remove the natural oxide film on the surfaces of the first material and the second material in the recesses on the surface of the wafer 200, thereby removing the oxide film that may be formed unevenly on the surfaces of the first material and the second material, and thereby removing the OH termination that may be formed unevenly on the surfaces of the first material and the second material. Then, step C is performed to uniformly oxidize the surface of the first material, and a uniform oxide film can be formed on the surface of the first material. As a result, the OH termination can be uniformly formed on the surface of the first material. This allows at least a part of the molecular structure of the molecules constituting the precursor to be more uniformly adsorbed on the surface of the first material in the recesses in step A, making it possible to more uniformly form a film formation suppression layer on the surface of the first material.

[0132] (f) After step B is completed, the temperature of the wafer 200 is set to be equal to or higher than the temperature of the wafer 200 in step A or step B, preferably higher than the temperature of the wafer 200 in step A or step B, and post-treatment (PT) is performed on the film formed to fill the recesses, thereby removing impurities contained in the film formed to fill the recesses and repairing defects. Furthermore, residues and residues of the film-formation suppressing layer on the surface of the first material, i.e., the upper surface of the recesses and the interface between the side surface of the recesses and the film, can be desorbed. At this time, the process may be performed in a state where an inert gas is supplied into the process chamber 201, or in a state where a reactive substance such as an oxidizing agent (oxidizing gas) is supplied. When a reactive substance such as an oxidizing agent is supplied, it is possible to enhance the effect of desorbing residues and residues of the film-formation suppressing layer on the upper surface of the recesses and the interface between the side surface of the recesses and the film.

[0133] (g) Each reaction in each step can be carried out in a non-plasma atmosphere, and excessive reactions in each step can be suppressed, improving the controllability of the reaction. In addition, since each step is carried out in a non-plasma atmosphere, plasma damage to the wafer 200 can be avoided, and the method can be applied to processes where plasma damage is a concern.

[0134] (4) Variations The substrate processing sequence in this embodiment can be modified as shown in the following modified examples. These modified examples can be combined as desired. Unless otherwise specified, the process procedure and process conditions in each step of each modified example can be the same as the process procedure and process conditions in each step of the substrate processing sequence described above.

[0135] (Variation 1) As in the processing sequence shown below, depending on the surface state of the wafer 200, step E (removal of native oxide film) may be omitted. For example, after forming a layered structure in which the second material (SiGe) and the first material (Si) in FIG. 5(a) are alternately layered on the surface of the wafer 200, the surface of the wafer 200 may be in an appropriate surface state when the surface of the wafer 200 is not exposed to the atmosphere, the amount of exposure to the atmosphere is small, or the time of exposure to the atmosphere is short. In such a case, step E can be omitted, and the processing sequence can be started from step C (oxidation). In this modified example, the same effect as the above-mentioned embodiment can be obtained. Furthermore, by omitting step E, the total processing time can be shortened, and productivity can be improved.

[0136] Oxidant → ANL → precursor → (raw material + catalyst → oxidant + catalyst) × n → PT

[0137] (Variation 2) As shown in the processing sequence below, depending on the surface condition of the wafer 200, step E (removal of native oxide film) and step C (oxidation) may be omitted. For example, when an oxide film is uniformly formed on the surfaces of the first material (Si) and the second material (SiGe) on the surface of the wafer 200, steps E and C can be omitted, and the processing sequence can start from step D (ANL). In this modified example, the same effect as the above-mentioned embodiment can be obtained. Moreover, by omitting steps E and C, the total processing time can be shortened, and productivity can be improved.

[0138] ANL → precursor → (raw material + catalyst → oxidant + catalyst) × n → PT

[0139] (Variation 3) As shown in the processing sequence below, depending on the surface state of the wafer 200, step E (removal of natural oxide film), step C (oxidation), and step D (ANL) may be omitted. For example, when an oxide film is uniformly formed on the surfaces of the first material and the second material on the surface of the wafer 200, and in step A (film formation suppression layer formation), the wafer 200 is heated to a temperature of, for example, 100° C. or higher, in step A, an oxide film such as a SiO film formed on the surface of the first material is left (maintained), and an oxide such as GeO formed on the surface of the second material can be sublimated and removed. That is, in step A, an OH termination formed on the surface of the second material can be removed while an OH termination formed on the surface of the first material is left (maintained). In this case, steps E, C, and D can be omitted, and the processing sequence can be started from step A. In this modified example, the same effect as the above-mentioned embodiment can be obtained. In addition, by omitting steps E, C, and D, the total processing time can be shortened, and productivity can be improved.

