Substrate processing method, semiconductor device manufacturing method, program, and substrate processing device

Abstract

The present invention has (a) a step for supplying a first gas containing a group 14 element and forming a first film containing the group 14 element contained in the first gas preferentially on a group 14 element exposed surface on the bottom side of a recess of a substrate, (b) a step for supplying a second gas containing a group 14 element and forming, in the recess of the substrate, a second film containing the group 14 element contained in the second gas, (c) a step for supplying a third gas containing a second halogen element and etching a portion of the second film, and (d) a step for removing, after (c), the second halogen element remaining on the substrate.

Description

Substrate processing method, semiconductor device manufacturing method, program, and substrate processing apparatus.

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

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

[0003] Japanese Patent Publication No. 2010-118462

[0004] This disclosure provides a technology that can improve the film quality of a film formed on a substrate.

[0005] According to one aspect of the present disclosure, a technique is provided comprising: (a) supplying a first gas containing a group 14 element to form a first film containing the group 14 element preferentially on the group 14 element exposed surface at the bottom of a recess in a substrate; (b) supplying a second gas containing a group 14 element to form a second film containing the group 14 element in the recess of the substrate; (c) supplying a third gas containing a second halogen element to etch a portion of the second film; and (d) removing the second halogen element remaining on the substrate after (c).

[0006] According to this disclosure, the film quality of the film formed on the substrate can be improved.

[0007] Figure 1 is a schematic diagram of the vertical processing furnace of a substrate processing apparatus according to one embodiment of the present disclosure, showing the processing furnace 202 portion in a vertical cross-sectional view. Figure 2 is a schematic diagram of a part of the vertical processing furnace of a substrate processing apparatus according to one embodiment of the present disclosure, showing the processing furnace 202 portion in a cross-sectional view along line A-A in Figure 1. Figure 3 is a schematic diagram of the control unit of a substrate processing apparatus according to one embodiment of the present disclosure, showing the control system in a block diagram. Figure 4 is a diagram showing an example of a flowchart of a substrate processing step according to one embodiment of the present disclosure. Figure 5(a) is an enlarged cross-sectional view of a portion of the substrate in one embodiment of the present disclosure before step A is performed. Figure 5(b) is an enlarged cross-sectional view of a portion of the substrate in one embodiment of the present disclosure after step A is performed. Figure 5(c) is an enlarged cross-sectional view of a portion of the substrate in one embodiment of the present disclosure after step B is performed. Figure 5(d) is an enlarged cross-sectional view of a portion of the substrate in one embodiment of the present disclosure after step C is performed. Figure 5(e) is a partially enlarged cross-sectional view of a substrate in one embodiment of the present disclosure after step D has been performed in the first cycle, when steps D, B, and C are performed in that order a predetermined number of times after step C has been performed. Figure 5(f) is a partially enlarged cross-sectional view of a substrate in one embodiment of the present disclosure after step B has been performed in the first cycle, when steps D, B, and C are performed in that order a predetermined number of times after step C has been performed. Figure 5(g) is a partially enlarged cross-sectional view of a substrate in one embodiment of the present disclosure after step C has been performed in the first cycle, when steps D, B, and C are performed in that order a predetermined number of times after step C has been performed. Figure 5(h) is a partially enlarged cross-sectional view of a substrate in one embodiment of the present disclosure after steps D, B, and C have been performed in that order a predetermined number of times after step C has been performed. Figure 6(a) is a partially enlarged cross-sectional view of a substrate in one embodiment of the present disclosure before step A has been performed, showing an example where a native oxide film 200f is formed on the bottom of the substrate. Figure 6(b) is a partially enlarged cross-sectional view of a substrate in one embodiment of the present disclosure after step E has been performed, before step A has been performed. Figure 6(c) is a partially enlarged cross-sectional view of a substrate in one embodiment of the present disclosure after step E has been performed and step F has been performed. Figure 6(d) is a partially enlarged cross-sectional view of a substrate in one embodiment of the present disclosure after step E has been performed, when the native oxide film 200f and adsorption inhibitors 200g have been removed in advance before step A has been performed.FIG. 7(a) is an enlarged partial cross-sectional view of a substrate in Modification 1 of the present disclosure before performing Step A. FIG. 7(b) is an enlarged partial cross-sectional view of the substrate in Modification 1 of the present disclosure after performing Step A. FIG. 7(c) is an enlarged partial cross-sectional view of the substrate in Modification 1 of the present disclosure after performing Step B. FIG. 7(d) is an enlarged partial cross-sectional view of the substrate in Modification 1 of the present disclosure after performing Step C. FIG. 7(e) is an enlarged partial cross-sectional view of the substrate in Modification 1 of the present disclosure after performing Step D in the first cycle when Steps D, B, and C are performed a predetermined number of times in this order after the execution of Step C. FIG. 7(f) is an enlarged partial cross-sectional view of the substrate in Modification 1 of the present disclosure after performing Step B in the first cycle when Steps D, B, and C are performed a predetermined number of times in this order after the execution of Step C. FIG. 7(g) is an enlarged partial cross-sectional view of the substrate in Modification 1 of the present disclosure after performing Step C in the first cycle when Steps D, B, and C are performed a predetermined number of times in this order after the execution of Step C. FIG. 7(h) is an enlarged partial cross-sectional view of the substrate in Modification 1 of the present disclosure after Steps D, B, and C are performed a predetermined number of times in this order after the execution of Step C. FIG. 8(a) is an enlarged partial cross-sectional view of the substrate in Modification 2 of the present disclosure after supplying a gas containing a hydrogen element in Step D in the first cycle when Steps D, B, and C are performed a predetermined number of times in this order after the execution of Steps A to C. FIG. 8(b) is an enlarged partial cross-sectional view of the substrate in Modification 2 of the present disclosure after supplying a gas containing a Group 14 element in Step D in the first cycle when Steps D, B, and C are performed a predetermined number of times in this order after the execution of Steps A to C.

[0008] <One Aspect of the Present Disclosure> Hereinafter, description will be made while referring to FIGS. 1 to 4, FIGS. 5(a) to 5(h), and the like. Note that the drawings used in the following description are all schematic, and the dimensional relationships and ratios of the respective elements shown in the drawings do not necessarily match the actual ones. Also, the dimensional relationships and ratios of the respective elements do not necessarily match among the plurality of drawings.

[0009] (1) As shown in the configuration diagram of the substrate processing apparatus in FIG. 1, the processing furnace 202 has a heater 207 as a temperature adjuster (heating unit). The heater 207 has a cylindrical shape and is vertically installed by being supported by a holding plate. The heater 207 also functions as an activation mechanism for activating gas with heat.

[0010] Inside the heater 207, a reaction tube 203 is arranged concentrically with the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz or silicon carbide (SiC), and is formed in a cylindrical shape with the upper end closed and the lower end open. Below the reaction tube 203, a manifold 209 (hereinafter MF209) is arranged concentrically with the reaction tube 203. MF209 is made of a metal material such as stainless steel, and is formed in a cylindrical shape with the upper and lower ends open. The upper end of MF209 is engaged with the lower end of the reaction tube 203 and is configured to support the reaction tube 203. An O-ring 220a as a seal member is provided between MF209 and the reaction tube 203. The reaction tube 203 is vertically installed in the same manner as the heater 207. Mainly, the reaction tube 203 and MF209 constitute a processing container (reaction container). A processing chamber 201 is formed in the cylindrical hollow portion of the processing container. The processing chamber 201 is configured to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed in this processing chamber 201.

[0011] In the processing chamber 201, nozzles 249a to 249e as the first to fifth supply units are respectively provided so as to penetrate the side wall of MF209. Gas supply pipes 232a to 232e are respectively connected to the nozzles 249a to 249e. The nozzles 249a to 249e are different nozzles, and each of the nozzles 249b and 249d is provided adjacent to the nozzle 249c. Each of the nozzles 249a and 249e is provided adjacent to the side opposite to the side adjacent to the nozzle 249c of the nozzles 249b and 249d.

