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

Abstract

To provide a technique capable of improving uniformity of a film formed on a surface of a substrate.SOLUTION: A method of processing a substrate includes performing a first cycle of forming a layer containing a first element and a second element, the first cycle including performing: (a) supplying a first raw material gas containing the first element to a substrate including a recess on a surface of the substrate; (b) supplying a first adsorption inhibitor gas to the substrate; (c) supplying a second raw material gas containing the second element, different from the first element, to the substrate; and (d) supplying a reactant gas to the substrate, where a functional group formed on the substrate in (a) and (b) inhibits adsorption of the second raw material gas on the substrate, and where in at least a part of (c), the second raw material gas is supplied to the substrate on which the first raw material gas and the first adsorption inhibitor gas are adsorbed.SELECTED DRAWING: Figure 4

Description

Technical Field

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

Background Art

[0002] As one step of a substrate processing step (a semiconductor device manufacturing step), a film may be formed on the surface of a substrate using a substance that inhibits the adsorption of other substances to the substrate (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technique capable of improving the uniformity of a film formed on the surface of a substrate.

Means for Solving the Problems

[0005] According to one aspect of the present disclosure, (a) a step of supplying a first source gas having a first element to a substrate having recesses on its surface; (b) a step of supplying a first adsorption-inhibiting gas to the substrate; (c) a step of supplying a second source gas having a second element different from the first element to the substrate; (d) a step of supplying a reaction gas to the substrate; are performed to have a first cycle of forming a layer containing the first element and the second element, the functional groups formed on the substrate in (a) and (b) inhibit the adsorption of the second source gas onto the substrate, In at least a part of (c), a technique is provided in which the second source gas is supplied to the substrate on which the first source gas and the first adsorption-inhibiting gas are adsorbed.

Advantages of the Invention

[0006] According to the present disclosure, it becomes possible to improve the uniformity of the film formed on the surface of the substrate.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0008] <One Aspect of the Present Disclosure> Hereinafter, one aspect of the present disclosure will be mainly described with reference to FIGS. 1 to 4, FIGS. 5(a) to 5(c). 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) Configuration of Substrate Processing Apparatus As shown in FIG. 1, the processing furnace 202 has a heater 207 as a temperature adjustment unit (heating unit). The heater 207 also functions as an activation mechanism (excitation unit) for activating (exciting) the gas with heat.

[0010] Inside the heater 207, a reaction tube 203 is disposed. Below the reaction tube 203, a manifold 209 is disposed, and an O-ring 220a as a seal member is provided between the manifold 209 and the reaction tube 203. Mainly, the reaction tube 203 and the manifold 209 constitute a processing container (reaction container). A processing chamber 201 is formed inside the processing container. The processing chamber 201 is configured to be able to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed in this processing chamber 201.

[0011] Inside the processing chamber 201, nozzles 249a to 249c as the first to third supply units are respectively provided. The nozzles 249a to 249c are also respectively referred to as the first to third nozzles. Gas supply pipes 232a to 232c are respectively connected to the nozzles 249a to 249c.

[0012] In the gas supply pipes 232a to 232c, mass flow controllers (MFCs) 241a to 241c, which are flow rate controllers (flow rate control units), and valves 243a to 243c, which are on-off valves, are respectively provided in order from the upstream side of the gas flow. On the downstream side of the valve 243a of the gas supply pipe 232a, gas supply pipes 232d and 232f are respectively connected. On the downstream side of the valve 243b of the gas supply pipe 232b, gas supply pipes 232e and 232g are respectively connected. On the downstream side of the valve 243c of the gas supply pipe 232c, a gas supply pipe 232h is connected. In the gas supply pipes 232d to 232h, MFCs 241d to 241h and valves 243d to 243h are respectively provided in order from the upstream side of the gas flow.

[0013] As shown in FIG. 2, the nozzles 249a to 249c are respectively provided in the space between the inner wall of the reaction tube 203 and the wafer 200. The nozzles 249a and 249c are arranged on both sides of a straight line L passing through the center of the nozzle 249b and the exhaust port 231a. Gas supply holes 250a to 250c for supplying gas toward the wafer 200 are provided in each of the nozzles 249a to 249c. A plurality of gas supply holes 250a to 250c are provided from the lower part to the upper part of each of the nozzles 249a to 249c.

[0014] The first precursor gas is supplied into the processing chamber 201 through the gas supply pipe 232a, the MFC 241a, the valve 243a, and the nozzle 249a.

[0015] The second precursor gas is supplied into the processing chamber 201 through the gas supply pipe 232b, the MFC 241b, the valve 243b, and the nozzle 249b.

[0016] The reactant is supplied into the processing chamber 201 through the gas supply pipe 232c, MFC 241c, valve 243c, and nozzle 249c.

[0017] The first inhibitor is supplied into the processing chamber 201 through the gas supply pipe 232d, MFC 241d, valve 243d, gas supply pipe 232a, and nozzle 249a. Here, the first inhibitor is a gas that inhibits the adsorption of the second source gas onto the wafer 200.

[0018] The second inhibitor is supplied into the processing chamber 201 through the gas supply pipe 232e, MFC 241e, valve 243e, gas supply pipe 232b, and nozzle 249b. Here, the second inhibitor is a gas that inhibits the adsorption of the first source gas onto the wafer 200.

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

[0020] Primarily, the first source gas supply system is constituted by the gas supply pipe 232a, MFC 241a, and valve 243a. Primarily, the second source gas supply system is constituted by the gas supply pipe 232b, MFC 241b, and valve 243b. Primarily, the reactant gas supply system is constituted by the gas supply pipe 232c, MFC 241c, and valve 243c. Primarily, the first inhibitor gas supply system is constituted by the gas supply pipe 232d, MFC 241d, and valve 243d. Primarily, the second inhibitor gas supply system is constituted by the gas supply pipe 232e, MFC 241e, and valve 243e. Primarily, the inert gas supply system is constituted by the gas supply pipes 232f to 232h, MFCs 241f to 241h, and valves 243f to 243h. The nozzles connected to the gas supply pipes constituting the above various supply systems may be included in their respective supply systems.

[0021] Among the various supply systems described above, any one or all of the supply systems may be configured as an integrated supply system 248 in which valves 243a to 243h, MFCs 241a to 241h, etc. are integrated. The integrated supply system 248 is connected to each of the gas supply pipes 232a to 232h, and the supply operation of various substances (various gases) into the gas supply pipes 232a to 232h, that is, the opening and closing operations of the valves 243a to 243h and the flow rate adjustment operations by the MFCs 241a to 241h, etc. are configured to be controlled by a controller 121 described later.

[0022] An exhaust pipe 231 is connected to the lower part of the side wall of the reaction tube 203, and an exhaust port 231a for exhausting the atmosphere in the processing chamber 201 is provided. 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 regulation unit) are provided in the exhaust pipe 231, and a vacuum pump 246 as a vacuum exhaust device is connected via them. The APC valve 244 can perform vacuum exhaust and stop of vacuum exhaust in the processing chamber 201 by opening and closing the valve with the vacuum pump 246 operating. The APC valve 244 is further configured to be able to adjust the pressure in the processing chamber 201 by adjusting the valve opening degree based on the pressure information detected by the pressure sensor 245 with the vacuum pump 246 operating. Mainly, the exhaust pipe 231, the APC valve 244, and the pressure sensor 245 constitute an exhaust system. The vacuum pump 246 may be considered to be included in the exhaust system.

[0023] Below the manifold 209, a seal cap 219 is provided that can airtightly close the lower end opening of the manifold 209. On the upper surface of the seal cap 219, an O-ring 220b is provided as a seal member that contacts the lower end of the manifold 209. Below the seal cap 219, a rotation mechanism 267 is installed. The rotation shaft 255 of the rotation mechanism 267 passes through the seal cap 219 and is connected to the boat 217. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be vertically lifted 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 the wafer 200 into and out of the processing chamber 201 by lifting and lowering the seal cap 219.

[0024] Below the manifold 209, a shutter 219s is provided that can airtightly close the lower end opening of the manifold 209 in a state where the seal cap 219 is lowered and the boat 217 is carried out from the inside of the processing chamber 201. On the upper surface of the shutter 219s, an O-ring 220c is provided as a seal member that contacts the lower end of the manifold 209. The opening and closing operation (lifting and lowering operation, rotation 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, for example, 25 to 200 wafers 200 in a horizontal posture in multiple stages. Note that the notation of a numerical range such as "25 to 200 sheets" in this specification means that the lower limit value and the upper limit value are included in that range. Therefore, for example, "25 to 200 sheets" means "25 sheets or more and 200 sheets or less". The same applies to other numerical ranges. Below the boat 217, heat insulating plates 218 made of a heat resistant material such as quartz or SiC are supported in multiple stages.

