SUBSTRATE PROCESSING METHOD, SEMICONDUCTOR DEVICE MANUFACTURING METHOD, PROGRAM, AND SUBSTRATE PROCESSING APPARATUS

Abstract

To provide a substrate processing method, an apparatus and a program for forming a film of a desired thickness on a substrate and a method for manufacturing a semiconductor device.SOLUTION: A substrate processing method includes the steps of forming a first film containing predetermined elements on a substrate by performing a first predetermined number of cycles including a step for forming a first layer containing the predetermined elements by supplying raw material gas containing the predetermined element to the substrate and a step for reforming the second layer by supplying reaction gas that reacts with the first layer under a first condition, and a step for forming a second film containing the predetermined elements on the substrate by performing a second predetermined number of cycles including a step for forming a third layer containing the predetermined elements by supplying raw material gas to the substrate and a step for reforming a fourth layer by supplying reaction gas under a second condition different from the first condition, thereby a film consisting of the first film and the second film and containing the predetermined elements is formed. The first and second conditions are that, a thickness of the reformed fourth layer is thinner than a thickness of the formed second layer.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] As one step in the manufacturing process of a semiconductor device, a process is sometimes performed in which a nitride film is formed on the surface of a substrate by performing a cycle including a step of supplying a raw material gas and a step of supplying a nitrogen-containing gas to the substrate (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-168644 A Summary of the Invention [Problem to be solved by the invention]

[0004] When forming a film on a substrate, there are cases where precision is required to achieve a desired film thickness.

[0005] The present disclosure provides techniques capable of forming a film of a desired thickness on a substrate. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, (a)(a-1) supplying a source gas containing a predetermined element to a substrate to form a first layer containing the predetermined element on the substrate; (a-2) supplying a reaction gas that reacts with the first layer to the substrate on which the first layer is formed, thereby modifying the first layer into a second layer containing the predetermined element; a first predetermined number of cycles under first conditions to form a first film containing the predetermined element on the substrate; (b)(b-1) supplying the source gas to the substrate to form a third layer containing the predetermined element on the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a second predetermined number of cycles under second conditions different from the first conditions to form a second film containing the predetermined element on the substrate; By carrying out the above steps, a film containing the predetermined element is formed, the film being composed of the first film and the second film, the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2); Technology is provided. Effect of the Invention

[0007] According to the present disclosure, it is possible to form a film of a desired thickness on a substrate. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in one embodiment of the present disclosure, showing a processing furnace portion in vertical cross section. [Diagram 2] FIG. 2 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in one embodiment of the present disclosure, showing a processing furnace portion in a cross-sectional view taken along line AA in FIG. [Diagram 3] FIG. 3 is a schematic configuration diagram of a controller of a substrate processing apparatus preferably used in one embodiment of the present disclosure, and is a block diagram showing a control system of the controller. [Figure 4] FIG. 4 is a flowchart showing a substrate processing process according to one embodiment of the present disclosure. [Diagram 5]Fig. 5(A) is a diagram showing a film formed by a substrate processing step according to an embodiment of the present disclosure, and Fig. 5(B) and Fig. 5(C) are diagrams showing a film formed by a comparative example of the substrate processing step according to an embodiment of the present disclosure. [Figure 6] FIG. 6 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus according to another embodiment of the present disclosure, showing a processing furnace portion in vertical cross section. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] <One aspect of the present disclosure> Hereinafter, one embodiment of the present disclosure will be described mainly with reference to Figures 1 to 5. Note that all of the drawings used in the following description are schematic, and the dimensional relationships of the elements, the ratios of the elements, etc. shown in the drawings do not necessarily match those in reality. Furthermore, the dimensional relationships of the elements, the ratios of the elements, etc. between multiple drawings do not necessarily match.

[0010] (1) Configuration of the substrate processing device 1, the process furnace 202 has a heater 207 as a heating system (temperature adjustment unit). The heater 207 is cylindrical and is installed vertically by being supported by a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) gas by heat.

[0011] A reaction tube 203 is disposed concentrically with the heater 207 inside the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed in a cylindrical shape with a closed upper end and an open lower end. A manifold 209 is disposed concentrically with the reaction tube 203 below the reaction tube 203. The manifold 209 is made of a metal material such as stainless steel (SUS) and is formed in a cylindrical shape with an open upper end and a closed lower end. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 and is configured to support the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a seal member. The reaction tube 203 is installed vertically like the heater 207. The reaction tube 203 and the manifold 209 mainly constitute a processing vessel (reaction vessel). A processing chamber 201 is formed in a cylindrical hollow portion of the processing vessel. The processing chamber 201 is configured to be capable of accommodating a wafer 200 as a substrate. In the processing chamber 201, processing of the wafer 200 is performed.