[0012] Gas supply pipes 232a to 232e are equipped with, in order from the upstream side of the gas flow, mass flow controllers (MFCs) 241a to 241e and valves 243a to 243e, which are flow control devices (flow control units). Downstream of valves 243a to 243e in gas supply pipes 232a to 232e, gas supply pipes 232f to 232j are connected, respectively. Gas supply pipes 232f to 232j are equipped with, in order from the upstream side of the gas flow, MFCs 241f to 241j and valves 243f to 243j, respectively. Gas supply pipes 232a to 232e are made of a metal material such as SUS.

[0013] Nozzles 249a to 249e are provided in an annular space in plan view between the inner wall of the reaction tube 203 and the wafer 200, extending from the lower to the upper part of the inner wall of the reaction tube 203, rising upward in the direction of wafer 200 arrangement. That is, nozzles 249a to 249e are provided in a region horizontally surrounding the wafer arrangement region, on the side of the wafer arrangement region where the wafers 200 are arranged, and are provided along the wafer arrangement region. In plan view, nozzle 249c is positioned to face the exhaust port 231a, described later, in a straight line with respect to the center of the wafer 200 being transported into the processing chamber 201. Nozzles 249b and 249d are positioned to sandwich a straight line L passing through the center of nozzle 249c and the exhaust port 231a from both sides along the inner wall of the reaction tube 203 (outer periphery of the wafer 200). Furthermore, nozzles 249a and 249e are positioned so as to sandwich a straight line L from both sides along the inner wall of the reaction tube 203, on the opposite side from the side adjacent to nozzle 249c of nozzles 249b and 249d. The straight line L is also the straight line passing through nozzle 249c and the center of the wafer 200. In other words, nozzle 249d can be said to be located on the opposite side of nozzle 249b with respect to the straight line L. Similarly, nozzle 249e can be said to be located on the opposite side of nozzle 249a with respect to the straight line L. Nozzles 249b and 249d are arranged symmetrically with respect to the straight line L as the axis of symmetry. Also, nozzles 249a and 249e are arranged symmetrically with respect to the straight line L as the axis of symmetry. Gas supply holes 250a to 250e for supplying gas are provided on the sides of nozzles 249a to 249e, respectively. Each of the gas supply holes 250a to 250e is opened so as to face the exhaust port 231a in a plan view, and it is possible to supply gas toward the wafer 200. Multiple gas supply holes 250a to 250e are provided extending from the bottom to the top of the reaction tube 203.

[0014] From the gas supply pipe 232a, a first gas containing a group 14 element, or a gas containing a group 14 element (hereinafter also referred to as the group 14 element-containing gas), is supplied into the processing chamber 201 via the MFC 241a, valve 243a, and nozzle 249a. The first gas is also referred to as the first group 14 element-containing gas.

[0015] From the gas supply pipe 232b, a second gas containing Group 14 elements is supplied into the processing chamber 201 via the MFC 241b, valve 243b, and nozzle 249b. The second gas is also referred to as the second Group 14 element-containing gas.

[0016] From the gas supply pipe 232c, a third gas containing a second halogen element, or a gas containing a third halogen element (hereinafter also referred to as third halogen element-containing gas), is supplied into the processing chamber 201 via the MFC 241c, valve 243c, and nozzle 249c.

[0017] From the gas supply pipe 232d, a gas containing hydrogen halogen (hereinafter also referred to as hydrogen halogen-containing gas) is supplied into the processing chamber 201 via the MFC 241d, valve 243d, and nozzle 249d.

[0018] From the gas supply pipe 232e, a gas containing hydrogen (H) element (hereinafter also referred to as H-containing gas) is supplied into the processing chamber 201 via the MFC 241e, valve 243e, and nozzle 249e.

[0019] Inert gas is supplied from gas supply pipes 232f to 232j into the processing chamber 201 via MFCs 241f to 241j, valves 243f to 243j, gas supply pipes 232a to 232e, and nozzles 249a to 249e, respectively. The inert gas acts as a purge gas, carrier gas, diluent gas, etc.

[0020] The first gas supply system or a gas supply system containing group 14 elements is mainly composed of gas supply pipes 232a, MFC 241a, and valve 243a. The second gas supply system is mainly composed of gas supply pipes 232b, MFC 241b, and valve 243b. The third gas supply system or a gas supply system containing a third halogen element is mainly composed of gas supply pipes 232c, MFC 241c, and valve 243c. The hydrogen halide-containing gas supply system is mainly composed of gas supply pipes 232d, MFC 241d, and valve 243d. The H-containing gas supply system is mainly composed of gas supply pipes 232e, MFC 241e, and valve 243e. The inert gas supply system is mainly composed of gas supply pipes 232f to 232j, MFC 241f to 241j, and valves 243f to 243j. Furthermore, nozzles connected to the gas supply pipes that constitute the various supply systems described above may be included in each of those supply systems.

[0021] As shown in Figure 1, an exhaust port 231a for exhausting the atmosphere inside the processing chamber 201 is provided at the lower part of the side wall of the reaction tube 203. As shown in Figure 2, in a plan view, the exhaust port 231a is located opposite (facing) the nozzles 249a to 249e (gas supply holes 250a to 250e) with the wafer 200 in between. The exhaust port 231a may be provided along the upper part of the side wall of the reaction tube 203, that is, along the wafer arrangement region. An exhaust pipe 231 is connected to the exhaust port 231a. As shown in Figure 1, a vacuum pump 246, which is a vacuum exhaust device, is connected to the exhaust pipe 231 via a pressure sensor 245, which is a pressure detector (pressure detection unit) for detecting the pressure inside the processing chamber 201, and an APC (Auto Pressure Controller) valve 244, which is a pressure regulator (pressure adjustment unit). The APC valve 244 can be opened and closed while the vacuum pump 246 is operating to evacuate and stop the vacuum evacuation from the processing chamber 201. Furthermore, while the vacuum pump 246 is operating, the valve opening can be adjusted based on the pressure information detected by the pressure sensor 245 to adjust the pressure inside the processing chamber 201. The exhaust system mainly consists of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may also be considered as part of the exhaust system.

[0022] Below the MF209, a seal cap 219 (hereinafter SC219) is provided as a furnace opening cover capable of airtightly closing the lower end opening of the MF209. The SC219 is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220b is provided on the upper surface of the SC219 as a sealing member that contacts the lower end of the MF209. Below the SC219, a rotating mechanism 267 for rotating the boat 217, which will be described later, is installed. The rotating shaft 255 of the rotating mechanism 267 passes through the SC219 and is connected to the boat 217. The rotating mechanism 267 is configured to rotate the wafer 200 by rotating the boat 217. The SC219 is configured to be raised and lowered vertically by a boat elevator 115 (hereinafter BE115), which is a lifting mechanism installed outside the reaction tube 203. BE115 is configured as a transport device (transport mechanism) that moves the wafer 200 in and out of the processing chamber 201 by raising and lowering SC219. Below MF209, a shutter 219s is provided as a furnace opening cover that can airtightly close the lower end opening of MF209 when SC219 is lowered and the boat 217 has been removed from inside the processing chamber 201. The shutter 219s is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220c is provided on the upper surface of the shutter 219s as a sealing member that contacts the lower end of MF209. The opening and closing operation of the shutter 219s (such as raising and lowering operation and rotation operation) is controlled by the shutter opening and closing mechanism 115s.

[0023] The boat 217, which serves as a substrate support, is configured to support multiple wafers 200, for example 25 to 200 wafers 200, in a horizontal position and aligned vertically with their centers aligned, in a multi-stage arrangement, that is, arranged with spacing between them. The boat 217 is made of a heat-resistant material such as quartz or SiC. At the bottom of the boat 217, a multi-stage insulation plate 218, also made of a heat-resistant material such as quartz or SiC, is supported.