[0026] Inside the reaction tube 203, a temperature sensor 263 as a temperature detector is installed. By adjusting the power supplied to the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature inside the processing chamber 201 or on the wafer 200 can be set to a desired temperature distribution. The temperature sensor 263 is provided 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. In addition, an external storage device 123 can be connected to the controller 121. Note that the substrate processing apparatus may be configured to include one control unit, or may be configured to include a plurality of control units. That is, control for performing a processing sequence described later may be performed using one control unit, or may be performed using a plurality of control units. Further, the plurality of control units may be configured as a control system connected to each other by a wired or wireless communication network, and control for performing a processing sequence described later may be performed by the entire control system. When the term "control unit" is used in this specification, it may include one control unit, a plurality of control units, or a control system constituted by a plurality of control units.

[0028] The storage device 121c is composed of, for example, a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), etc. In the storage device 121c, a control program for controlling the operation of the substrate processing apparatus, a process recipe in which procedures and conditions for substrate processing described later, etc. are recorded and stored in a readable manner. The process recipe is a combination of procedures in substrate processing described later to be executed by the controller 121 on the substrate processing apparatus so as to obtain a predetermined result, and functions as a program. Hereinafter, the process recipe, the control program, etc. are collectively referred to simply as a program. Also, the process recipe is simply referred to as a recipe. When the term "program" is used in this specification, it may include only the recipe alone, only the control program alone, or both of them. The RAM 121b is configured as a memory area (work area) that temporarily holds programs, data, etc. read by the CPU 121a.

[0029] The I / O port 121d is connected to the above-described 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, etc.

[0030] The CPU 121a is configured to read out and execute a control program from the storage device 121c, and to be able to read out a recipe from the storage device 121c in response to an input of an operation command from the input / output device 122 or the like. The CPU 121a is configured to control the flow rate adjustment operations of various substances (various gases) by the MFCs 241a to 241h, the opening and closing operations of the valves 243a to 243h, the opening and closing operation of the APC valve 244, the pressure adjustment operation by the APC valve 244 based on the pressure sensor 245, the startup 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 operations of the boat 217 by the rotation mechanism 267, the lifting and lowering operations of the boat 217 by the boat elevator 115, the opening and closing operations of the shutter 219s by the shutter opening and closing mechanism 115s, etc., in accordance with the content of the read-out recipe.

[0031] The controller 121 can be configured by installing the above-described program recorded and stored in the external storage device 123 into a computer. The external storage device 123 includes, for example, magnetic disks such as HDDs, optical disks such as CDs, magneto-optical disks such as MOs, semiconductor memories such as USB memories and SSDs, and the like. 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 medium" 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. Note that the program may be provided to the computer without using the external storage device 123, but by using communication means such as the Internet or a dedicated line.

[0032] (2) Substrate processing step Using the above-described substrate processing apparatus, as one step in the manufacturing process of a semiconductor device, a method for processing a substrate, that is, an example of a processing sequence for forming a film on a wafer 200 as a substrate having recesses such as trenches, grooves, and holes which are three-dimensional structures on its surface will be mainly described with reference to FIGS. 4, 5(a) to 5(c). In the following description, the operations of each part constituting the substrate processing apparatus are controlled by the controller 121.

[0033] In the processing sequence of this embodiment, (a) A step of supplying a first source gas containing a first element to the wafer 200 having recesses on its surface, (b) A step of supplying a first adsorption-inhibiting gas to the wafer 200, (c) A step of supplying a second source gas containing a second element different from the first element to the wafer 200, (d) A step of supplying a reaction gas to the wafer 200 are performed to have a first cycle of forming a layer containing the first element and the second element. The functional groups formed on the wafer 200 in (a) and (b) inhibit the adsorption of the second source gas onto the wafer 200. In at least a part of (c), the second source gas is supplied to the wafer 200 on which the first source gas and the first adsorption-inhibiting gas are adsorbed.

[0034] As shown in FIG. 4, in this embodiment, the case where the cycles of performing (a), (b), (c), and (d) in this order are performed a predetermined number of times (n times, where n is an integer of 1 or more) will be described.

[0035] As shown in FIG. 4, in this embodiment, the case where the second source gas is supplied to the wafer 200 on which the first source gas and the first adsorption-inhibiting gas are adsorbed in all of (c) will be described.

[0036] In this specification, the above-described processing sequence may be shown as follows for convenience. The same notation will be used in the description of the following modification examples and other embodiments.

[0037] (First source gas → First adsorption inhibitor gas → Second source gas → Reaction gas) × n In this specification, the "→" in "First source gas → First adsorption inhibitor gas" etc. indicates that a purge process for purging the inside of the processing chamber 201 is performed.

[0038] The term "wafer" as used in this specification may mean the wafer itself or a laminate of the wafer and a predetermined layer or film formed on its surface. The term "surface of the wafer" as used in this specification may mean the surface of the wafer itself or the surface of a predetermined layer or the like formed on the wafer. When it is described in this specification that "a predetermined layer is formed on the wafer", it may mean directly forming a predetermined layer on the surface of the wafer itself or forming a predetermined layer on a layer or the like formed on the wafer. When the term "substrate" is used in this specification, it has the same meaning as when the term "wafer" is used.

[0039] The term "layer" as used in this specification includes at least either a continuous layer or a discontinuous layer. For example, a deposited layer may include a continuous layer, a discontinuous layer, or both of them.

[0040] In this specification, when describing that the first source gas, the first adsorption inhibitor gas, the second source gas, the second adsorption inhibitor gas, and the reaction gas are respectively adsorbed or react with the surface of the wafer 200, it includes not only the mode in which they adsorb or react with the surface of the wafer 200 as they are without decomposition, but also the mode in which they decompose and the intermediate generated by the desorption of its ligand reacts or adsorbs with the surface of the wafer 200.

[0041] (Wafer charge and boat load) A plurality of wafers 200 are loaded (wafer charge) into the boat 217. The shutter 219s is moved by the shutter opening / closing mechanism 115s, and the lower end opening of the manifold 209 is opened (shutter open). Thereafter, 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. In this way, as shown in FIG. 1, the wafers 200 are prepared (provided) in the processing chamber 201.

[0042] (Pressure adjustment and temperature adjustment) After the boat load is completed, the processing chamber 201, that is, the space where the wafers 200 are present, is evacuated (depressurized exhaust) by the vacuum pump 246 so as to reach a desired pressure (vacuum degree). At this time, the pressure in 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 wafers 200 in the processing chamber 201 are heated by the heater 207 so as to reach a desired processing temperature. At this time, the power supplied to the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the processing chamber 201 has a desired temperature distribution. Also, the rotation of the wafers 200 by the rotation mechanism 267 is started. The evacuation of the processing chamber 201, the heating of the wafers 200, and the rotation are all continuously performed until at least the processing of the wafers 200 is completed.

[0043] (Film formation process) Thereafter, the following steps A, B, C, and D are sequentially executed.

[0044] [Step A] In this step, a first source gas having a first element is supplied to the wafers 200 in the processing chamber 201, that is, the wafers 200 having recesses on their surfaces.

[0045] Specifically, open valve 243a and flow the first source gas into gas supply pipe 232a. The first source gas is adjusted in flow rate by MFC241a, supplied into processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, the first source gas is supplied to wafer 200 from the side of wafer 200 (first source gas supply). At this time, valves 243f to 243h may be opened to supply an inert gas into processing chamber 201 via each of nozzles 249a to 249c.

[0046] As the processing conditions when supplying the first source gas in this step, Processing temperature: 350 to 700 °C, preferably 500 to 600 °C Processing pressure: 1 to 10000 Pa, preferably 10 to 1333 Pa First source gas supply flow rate: 0.01 to 3 slm, preferably 0.1 to 1 slm First source gas supply time: 10 to 120 seconds, preferably 20 to 60 seconds Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm are exemplified.

[0047] Note that the processing temperature in this specification means the temperature of wafer 200 or the temperature in processing chamber 201, the processing pressure means the pressure in processing chamber 201. Also, the processing time means the time for which the processing is continued. Further, the supply flow rate means the flow rate of the gas supplied into processing chamber 201. Also, when 0 slm is included in the supply flow rate, 0 slm means the case where that substance (gas) is not supplied into processing chamber 201. These are the same in the following description.