[0012] Nozzles 249a and 249b are provided in the processing chamber 201 so as to penetrate a sidewall of the manifold 209. Gas supply pipes (pipes) 232a and 232b are connected to the nozzles 249a and 249b, respectively.

[0013] Gas supply pipes 232a and 232b are provided with mass flow controllers (MFCs) 241a and 241b, which are flow rate controllers (flow rate control parts), and valves 243a and 243b, which are on-off valves, in order from the upstream side. Gas supply pipes 232c and 232d, which supply inert gas, are connected to the gas supply pipes 232a and 232b downstream of the valves 243a and 243b. Gas supply pipes 232c and 232d are provided with MFCs 241c and 241d and valves 243c and 243d, respectively, in order from the upstream side.

[0014] 2, the nozzles 249a and 249b are provided in a circular space between the inner wall of the reaction tube 203 and the wafers 200 in a plan view, along the inner wall of the reaction tube 203 from the lower part to the upper part, so as to rise upward in the loading direction of the wafers 200. Gas supply holes 250a and 250b, which are supply ports for supplying gas, are provided on the side surfaces of the nozzles 249a and 249b, respectively. A plurality of gas supply holes 250a and 250b are provided from the lower part to the upper part of the reaction tube 203.

[0015] A source gas containing a predetermined element is supplied from the gas supply pipe 232a into the processing chamber 201 via the MFC 241a, the valve 243a, and the nozzle 249a.

[0016] A reactive gas that reacts with the source gas is supplied from the gas supply pipe 232b into the processing chamber 201 via the MFC 241b, a valve 243b, and a nozzle 249b.

[0017] From the gas supply pipes 232c and 232d, an inert gas is supplied into the processing chamber 201 via the MFCs 241c and 241d, the valves 243c and 243d, the gas supply pipes 232a and 232b, and the nozzles 249a and 249b. When the inert gas supplied from the gas supply pipes 232c and 232d is supplied simultaneously with the source gas, the inert gas is used as a dilution gas for diluting the source gas.

[0018] A raw material gas supply system is mainly composed of the gas supply pipe 232a, the MFC 241a, and the valve 243a. A reactive gas supply system is mainly composed of the gas supply pipe 232b, the MFC 241b, and the valve 243b. The raw material gas supply system and the reactive gas supply system may be collectively referred to as a gas supply system. An inert gas supply system is mainly composed of the gas supply pipes 232c and 232d, the MFCs 241c and 241d, and the valves 243c and 243d. The inert gas supply system may be included in the gas supply system.

[0019] Any or all of the various supply systems described above may be configured as an integrated supply system 248 in which the valves 243a-243d and the MFCs 241a-241d are integrated. The integrated supply system 248 is connected to the gas supply pipes 232a-232d, and the supply operation of various gases into the gas supply pipes 232a-232d, i.e., the opening and closing operation of the valves 243a-243d and the flow rate adjustment operation by the MFCs 241a-241d, are controlled by a controller 121, which will be described later. The integrated supply system 248 is configured as an integrated or separate type integrated unit, and can be attached and detached to and from the gas supply pipes 232a-232d, etc., in units of integrated units, and is configured so that maintenance, replacement, expansion, etc. of the integrated supply system 248 can be performed in units of integrated units.

[0020] The reaction tube 203 is provided with an exhaust pipe 231 for exhausting the atmosphere in the processing chamber 201. A vacuum pump 246 as a vacuum exhaust device is connected to the exhaust pipe 231 via a pressure sensor 245 as a pressure detector (pressure detection unit) for detecting the pressure in the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 as a pressure regulator (pressure adjustment unit). The APC valve 244 can evacuate and stop the evacuation of the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is in operation. Furthermore, the pressure in the processing chamber 201 can be adjusted by adjusting the valve opening based on pressure information detected by the pressure sensor 245 while the vacuum pump 246 is in operation. An exhaust system is mainly configured by the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may be included in the exhaust system.

[0021] Below the manifold 209, a seal cap 219 is provided as a furnace port cover body capable of airtightly closing the lower end opening of the manifold 209. The seal cap 219 is made of a metal such as SUS and is formed in a disk shape. An O-ring 220b is provided on the upper surface of the seal cap 219 as a seal member that abuts against the lower end of the manifold 209. Below the seal cap 219, a rotation mechanism 267 is provided for rotating the boat 217 described later. A rotation shaft 255 of the rotation mechanism 267 is connected to the boat 217 through the seal cap 219. The rotation mechanism 267 is configured to rotate the wafers 200 by rotating the boat 217. The seal cap 219 is configured to be raised and lowered in the vertical direction by a boat elevator 115 as a lifting mechanism installed outside the reaction tube 203. The boat elevator 115 is configured to be able to load and unload the boat 217 into and out of the processing chamber 201 by lifting and lowering the seal cap 219. The boat elevator 115 is configured as a transfer device (transfer mechanism) that transfers the boat 217, that is, the wafers 200, into and out of the processing chamber 201.