[0140] Precursor → (raw material + catalyst → oxidant + catalyst) × n → PT

[0141] (Variation 4) As shown in the process sequence below, in step B1, the raw material may be supplied alone to the wafer 200 without supplying a catalyst. In addition, in step B2, the oxidizing agent may be supplied alone to the wafer 200 without supplying a catalyst. By supplying the raw material and the catalyst to the wafer 200, the chemical adsorption of at least a part of the molecular structure of the molecules constituting the raw material to the surface of the second material can be promoted at low temperatures. In addition, by supplying the oxidizing agent and the catalyst to the wafer 200, the oxidation rate can be increased at low temperatures. However, in cases where the chemical adsorption of at least a part of the molecular structure of the molecules constituting the raw material to the surface of the second material or the oxidation rate is adjusted by temperature, the supply of the catalyst can be omitted. In this modified example, the same effects as those of the above-mentioned embodiment can be obtained.

[0142] Etching agent → Oxidizing agent → ANL → Precursor → (raw material → Oxidizing agent + catalyst) × n → PT Etching agent → Oxidizing agent → ANL → Precursor → (raw material + catalyst → Oxidizing agent) × n → PT Etching agent → Oxidizing agent → ANL → Precursor → (raw material → Oxidizing agent) × n → PT

[0143] (Variation 5) Step F (PT) may be omitted as in the process sequence shown below. For example, step F may be omitted if the amount of impurities contained in the film formed to fill the recess is within an allowable range. Step F may also be omitted if the film-formation suppressing layer is allowed to remain on the upper surface of the recess or on the interface between the side surface of the recess and the film, or if the amount of residues or remnants of the film-formation suppressing layer on the upper surface of the recess or on the interface between the side surface of the recess and the film is within an allowable range. Step F may also be omitted if the film-formation suppressing layer on the upper surface of the recess or on the interface between the side surface of the recess and the film is removed by reaction in each step of the film-formation process. This modified example also provides the same effects as the above-mentioned embodiment. By omitting step F, the total processing time can be shortened, and productivity can be improved.

[0144] Etching agent → Oxidizing agent → ANL → Precursor → (raw material + catalyst → Oxidizing agent + catalyst) × n

[0145] <Other Aspects of the Disclosure> Although the embodiments of the present disclosure have been specifically described above, the present disclosure is not limited to the above embodiments and can be modified in various ways without departing from the spirit and scope of the present disclosure.

[0146] For example, in step E, an etching agent may be plasma-excited and supplied to the wafer 200. This can increase the etching rate when etching the native oxide film. In addition, in step C, a reactive material such as an oxidizer may be plasma-excited and supplied to the wafer 200. This can increase the oxidation rate. In addition, in step D, an inert gas may be plasma-excited and supplied. This makes it possible to remove oxides such as GeO formed on the surface of the second material by sublimation and to treat the surface of the second material after the oxides have been removed. In addition, in step D, an assist material may be plasma-excited and supplied. This can further increase the effect of removing residues and residues of the film-formation suppressing layer on the upper surface of the recess and on the interface between the side surface of the recess and the film.

[0147] Also, for example, in step B, not only a SiOC film or a SiO film but also a silicon oxide film such as a silicon oxycarbonitride film (SiOCN film), a silicon oxynitride film (SiON film), a silicon boron oxynitride film (SiBON film), a silicon boron oxycarbonitride film (SiBOCN film), etc. may be formed. Also, in step B, a metal oxide film such as an aluminum oxide film (AlO film), a titanium oxide film (TiO film), a hafnium oxide film (HfO film), a zirconium oxide film (ZrO film), etc. may be formed.

[0148] It is preferable that the recipes used for each process are prepared individually according to the process contents and stored in the storage device 121c via an electric communication line or an external storage device 123. Then, when starting each process, it is preferable that the CPU 121a appropriately selects an appropriate recipe according to the process contents from among the multiple recipes stored in the storage device 121c. This makes it possible to form films of various film types, composition ratios, film qualities, and film thicknesses with good reproducibility using a single substrate processing device. It is also possible to reduce the burden on the operator and quickly start each process while avoiding operational errors.

[0149] The above-mentioned recipes may not only be newly created, but may also be prepared by modifying an existing recipe that has already been installed in the substrate processing apparatus. When modifying a recipe, the modified recipe may be installed in the substrate processing apparatus via an electric communication line or a recording medium on which the recipe has been recorded. In addition, an existing recipe that has already been installed in the substrate processing apparatus may be directly modified by operating the input / output device 122 provided in the existing substrate processing apparatus.