[0048] Under the above processing conditions, by supplying the first source gas to the wafer 200, the first source gas can be adsorbed on the adsorption sites existing on the surface of the wafer 200 (see Fig. 5(a)). Specifically, thereby, the first source gas can be discontinuously adsorbed on at least a part of the upper surface and the inner surface (the side wall surface and the bottom surface inside the recess) of the recess (see Fig. 5(a)). More specifically, thereby, the first source gas can be discontinuously adsorbed on the entire surface from the opening side to the deep side of the recess. Note that on the upper surface and the inner surface of the recess on which the first source gas is adsorbed, a predetermined functional group of the first source gas is in an exposed state. Hereinafter, the "opening side of the recess" is referred to as the "opening side", and the "deep side of the recess" is referred to as the "deep side". In this specification, the "deep side of the recess" refers to a location and its peripheral region where the gas supplied to the wafer 200 hardly reaches, such as the bottom of the recess, as compared with the opening side.

[0049] As the first source gas, for example, a silane-based gas containing silicon (Si) as the first element can be used. As the silane-based gas, for example, a gas containing Si and a halogen, that is, a halosilane-based gas can be used. The halogen includes chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc. That is, the halosilane-based gas has at least one of halogen groups such as chloro (Cl) group, fluoro (F) group, bromo (Br) group, and iodo (I) group as a functional group.

[0050] As the first source gas, for example, chlorosilane-based gases such as monochlorosilane (SiH3Cl) gas, dichlorosilane (SiH2Cl2) gas, trichlorosilane (SiHCl3) gas, tetrachlorosilane (SiCl4) gas, hexachlorodisilane (Si2Cl6) gas, and octachlorotrisilane (Si3Cl8) gas can be used. As the first source gas, one or more of these can be used.

[0051] As the first source gas, in addition to chlorosilane-based gases, for example, fluorosilane-based gases such as tetrafluorosilane (SiF4) gas, trifluorosilane (SiHF3) gas, and difluorosilane (SiH2F2) gas, bromosilane-based gases such as tetrabromosilane (SiBr4) gas, tribromosilane (SiHBr3) gas, and dibromosilane (SiH2Br2) gas, and iodosilane-based gases such as tetraiodosilane (SiI4) gas, triiodosilane (SiHI3) gas, and diiodosilane (SiH2I2) gas can also be used. As the first source gas, one or more of these can be used.

[0052] Also, as the first source gas, for example, a gas having Si as the first element and an organic ligand can be used. Examples of the gas having Si and an organic ligand include aminosilane-based gases such as tetrakis(dimethylamino)silane (Si[N(CH3)2]4) gas, tris(dimethylamino)silane (Si[N(CH3)2]3H) gas, bis(diethylamino)silane (Si[N(C2H5)2]2H2) gas, bis(tert-butylamino)silane (SiH2[NH(C4H9)]2) gas, and (diisopropylamino)silane (SiH3[N(C3H7)2]) gas. Also, as the first source gas, a gas having Si as the first element and a hydrogen (H) group can be used. Examples of the gas having Si and an H group include monosilane (SiH4), disilane (Si2H6). As the first source gas, one or more of these can be used.

[0053] In addition to these, as the first source gas, for example, a gas containing Si and an alkyl group as an organic ligand, that is, an alkylsilane-based gas can also be used. The alkyl group may be linear or branched. Examples of the alkyl 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.

[0054] In addition, as the first element, for example, one or more of tungsten (W), titanium (Ti), molybdenum (Mo), tantalum (Ta), cobalt (Co), yttrium (Y), ruthenium (Ru), hafnium (Hf), zirconium (Zr), aluminum (Al), boron (B), gallium (Ga), indium (In), phosphorus (P), carbon (C), etc. can be used.

[0055] As the first source gas, for example, a gas containing a first element and a halogen element can be used. Examples of such gases include tungsten hexachloride (WCl6), tungsten hexafluoride (WF6), titanium tetrachloride (TiCl4), titanium tetrafluoride (TiF4), molybdenum pentachloride (MoCl5), molybdenum pentafluoride (MoF5), molybdenum dioxide dichloride (MoO2Cl2), molybdenum oxychloride tetrachloride (MoOCl4), tantalum pentachloride (TaCl5), tantalum pentafluoride (TaF5), cobalt difluoride (CoF2), cobalt dichloride (CoCl2), yttrium trifluoride (YF3), yttrium trichloride (YCl3), ruthenium trichloride (RuCl3), ruthenium trifluoride (RuF3), hafnium tetrachloride (HfCl4), hafnium tetrafluoride (HfF4), zirconium tetrachloride (ZrCl4), zirconium tetrafluoride (ZrF4), aluminum trichloride (AlCl3), aluminum trifluoride (AlF3), etc. can be used. Further, as the first gas, for example, boron trifluoride (BF3), boron trichloride (BCl3), gallium trifluoride (GaF3), gallium trichloride (GaCl3), indium trifluoride (InF3), indium trichloride (InCl3), phosphorus trifluoride (PF3), phosphorus pentafluoride (PF5), phosphorus trichloride (PCl3), phosphorus pentachloride (PCl5), carbon tetrafluoride (CF4), carbon tetrachloride (CCl4), trifluoromethane (CHF3), fluoromethane (CH3F), trichloromethane (CHCl3), chloromethane (CH3Cl), etc. can be used. As the first source gas, for example, a gas having a Br group with the first element and a gas having an I group with the first element can also be used.

[0056] In addition, as the first raw material gas, for example, a gas having a first element and an organic ligand, or a gas having a first element and a hydrogen group can be used. As the organic ligand, for example, an alkyl group, a cycloalkyl group, an alkoxide group, a phenyl group, or a cyclopentadienyl group can be used. As the first raw material gas, for example, hexadimethylaminoditungsten (W2[N(CH3)2]6), bistert-butylimidobisdimethylamidotungsten ((t-C4H9NH)2W=(Nt-C4H9)2), tetrakisethylmethylaminotitanium (Ti[N(C2H5)(CH3)]4), bisethylcyclopentadienylruthenium (Ru(CH2CH3)Cp)2), biscyclopentadienylruthenium (Ru(Cp)2), tetrakisethylmethylaminohafnium (Hf[N(CH3)(CH2CH3)]4), tetrakisdiethylaminohafnium (Hf[N(CH2CH3)2]4), tetrakisdimethylaminohafnium (Hf[N(CH3)2]4), trisdimethylaminocyclopentadienylhafnium ((Cp)Hf[N(CH3)2]3), tetrakisethylmethylaminozirconium (Zr[N(CH3)Cp]4), tetrakisdiethylaminozirconium (Zr[N(CH2CH3)2]4), tetrakisdimethylaminozirconium (Zr[N(CH3)2]4), trisdimethylaminocyclopentadienylzirconium ((Cp)Zr[N(CH3)2]3), trimethylaluminum (Al(CH3)3), boron (BH3), trimethylgallium (Ga(CH3)3), trimethylindium (In(CH3)3), phosphine (PH3), methane (CH4), etc. can be used.

[0057] As the inert gas, nitrogen (N2) gas, or noble gases such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, and xenon (Xe) gas can be used. As the inert gas, one or more of these can be used. This also applies to each step described later.

[0058] After adsorbing the first source gas on the surface of the wafer 200 (the upper surface and the inner surface of the recess), the valve 243a is closed to stop the supply of the first source gas into the processing chamber 201. Then, the inside of the processing chamber 201 is evacuated to remove gaseous substances and the like remaining in the processing chamber 201 from the processing chamber 201. At this time, the valves 243f to 243h are opened, and an inert gas is supplied 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, whereby the space where the wafer 200 is present, that is, the inside of the processing chamber 201 is purged (purging).

[0059] [Step B] After step A is completed, a first adsorption-inhibiting gas is supplied to the wafer 200 inside the processing chamber 201, that is, the wafer 200 after the first source gas is adsorbed on the inner surface of the recess.

[0060] Specifically, the valve 243d is opened, and the first adsorption-inhibiting gas is caused to flow into the gas supply pipe 232d. The flow rate of the first adsorption-inhibiting gas is adjusted by the MFC241d, supplied into the processing chamber 201 through the nozzle 249a, and exhausted from the exhaust port 231a. At this time, the first adsorption-inhibiting gas is supplied to the wafer 200 (first adsorption-inhibiting gas supply). At this time, the valves 243f to 243h may be opened to supply an inert gas into the processing chamber 201 through each of the nozzles 249a to 249c.

[0061] As the processing conditions for supplying the first adsorption-inhibiting gas in this step, Processing temperature: 400 to 900 °C, preferably 500 to 800 °C Processing pressure: 1 to 2666 Pa, preferably 10 to 1333 Pa First adsorption-inhibiting gas supply flow rate: 0.001 to 2 slm, preferably 0.01 to 1 slm First adsorption-inhibiting gas supply time: 1 to 40 seconds, preferably 2 to 20 seconds Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm is exemplified. Other processing conditions can be the same as those in supplying the first raw material gas in Step A.