[0022] The boat 217 as a substrate support is configured to support a plurality of wafers 200, for example 25 to 200, in multiple stages in a horizontal position and aligned vertically with their centers aligned, i.e., arranged at intervals. The boat 217 is made of a heat-resistant material such as quartz or SiC. At the bottom of the boat 217, heat insulating plates 218 made of a heat-resistant material such as quartz or SiC are supported in multiple stages.

[0023] A temperature sensor 263 serving as a temperature detector is installed inside the reaction tube 203. By adjusting the power supply to the heater 207 based on temperature information detected by the temperature sensor 263, the temperature inside the processing chamber 201 can have a desired temperature distribution. The temperature sensor 263 is configured in an L-shape and is installed along the inner wall of the reaction tube 203.

[0024] 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.

[0025] The storage device 121c is composed of, for example, a flash memory, a hard disk drive (HDD), a solid state drive (SSD), etc. In the storage device 121c, a control program for controlling the operation of the substrate processing apparatus, a process recipe in which the procedure and conditions of a film formation process described later are described, etc. are recorded and stored in a readable manner. The process recipe is a combination of procedures in a film formation process described later that are executed by the controller 121 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. In addition, the process recipe is also simply referred to as a recipe. In this specification, when the word program is used, it may include only a recipe, only a control program, or both. The RAM 121b is configured as a memory area (work area) in which the programs and data read by the CPU 121a are temporarily stored.

[0026] The I / O port 121d is connected to the above-mentioned MFCs 241a to 241d, the valves 243a to 243d, the pressure sensor 245, the APC valve 244, the vacuum pump 246, the heater 207, the temperature sensor 263, the rotation mechanism 267, the boat elevator 115, and the like.

[0027] 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 an input of an operation command from the input / output device 122, etc. The CPU 121a is configured to be capable of controlling the flow rate adjustment operation of various gases by the MFCs 241a to 241d, the opening and closing operations of the valves 243a to 243d, the opening and closing operation of the APC valve 244 and the pressure adjustment operation by the APC valve 244 based on the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the rotation and rotation speed adjustment operation of the boat 217 by the rotation mechanism 267, the lifting and lowering operation of the boat 217 by the boat elevator 115, etc., in accordance with the contents of the read recipe.

[0028] The controller 121 can be configured by installing the above-mentioned program recorded and stored in an external storage device (for example, a magnetic disk such as a hard disk, an optical disk such as a CD, a magneto-optical disk such as an MO, or a semiconductor memory such as a USB memory) 123 into a computer. 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. 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. The program may be provided to the computer using a communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0029] (2) Substrate processing An example of a sequence for forming a film containing a predetermined element on a wafer 200 as one step of substrate processing in a manufacturing method of a semiconductor device (e.g., an IC) using the above-mentioned substrate processing apparatus will be described with reference to Fig. 4. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by a controller 121.

[0030] The term "wafer" 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 a wafer" 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 described in this specification, "forming a predetermined layer on a wafer" may mean forming a predetermined layer directly on the surface of the wafer itself or forming a predetermined layer on a layer or the like formed on the wafer. When used in this specification, the term "substrate" is synonymous with the term "wafer".

[0031] (Wafer loading step) 1, when a plurality of wafers 200 are loaded into the boat 217 (wafer charge), 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.

[0032] (Pressure and temperature adjustment step) The processing chamber 201, i.e., the space in which the wafer 200 is present, is evacuated (reduced pressure exhaust) by the vacuum pump 246 so that the pressure inside the processing chamber 201 is a desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback-controlled based on the measured pressure information. The vacuum pump 246 is kept in a constantly operating state at least until the processing of the wafer 200 is completed. In addition, the wafer 200 inside the processing chamber 201 is heated by the heater 207 so that the wafer 200 is at a desired temperature. At this time, the power supply to the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the processing chamber 201 has a desired temperature distribution. The heating inside the processing chamber 201 by the heater 207 continues at least until the processing of the wafer 200 is completed. In addition, the rotation mechanism 267 starts to rotate the boat 217 and the wafer 200. The rotation mechanism 267 continues to rotate the boat 217 and the wafers 200 at least until the processing of the wafers 200 is completed.

[0033] (First film formation process: high-speed film formation process) First, the following steps S11 to S14 are executed in sequence.