[0024] A temperature sensor 263 is installed inside the reaction tube 203 as a temperature detector. By adjusting the amount of power supplied to the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature inside the processing chamber 201 is adjusted to the desired temperature distribution. The temperature sensor 263 is installed along the inner wall of the reaction tube 203.

[0025] As shown in Figure 3, the controller 121, which is the control unit (control means), is configured as a computer equipped with a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, storage device 121c, and I / O port 121d. The RAM 121b, storage device 121c, and I / O port 121d are configured to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122, configured as, for example, a touch panel, is connected to the controller 121.

[0026] The storage device 121c is composed of, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. The storage device 121c contains, in a readable format, control programs that control the operation of the substrate processing apparatus, and process recipes that describe the procedures and conditions for substrate processing, as described later. The process recipe is a combination of steps in the substrate processing described later that cause the controller 121 to execute and obtain predetermined results, and functions as a program. Hereinafter, process recipes and control programs will be collectively referred to simply as "programs." Similarly, process recipes will be simply referred to as "recipes." In this disclosure, the term "program" may include only recipes, only control programs, or both. The RAM 121b is configured as a memory area where programs and data read by the CPU 121a are temporarily held.

[0027] The I / O port 121d is connected to the MFCs 241a to 241j, valves 243a to 243j, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotating mechanism 267, BE 115, shutter opening / closing mechanism 115s, etc.

[0028] The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read a recipe from the storage device 121c in response to input of operation commands from the input / output device 122. The CPU 121a is configured to control the flow rate adjustment operation of various gases by the MFCs 241a to 241j, the opening and closing operation of valves 243a to 243j, the opening and closing operation of the APC valve 244 and the pressure adjustment operation of the APC valve 244 based on the pressure sensor 245, the starting and stopping of the vacuum pump 246, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the rotation and rotation speed adjustment operation of the boat 217 by the rotating mechanism 267, the raising and lowering operation of the boat 217 by the BE 115, and the opening and closing operation of the shutter 219s by the shutter opening and closing mechanism 115s, in accordance with the contents of the read recipe.

[0029] The controller 121 can be configured by installing the above-mentioned program, which is recorded and stored in the external storage device 123, onto a computer. The external storage device 123 includes, for example, magnetic disks such as HDDs, optical disks such as CDs, USB memory, and semiconductor memory such as SSDs. The storage device 121c and the external storage device 123 are configured as computer-readable recording media. Hereinafter, these will be collectively referred to simply as recording media. In this disclosure, the term recording media may include only the storage device 121c, only the external storage device 123, or both. The program (program product) may be provided to the computer using communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0030] (2) Substrate Processing Process Using the substrate processing apparatus described above, a method for processing a substrate (processing method), that is, an example of a processing sequence for forming a film on a wafer 200 as a substrate, will be explained mainly with reference to Figures 4 and 5(a) to 5(h). In the following explanation, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

[0031] In this embodiment, an example is described in which a wafer 200 having recesses such as trenches, grooves, and holes, which are three-dimensional structures, are formed on its surface.

[0032] In this specification, the term "recess" is not limited to shapes having a bottom surface, but may also include structures such as gaps or through-holes that do not have a bottom surface. In the case of structures that do not have a bottom surface, "bottom side" may mean the direction (side) from each of the two or more openings toward the back of the structure.

[0033] In this embodiment, the processing sequence includes: (a) step A, which involves supplying a first gas containing a group 14 element to form a first film 200c containing the group 14 element preferentially on the group 14 element exposed surface at the bottom of the recess of the wafer 200; (b) step B, which involves supplying a second gas containing a group 14 element to form a second film 200d containing a group 14 element in the recess of the wafer 200; (c) step C, which involves supplying a third gas containing a second halogen element to etch a portion of the second film 200d; and (d) step D, which involves removing the second halogen element remaining on the wafer 200 after (c).

[0034] The following example describes a case where steps A, B, and C are performed in that order, followed by steps D, B, and C being performed in that order, and this cycle is repeated a predetermined number of times (n times, where n is an integer of 1 or more).

[0035] In the following example, we will describe a case in which, before step A, (e) step E is performed to supply a gas containing a third halogen element to remove the native oxide film 200f etc. formed on the surface of the wafer 200, and further, (f) step F is performed to remove the halogen element remaining on the wafer 200.

[0036] In this specification, the term "wafer" may refer to the wafer itself or to a laminate of a wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of the wafer" may refer to the surface of the wafer itself or to the surface of a predetermined layer formed on the wafer. In this specification, when it is stated that "a predetermined layer is formed on the wafer," it may mean that the predetermined layer is formed directly on the surface of the wafer itself or that the predetermined layer is formed on a layer already formed on the wafer. In this specification, the term "substrate" has the same meaning as when it is used with the term "wafer."

[0037] In this specification, when describing, for example, the adsorption or reaction of the first to third gases to the surface of the wafer 200, it may include not only embodiments in which they adsorb or react to the wafer surface while remaining undecomposed, but also embodiments in which they decompose or intermediates generated by the detachment of their ligands adsorb or react to the wafer 200 surface.

[0038] (Wafer loading and boat loading) Once multiple wafers 200 are loaded into the boat 217, the shutter 219s is moved by the shutter opening / closing mechanism 115s, opening the lower end opening of the MF 209. Then, as shown in Figure 1, the boat 217 supporting the multiple wafers 200 is lifted by the BE 115 and loaded into the processing chamber 201. In this state, the SC 219 seals the lower end of the MF 209 via the O-ring 220b.

[0039] A recess is formed on the surface of the wafer 200 loaded into the boat 217. Here, as an example, we will describe a case where the bottom 200a of the recess is made of a material mainly composed of Group 14 elements, and the side wall 200b inside the recess is made of an insulating material (insulating film) mainly composed of Group 14 elements (see Figure 5(a)). As another example, we will describe a case where a native oxide film 220f is formed on the surface of the bottom 200a of the recess.

[0040] (Pressure and Temperature Adjustment) The processing chamber 201, i.e., the space where the wafer 200 is located, is evacuated (reduced pressure exhaust) by a vacuum pump 246 so that it reaches the desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by a pressure sensor 245, and the APC valve 244 is controlled based on this measured pressure information. The wafer 200 inside the processing chamber 201 is also heated by a heater 207 so that it reaches the desired film deposition temperature. At this time, the amount of power supplied to the heater 207 is controlled based on the temperature information detected by the temperature sensor 263 so that the processing chamber 201 has the desired temperature distribution. The rotation of the wafer 200 by the rotation mechanism 267 is also started. The exhaust of the processing chamber 201, the heating of the wafer 200, and the rotation are all carried out continuously at least until the processing of the wafer 200 is completed.

[0041] (Step E: Removal of native oxide film, etc.) In step E, a gas containing a third halogen element is supplied to the wafer 200 in the processing chamber 201, that is, to the wafer 200 on which depressions have been formed on the surface.

[0042] Specifically, valve 243c is opened, and a gas containing a third halogen element flows into the gas supply pipe 232c. The flow rate of the gas containing the third halogen element is adjusted by MFC 241c, supplied to the processing chamber 201 via nozzle 249c, and exhausted from exhaust port 231a. At this time, the gas containing the third halogen element is supplied to the wafer 200 (supply of gas containing the third halogen element). At this time, valves 243f to 243j may be opened, and inert gas may be supplied to the processing chamber 201 via nozzles 249a to 249e, respectively.

[0043] By supplying a gas containing a third halogen element to the wafer 200 under the processing conditions described later, for example, the native oxide film 220f formed on the surface of the bottom 200a of the recess can be removed (etched), exposing the surface of the bottom 200a (see Figures 6(a) and 6(b)).