[0062] It is preferable to make the supply time of the first adsorption-inhibiting gas shorter than the supply time of the first raw material gas in Step A. Also, it is preferable to make the processing pressure (total pressure) in this step lower than the processing pressure in Step A. Further, it is preferable to make the supply flow rate of the first adsorption-inhibiting gas less than the supply flow rate of the first raw material gas in Step A. Also, it is preferable to make the supply flow rate of the inert gas in this step larger than the supply flow rate of the inert gas in Step A.

[0063] Furthermore, it is preferable to make the partial pressure of the first adsorption-inhibiting gas lower than the partial pressure of the first raw material gas in Step A. It is preferable to make the molar fraction of the first adsorption-inhibiting gas smaller than the molar fraction of the first raw material gas in Step A.

[0064] By supplying the first adsorption-inhibiting gas to the wafer 200 under the above-described processing conditions, the first adsorption-inhibiting gas can be adsorbed on the adsorption sites present on the surface of the wafer 200 (see FIG. 5(b)). Specifically, thereby, the first adsorption-inhibiting gas can be discontinuously adsorbed on at least a part of the upper surface and the inner surface of the concave portion (see FIG. 5(b)). More specifically, thereby, the first adsorption-inhibiting gas can be preferentially adsorbed on the opening side rather than the deep part side (see FIG. 5(b)). Note that on the upper surface and the inner surface of the concave portion where the first adsorption-inhibiting gas is adsorbed, a predetermined functional group of the first adsorption-inhibiting gas is in an exposed state.

[0065] By performing Step A and Step B under the above-described processing conditions, the exposure amount of the first adsorption-inhibiting gas can be made smaller than the exposure amount of the first raw material gas. In this specification, the “exposure amount of gas” refers to the value obtained by time-integrating the partial pressure of the gas, and when the partial pressure of the gas can be regarded as constant, it can be obtained as the product of the partial pressure of the gas and the supply time of the gas.

[0066] By performing Steps A and B under the above processing conditions, the amount of the first adsorption-inhibiting gas adsorbed on the deep side can be made less than the amount of the first source gas adsorbed on the deep side (see Fig. 5(b)).

[0067] As the first adsorption-inhibiting gas, a halogen-containing gas containing at least one of Cl, F, Br, and I can be used. The halogen-containing gas has, as a functional group, at least one of halogen groups such as a Cl group, an F group, a Br group, and an I group. As the first adsorption-inhibiting gas, for example, simple gases of halogen elements such as fluorine (F2) gas, chlorine (Cl2) gas, bromine (Br2) gas, and iodine (I2) gas, interhalogen compounds such as chlorine trifluoride (ClF3) gas, bromine chloride (BrCl) gas, iodine chloride (ICl) gas, iodine pentafluoride (IF5) gas, bromine trifluoride (BrF3) gas, and iodine bromide (IBr) gas, hydrogen halide compounds such as hydrogen chloride (HCl) gas, hydrogen fluoride (HF) gas, hydrogen bromide (HBr) gas, and hydrogen iodide (HI) gas, or a gas obtained by combining these gases can be used.

[0068] In addition, as the first adsorption-inhibiting gas, a gas containing an organic compound can be used. As the gas containing an organic compound, a gas containing at least any one selected from the group consisting of an ether compound, a ketone compound, an amine compound, an organic hydrazine compound, and a compound having a cyclic structure in its molecular structure can be used. As the gas containing an ether compound, a gas containing at least any one of dimethyl ether, diethyl ether, methyl ethyl ether, propyl ether, isopropyl ether, furan, tetrahydrofuran, pyran, tetrahydropyran, etc. can be used. As the gas containing a ketone compound, a gas containing at least any one of dimethyl ketone, diethyl ketone, methyl ethyl ketone, methyl propyl ketone, etc. can be used. As the gas containing an amine compound, a gas containing at least any one of methylamine compounds such as monomethylamine, dimethylamine, trimethylamine, ethylamine compounds such as monoethylamine, diethylamine, triethylamine, and methylethylamine compounds such as dimethylethylamine, methyldiethylamine can be used. As the gas containing an organic hydrazine compound, a gas containing at least any one of methylhydrazine-based gases such as monomethylhydrazine, dimethylhydrazine, trimethylhydrazine, etc. can be used. As the gas containing a compound having a cyclic structure, a gas having a cyclic structure containing at least any one of cycloalkyl groups such as methoxycyclopentane, anisole, trimethylene oxide, etc., a benzene ring structure, and carbon in its molecular structure can be used. As the first adsorption-inhibiting gas, one or more of these can be used. An alkyl group-containing gas containing an alkyl group can also be used. As the first adsorption-inhibiting gas, methane (CH4) gas, ethane (C2H6) gas, propane (C3H8) gas, etc. can be used.

[0069] As the first adsorption-inhibiting gas, it is preferable to use a gas not containing the first element.

[0070] The molecular radius of the first adsorption-inhibiting gas used in this step is preferably smaller than the molecular radius of the first source gas used in step A.

[0071] After adsorbing the first inhibiting gas on the surface of the wafer 200 (the upper surface and the inner surface of the recess), the valve 243d is closed, and the supply of the first inhibiting gas into the processing chamber 201 is stopped. Then, the inside of the processing chamber 201 is evacuated, and gaseous substances and the like remaining in the processing chamber 201 are removed from the processing chamber 201. At this time, the valves 243f to 243h are opened, and an inert gas is supplied 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, whereby the space where the wafer 200 is present, that is, the inside of the processing chamber 201 is purged (purging).

[0072] [Step C] After step B is completed, a second source gas having a second element different from the first element is supplied to the wafer 200 in the processing chamber 201, that is, the wafer 200 after the first source gas and the first adsorption-inhibiting gas are adsorbed on the upper surface and the inner surface of the recess.

[0073] Specifically, the valve 243b is opened, and the second source gas is flowed into the gas supply pipe 232b. The flow rate of the second source gas is adjusted by the MFC241b, supplied into the processing chamber 201 through the nozzle 249b, and exhausted from the exhaust port 231a. At this time, the second source gas is supplied to the wafer 200 (second source gas supply). At this time, the valves 243f to 243h may be opened, and an inert gas may be supplied into the processing chamber 201 through each of the nozzles 249a to 249c.

[0074] As the processing conditions when supplying the second source gas in this step, Processing temperature: 400 to 900 °C, preferably 500 to 800 °C Processing pressure: 1 to 5000 Pa, preferably 10 to 1333 Pa Second source gas supply flow rate: 0.01 to 2 slm, preferably 0.1 to 1 slm Second raw material gas supply time: 5 to 50 seconds, preferably 6 to 30 seconds Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm is exemplified. Other processing conditions can be the same as those in step A when supplying the first raw material gas.

[0075] Here, it is preferable that the second raw material gas supply time is longer than the first adsorption inhibitor gas supply time in step B. It is preferable that the processing pressure in this step is higher than the processing pressure in step B. It is preferable that the second raw material gas supply flow rate is larger than the first adsorption inhibitor gas supply flow rate in step B. Also, it is preferable that the inert gas supply flow rate in this step is less than the inert gas supply flow rate in step B.

[0076] Furthermore, it is preferable that the partial pressure of the second raw material gas is higher than the partial pressure of the first adsorption inhibitor gas in step B. It is preferable that the mole fraction of the second raw material gas is larger than the mole fraction of the first adsorption inhibitor gas in step B.

[0077] By performing step B and step C under the above-described processing conditions, the exposure amount of the second raw material gas can be made larger than the exposure amount of the first adsorption inhibitor gas.

[0078] By supplying the second raw material gas to the wafer 200 under the above-described processing conditions, the second raw material gas can be adsorbed onto the portions of the surface of the wafer 200 where the first raw material gas and the first adsorption inhibitor gas are not adsorbed, that is, the adsorption sites remaining on the surface of the wafer 200 (see FIG. 5(c)).

[0079] Here, the first source gas and the first adsorption-inhibiting gas are gases that inhibit the adsorption of the second source gas onto the wafer 200. Specifically, the functional groups contained in the first source gas or the first adsorption-inhibiting gas and formed (exposed) on the upper surface and the inner surface of the concave portion inhibit the adsorption of the second source gas onto the wafer 200 (the upper surface and the inner surface of the concave portion). As a result, as shown in FIG. 5(c), the second source gas does not adsorb onto the first source gas and the first adsorption-inhibiting gas on the surface of the wafer 200. Therefore, by adjusting the processing conditions of step A or step B and controlling the amount of the first source gas and the first adsorption-inhibiting gas adsorbed onto the wafer 200, the amount of the second source gas adsorbed onto the wafer 200 can be controlled. Here, in this specification, "the second source gas does not adsorb onto the first source gas and the first adsorption-inhibiting gas" includes not only the case where the second source gas does not adsorb onto the first source gas and the first adsorption-inhibiting gas at all, but also the case where an extremely small amount of the second source gas adsorbs onto the first source gas and / or the first adsorption-inhibiting gas. For example, it is the case where the second source gas adsorbs onto about 1% of the first source gas and / or the first adsorption-inhibiting gas among the first source gas and / or the first adsorption-inhibiting gas on the wafer 200, and preferably includes the case where the second source gas adsorbs onto 1% or less of the first source gas and / or the first adsorption-inhibiting gas.