[0034] [Step S11] In this step, a source gas is supplied to the wafer 200 in the processing chamber 201 under a high-rate film formation condition, which is the first condition, and then exhausted. Specifically, the valve 243a is opened to allow the source gas to flow into the gas supply pipe 232a. The source gas is adjusted in flow rate by the MFC 241a, supplied into the processing chamber 201 through the nozzle 249a, and exhausted from the exhaust pipe 231. At the same time, the valve 243c is opened to allow an inert gas to flow into the gas supply pipe 232c. The inert gas is adjusted in flow rate by the MFC 241c, supplied into the processing chamber 201 together with the source gas, and exhausted from the exhaust pipe 231. In addition, in order to prevent the source gas from entering the nozzle 249b and / or to dilute the source gas supplied into the processing chamber 201, the valve 243d is opened to allow an inert gas to flow into the gas supply pipe 232d. The inert gas is supplied into the processing chamber 201 via the gas supply pipe 232 d and the nozzle 249 b , and is exhausted from the exhaust pipe 231 .

[0035] The inert gas supplied from the gas supply pipe 232c is mixed with the raw material gas in the gas supply pipe 232a to dilute the raw material gas, and then supplied to the wafer 200 from the gas supply hole 250a of the nozzle 249a. The inert gas supplied from the gas supply pipe 232d is supplied to the wafer 200 from the gas supply hole 250b of the nozzle 249b, which is a supply port different from the raw material gas supply port. The inert gas supplied from the gas supply pipes 232c and 232d dilutes the raw material gas, and can adjust the supply amount distribution of the raw material gas on the surface of the wafer 200.

[0036] In this step, the inert gas may be supplied from at least one of the gas supply pipes 232c and 232d. Also, during at least a part of the supply period of the source gas, the inert gas may be supplied to the wafer 200 from at least one of the gas supply pipes 232c and 232d.

[0037] The processing conditions for supplying the raw material gas in this step are as follows: Treatment temperature: 400 to 750°C, preferably 500 to 650°C Treatment pressure: 5 to 4000 Pa, preferably 10 to 1333 Pa Raw material gas supply flow rate: 1 to 2000 sccm, preferably 50 to 500 sccm Inert gas supply flow rate (total flow rate): 1 to 10,000 sccm, preferably 100 to 5,000 sccm Treatment time: 0.1 to 240 seconds, preferably 1 to 120 seconds Examples include:

[0038] In this specification, the process temperature means the temperature of the wafer 200 or the temperature in the process chamber 201, and the process pressure means the pressure in the process chamber 201. Furthermore, the process time means the time the process continues. These are the same in the following explanations. Furthermore, the expression of a numerical range such as "400 to 750°C" in this specification means that the lower limit and the upper limit are included in the range. Thus, for example, "400 to 750°C" means "400°C or more and 750°C or less." The same applies to other numerical ranges.

[0039] A source gas containing a predetermined element is supplied to the wafer 200 under high-rate film-forming conditions to form a first layer 400a containing the predetermined element on the wafer 200.

[0040] As the source gas, for example, a source gas containing silicon (Si) (Si-containing gas) can be used. As the source gas containing Si, for example, a chlorosilane-based gas such as dichlorosilane (SiH2Cl2) gas, trichlorosilane (SiHCl3), tetrachlorosilane (SiCl4), hexachlorodisilane (Si2Cl6), a fluorosilane-based gas such as tetrafluorosilane (SiF4) gas, an inorganic silane-based gas such as disilane (Si2H6), an aminosilane-based gas such as trisdimethylaminosilane (Si[N(CH3)2]3H), etc. can be used. As the source gas, one or more of these can be used.

[0041] As the inert gas, for example, nitrogen (N2) gas or rare gas such as argon (Ar), helium (He), neon (Ne), xenon (Xe), etc. As the inert gas, one or more of these can be used.

[0042] [Step S12] After step S11 is completed, the residual gas in the processing chamber 201 is removed.

[0043] Specifically, after the first layer 400a is formed in step S11, the valve 243a is closed to stop the supply of the source gas. At this time, the APC valve 244 is left open, and the inside of the processing chamber 201 is evacuated by the vacuum pump 246 to remove the source gas and by-products remaining in the processing chamber 201 that have not reacted or that have contributed to the formation of the first layer 400a from the inside of the processing chamber 201. At this time, the valves 243c and 243d are left open to maintain the supply of the inert gas into the processing chamber 201. The inert gas acts as a purge gas.

[0044] [Step S13] After step S12 is completed, reactive gas is supplied to the wafer 200 in the processing chamber 201. Specifically, the valve 243b is opened while the valve 243a is closed, and reactive gas is supplied into the gas supply pipe 232b. The valves 243c and 243d are controlled to open and close in the same manner as in step S11. The reactive gas is adjusted in flow rate by the MFC 241b, supplied into the processing chamber 201 through the nozzle 249b, and exhausted from the exhaust pipe 231. At this time, the reactive gas is supplied to the wafer 200. The inert gas is adjusted in flow rate by the MFC 241d, supplied into the processing chamber 201 together with the reactive gas, and exhausted from the exhaust pipe 231. In addition, in order to prevent the reactive gas from entering the nozzle 249a and / or to dilute the reactive gas supplied into the processing chamber 201, the valve 243c is opened, and the inert gas is supplied into the gas supply pipe 232c. The inert gas is supplied into the processing chamber 201 via the gas supply pipe 232 c and the nozzle 249 a , and is exhausted from the exhaust pipe 231 .