[0044] In this case, the gas containing the third halogen element may be preferentially adsorbed on the opening side of the recess, and an adsorption inhibitor 200g may be formed whose surface is terminated by atoms of the third halogen element (third halogen termination) (see Figure 6(b)). This adsorption inhibitor 200g suppresses the adsorption of the first gas supplied in step A, described later, onto the opening side, and promotes film formation from the bottom 200a side of the recess in step A.

[0045] Examples of processing conditions when supplying the gas containing the third halogen element in this step include: processing temperature: 300 to 700°C, preferably 350 to 650°C; processing pressure: 1 to 200 Pa, preferably 10 to 100 Pa; processing time: 1 to 60 minutes, preferably 1 to 20 minutes; flow rate of the gas containing the third halogen element: 0.001 to 0.4 slm; flow rate of the inert gas (per gas supply pipe): 0 to 5 slm.

[0046] In this specification, numerical ranges such as "300 to 700°C" mean that the lower and upper limits are included within that range. For example, "300 to 700°C" means "330°C or more and 700°C or less." The same applies to other numerical ranges. In this specification, processing temperature means the temperature of the wafer 200 or the temperature inside the processing chamber 201, and processing pressure means the pressure inside the processing chamber 201, in other words, the pressure of the space in which the wafer 200 is located. Processing time means the time during which the processing is continued. When the supply flow rate includes 0 slm, 0 slm means the case in which the substance (gas) is not supplied. These also apply in the following explanations.

[0047] As the third halogen element-containing gas, a gas can be used that contains at least one of the following as the third halogen element: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), etc.

[0048] As the third halogen element-containing gas, a Cl-containing gas containing, for example, Cl as the third halogen element can be used. ２ ) gas, hydrogen chloride (HCl) gas, hydrogen (H ２ ) + Cl２ The following can be used.

[0049] As the third halogen element-containing gas, a gas containing, for example, fluorine (F) as the third halogen element can be used. As the F-containing gas, for example, hydrogen fluoride (HF) gas can be used.

[0050] As the third halogen element-containing gas, an I-containing gas containing, for example, I as the third halogen element can be used. As the I-containing gas, for example, hydrogen iodide (HI) gas can be used.

[0051] One or more of these can be used as the gas containing the third halogen element.

[0052] Examples of inert gases include nitrogen (N ２ Other gases such as argon (Ar), helium (He), neon (Ne), and xenon (Xe) can be used. One or more of these can be used as the inert gas. This also applies to each of the steps described later.

[0053] After removing the native oxide film 220f formed on the surface of the bottom 200a of the recess, valve 243c is closed to stop the supply of the gas containing the third halogen element into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any gaseous substances remaining in the processing chamber 201. At this time, valves 243f to 243j are opened to supply inert gas into the processing chamber 201 via nozzles 249a to 249e. The inert gas supplied from nozzles 249a to 249e acts as a purge gas, thereby purging the processing chamber 201.

[0054] (Halogen element removal process: Step F) In Step F, H-containing gas is supplied to the wafer 200 in the processing chamber 201, that is, the wafer 200 from which the native oxide film 220f has been removed.

[0055] Specifically, open valve 243e and flow the H-containing gas into gas supply pipe 232e. The H-containing gas is adjusted in flow rate by MFC 241e, supplied into processing chamber 201 via nozzle 249e, and exhausted from exhaust port 231a. At this time, the H-containing gas is supplied to wafer 200 (H-containing gas supply). At this time, valves 243f to 243j may be opened to supply an inert gas into processing chamber 201 via each of nozzles 249a to 249e.

[0056] By supplying the H-containing gas to wafer 200 under the processing conditions described later, for example, the adsorption inhibitor 200g remaining on the sidewall 200b of the concave portion can be removed (see Fig. 6(c)).

[0057] As the processing conditions when supplying the H-containing gas in this step, the processing temperature is 300 to 700 °C, preferably 400 to 700 °C, the processing pressure is 1 to 1000 Pa, the processing time is 1 to 60 minutes, preferably 1 to 20 minutes, the H-containing gas supply flow rate is 0.05 to 1 slm, preferably 0.1 to 0.5 slm, and the inert gas supply flow rate (per gas supply pipe) is 0 to 5 slm.

[0058] Examples of the H-containing gas include H ２ gas, deuterium (D ２ ) gas and other simple H gases, oxides containing H such as water vapor (H ２ O), mixed gases containing H such as H ２ gas + O ２ gas, monosilane (SiH ４ , abbreviation: MS) gas, disilane (Si ２ H ６ , abbreviation: DS) gas, monoborane (BH ３ ) gas, diborane (B ２ H ６ ) gas, phosphine (PH ３ ) gas and other hydrides can be used. As the H-containing gas, one or more of these can be used. This also applies to step D described later. In this specification, the combined description of two gases such as "H ２ gas + O ２ gas" means H ２ gas and O２ This refers to a mixed gas. When supplying a mixed gas, the two gases may be mixed (premixed) in the supply pipe before being supplied into the processing chamber 201, or the two gases may be supplied separately to the processing chamber 201 from different supply pipes and then mixed (postmixed) within the processing chamber 201.

[0059] After removing 200g of adsorption inhibitors remaining on the surface of the wafer 200, the valve 243e is closed to stop the supply of H-containing gas into the processing chamber 201. Then, gaseous substances and the like remaining in the processing chamber 201 are removed from the processing chamber 201 using a processing procedure similar to the purging in step E.

[0060] (First film formation process: Step A) In Step A, a first gas containing a Group 14 element is supplied to the wafer 200 in the processing chamber 201.

[0061] Specifically, valve 243a is opened and the first gas flows into the gas supply pipe 232a. The flow rate of the first gas is adjusted by MFC 241a and supplied into the processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, the first gas is supplied to the wafer 200 (first gas supply). At this time, valves 243f to 243j may be opened and inert gas may be supplied into the processing chamber 201 via nozzles 249a to 249e, respectively.

[0062] Under the processing conditions described later, by supplying a first gas containing a group 14 element to the wafer 200, a first film 200c mainly composed of group 14 elements can be preferentially formed on the group 14 element exposed surface at the bottom 200a of the recess (see Figure 5(b)). This is because the rate of film formation differs depending on the reactivity between the material in the recess and the first gas, and also because, when a gas containing a first halogen element (described later) is used as the first gas, the first halogen element generated by the decomposition of the first gas preferentially adsorbs from the opening side of the recess to the side wall 200b, inhibiting the formation of the first film 200c. As a result, the first film 200c can be preferentially (selectively) formed from the bottom 200a side of the recess.

[0063] Examples of processing conditions when supplying the first gas in this step include: Processing temperature: 300 to 700°C, preferably 400 to 700°C Processing pressure: 1 to 1000 Pa Processing time: 10 to 60 minutes, preferably 30 to 60 minutes First gas supply flow rate: 0.1 to 3 slm First gas supply time: 10 to 60 minutes, preferably 30 to 60 minutes Inert gas supply flow rate (per gas supply pipe): 0 to 5 slm. The processing conditions shown here are conditions under which the first gas will thermally decompose when it is present alone in the processing chamber 201, that is, conditions under which a CVD (Chemical Vapor Deposition) reaction will occur.

[0064] As the first gas containing a Group 14 element, a silane-based gas containing, for example, silicon (Si) as the Group 14 element can be used. As the silane-based gas, for example, a gas containing Si and a first halogen element, i.e., a halosilane-based gas, can be used. The first halogen element includes Cl, F, Br, I, etc. The first halogen element may be the same element as the third halogen element, or it may be a different element.

[0065] For example, the first gas is hexachlorodisilane (Si ２ Cl ６ ) gas, octachlorotrisilane (Si ３ Cl ８ Chlorosilane-based gases such as ) can be used.