[0080] By performing steps A to C, the first source gas, the first adsorption-inhibiting gas, and the second source gas can be adsorbed onto the adsorption sites provided on the surface of the wafer 200, and a layer containing the first element and the second element (hereinafter, may be referred to as the first layer) can be formed. In other words, a first layer doped with the second element can be formed.

[0081] By performing step B and step C under the above-described processing conditions, the amount of the second source gas adsorbed on the deep part side can be made larger than the amount of the first adsorption-inhibiting gas adsorbed on the deep part side.

[0082] Here, as the second element, an element that is not contained in the first raw material gas among the elements exemplified as the first element, that is, an element different from the first element can be used. Further, as the second raw material gas, for example, a gas containing the second element among the gases exemplified as the first raw material gas, for example, a gas containing the second element and a halogen element, a gas containing the second element and an organic ligand, a gas containing the second element and an H group, etc. can be used.

[0083] When a hydrophilic functional group is formed on the wafer 200 in steps A and B, it is preferable to use, as the second raw material gas in step C, a gas (hydrophilic gas) containing a hydrophilic functional group in its molecular structure. Here, the hydrophilic functional group is a functional group in which a partial charge is likely to be generated due to the bias of the electron distribution in the molecular structure. Also, when a hydrophobic functional group is formed on the wafer 200 in steps A and B, it is preferable to use, as the second raw material gas in step C, a gas (hydrophobic gas) containing a hydrophobic functional group in its molecular structure. Here, the hydrophobic functional group is a functional group in which a partial charge is unlikely to be generated.

[0084] After adsorbing the second raw material gas on the surface (inner surface of the concave portion) of the wafer 200, the valve 243b is closed to stop the supply of the second raw material gas into the processing chamber 201. Then, the inside of the processing chamber 201 is evacuated to remove gaseous substances and the like remaining in the processing chamber 201 from the processing chamber 201. At this time, the valves 243f to 243h are opened, and an inert gas is supplied 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, whereby the space where the wafer 200 exists, that is, the inside of the processing chamber 201 is purged (purged).

[0085] [Step D] After step C is completed, a reaction gas is supplied to the wafer 200 in the processing chamber 201, that is, the wafer 200 after adsorbing the first raw material gas, the first adsorption-inhibiting gas, and the second raw material gas on the upper surface and the inner surface of the concave portion.

[0086] Specifically, open valve 243c and flow the reaction gas into gas supply pipe 232c. The reaction gas is adjusted in flow rate by MFC241c, supplied into processing chamber 201 via nozzle 249c, and exhausted from exhaust port 231a. At this time, the reaction gas is supplied to wafer 200 (reaction gas supply). At this time, valves 243f to 243h may be opened to supply an inert gas into processing chamber 201 via each of nozzles 249a to 249c.

[0087] As processing conditions when supplying the reaction gas in this step, Processing pressure: 1 to 4000 Pa, preferably 10 to 1000 Pa Reaction gas supply flow rate: 0.1 to 10 slm, preferably 1 to 5 slm Reaction gas supply time: 1 to 120 seconds, preferably 10 to 60 seconds are exemplified. Other processing conditions can be the same as those when supplying the first raw material gas in step A.

[0088] By supplying the reaction gas to wafer 200 under the above-described processing conditions, at least a part of the first layer formed on the inner surface of the concave portion reacts with the reaction gas and is modified. As a result, a modified layer of the first layer (hereinafter, may be referred to as the second layer) is formed on the inner surface of the concave portion. When forming the second layer, it is preferable that the reaction gas removes (desorbs) at least a part of the functional groups formed on wafer 200 in step B from the first layer by a chemical reaction. The removed functional groups are discharged from within processing chamber 201. Thereby, the second layer becomes a layer with fewer impurities than the first layer formed in step C.

[0089] For example, as the reaction gas, a gas containing, for example, a reducing gas, an oxidizing gas, a nitriding gas, a sulfiding gas, a selenizing gas, a tellurizing gas, etc. can be used. As the reaction gas, one or more of these can be used.

[0090] As the reducing gas, for example, one or more of gases including hydrogen (H2) gas, deuterium (D2) gas, borane (BH3) gas, diborane (B2H6) gas, carbon monoxide (CO) gas, ammonia (NH3) gas, monosilane (SiH4) gas, disilane (Si2H6) gas, trisilane (Si3H8) gas, monogermane (GeH4) gas, digermane (Ge2H6), etc. can be used. Further, as the reaction gas, for example, an oxidizing gas containing oxygen (O) can be used. As the oxidizing gas, for example, one or more of gases including oxygen (O2), ozone (O3), water vapor (H2O), a mixed gas of H2 and O2, hydrogen peroxide (H2O2), nitrous oxide (N2O), etc. can be used. As the nitriding gas, for example, one or more of hydrogen nitride-based gases such as ammonia (NH3) gas, diazene (N2H2) gas, hydrazine (N2H4) gas, N3H8 gas, etc. can be used. As the sulfiding gas, for example, gases containing sulfane (H2S), disulfane (H2S2), diammonium sulfide ((NH4)2S), dimethyl sulfide ((CH3)2S), etc. can be used. As the sulfiding gas, one or more of these can be used. As the seleniding gas, for example, gases containing selane (H2Se), diselane (H2Se2), dimethyl selenide ((CH3)2Se), etc. can be used. As the seleniding gas, one or more of these can be used. As the telluriding gas, for example, gases containing tellane (H2Te), ditellane (H2Te2), dimethyl telluride ((CH3)2Te), etc. can be used. As the telluriding gas, one or more of these can be used.

[0091] After changing the first layer formed on the surface of the wafer 200 (the inner surface of the concave portion) to the second layer, the valve 243c is closed, and the supply of the reaction gas into the processing chamber 201 is stopped. Then, the inside of the processing chamber 201 is evacuated, and gaseous substances and the like remaining in the processing chamber 201 are removed from the processing chamber 201. At this time, the valves 243f to 243h are opened, and an inert gas is supplied 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, whereby the space where the wafer 200 exists, that is, the inside of the processing chamber 201 is purged (purged).

[0092] [Performed a predetermined number of times] By performing the above steps A to D non-simultaneously, that is, in this order without synchronization, n cycles (n is an integer of 1 or more) are performed, and it becomes possible to form a film having a desired composition on the surface of the wafer 200 (the inner surface of the concave portion). For example, when a silane-based gas is used as the first source gas and a nitriding gas is used as the reaction gas, a silicon nitride film (SiN film) is formed on the surface of the wafer 200. It is preferable to repeat the above cycle a plurality of times until the film thickness of the film formed by laminating the second layer with the thickness of the second layer formed per cycle being thinner than the desired film thickness becomes the desired film thickness. Thereby, the thickness of the film formed in the concave portion can be further made uniform.

[0093] For example, when the reaction gas is a reducing gas, a film mainly composed of the first element and the second element can be formed on the wafer 200. For example, when any one of an oxidizing gas, a nitriding gas, a sulfiding gas, a seleniding gas, and a telluriding gas is used as the reaction gas, an oxide film containing the first element and the second element, a nitride film containing the first element and the second element, a sulfide film containing the first element and the second element, a selenide film containing the first element and the second element, and a telluride film containing the first element and the second element can be formed on the wafer 200.

[0094] (After purge and return to atmospheric pressure) After the film formation process is completed, an inert gas as a purge gas is supplied into the processing chamber 201 from each of the nozzles 249a to 249c, and exhausted from the exhaust port 231a. As a result, the inside of the processing chamber 201 is purged, and gases, reaction by-products, etc. remaining in the processing chamber 201 are removed from the processing chamber 201 (after purge). Thereafter, the atmosphere inside the processing chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure inside the processing chamber 201 is restored to normal pressure (atmospheric pressure restoration).

[0095] (Boat unloading and wafer discharge) 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 wafer 200 is carried out (boat unloading) from the lower end of the manifold 209 to the outside of the reaction tube 203 while being supported by the boat 217. 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 the processed wafer 200 is carried out to the outside of the reaction tube 203, it is taken out from the boat 217 (wafer discharge).

[0096] (3) Effects of this embodiment According to this embodiment, one or more of the following effects can be obtained.