[0045] The process conditions for supplying the reaction gas in this step are as follows: Reactive gas supply flow rate: 100 to 30,000 sccm, preferably 500 to 10,000 sccm Inert gas supply flow rate (total flow rate): 1 to 10,000 sccm, preferably 100 to 5,000 sccm Treatment time: 1 to 240 seconds, preferably 1 to 120 seconds Examples are given below. The other conditions are preferably the same as those in step S11.

[0046] By supplying a reaction gas that reacts with the first layer 400a to the wafer 200 on which the first layer 400a is formed, the reaction gas reacts with at least a portion of the first layer 400a, modifying the first layer 400a into a second layer 400b containing a predetermined element.

[0047] As the reactive gas, for example, an N-containing gas containing nitrogen (N) can be used. In this step, the N-containing gas acts as a nitriding gas and reforms (nitrides) the first layer 400a into the second layer 400b as a nitrided layer containing a predetermined element. As the N-containing gas, for example, ammonia (NH3) gas, diazane (N2H2) gas, hydrazine (N2H4) gas, N3H8 gas, or other hydrogen nitride gas can be used. As the reactive gas, one or more of these can be used.

[0048] [Step S14] After step S13 is completed, the residual gas in the processing chamber 201 is removed. Specifically, after the second layer 400b is formed, the valve 243b is closed and the supply of the reactive gas is stopped. At this time, the APC valve 244 is left open, and the processing chamber 201 is evacuated by the vacuum pump 246 to remove the unreacted reactive gas and by-products remaining in the processing chamber 201 after contributing to the formation of the second layer 400b from the processing chamber 201. At this time, the valves 243c and 243d are left open to maintain the supply of the inert gas into the processing chamber 201. The inert gas acts as a purge gas.

[0049] [Perform the specified number of times] The above-described steps S11 to S14 constitute one cycle, and this cycle is performed a first predetermined number of times (n times, n is an integer equal to or greater than 1) to form a first film 400 containing a predetermined element on the wafer 200. As the first film 400, for example, a silicon nitride film (SiN film) can be formed.

[0050] (Second film formation process: low speed film formation process) Next, the following steps S21 to S24 are sequentially carried out at the same processing temperature as the above-mentioned steps S11 to S14.

[0051] Here, the term "same processing temperature" includes "substantially the same processing temperature." For example, fluctuations or fluctuations in the processing temperature that may occur when controlling the heater 207 to achieve the same processing temperature can be included in the range of "substantially the same processing temperature." In addition, the processing temperature in this specification refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201. This also applies to the following description.

[0052] [Step S21] In this step, the same source gas as that in the above-described step S11 is supplied to the wafer 200 in the processing chamber 201 under the low-rate film formation condition, which is the second condition, and then exhausted.

[0053] Specifically, similarly to those in step S11 described above, the valve 243a is opened to allow the raw material gas to flow into the gas supply pipe 232a. The raw material gas is adjusted in flow rate by the MFC 241a, supplied into the processing chamber 201 through the nozzle 249a, and exhausted from the exhaust pipe 231. At the same time, the valve 243c is opened to allow the inert gas to flow into the gas supply pipe 232c. The inert gas is adjusted in flow rate by the MFC 241c, supplied into the processing chamber 201 together with the raw material gas, and exhausted from the exhaust pipe 231. In addition, in order to prevent the intrusion of the reactive gas into the nozzle 249a and / or to dilute the raw material gas supplied into the processing chamber 201, the valve 243d is opened to allow the inert gas to flow into the gas supply pipe 232d. The inert gas is supplied into the processing chamber 201 through the gas supply pipe 232d and the nozzle 249b, and exhausted from the exhaust pipe 231.

[0054] The inert gas supplied from the gas supply pipe 232c is mixed with the raw material gas in the gas supply pipe 232a to dilute the raw material gas, and then supplied to the wafer 200 from the gas supply hole 250a of the nozzle 249a. The inert gas supplied from the gas supply pipe 232d is supplied to the wafer 200 from the gas supply hole 250b of the nozzle 249b, which is different from the raw material gas. The inert gas supplied from the gas supply pipes 232c and 232d dilutes the raw material gas, and can adjust the supply amount distribution of the raw material gas on the surface of the wafer 200.

[0055] The inert gas may be supplied from at least one of the gas supply pipes 232c and 232d. Also, the inert gas may be supplied to the wafers 200 from at least one of the gas supply pipes 232c and 232d during at least a part of the supply period of the source gas.