[0066] Furthermore, as the first gas, for example, dichlorosilane (SiH ２ Cl ２ ) gas, monochlorosilane (SiH ３ Cl) gas, tetrachlorosilane (SiCl ４ ) gas, trichlorosilane (SiHCl ３ It is preferable to use a chlorosilane-based gas such as ) gas, which contains hydrogen (also referred to as H) in one molecule. When such a gas is used, hydrogen halide is generated by the decomposition of the first gas, and this hydrogen halide inhibits the formation of the first film 200c on the side wall 200b side of the recess, so that the first film 200c can be preferentially formed from the bottom 200a side of the recess.

[0067] For example, the first gas is tetrafluorosilane (SiF ４ ) gas, difluorosilane (SiH ２ F ２ Fluorosilane gases such as ) and tetrabromosilane (SiBr ４ ) gas, dibromosilane (SiH ２ Br ２ Bromosilane-based gases such as ) and tetraiodosilane (SiO2) ４ ) gas, diiodosilane (SiH ２ I ２ Gases containing iodosilane-based gases such as ) can be used.

[0068] One or more of these can be used as the first gas. This also applies to step D, which will be described later.

[0069] After forming the first film 200c at the bottom 200a of the recess, the valve 243a is closed to stop the supply of the first gas into the processing chamber 201. Then, using a processing procedure similar to the purging in step E, any gaseous substances remaining in the processing chamber 201 are removed from the processing chamber 201.

[0070] (Second film formation process: Step B) In Step B, a second gas containing a Group 14 element is supplied to the wafer 200 in the processing chamber 201, that is, the wafer 200 on which the first film 200c has been formed at the bottom 200a of the recess.

[0071] Specifically, valve 243b is opened, and the second gas flows into the gas supply pipe 232b. The flow rate of the second gas is adjusted by MFC 241b, supplied into the processing chamber 201 via nozzle 249b, and exhausted from exhaust port 231a. At this time, the second gas is supplied to the wafer 200 (second gas supply). At this time, valves 243f to 243j may be opened, and inert gas may be supplied into the processing chamber 201 via nozzles 249a to 249e, respectively.

[0072] Under the processing conditions described later, by supplying a second gas containing a Group 14 element to the wafer 200, a second film 200d containing a Group 14 element as the main element can be formed in the recesses of the wafer 200 (see Figure 5(c)). Since the second film 200d grows (forms) on both the side walls 200b and the bottom 200a of the recesses, it is conformally deposited on the recesses. This is because, for example, if a gas that does not contain halogen elements is used as the second gas, halogen elements that inhibit film formation do not adsorb inside the recesses (for example, near the opening of the recesses or on the side walls 200b).

[0073] Furthermore, when a hydride that does not contain halogen elements is used as the second gas, thermal decomposition tends to proceed more easily compared to the first gas (for example, a silane-based gas containing a first halogen element). Therefore, the deposition rate of the second film 200d can be made higher than that of the first film 200c. Moreover, as described above, if a gas containing a first halogen element is used as the first gas in step A, the first halogen element may be adsorbed from the opening side of the recess to the side wall 200b. In contrast, by using a hydride that does not contain halogen elements as the second gas in step B, the second film 200d can be formed while removing the first halogen element that acts as an adsorption inhibitor. As a result, it becomes possible to form the second film 200d conformally.

[0074] Examples of processing conditions when supplying the second gas in this step include: Processing temperature: 300 to 700°C, preferably 400 to 700°C; Processing pressure: 1 to 1000 Pa; Processing time: 10 to 60 minutes, preferably 30 to 60 minutes; Second gas supply flow rate: 0.1 to 3 slm; Inert gas supply flow rate (per gas supply pipe): 0 to 5 slm. The processing conditions shown here are those under which the second gas will undergo thermal decomposition when present alone in the processing chamber 201, i.e., conditions under which a CVD reaction will occur.

[0075] As the second gas containing a Group 14 element, if the Group 14 element is Si, a silane-based gas can be used. For example, monosilane (SiH) is a second gas. ４ (Abbreviation: MS) gas, disilane (Si２ H ６ (Abbreviation: DS) gas, trisilane (Si ３ H ８ ) gas, tetrasilane (Si ４ H １０ ) gas, pentasilan (Si ５ H １２ ) gas, hexasilane (Si ６ H １４ A silicon hydride gas that does not contain halogen elements, such as ) gas, can be used.

[0076] When the Group 14 element is germanium (Ge), a Ge-containing gas can be used as the second gas. The second gas can be Germanium (GeH). ４ ) Gas, Zigelmann (Ge ２ H ６ ) Gas, Trigelmann (Ge ３ H ８ ) gas, tetragerman (Ge ４ H １０ ) gas, pentagelmann (Ge ５ H １２ ) gas, hexagermane (Ge ６ H １４ Germanium hydride gas that does not contain halogen elements such as ) can be used.

[0077] As the second gas, it is preferable to use MS gas, DS gas, trisilane gas, German gas, digermann gas, or trigermann gas. Since these gases react (decompose) relatively easily, the deposition rate of the second film 200d can be improved. Alternatively, a combination of a gas containing Si and a gas containing Ge may be used as the second gas. In this case, a second film 200d containing Si and Ge can be formed.

[0078] One or more of these can be used as the second gas.

[0079] After forming the second film 200d in the recess of the wafer 200, the valve 243b is closed to stop the supply of the second gas into the processing chamber 201. Then, using a processing procedure similar to the purging in step E, any gaseous substances remaining in the processing chamber 201 are removed from the processing chamber 201.

[0080] (Partial removal of the second film: Step C)

[0081] In step C, a third gas containing a second halogen element is supplied to the wafer 200 in the processing chamber 201, that is, the wafer 200 in which the second film 200d is formed in the recess.

[0082] Specifically, valve 243c is opened, and the third gas flows into the gas supply pipe 232c. The flow rate of the third gas is adjusted by MFC 241c, supplied into the processing chamber 201 via nozzle 249c, and exhausted from exhaust port 231a. At this time, the third gas is supplied to the wafer 200 (third gas supply). At this time, valves 243f to 243j may be opened, and inert gas may be supplied into the processing chamber 201 via nozzles 249a to 249e, respectively.

[0083] Under the processing conditions described later, a third gas containing a second halogen element can be supplied to the wafer 200 to etch (remove) a portion of the second film 200d (for example, the portion formed on the opening side of the recess) (see Figure 5(d)). As described above, in step B, the deposition rate of the second film 200d is relatively high, so voids and seams may be formed inside it. Therefore, by etching a portion of the second film 200d in step C, a second film 200d from which voids and seams have been removed can be obtained. At this time, the third gas may be adsorbed on the side wall 200b of the recess, and a by-product 200e with its surface terminated by atoms of the second halogen element (second halogen termination) may remain (see Figure 5(d)). The by-product 200e (specifically, the second halogen termination) can act as an inhibitor to suppress the adsorption of the first gas and second gas supplied in steps D and B described later.

[0084] Examples of processing conditions when supplying the third gas in this step include: processing temperature: 300 to 700°C, preferably 400 to 700°C; processing pressure: 1 to 1000 Pa; processing time: 10 to 60 minutes, preferably 30 to 60 minutes; third gas supply flow rate: 0.1 to 3 slm; inert gas supply flow rate (per gas supply pipe): 0 to 5 slm.

[0085] As the third gas containing the second halogen element, a gas containing at least one of the following can be used as the second halogen element: for example, F, Cl, Br, I, etc. The second halogen element may be the same element as the first or third halogen element, or it may be a different element.

[0086] As the third gas, a gas containing one or more of the gases listed as third halogen element-containing gases can be used.

[0087] After etching a portion of the second film 200d, the valve 243c is closed to stop the supply of the third gas into the processing chamber 201. Then, using a processing procedure similar to the purging in step E, any remaining gaseous substances in the processing chamber 201 are removed from the processing chamber 201.

[0088] (By-product removal (deactivation) process: Step D) In ​​Step D, the first gas, a hydrogen halide-containing gas, and an H-containing gas are supplied to the wafer 200 in the processing chamber 201, i.e., the wafer 200 from which a portion of the second film 200d has been etched.