[0097] (a) In steps A and B, the first source gas and the first adsorption-inhibiting gas are respectively supplied to the wafer 200 to form a functional group that inhibits the adsorption of the second source gas. Then, in at least a part of step C, the second source gas is supplied to the wafer 200 to form a layer containing the first element and the second element. Thereby, the difference in the adsorption amount of the second source gas between the opening side and the deep part side can be reduced, that is, the variation in the concentration of the second element in the film in the concave portion can be reduced. As a result, it becomes possible to improve the uniformity of the film formed on the surface of the wafer 200. These will be described below.

[0098] The gas supplied to the wafer 200 having the concave portion tends to reach (adsorb) the opening side and is less likely to reach the deep side. Therefore, also in step C, the second source gas is more likely to be adsorbed on the opening side than on the deep side. As a result, the uniformity of the film formed on the surface of the wafer 200 may decrease.

[0099] In this embodiment, in steps A and B, the first source gas and the first adsorption-inhibiting gas are respectively supplied to the wafer 200, and after forming a functional group that inhibits the adsorption of the second source gas on the wafer 200, in step C, the second source gas is supplied to the wafer 200 to form a layer containing the first element and the second element. That is, before starting step C, a functional group that inhibits the adsorption of the second source gas is formed more on the opening side than on the deep side. For this reason, it is possible to suppress the adsorption of the second source gas on the opening side while making it difficult to suppress the adsorption of the second source gas on the deep side. Thereby, the difference in the adsorption amount of the second source gas between the opening side and the deep side can be reduced. As a result, it becomes possible to improve the uniformity of the film formed on the surface of the wafer.

[0100] (b) It is preferable that the amount of the second source gas adsorbed on the deep side is larger than the amount of the first adsorption-inhibiting gas. Thereby, it is possible to make it difficult to suppress the adsorption of the second source gas on the deep side while suppressing the adsorption of the second source gas on the opening side. Thereby, the difference in the adsorption amount of the second source gas between the opening side and the deep side can be further reduced.

[0101] (c) It is preferable that the exposure amount of the second source gas is larger than the exposure amount of the first adsorption-inhibiting gas. Thereby, the amount of the second source gas adsorbed on the deep side can be made larger than the first adsorption-inhibiting gas adsorbed on the deep side. Thereby, the difference in the adsorption amount of the second source gas between the opening side and the deep side can be further reduced.

[0102] Note that it is preferable that at least one or more of 1 to 6 listed below are satisfied. Thereby, the exposure amount of the second source gas can be made larger than the exposure amount of the first adsorption-inhibiting gas. 1. When making the supply time of the second raw material gas in step C longer than the supply time of the first adsorption-inhibiting gas in step B 2. When making the processing pressure in step C higher than the processing pressure in step B 3. When making the supply flow rate of the second raw material gas in step C larger than the supply flow rate of the first adsorption-inhibiting gas in step B 4. When making the supply flow rate of the inert gas in step C smaller than the supply flow rate of the inert gas in step B 5. When making the partial pressure of the second raw material gas in the processing chamber 201 in step C higher than the partial pressure of the first adsorption-inhibiting gas in the processing chamber 201 in step B 6. When making the molar fraction of the second raw material gas in the gas in the processing chamber 201 in step C larger than the molar fraction of the first adsorption-inhibiting gas in step B

[0103] (d) It is preferable that the amount of the first adsorption-inhibiting gas adsorbed on the deep side is less than the amount of the first raw material gas. In such a case, on the deep side, it is difficult to suppress the adsorption of the second raw material gas, while on the opening side, the adsorption of the second raw material gas can be suppressed. Thereby, the difference in the adsorption amount of the second raw material gas between the opening side and the deep side can be made even smaller.

[0104] (e) By making the exposure amount of the first adsorption-inhibiting gas smaller than the exposure amount of the first raw material gas, the amount of the first adsorption-inhibiting gas adsorbed on the deep side can be made less than the amount of the first raw material gas adsorbed on the deep side, which is preferable. In such a case, on the deep side, it is difficult to suppress the adsorption of the second raw material gas, while on the opening side, the adsorption of the second raw material gas can be suppressed. As a result, the difference in the adsorption amount of the second raw material gas between the opening side and the deep side can be made even smaller.

[0105] Note that it is preferable to satisfy at least one or more of 7 to 12 listed below. Thereby, the exposure amount of the first adsorption-inhibiting gas can be made smaller than the exposure amount of the first raw material gas. 7. When making the first adsorption-inhibiting gas supply time in step B shorter than the first raw material gas supply time in step A 8. When making the processing pressure in step B lower than the processing pressure in step A 9. When making the first adsorption-inhibiting gas supply flow rate in step B less than the first raw material gas supply flow rate in step A 10. When making the inert gas supply flow rate in step B greater than the inert gas supply flow rate in step A 11. When making the partial pressure of the first adsorption-inhibiting gas in the processing chamber 201 in step B lower than the partial pressure of the first raw material gas in the processing chamber 201 in step A 12. When making the molar fraction of the first adsorption-inhibiting gas in the gas in the processing chamber 201 in step B smaller than the molar fraction of the first raw material gas in the gas in the processing chamber 201 in step A

[0106] (f) As described above, in step B, it is preferable that the adsorption amount of the first adsorption-inhibiting gas on the opening side is larger than that on the deep part side. From this, it is preferable that the first adsorption-inhibiting gas does not contain the first element. Thereby, a layer with a uniform amount of the first element can be formed over the entire recess.

[0107] (g) The reaction gas preferably removes the functional groups (functional groups derived from the first adsorption-inhibiting gas) formed on the wafer 200 in step B by a chemical reaction. Thereby, it is possible to suppress a decrease in the characteristics of the film due to the elements derived from the first adsorption-inhibiting gas being incorporated into the film.

[0108] (h) When the number of the second elements in the layer formed by the above cycle is smaller than the number of the first elements, the variation in the concentration of the second elements in the film in the recess, which is caused by the difference in the adsorption amount of the second raw material gas in the recess, tends to increase. Even in such a case, by using the technology of the present disclosure, the variation in the concentration of the second elements in the film in the recess can be surely reduced. Thereby, the uniformity of the film formed on the surface of the wafer 200 can be surely improved.

[0109] (i) By controlling the amount of the second source gas adsorbed on the wafer 200 according to the processing conditions in step A, the concentration of the second element in the film or layer can be controlled. Specifically, by adjusting the processing conditions in step A, such as controlling the amount of the first source gas supplied to the wafer 200, and controlling the amount of the second source gas adsorbed on the wafer 200, the concentration of the second element in the film or layer can be controlled.

[0110] (j) The molecular radius of the first adsorption-inhibiting gas is preferably smaller than the molecular radius of the first source gas. Thereby, the adsorption of the first adsorption-inhibiting gas to the wafer 200 by the functional groups formed on the wafer 200 in step A can be hardly inhibited. Therefore, the variation in the concentration of the second element in the film in the recess can be further reduced, and as a result, the uniformity of the film formed on the surface of the wafer 200 can be surely improved.

[0111] (k) When hydrophilic functional groups are formed on the wafer 200 in step A and step B, the second source gas supplied in step C is preferably a hydrophilic gas. For example, when a chlorosilane-based gas is supplied to the wafer 200 in step A and a gas containing Cl is supplied in step B, hydrophilic Cl groups (functional groups) are formed on the wafer 200. In such a case, in step C, it is preferable to supply a gas having a second element and a halogen element as the second gas that is hydrophilic to the wafer 200. Further, when hydrophobic functional groups are formed on the wafer 200 in step A and step B, the second source gas supplied in step C is preferably a hydrophobic gas. For example, when an aminosilane-based gas is supplied to the wafer 200 in step A and a gas containing an alkyl group is supplied in step B, hydrophobic alkyl groups (functional groups) are formed on the wafer 200. In such a case, in step C, it is preferable to supply a gas having a second element and an organic ligand, for example, as the second gas that is hydrophobic to the wafer 200. In these cases, the adsorption of the second source gas onto the wafer 200 is likely to be inhibited by the functional groups formed on the wafer 200 in step A and step B. Therefore, the variation in the concentration of the second element in the film within the recess can be reliably reduced, and as a result, the uniformity of the film formed on the surface of the wafer 200 can be reliably improved.

[0112] Note that the reactivity of a nitride gas with respect to the bond between a certain atom and a halogen group tends to be higher than the reactivity of the nitride gas with respect to the bond between a certain atom and an organic ligand. Therefore, for example, when the reaction gas is a nitride gas and a layer and a film containing a first element, a second element, and N are formed, the first source gas, the first adsorption-inhibiting gas, and the first source gas preferably contain a halogen group in their molecular structures. Thereby, it is possible to make it difficult for impurities derived from the organic ligand to be contained in the second layer or film.