[0056] The processing conditions for supplying the raw material gas in this step are as follows: Raw material gas supply flow rate: 1 to 1000 sccm, preferably 25 to 250 sccm Inert gas supply flow rate (total flow rate): 1 to 20,000 sccm, preferably 200 to 10,000 sccm Treatment time: 0.1 to 120 seconds, preferably 1 to 60 seconds Examples are given below. The other conditions are preferably the same as those in step S11.

[0057] A source gas is supplied under low-rate film formation conditions to a wafer (200) having a first film (400) formed on its surface, to form a third layer (500a) on the first film (400) containing the same predetermined element as the first film.

[0058] Here, the low-rate film formation conditions are conditions under which the thickness of the third layer 500a formed in this step is thinner than the thickness of the first layer 400a formed in the above-mentioned step S11 under the high-rate film formation conditions. The low-rate film formation conditions are also conditions under which the thickness of the fourth layer 500b formed in step S23 described below is thinner than the thickness of the second layer 400b formed in the above-mentioned step S13 under the high-rate film formation conditions. In other words, the low-rate film formation conditions are conditions under which the cycle rate is smaller than that under the above-mentioned high-rate film formation conditions. The cycle rate refers to the thickness of the film (or layer) formed per cycle.

[0059] Specifically, the supply flow rate of the raw material gas in this step is set to be less than the supply flow rate of the raw material gas in the above-mentioned step S11. For example, the supply flow rate of the raw material gas in this step is set to be about 50% of the supply flow rate of the raw material gas in the above-mentioned step S11.

[0060] Also, the supply time of the raw material gas per cycle in this step may be shorter than the supply time of the raw material gas per cycle in the above-mentioned step S11. For example, the supply time of the raw material gas per cycle in this step is set to about half of the supply time of the raw material gas per cycle in the above-mentioned step S11.

[0061] Also, the supply concentration of the raw material gas in this step may be lower than the supply concentration of the raw material gas in the above-mentioned step S11. For example, the supply flow rate of the inert gas in this step is made higher than the supply flow rate of the inert gas in the above-mentioned step S11. As a result, the dilution amount of the raw material gas in this step is made larger than when the raw material gas is supplied in step S11, and the supply concentration of the raw material gas is made lower. For example, the supply flow rate of the inert gas in this step is made twice as high as the supply flow rate of the inert gas in the above-mentioned step S11. Also, the ratio of the supply flow rate of the inert gas to the supply flow rate of the raw material gas in this step is made higher than the ratio of the supply flow rate of the inert gas to the supply flow rate of the raw material gas in the above-mentioned step S11, and the supply concentration of the raw material gas is made lower. For example, the ratio of the supply flow rate of the inert gas to the supply flow rate of the raw material gas in this step is made about twice the ratio of the supply flow rate of the inert gas to the supply flow rate of the raw material gas in the above-mentioned step S11. In this case, it is preferable to make the total flow rate of the source gas and the inert gas supplied to the wafer 200 in step S11 the same as the total flow rate of the source gas and the inert gas supplied to the wafer 200 in step S21. By making the total flow rates the same, it is possible to adjust the amount of exposure of the source gas to the wafer 200 without changing conditions such as the pressure in the process chamber 201. Similarly, the partial pressure of the source gas in the space in which the wafer 200 exists in this step (for example, the partial pressure of the source gas in the process chamber 201) may be made lower than the partial pressure of the source gas in the above-mentioned step S11.

[0062] That is, by controlling at least one of the supply flow rate of the source gas, the supply time of the source gas, and the supply flow rate of the inert gas in the above-mentioned step S11 and this step, the exposure amount of the source gas is adjusted, and the thickness of the third layer 500a formed in this step can be made thinner than the thickness of the first layer 400a formed in the above-mentioned step S11. That is, the cycle rate in this step can be made smaller than the cycle rate in the above-mentioned step S11.

[0063] In addition, by adjusting the supply amount, supply time, or supply concentration (partial pressure) of the source gas at a processing temperature substantially the same as that in step S11 described above, it is possible to control the cycle rate without causing any change in the film quality or to minimize the change in the film quality.

[0064] That is, the low-rate film-forming conditions in this step and the high-rate film-forming conditions in S11 described above are set so as to adjust the thickness of the layer containing the predetermined element formed by the supply of the source gas.

[0065] [Step S22] After step S21 is completed, the residual gas in the processing chamber 201 is removed. Specifically, after the third layer 500a is formed, the valve 243a is closed and the supply of the source gas is stopped. At this time, the APC valve 244 is left open, and the processing chamber 201 is evacuated by the vacuum pump 246 to remove the source gas and by-products remaining in the processing chamber 201 that have not reacted or that have contributed to the formation of the third layer 500a from the processing chamber 201. At this time, the valves 243c and 243d are left open to maintain the supply of the inert gas into the processing chamber 201. The inert gas acts as a purge gas.