[0089] Specifically, valves 243a, 243c, and 243e are opened, and the first gas, hydrogen halogen-containing gas, and H-containing gas are flowed into the gas supply pipes 232a, 232c, and 232e, respectively. The flow rates of the first gas, hydrogen halogen-containing gas, and H-containing gas are adjusted by MFCs 241a, 241c, and 241e, respectively, and supplied into the processing chamber 201 via nozzles 249a, 249c, and 249e, and exhausted from exhaust port 231a. At this time, the first gas, hydrogen halogen-containing gas, and H-containing gas are supplied to the wafer 200 (supply of first gas, hydrogen halogen-containing gas, and H-containing gas). At this time, valves 243f to 243j may be opened, and inert gas may be supplied into the processing chamber 201 via nozzles 249a to 249e, respectively.

[0090] Under the processing conditions described later, by supplying the wafer 200 with a first gas, a hydrogen halide-containing gas, and an H-containing gas, the by-products 200e remaining on the side walls 200b of the recesses can be removed (see Figure 5(e)).

[0091] Specifically, by supplying a first gas to the wafer 200, the first halogen element contained in the first gas can remove byproducts 200e while micro-etching a portion of the second film 200d formed on the sidewall 200b of the recess or the sidewall 200b of the recess. Furthermore, the H contained in the first gas can also remove byproducts 200e. Additionally, the reaction products generated by the reaction between the first halogen element and H in the first gas can remove byproducts 200e while micro-etching a portion of the second film 200d formed on the sidewall 200b of the recess or the sidewall 200b of the recess. Moreover, the group 14 element contained in the first gas can form (deposit) a first film 200c containing the group 14 element on the second film 200d. Thus, by supplying the first gas, the first film 200c can be formed on the second film 200d while removing the byproducts 200e remaining on the sidewall 200b of the recess (see Figure 5(e)).

[0092] By supplying a hydrogen halide-containing gas to the wafer 200, the by-product 200e can be removed while etching away a small portion of the second film 200d formed on the side wall 200b of the recess, or a small portion of the side wall 200b of the recess (see Figure 5(e)).

[0093] By supplying an H-containing gas to the wafer 200, the by-product 200e can be removed (see Figure 5(e)). Specifically, the H-containing gas reacts with the second halogen termination formed on the surface of the by-product 200e, causing the by-product 200e to detach from the wafer 200.

[0094] Furthermore, by simultaneously supplying the first gas, the hydrogen halide-containing gas, and the H-containing gas, the reaction products generated by the interaction of the first gas, the hydrogen halide-containing gas, and the H-containing gas can also remove the by-products 200e remaining on the sidewall 200b of the recess, while slightly etching a portion of the second film 200d formed on the sidewall 200b of the recess or the sidewall 200b of the recess. In this specification, "simultaneous" includes not only the exact same timing but also approximately the same timing and approximate timing.

[0095] Examples of processing conditions when supplying the first gas, hydrogen halide-containing gas, and H-containing gas in this step include: Processing temperature: 300 to 700°C, preferably 400 to 700°C; Processing pressure: 1 to 1000 Pa; Processing time: 10 to 60 minutes, preferably 30 to 60 minutes; First gas supply flow rate: 0.1 to 3 slm; Hydrogen halide-containing gas supply flow rate: 0.1 to 3 slm; H-containing gas supply flow rate: 0.1 to 3 slm; Inert gas supply flow rate (per gas supply pipe): 0 to 5 slm.

[0096] Examples of hydrogen halide-containing gases that can be used include HCl gas, HF gas, hydrogen bromide (HBr) gas, HI gas, etc. One or more of these can be used as the hydrogen halide-containing gas. Alternatively, one or more of these activated gases can be used.

[0097] After removing the by-products 200e remaining on the wafer 200, valves 243a, 243c, and 243e are closed to stop the supply of the first gas, hydrogen halide-containing gas, and H-containing gas into the processing chamber 201. Then, gaseous substances remaining in the processing chamber 201 are removed from the processing chamber 201 using a processing procedure similar to the purging in step E.

[0098] (Step B) Step B is then performed. The second gas is supplied to the wafer 200 using the same processing procedure and conditions as in Step B described above. This allows the second film 200d to be formed in the recesses (see Figure 5(f)). Here, as described above, in Step D, the by-product 200e that suppresses the adsorption of the second gas is removed. Therefore, in Step B, the decrease in the film formation rate of the second film 200d can be suppressed, and furthermore, the second film 200d can be formed conformally in the recesses.

[0099] Subsequently, any gaseous substances remaining in the treatment chamber 201 are removed from the treatment chamber 201 using a treatment procedure similar to the purging procedure in step E.

[0100] (Step C) Step C is then performed. The third gas is supplied to the wafer 200 using the same processing procedure and conditions as described in Step C. This etches a portion of the second film 200d, and a second film 200d with voids and seams removed can be obtained (see Figure 5(g)).

[0101] Subsequently, any gaseous substances remaining in the treatment chamber 201 are removed from the treatment chamber 201 using a treatment procedure similar to the purging procedure in step E.

[0102] [Performed a predetermined number of times] After performing steps E, F, A to C in the order described above, the first film 200c and the second film 200d can be embedded in the recess by performing a cycle of steps D, B, and C in the order described above a predetermined number of times (n times, where n is 1 or an integer of 2 or more). It is preferable to repeat this cycle multiple times. In the above cycle, for example, if the amount of by-product 200e formed on the side wall 200b of the recess is small, step D may be omitted, and for example, if the amount of voids or seams formed in the second film 200d is small, step C may be omitted.

[0103] (After-purging and return to atmospheric pressure) After the processing of the wafer 200 is complete, inert gas is supplied as a purge gas into the processing chamber 201 from nozzles 249a to 249e and exhausted from exhaust port 231a. This purges the processing chamber 201, removing any remaining gases and reaction by-products (purging). Subsequently, the atmosphere inside the processing chamber 201 is replaced with inert gas, and the pressure inside the processing chamber 201 is returned to atmospheric pressure. The output to the heater 207 is also adjusted to perform a cooling process to lower the temperature of the wafer 200. The temperature of the wafer 200 is adjusted to a temperature at which it can be removed from the processing chamber 201.

[0104] (Boat removal and wafer retrieval) The SC219 is lowered by the BE115, and the lower end of the MF209 is opened. The processed wafer 200 is then removed from the reaction tube 203 through the lower end of the MF209 while supported by the boat 217. After the boat is removed, the shutter 219s is moved, and the lower end opening of the MF209 is sealed by the shutter 219s via the O-ring 220c. After the processed wafer 200 has been removed from the reaction tube 203, it is taken out of the boat 217.

[0105] (3) Effects of this embodiment According to this embodiment, one or more of the following effects can be obtained.

[0106] (a) By performing step D, the by-product 200e remaining on the wafer 200 (for example, the side wall 200b of the recess) can be removed. This makes it possible to improve the formation rate of the second film 200d in the next step, step B.

[0107] (b) In step D, by using a first gas containing H, the H in the first gas reacts with the by-product 200e, and the by-product 200e can be removed from the side wall 200b of the recess.

[0108] (c) In step D, by using a first gas containing a first halogen element, the by-product 200e can be removed while etching a small portion of the second film 200d formed on the side wall 200b of the recess or the side wall 200b of the recess.

[0109] (d) In step D, by using a first gas containing a first halogen element and H, the reaction product generated by the reaction between the first halogen element and H in the first gas can remove the by-product 200e while etching (removing) a small portion of the second film 200d formed on the side wall 200b of the recess or the side wall 200b of the recess.

[0110] (e) In step D, by supplying a first gas containing a group 14 element, the by-product 200e remaining on the side wall 200b of the recess can be removed, and at the same time, the first film 200c can be formed in the recess of the wafer 200. In this way, the process of removing unwanted by-products 200e and the film formation process can be carried out in parallel, so the film formation throughput can be improved.