[0150] In the above-mentioned embodiment, an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at a time has been described. The present disclosure is not limited to the above-mentioned embodiment, and can be suitably applied to, for example, a case where a film is formed using a single-wafer type substrate processing apparatus that processes one or several substrates at a time. Also, in the above-mentioned embodiment, an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace has been described. The present disclosure is not limited to the above-mentioned embodiment, and can be suitably applied to, for example, a case where a film is formed using a substrate processing apparatus having a cold-wall type processing furnace.

[0151] When using these substrate processing apparatuses, each process can be performed under the same process procedures and conditions as in the above embodiment, and the same effects as in the above embodiment can be obtained.

[0152] The above-mentioned aspects may be used in appropriate combination. The processing procedures and processing conditions in this case may be the same as those of the above-mentioned aspects. EXAMPLES

[0153] Using the above-mentioned substrate processing apparatus, a wafer having a layered structure in which SiGe films and Si films are alternately stacked on the surface as shown in Fig. 5(a), with the top and side surfaces being composed of Si films and the bottom surface being composed of a SiGe film, and having a recess with a depth direction parallel to the surface of the wafer (horizontal direction), was subjected to the above-mentioned processing sequence to form a SiOC film so as to fill the recess, thereby producing evaluation sample 1. Thereafter, a cross-sectional TEM image of evaluation sample 1 was taken. A cross-sectional TEM image of evaluation sample 1 is shown in Fig. 7.

[0154] Using the above-mentioned substrate processing apparatus, a wafer having the same configuration as the wafer used to fabricate evaluation sample 1 was subjected to the processing sequence of the above-mentioned modified example 3 to form a SiOC film so as to fill the recesses, thereby fabricating evaluation sample 2. Thereafter, a cross-sectional TEM image of evaluation sample 2 was taken. The cross-sectional TEM image of evaluation sample 2 is shown in FIG. 8.

[0155] As shown in Fig. 7, in evaluation sample 1, the SiOC film is selectively formed only inside the recess, without being formed on the upper surface of the recess. It is also found that no voids or seams are generated in the SiOC film formed in the recess. It is also found that by controlling (increasing) the number of cycles in step B when producing evaluation sample 1, it is possible to suppress the growth of the SiOC film on the upper surface of the recess and to selectively grow the SiOC film further inside the recess, and it is possible to fill the inside of the recess on the side wall of the layered structure in which the SiGe film and the Si film are alternately layered with the SiOC film and make the side wall flat.

[0156] As shown in FIG. 8, in the evaluation sample 2, a void-free and seamless SiOC film is formed to fill the recess. In the evaluation sample 2, although a small amount of the SiOC film is formed on the upper surface of the recess, the SiOC film has a flat profile on the sidewall of the laminated structure in which the SiGe film and the Si film are alternately laminated. In this case, the SiOC film formed on the sidewall of the laminated structure in which the SiGe film and the Si film are alternately laminated is etched by the thickness of the SiOC film formed on the upper surface of the recess, so that the sidewall of the laminated structure is kept flat while the Si film on the sidewall, i.e., the upper surface (Si) of the recess, can be exposed. In the preparation of the evaluation sample 2, the number of cycles in step B is controlled (reduced) to stop the deposition at the point when the recess is filled with the SiOC film, so that the sidewall of the laminated structure in which the SiGe film and the Si film are alternately laminated can be made flat without forming a SiOC film on the upper surface of the recess. [Explanation of symbols]

[0157] 200 wafers (substrates)

Claims

1. (a) supplying a precursor to a substrate having a surface on which a recess is provided, the surface being made of a first material containing a first element and a second material containing a second element different from the first element, thereby adsorbing at least a part of a molecular structure of a molecule constituting the precursor to a surface of the first material in the recess, thereby forming an inhibitor layer on the surface of the first material; (b) supplying a film-forming substance to the substrate on which the inhibitor layer is formed on the surface of the first material, thereby growing a film on the surface of the second material in the recess; (c) before carrying out (a), a step of forming a hydroxyl group termination on a surface of the first material and a surface of the second material; (d) removing the hydroxyl group termination formed on the surface of the second material before carrying out (a); The processing method according to claim 1,

2. 2. The method of claim 1, further comprising the step of: (e) removing native oxide films on the surfaces of the first material and the second material before performing (c).

3. 3. The method according to claim 1, wherein the amount of hydroxyl group terminations on the surface of the first material before (a) is performed is greater than the amount of hydroxyl group terminations on the surface of the second material before (a) is performed.