[0066] [Step S23] After step S22 is completed, the same gas as in step S13 described above is flowed to the wafer 200 in the processing chamber 201 under the same conditions and procedures as in step S13. Specifically, the valve 243b is opened while the valve 243a is closed, and the reactive gas is flowed into the gas supply pipe 232b. The opening and closing control of the valves 243c and 243d is controlled in the same manner as in step S13. The reactive gas is adjusted in flow rate by the MFC 241b, supplied into the processing chamber 201 through the nozzle 249b, and exhausted from the exhaust pipe 231. At this time, the reactive gas is supplied to the wafer 200. The inert gas is adjusted in flow rate by the MFC 241d, supplied into the processing chamber 201 together with the reactive gas, and exhausted from the exhaust pipe 231.

[0067] By supplying a reactive gas to the wafer 200 on which the third layer 500a is formed, at least a part of the third layer 500a is modified into a fourth layer 500b containing a predetermined element. For example, by using an N-containing gas as the reactive gas, the first layer 400a is modified (nitrided) into the fourth layer 500b as a nitride layer containing the predetermined element.

[0068] [Step S24] After step S23 is completed, the residual gas in the processing chamber 201 is removed. Specifically, after the fourth layer 500b is formed, the valve 243b is closed and the supply of the reactive gas is stopped. At this time, the APC valve 244 is left open, and the processing chamber 201 is evacuated by the vacuum pump 246 to remove the unreacted reactive gas and by-products remaining in the processing chamber 201 after contributing to the formation of the fourth layer 500b from the processing chamber 201. At this time, the valves 243c and 243d are left open to maintain the supply of the inert gas into the processing chamber 201. The inert gas acts as a purge gas.

[0069] [Perform the specified number of times] The above-mentioned steps S21 to S24 constitute one cycle, and this cycle is performed a second predetermined number of times (m times, where m is an integer equal to or greater than 1) to form a second film 500 containing a predetermined element on the first film 400 of the wafer 200.

[0070] That is, the above-mentioned steps S11 to S14 are regarded as one cycle, and a process of performing this cycle a first predetermined number of times, and the above-mentioned steps S21 to S24 are regarded as one cycle, and a process of performing this cycle a second predetermined number of times are performed, thereby forming a film including a predetermined element composed of a first film 400 and a second film 500. The first film 400 and the second film 500 include the same predetermined element and have the same composition. When, for example, a SiN film is formed as the first film 400, the film composed of the first film 400 and the second film 500 is a SiN film. Here, "same" includes "substantially the same." By stacking the first film 400 and the second film 500 having substantially the same composition, it is possible to control only the film thickness without substantially changing the composition.

[0071] Furthermore, by performing the above-mentioned step S21 at a processing temperature substantially the same as the processing temperature in the above-mentioned step S11, a change in the film properties of the first film 400 and the second film 500 can be suppressed.

[0072] (After purge and atmospheric pressure return step) An inert gas is supplied into the processing chamber 201 from each of the gas supply pipes 232c and 232d, and exhausted from the exhaust pipe 231. The inert gas acts as a purge gas. This purges the processing chamber 201, and gas and reaction by-products remaining in the processing chamber 201 are removed from the processing chamber 201 (after-purge). Thereafter, the atmosphere in the processing chamber 201 is replaced with the inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure (return to atmospheric pressure).

[0073] (Boat unloading and wafer discharging) The seal cap 219 is lowered by the boat elevator 115, and the lower end of the manifold 209 is opened. Then, the processed wafers 200 supported by the boat 217 are unloaded from the lower end of the manifold 209 to the outside of the reaction tube 203 (boat unloading). The processed wafers 200 are removed from the boat 217 (wafer discharging).

[0074] For example, in the case of forming a SiN film using a Si-containing gas as a source gas and a N-containing gas as a reactive gas, the above-mentioned film formation sequence can be expressed as follows.

[0075] (Si-containing gas → N-containing gas) × n → (Si-containing gas → N-containing gas) × m → SiN

[0076] FIG. 5(B) is a diagram showing a case where a film 400 is formed on a wafer 200 by performing a cycle of steps S11 to S14 only under the above-mentioned high-rate film formation conditions a predetermined number of times. When a film is formed only under the high-rate film formation conditions, the cycle rate is high and the thickness of the layer 400b formed per cycle is large, so that a film can be formed to the target film thickness T in a small number of cycles. This reduces the film formation time and improves throughput. On the other hand, the film thickness of a film formed only under the high-rate film formation conditions can only be p times the layer thickness of the layer 400b (p is an integer of 1 or more). Therefore, when the target film thickness T is different from p times the layer thickness of the layer 400b, the film cannot be made closer to the target film thickness T.