[0113] (i) Similarly, even when arbitrarily selecting and using a predetermined substance (gaseous substance, liquid substance) from the above-described various raw material gases, various adsorption-inhibiting gases, various reaction gases, and various inert gases, the above-described effects can be obtained.

[0114] (4) Modification Example The processing sequence in this embodiment can be changed as in the following modification examples. These modification examples can be arbitrarily combined. Unless otherwise specified, the processing procedures and processing conditions in each step of each modification example can be the same as those in each step of the above-described processing sequence.

[0115] (Modification Example 1) As shown in FIG. 6(a) and the following processing sequence, the execution period of step B and the execution period of step C may be overlapped. After performing step A, steps B and C may be performed simultaneously, and then step D may be performed. Also, as shown in FIG. 6(b) and the following processing sequence, while partially overlapping the execution period of step B and the execution period of step C, the steps A, B, C, and D may be performed in this order. Also, as shown in FIG. 6(c) and the following processing sequence, while making the execution period of step B and the execution period of step C continuous, the steps A, B, C, and D may be performed in this order. Also, as shown in FIG. 6(d) and the following processing sequence, while overlapping the entire execution period of step B and a partial period of the execution period of step C, the steps may be performed in the order of A, C, B, D.

[0116] (First raw material gas → First adsorption-inhibiting gas + Second raw material gas → Reaction gas) × n (First raw material gas → First adsorption-inhibiting gas → First adsorption-inhibiting gas + Second raw material gas → Second raw material gas → Reaction gas) × n (First raw material gas → First adsorption-inhibiting gas | Second raw material gas → Reaction gas) × n (First raw material gas → Second raw material gas → First adsorption-inhibiting gas + Second raw material gas → Reaction gas) × n In this specification, the "|" in the above "First adsorption-inhibiting gas | Second source gas" indicates that no purging process for purging the inside of the processing chamber 201 is performed. It is preferable to use gases that do not react with each other as the first adsorption-inhibiting gas and the second source gas, respectively.

[0117] Also in this modified example, the same effects as those of the above-described aspect can be obtained. In this modified example, furthermore, the cycle time can be shortened to improve the productivity of the film-forming process. In FIGS. 6(d) and the processing sequence shown below, the second source gas is supplied to the wafer 200 on which the first source gas and the first adsorption-inhibiting gas are adsorbed only in a part of step C. Even in such a case, the same effects as those of the above-described aspect can be obtained. That is, it is preferable that the second source gas is supplied to the wafer 200 on which the first source gas and the first adsorption-inhibiting gas are adsorbed only in at least a part of step C.

[0118] (Modified Example 2) In at least a part of step A, the first source gas may be supplied to the wafer 200 on which the first adsorption-inhibiting gas is adsorbed. Specifically, as shown in FIG. 7(a) and the processing sequence shown below, after performing the step of supplying the first adsorption-inhibiting gas to the wafer 200, the steps of steps A, C, B, and D may be performed in this order. As shown in FIG. 7(b) and the processing sequence shown below, the steps may be performed in the order of steps B, A, C, D while overlapping the entire period of the execution period of step A and a part of the execution period of step B. As shown in FIG. 7(c) and the processing sequence shown below, steps A, B, and C may be performed simultaneously while overlapping the execution periods of steps A, B, and C, and then step D may be performed. As shown in FIG. 7(d) and the processing sequence shown below, after starting step A while overlapping a part of the execution period of step A and the entire execution periods of steps B and C, steps B and C may be performed simultaneously, and then step D may be performed.

[0119] (First adsorption-inhibiting gas → First source gas → First adsorption-inhibiting gas → Second source gas → Reaction gas) × n (First adsorption-inhibiting gas → First adsorption-inhibiting gas + First source gas → First adsorption-inhibiting gas → Second source gas → Reaction gas) × n (First source gas + First adsorption-inhibiting gas + Second source gas → Reaction gas) × n (First source gas → First source gas + First adsorption-inhibiting gas + Second source gas → First source gas → Reaction gas) × n

[0120] Also in this modified example, the same effects as those of the above-described aspect can be obtained. In this modified example, furthermore, the difference in the adsorption amount of the first source gas between the opening side and the deep part side can be reduced. As a result, the uniformity of the film in the concave portion can be improved.

[0121] (Modified Example 3) It may further include step E of supplying a second adsorption-inhibiting gas different from the first adsorption-inhibiting gas to the wafer 200, and in at least a part of step A, the first source gas may be supplied to the wafer 200 on which the second adsorption-inhibiting gas has been adsorbed. Specifically, as shown in FIG. 8 and the processing sequence described below, the steps may be performed in the order of steps E, A, B, C, and D.

[0122] (Second adsorption-inhibiting gas → First source gas → First adsorption-inhibiting gas → Second source gas → Reaction gas) × n

[0123] As the second adsorption-inhibiting gas, for example, one or more of the gases exemplified as the first source gas can be used.

[0124] In step E, the second adsorption-inhibiting gas is supplied to the wafer 200 in the processing chamber 201 by the second adsorption-inhibiting gas supply system.

[0125] As the processing conditions for supplying the second adsorption-inhibiting gas in this step, Processing temperature: 350 to 700 °C, preferably 500 to 600 °C Processing pressure: 1 to 10000 Pa, preferably 10 to 1333 Pa Second adsorption-inhibiting gas supply flow rate: 0.01 to 3 slm, preferably 0.1 to 1 slm Second adsorption-inhibiting gas supply time: 10 to 120 seconds, preferably 20 to 60 seconds Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm is exemplified.

[0126] By supplying the second adsorption-inhibiting gas to the wafer 200 under the above processing conditions, the second adsorption-inhibiting gas can be adsorbed on the adsorption sites present on the surface of the wafer 200. By supplying the second adsorption-inhibiting gas to the wafer 200 under the above processing conditions, the adsorption of the first source gas supplied in step A onto the wafer 200 can be inhibited.

[0127] When hydrophilic functional groups are formed on the wafer 200 in steps A, B, and step E, it is preferable to use a hydrophilic gas as the second source gas in step C. Also, when hydrophobic functional groups are formed on the wafer 200 in steps A, B, and step E, it is preferable to use a hydrophobic gas as the second source gas in step C.

[0128] Also in this modified example, the same effects as the above-described embodiment can be obtained. In this modified example, furthermore, the difference in the adsorption amount of the first source gas between the opening side and the deep part side can be reduced. As a result, the uniformity of the film in the recess can be improved.

[0129] Furthermore, in Modified Example 3, when hydrophilic functional groups are formed on the wafer 200 in steps A, B, and step E, when a hydrophilic second source gas is supplied, the hydrophilic functional groups tend to inhibit the adsorption of the second source gas onto the wafer 200. Similarly, when hydrophobic functional groups are formed on the wafer 200 in steps A, B, and step E, when a hydrophobic second source gas is supplied, the hydrophobic functional groups tend to inhibit the adsorption of the second source gas onto the wafer 200. Thereby, the variation in the concentration of the second element in the film in the recess can be surely reduced, and as a result, it becomes possible to surely improve the uniformity of the film formed on the surface of the wafer 200.

[0130] (Modification Example 4) It may further have a second cycle including step A and step D and not including step B. Specifically, as in FIG. 9 and the processing sequence shown below, after performing a first cycle in which each step of steps A to D is performed non-simultaneously in the order of steps A, B, C, D a predetermined number of times (n times, n is an integer of 1 or more), a second cycle including step A and step D and not including step B may be executed a predetermined number of times (m times, m is an integer of 1 or more).

[0131] (First source gas → First adsorption-inhibiting gas → Second source gas → Reaction gas) × n → (First source gas → Reaction gas) × m

[0132] Also in this modification example, the same effects as those of the above-described aspect can be obtained. In this modification example, further, a film can be formed by laminating a layer containing the first element and the second element and a layer containing the first element. Thereby, even when forming a film having a low concentration of the second element in the film, the concentration of the second element in the film can be controlled in more detail.

[0133] <Other Aspects of the Present Disclosure> As described above, the aspects of the present disclosure have been specifically described. However, the present disclosure is not limited to the above-described aspects, and various modifications can be made without departing from the gist thereof.

[0134] For example, in the above-described aspect, the case where a gas containing no first element is used as the first adsorption-inhibiting gas has been described as an example. However, the present disclosure is not limited to such an aspect. For example, a gas containing the first element can also be used as the first adsorption-inhibiting gas. Also in this case, at least some of the effects of the above-described aspect can be obtained.