[0111] (f) In step D, supplying an H-containing gas can facilitate the removal of the by-product 200e.

[0112] (g) In step D, by supplying a hydrogen halide-containing gas, the by-product 200e can be removed while etching a portion of the second film 200d formed on the side wall 200b of the recess or the side wall 200b of the recess to a small extent.

[0113] (4) Modifications The substrate processing sequence in this embodiment can be modified as shown below. These modifications can be combined in any way. Unless otherwise specified, the processing procedures and processing conditions in each step of each modification can be the same as the processing procedures and processing conditions in each step of the processing sequence described above.

[0114] (Modification 1) In step D, the first gas and the hydrogen halide-containing gas may be omitted, and only the H-containing gas may be supplied by itself.

[0115] In this modified example, at least some of the effects described in the above-described embodiment can be obtained (see Figures 7(a) to 7(h)). However, the above-described embodiment, in which the first gas, hydrogen halide-containing gas, and H-containing gas are supplied, is preferable because the removal of by-product 200e and the formation of the first film 200c can be performed simultaneously, thereby increasing the film formation rate and improving throughput.

[0116] (Modification 2) In step D, a hydrogen-containing gas and a gas containing a Group 14 element as the first gas may be supplied sequentially. Specifically, for example, the H-containing gas may be supplied first, and then the gas containing the Group 14 element may be supplied. In this case, the supply of the Group 14 element gas may be started after the supply of the H-containing gas is completed, or the supply period of the H-containing gas and the supply of the Group 14 element gas may overlap at least partially. As the gas containing the Group 14 element, a gas containing one or more of the gases exemplified as the first gas above can be used.

[0117] In this modified example, the same effects as in the above-described embodiment can be obtained (see Figures 8(a) and 8(b)). Furthermore, in this modified example, after removing the by-product 200e with an H-containing gas, a film containing a group 14 element (shown as the first film 200c in Figure 8(b)) can be formed (deposited). By sequentially supplying the H-containing gas and the first gas, hydrogen halides are generated on the wafer 200 by the reaction of the H-containing gas and the first gas, or by the decomposition of the first gas. These hydrogen halides inhibit the deposition of the film in this disclosure and can also etch the film to a small extent. As a result, even if damage occurs to the surface of the second film 200d in the preceding step C, the surface can be treated in this modified example. For example, even if the flatness of the second film 200d is reduced by step C, the first film 200c containing the group 14 element can be formed flat on the surface of the second film 200d by removing the by-product 200e with an H-containing gas and then supplying a gas containing a group 14 element.

[0118] <Other Aspects of the Disclosure> The aspects of the Disclosure have been described in detail above. However, the Disclosure is not limited to the aspects described above and can be modified in various ways without departing from its essence.

[0119] Although not described in detail in the above embodiments, in step D, two or more gases from the first gas, the hydrogen halogen-containing gas, and the H-containing gas may be supplied in any combination. In addition to the effects caused by the supply of each gas, the by-product 200e can be removed by the reaction products produced by the reaction between the selected gases. These gases may be supplied simultaneously or at different times. Specifically, examples include the supply of the first gas and the hydrogen halogen-containing gas simultaneously or at different times, the supply of the H-containing gas and the hydrogen halogen-containing gas simultaneously or at different times, the supply of the first gas and the H-containing gas simultaneously or at different times, or the supply of the first gas, the hydrogen halogen-containing gas, and the H-containing gas at different times. As an example, the supply of the H-containing gas may be started first, then the supply of the first gas may be started, and after a period in which the supply of the H-containing gas and the supply of the first gas are performed simultaneously, the supply of each gas may be stopped. By supplying the gas in this manner, as described above, it is possible to obtain not only the effect of the first gas but also the effect of the H-containing gas when treating the surface of the second film 200d. Furthermore, in the case of non-simultaneous supply, the next gas may be supplied after the supply of the preceding gas has been completed, or the supply periods may overlap. In this embodiment as well, the same effects as in the embodiment described above can be obtained.

[0120] In the embodiments described above, the case in step D was explained using the example of supplying only H-containing gas, but the disclosure is not limited thereto. For example, the first gas may be supplied alone, or a hydrogen halide-containing gas may be supplied alone. In this embodiment as well, at least some of the effects described in the embodiments above can be obtained.

[0121] In the embodiments described above, the case in which steps E and F are performed before step A (also referred to as pattern A; see Figures 6(a) to 6(c)) was used as an example, but the disclosure is not limited thereto. For example, step E may be performed before step A, and step F may not be performed (also referred to as pattern B; see Figures 6(a) and 6(b)). Also, for example, if the native oxide film 220f has been removed in advance before the wafer 200 is brought into the processing chamber 201, but the adsorption inhibitor 200g remains, step F may be performed before step A (also referred to as pattern C; see Figures 6(b) and 6(c)). Furthermore, for example, if the native oxide film 220f and adsorption inhibitors 200g have been removed in advance before the wafer 200 is brought into the processing chamber 201, step E may be performed before step A to adsorb a gas containing a third halogen element from the opening side of the recess to the side wall 200b, thereby forming an adsorption inhibitor 200h whose surface is terminated by atoms of the third halogen element (third halogen termination) (also referred to as pattern D; see Figures 6(c) and 6(d)). In this embodiment, the same effects as in the above-described embodiment can be obtained. Moreover, in this embodiment, by forming adsorption inhibitors 200g and 200h in patterns B and D, respectively, the deposition (formation) of the first film 200c on the opening side of the recess can be inhibited in step A, and film deposition from the bottom 200a side of the recess can be further promoted.

[0122] In the embodiments described above, the case in step A where the first gas is supplied alone was used as an example, but the present disclosure is not limited thereto. For example, in step A, in addition to the first gas, at least one of a gas containing a third halogen element and a gas containing a hydrogen halide may be supplied. These gases may be supplied simultaneously or not simultaneously. An example of the supply flow rate for the gas containing the third halogen element and the gas containing a hydrogen halide is 1 to 0.4 slm. Furthermore, in this embodiment, the gas containing the third halogen element and the gas containing a hydrogen halide can be gases containing one or more of the gases exemplified above as the gas containing the third halogen element and the gas containing a hydrogen halide, respectively. The same effects as in the embodiments described above can be obtained in this embodiment as well. Moreover, in this embodiment, by supplying a gas containing the third halogen element in addition to the first gas, the formation of the first film 200c on the side wall 200b of the recess can be inhibited not only by the first halogen element produced by the decomposition of the first gas, but also by the third halogen element contained in the gas containing the third halogen element. This increases the effect of preferentially forming the first film 200c from the bottom 200a side of the recess compared to when the first gas is used alone. Furthermore, in this embodiment, by supplying a hydrogen halide-containing gas in addition to the first gas, the formation of the first film 200c on the side wall 200b of the recess can be suppressed not only by the first halogen element produced by the decomposition of the first gas, but also by the halogen element contained in the hydrogen halide-containing gas, and further by the reaction products generated by the reaction between the first gas and the hydrogen halide-containing gas. In this way, the inhibitory effect on the formation of the first film 200c on the side wall 200b can be further strengthened, and the effect of preferentially forming the film from the bottom 200a side of the recess can be further enhanced.

[0123] Although not described in the above embodiments, in step A and / or step B, a dopant gas may be supplied in addition to the first gas and the second gas. By supplying a dopant gas, the first membrane 200c and / or the second membrane 200d can be doped (added) with a group 13 or group 15 element, as described later. As the dopant gas, a gas containing a group 13 or group 15 element can be used. Examples of group 13 elements include boron (B), aluminum (Al), gallium (Ga), and indium (In). Examples of group 15 elements include phosphorus (P) and arsenic (As). Examples of gases containing group 13 elements include monoborane (BH). ３ ) Gas, diborane (B ２ H ６ ) gas, triborane (B ３ H ８ Borane-based gases such as ) gas (also called boron hydride-based gases) and trichloroborane (BCl) ３ ) Boron halide gases such as gas, and aluminum chloride (AlCl ３ ) gas, gallium chloride (GaCl ３ ) gas, indium chloride (InCl ３ Halide gases such as ) can be used. In addition, gases containing Group 15 elements include, for example, phosphone (PH) ３ ) gas, diphosphine (P ２ H ６ Phosphophanic gases such as ) gas, and phosphorus trichloride (PCL ３ ) Phosphorus halogenated gases such as gases can be used.