4. The method according to claim 1 or 2, wherein no hydroxyl group is terminated on the surface of the second material before (a) is performed.

5. The method according to any one of claims 1 to 4, wherein (c) comprises supplying a reactive material to the substrate to oxidize the surface of the first material and the surface of the second material to form hydroxyl group terminations on the surface of the first material and the surface of the second material.

6. The method according to any one of claims 1 to 5, wherein in step (d), the substrate is heated to sublimate the oxide formed on the surface of the second material, thereby removing the hydroxyl group termination formed on the surface of the second material.

7. The method according to any one of claims 1 to 6, wherein in (d), the hydroxyl group terminations formed on the surface of the second material are removed while leaving the hydroxyl group terminations formed on the surface of the first material.

8. The method according to any one of claims 1 to 7, wherein the recess has a bottom surface made of the second material.

9. The method according to any one of claims 1 to 8, wherein the recess includes a side surface made of the first material.

10. The method according to any one of claims 1 to 9, wherein the recess includes an upper surface made of the first material.

11. The method according to any one of claims 1 to 10, wherein in (b), a film is grown on a surface of the second material in the recess, thereby growing the film bottom-up within the recess, and filling the recess with the film.

12. In (b), (b1) supplying a raw material as the film forming material to the substrate; (b2) supplying a reactant to the substrate as the deposition material; The method according to any one of claims 1 to 11, further comprising performing a cycle including the steps of:

13. The processing method according to claim 12 , wherein in at least one of (b1) and (b2), a catalyst is further supplied to the substrate as the film forming material.

14. The method according to any one of claims 1 to 13, wherein the second material further contains the first element.

15. The method according to any one of claims 1 to 14, wherein the first element is silicon and the second element is germanium.

16. The method of any one of claims 1 to 15, wherein the first material is silicon and the second material is silicon germanium.

17. The method according to any one of claims 1 to 16, wherein in (b), a film containing silicon, oxygen, and carbon is grown as the film.

18. (a) supplying a precursor to a substrate having a surface on which a recess is provided, the surface being made of a first material containing a first element and a second material containing a second element different from the first element, thereby adsorbing at least a part of a molecular structure of a molecule constituting the precursor to a surface of the first material in the recess, thereby forming an inhibitor layer on the surface of the first material; (b) supplying a film-forming substance to the substrate on which the inhibitor layer is formed on the surface of the first material, thereby growing a film on the surface of the second material in the recess; (c) before carrying out (a), a step of forming a hydroxyl group termination on a surface of the first material and a surface of the second material; (d) removing the hydroxyl group termination formed on the surface of the second material before carrying out (a); A method for manufacturing a semiconductor device having the above structure.

19. a precursor delivery system for delivering a precursor to the substrate; a deposition material supply system for supplying a deposition material to the substrate; a reactant supply system for supplying reactants to the substrate; A heater for heating the substrate; (a) supplying the precursor to a substrate having a recess on its surface, the recess being made of a first material containing a first element and a second material containing a second element different from the first element, thereby adsorbing at least a part of a molecular structure of a molecule constituting the precursor to a surface of the first material in the recess, thereby forming an inhibitor layer on the surface of the first material; (b) supplying the film-forming substance to the substrate on which the inhibitor layer is formed on the surface of the first material, thereby growing a film on the surface of the second material in the recess; (c) before carrying out (a), supplying the reactant to the substrate to form a hydroxyl group termination on a surface of the first material and a surface of the second material; (d) before carrying out (a), a treatment of heating the substrate to remove the hydroxyl group termination formed on the surface of the second material; a control unit configured to be able to control the precursor supply system, the deposition material supply system, the reactant supply system, and the heater so as to perform the above-mentioned A processing device having

20. (a) supplying a precursor to a substrate having a surface on which a recess is provided, the surface being made of a first material containing a first element and a second material containing a second element different from the first element, thereby adsorbing at least a part of a molecular structure of a molecule constituting the precursor to a surface of the first material in the recess, thereby forming an inhibitor layer on the surface of the first material; (b) supplying a film-forming substance to the substrate on which the inhibitor layer is formed on the surface of the first material, thereby growing a film on the surface of the second material in the recess; (c) before carrying out (a), a step of forming a hydroxyl group termination on a surface of the first material and a surface of the second material; (d) before carrying out (a), removing the hydroxyl group termination formed on the surface of the second material; A program that causes a processing device to execute the above by a computer.

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