[0135] For example, in the above-described embodiment, a halogen group is cited as an example of the hydrophilic functional group formed on the wafer 200 in steps A and B, and an alkyl group is cited as an example of the hydrophobic functional group for explanation. However, the present disclosure is not limited to such an embodiment. For example, the hydrophilic functional group formed on the wafer 200 in steps A and B may be an alkoxide group, an amino group, or the like, and the hydrophobic functional group may be a hydrogen group, a cycloalkyl group, a phenyl group, a cyclopentadienyl group, or the like. As the first source gas and the first adsorption-inhibiting gas, a gas having an alkoxide group, an amino group, or the like as a hydrophilic functional group, and a gas having a cycloalkyl group, a phenyl group, a cyclopentadienyl group, or the like as a hydrophobic functional group can be appropriately used. Even in these cases, the same effects as those in the above-described embodiment can be obtained.

[0136] For example, in the above-described embodiment, a gas having a halogen group is cited as an example of the hydrophilic second source gas, and a gas having an alkyl group or a hydrogen group is cited as an example of the hydrophobic second source gas for explanation. However, the present disclosure is not limited to such an embodiment. For example, a gas having an alkoxide group, an amino group, or the like can be appropriately used as the hydrophilic second source gas, and a gas having a cycloalkyl group, a phenyl group, a cyclopentadienyl group, or the like can be appropriately used as the hydrophobic second source gas.

[0137] The recipe used for each process is preferably prepared individually according to the process content, recorded and stored in the storage device 121c via a telecommunication 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 content from among the plurality of recipes recorded and stored in the storage device 121c. Thereby, it becomes possible to form films of various film types, composition ratios, film qualities, and film thicknesses with good reproducibility using a single substrate processing apparatus. In addition, the burden on the operator can be reduced, operation errors can be avoided, and each process can be started quickly.

[0138] The above recipe may be prepared not only when newly created, but also, for example, by modifying an existing recipe already installed in the substrate processing apparatus. When modifying the recipe, the modified recipe may be installed in the substrate processing apparatus via a telecommunication line or a recording medium on which the recipe is recorded. Alternatively, the input / output device 122 provided in the existing substrate processing apparatus may be operated to directly modify the existing recipe already installed in the substrate processing apparatus.

[0139] In the above aspect, an example of forming a film using a batch-type substrate processing apparatus that processes a plurality of substrates at a time has been described. The present disclosure is not limited to the above aspect, and can be suitably applied, for example, also when forming a film using a single-wafer type substrate processing apparatus that processes one or several substrates at a time. Further, in the above aspect, 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 aspect, and can be suitably applied also when forming a film using a substrate processing apparatus having a cold-wall type processing furnace. Further, in the above aspect, an example of activating a gas by heat has been described. However, the present disclosure is not limited thereto. For example, it can be suitably applied also when activating a gas by plasma generated inside or outside the processing chamber 201, or when activating a gas by irradiating the gas with electromagnetic waves using a lamp or the like.

[0140] Even when using these substrate processing apparatuses, each process can be performed under the same processing procedures and processing conditions as those in the above aspect and modified examples, and the same effects as those in the above aspect and modified examples can be obtained.

[0141] The above aspect and modified examples can be used in appropriate combinations. The processing procedures and processing conditions at this time can be, for example, the same as the processing procedures and processing conditions of the above aspect and modified examples.

Description of Reference Numerals

[0142] 200 Wafer (substrate)

Claims

1. (a) A step of supplying a first source gas having a first element to a substrate having a concave portion on its surface; (b) A step of supplying a first adsorption-inhibiting gas to the substrate; (c) A step of supplying a second source gas having a second element different from the first element to the substrate; (d) A step of supplying a reaction gas to the substrate; are performed, and it has a first cycle of forming a layer containing the first element and the second element, The functional groups formed on the substrate in (a) and (b) inhibit the adsorption of the second source gas onto the substrate, In at least a part of (c), the second source gas is supplied to the substrate on which the first source gas and the first adsorption-inhibiting gas are adsorbed. A substrate processing method.

2. The amount of the second source gas adsorbed on the deep side of the concave portion is made larger than the amount of the first adsorption-inhibiting gas. The substrate processing method according to Claim 1.

3. The exposure amount of the second source gas is made larger than the exposure amount of the first adsorption-inhibiting gas. The substrate processing method according to Claim 2.

4. The amount of the first adsorption-inhibiting gas adsorbed on the deep side of the concave portion is made smaller than the amount of the first source gas. The substrate processing method according to Claim 1.

5. The exposure amount of the first adsorption-inhibiting gas is made smaller than the exposure amount of the first source gas. The substrate processing method according to Claim 4.

6. The first adsorption-inhibiting gas does not contain the first element. The substrate processing method according to any one of Claims 1 to 5.

7. The reaction gas removes the functional groups formed on the substrate in (b) by a chemical reaction. The substrate processing method according to any one of Claims 1 to 5.

8. The number of the second element in the layer formed by the first cycle is smaller than the number of the first element. The substrate processing method according to any one of Claims 1 to 5.

9. The amount of the second source gas adsorbed on the substrate under the processing conditions of (a) is controlled. The substrate processing method according to any one of Claims 1 to 5.

10. The molecular radius of the first adsorption-inhibiting gas is smaller than the molecular radius of the first source gas. The substrate processing method according to any one of Claims 1 to 5.

11. The substrate processing method according to any one of Claims 1 to 5, wherein the following (i) or (ii) holds. (i) Hydrophilic functional groups are formed on the substrate in (a) and (b), and the second source gas is a hydrophilic gas. In (ii) (a) and (b), a hydrophobic functional group is formed on the substrate, and the second source gas is a hydrophobic gas.

12. In at least a part of (a), supplying the first source gas to the substrate on which the first adsorption-inhibiting gas is adsorbed. The substrate processing method according to any one of Claims 1 to 5.

13. (e) A step of supplying a second adsorption-inhibiting gas different from the first adsorption-inhibiting gas to the substrate. further comprising In at least a part of (a), supplying the first source gas to the substrate on which the second adsorption-inhibiting gas is adsorbed. The substrate processing method according to any one of Claims 1 to 5.

14. The substrate processing method according to Claim 13, wherein the following (i) or (ii) holds. (i) In (a), (b) and (e), a hydrophilic functional group is formed on the substrate, and the second source gas is a hydrophilic gas. (ii) In (a), (b) and (e), a hydrophobic functional group is formed on the substrate, and the second source gas is a hydrophobic gas.

15. Further having a second cycle including (a) and (d) and not including (b). The substrate processing method according to any one of Claims 1 to 5.

16. The reaction gas is a nitriding gas, The first source gas, the first adsorption-inhibiting gas and the first source gas contain a halogen element in their molecular structures. The substrate processing method according to any one of Claims 1 to 5.

17. (a) A step of supplying a first source gas having a first element to a substrate having recesses on its surface; (b) A step of supplying a first adsorption-inhibiting gas to the substrate; (c) A step of supplying a second source gas having a second element different from the first element to the substrate; (d) A step of supplying a reaction gas to the substrate; performing a first cycle for forming a layer containing the first element and the second element, The functional groups formed on the substrate in (a) and (b) inhibit the adsorption of the second source gas onto the substrate. In at least a part of (c), supplying the second source gas to the substrate on which the first source gas and the first adsorption-inhibiting gas are adsorbed. A method for manufacturing a semiconductor device.

18. A first source gas supply system for supplying a first source gas having a first element; A first adsorption-inhibiting gas supply system for supplying a first adsorption-inhibiting gas; A second source gas supply system for supplying a second source gas having a second element different from the first element; A reaction gas supply system for supplying a reaction gas; (a) a process of supplying the first source gas to a substrate having a concave portion on its surface; (b) a process of supplying the first adsorption-inhibiting gas to the substrate; (c) a process of supplying the second source gas to the substrate; (d) a process of supplying the reaction gas to the substrate; are performed to have a first cycle of forming a layer containing the first element and the second element, the functional groups formed on the substrate in (a) and (b) inhibit the adsorption of the second source gas onto the substrate, in at least a part of (c), a process of supplying the second source gas to the substrate on which the first source gas and the first adsorption-inhibiting gas are adsorbed, a control unit configured to be able to control the first source gas supply system, the first adsorption-inhibiting gas supply system, the second source gas supply system, and the reaction gas supply system so that the above is performed; A substrate processing apparatus having the above.

19. (a) a procedure of supplying a first source gas having a first element to a substrate having a concave portion on its surface; (b) a procedure of supplying a first adsorption-inhibiting gas to the substrate; (c) a step of supplying a second source gas having a second element different from the first element to the substrate; (d) a procedure of supplying a reaction gas to the substrate; are performed to have a first cycle of forming a layer containing the first element and the second element, the functional groups formed on the substrate in (a) and (b) inhibit the adsorption of the second source gas onto the substrate, in at least a part of (c), a procedure of supplying the second source gas to the substrate on which the first source gas and the first adsorption-inhibiting gas are adsorbed, A program for causing a computer to execute the above on a substrate processing apparatus.

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