[0124] In the embodiments described above, the case in which the Group 14 element contained in the first gas is Si was explained, but this disclosure is not limited to this. For example, the Group 14 element contained in the first gas may be Ge. Also, a combination of a gas containing Si and a gas containing Ge may be used as the first gas. In this case, a first film 200c containing Si and Ge can be formed. In this embodiment as well, at least some of the effects described in the embodiments above can be obtained. Furthermore, the Group 14 element contained in the first gas may be the same as or different from the Group 14 element contained in the second gas. For example, a gas containing Ge may be used as the first gas and a gas containing Si may be used as the second gas, or this may be appropriately selected.

[0125] In the above-described embodiment, a case in which a first film 200c and a second film 200d mainly composed of Group 14 elements are formed in the recess is explained, but the disclosure is not limited thereto. For example, gases that form the first film 200c and the second film 200d mainly composed of any of Group 4, Group 12, or Group 13 elements may be used as the first gas and the second gas.

[0126] It is preferable to prepare (or have multiple) process recipes (programs describing processing procedures and conditions, etc.) used for forming these various thin films, according to the content of the substrate processing (type of film to be formed, composition ratio, film quality, film thickness, processing procedure, processing conditions, etc.). When starting the substrate processing, it is preferable to appropriately select an appropriate process recipe from among the multiple process recipes according to the content of the substrate processing. Specifically, it is preferable to pre-record and store (install) the multiple process recipes prepared individually according to the content of the substrate processing in the storage device 121c of the substrate processing device via an telecommunications line or a recording medium (external storage device 123) on which the process recipes are recorded. When starting the substrate processing, it is preferable for the CPU 121a of the substrate processing device to appropriately select an appropriate process recipe from among the multiple process recipes recorded and stored in the storage device 121c according to the content of the substrate processing. With this configuration, a single substrate processing device can form thin films of various types, composition ratios, film quality, and film thickness in a general-purpose and reproducible manner. Furthermore, it reduces the operator's workload (such as the burden of inputting processing procedures and conditions), allowing for quicker initiation of substrate processing while avoiding operational errors.

[0127] Furthermore, this disclosure can also be implemented, for example, by changing the process recipe of an existing substrate processing apparatus. When changing the process recipe, it is possible to install the process recipe relating to this disclosure into the existing substrate processing apparatus via a telecommunications line or a recording medium on which the process recipe is stored, or to change the process recipe itself to the process recipe relating to this disclosure by operating the input / output device of the existing substrate processing apparatus.

[0128] Furthermore, this disclosure can be used, for example, in the manufacturing process of NAND flash memory, DRAM, LOGIC, etc., which have a three-dimensional structure.

[0129] The above-described embodiments illustrate an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at once. This disclosure is not limited to the above embodiments and can be suitably applied, for example, to forming a film using a single-wafer substrate processing apparatus that processes one or several substrates at once. Furthermore, the above-described embodiments illustrate an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace. This disclosure is not limited to the above embodiments and can be suitably applied to forming a film using a substrate processing apparatus having a cold-wall type processing furnace.

[0130] The above-described embodiments and modifications can be used in combination as appropriate. The processing procedure and processing conditions in this case can be the same as, for example, the processing procedure and processing conditions of the above-described embodiments and modifications.

[0131] 200 Wafer (substrate) 200c First layer 200d Second layer

Claims

1. A substrate processing method comprising: (a) supplying a first gas containing a group 14 element to form a first film containing the group 14 element preferentially on the group 14 element exposed surface at the bottom of a recess in the substrate; (b) supplying a second gas containing a group 14 element to form a second film containing the group 14 element in the recess of the substrate; (c) supplying a third gas containing a second halogen element to etch a portion of the second film; and (d) removing the second halogen element remaining on the substrate after (c).

2. (d) The substrate processing method according to claim 1, wherein the first gas is supplied.

3. The substrate processing method according to claim 2, wherein the first gas contains the element hydrogen.

4. The substrate processing method according to claim 3, wherein the first gas contains a first halogen element.

5. The substrate processing method according to claim 1, wherein the second gas is a gas containing the element hydrogen.

6. The substrate processing method according to claim 5, wherein the second gas is a gas that does not contain halogen elements.

7. (d) The substrate processing method according to claim 3, wherein a gas containing hydrogen halide is supplied.

8. The substrate processing method according to claim 7, wherein the hydrogen halide is at least one of hydrogen chloride, hydrogen iodide, and hydrogen fluoride.

9. The substrate processing method according to claim 4, wherein the side wall of the recess is an insulating film.

10. The substrate processing method according to claim 9, wherein the insulating film is a film containing a Group 14 element.

11. The substrate processing method according to claim 1, wherein (d) the first gas is supplied to form the first film on the second film while removing the second halogen element.

12. The substrate processing method according to claim 11, wherein a predetermined number of cycles are performed in which (a), (b), and (c) are performed in that order, and then (d), (b), and (c) are performed in that order.

13. (d) The substrate processing method according to claim 1, wherein the first gas is supplied to remove a portion of the second film and the second halogen element.

14. (d) The substrate processing method according to claim 1, wherein a gas containing the element hydrogen is supplied.

15. The substrate processing method according to claim 14, wherein after supplying a gas containing the hydrogen element, a gas containing a group 14 element is supplied.

16. The substrate processing method according to claim 15, wherein a predetermined number of cycles are performed in which (a), (b), and (c) are performed in that order, followed by (d), (b), and (c) being performed in that order.

17. The substrate processing method according to claim 14, wherein a predetermined number of cycles are performed in which (a), (b), and (c) are performed in that order, and then (d), (b), and (c) are performed in that order.

18. The substrate processing method according to claim 1, further comprising the step of supplying a gas containing a third halogen element before (e)(a).

19. The substrate processing method according to claim 1, further comprising the step of removing halogen elements remaining on the substrate before (f)(a).

20. A method for manufacturing a semiconductor device, comprising: (a) supplying a first gas containing a group 14 element to form a first film containing the group 14 element preferentially on the group 14 element exposed surface at the bottom of a recess in a substrate; (b) supplying a second gas containing a group 14 element to form a second film containing the group 14 element in the recess of the substrate; (c) supplying a third gas containing a second halogen element to etch a portion of the second film; and (d) removing the second halogen element remaining on the substrate after (c).

21. A program that causes a processing device to perform the following steps by computer: (a) supplying a first gas containing a group 14 element to form a first film containing the group 14 element preferentially on the group 14 element exposed surface at the bottom of a recess in a substrate; (b) supplying a second gas containing a group 14 element to form a second film containing the group 14 element in the recess of the substrate; (c) supplying a third gas containing a second halogen element to etch a portion of the second film; and (d) removing the second halogen element remaining on the substrate after (c).

22. A substrate processing apparatus comprising: a first gas supply system for supplying a first gas containing a group 14 element to a substrate; a second gas supply system for supplying a second gas containing a group 14 element to the substrate; a third gas supply system for supplying a third gas containing a second halogen element to the substrate; and a control unit configured to control the first gas supply system, the second gas supply system and the third gas supply system to perform the following: (a) supplying the first gas to form a first film containing the group 14 element preferentially on the group 14 element exposed surface at the bottom of a recess in the substrate; (b) supplying the second gas to form a second film containing the group 14 element in the recess in the substrate; (c) supplying the third gas to etch a portion of the second film; and (d) after (c), removing the second halogen element remaining on the substrate.

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