[0077] 5(C) is a diagram showing a case where a film 500 is formed on a wafer 200 by performing a cycle of steps S21 to S24 only under the above-mentioned low-rate film-forming conditions a predetermined number of times. When film-forming is performed only under the low-rate film-forming conditions, the cycle rate is smaller than under the high-rate film-forming conditions, and the thickness of the layer 500b formed per cycle is smaller, so that a film must be formed to the target film thickness T in a greater number of cycles than under the high-rate film-forming conditions. In other words, the film-forming time increases compared to under the high-rate film-forming conditions, and the throughput decreases. On the other hand, the error from the target film thickness T can be made smaller compared to under the high-rate film-forming conditions.

[0078] In this embodiment, as shown in FIG. 5(C), a cycle of steps S11 to S14 is performed a first predetermined number of times under high-rate film-forming conditions to form a first film 400, and a cycle of steps S21 to S24 is performed a second predetermined number of times under low-rate film-forming conditions to form a second film 500. That is, the first predetermined number and the second predetermined number are adjusted. In other words, two processes with different cycle rates are performed. This makes it possible to form a film containing a predetermined element on the wafer 200 with a small error from the target film thickness T. Also, compared to a case where a film is formed under only low-rate film-forming conditions, the film-forming time can be shortened, and throughput can be improved.

[0079] That is, two processes with different cycle rates are performed to form a film containing a predetermined element. Specifically, for example, a first film 400 is formed under high-speed film formation conditions with a high cycle rate up to about 95% of the target film thickness T, which is the desired film thickness, and a second film 500 is formed under low-speed film formation conditions with a low cycle rate for the remaining 5% to fine-tune the film thickness. In this way, a film containing a predetermined element and having a target film thickness T, which is composed of the first film 400 and the second film 500, is formed on the wafer 200. Therefore, even when high accuracy is required for the desired film thickness, it is possible to form a film with high accuracy while improving throughput.

[0080] Here, the first predetermined number of times and the second predetermined number of times are set (selected) so as to reduce the error between the total film thickness of the first film 400 and the second film 500 and the target film thickness T, and it is particularly desirable to set them so as to minimize this error.

[0081] For example, the thickness of the second film 500 formed by performing the cycle of steps S21 to S24 a second predetermined number of times is set to be thinner than the thickness of the first film 400 formed by performing the cycle of steps S11 to S14 a first predetermined number of times. That is, the first predetermined number of times is set to be greater than the second predetermined number of times, for example, 2 or more. The throughput can be improved by forming a film with a target thickness T by increasing the thickness of the first film 400 formed under high-speed film-forming conditions with a high cycle rate and adjusting the thickness of the second film 500 formed under low-speed film-forming conditions with a low cycle rate. In addition, the throughput can be improved by making the number of film-forming cycles under high-speed film-forming conditions with a high cycle rate greater than the number of film-forming cycles under low-speed film-forming conditions with a low cycle rate.

[0082] Specifically, the first and second predetermined times are set so that the difference between the target film thickness T and the total film thickness of the first film 400 and the second film 500 is smaller than the minimum possible difference between N times (N is any natural number) the thickness of the second layer 400b formed in step S13 and the target film thickness T. This makes it possible to reduce the error with respect to the target film thickness T.

[0083] The first and second predetermined times can be set so that the thickness of the second film 500 formed under the low-rate deposition conditions is thinner than the thickness of the second layer 400b formed per cycle under the high-rate deposition conditions. This can reduce the error with respect to the target film thickness T and can minimize the second predetermined number of times to improve throughput.

[0084] Alternatively, the cycle of steps S11 to S14 may be performed a predetermined number of times under high-rate film formation conditions, and when the film thickness up to the target film thickness T becomes smaller than the film thickness of the second layer 400b formed per cycle, low-rate film formation processing may be performed. In this case, the number of times that the cycle of steps S11 to S14 is performed under high-rate film formation conditions is set to the maximum number at which n times (n is any natural number) the thickness of the second layer 400b formed per cycle under high-rate film formation conditions is equal to or smaller than the target film thickness T. After the first film 400 is formed, the film thickness of the second film 500 formed by the low-rate film formation processing is finely adjusted to form a film having a thickness that minimizes the error from the target film thickness T.

[0085] In the above example, a case has been described in which the cycle of steps S11 to S14 is performed a first predetermined number of times under high-rate film formation conditions, and then the cycle of steps S21 to S24 is performed a second predetermined number of times under low-rate film formation conditions, thereby forming the second film 500 on the first film 400. The present disclosure is not limited to such a case, and the first film 400 may be formed on the second film 500 by performing the cycle of steps S21 to S24 a second predetermined number of times under low-rate film formation conditions, and then performing the cycle of steps S11 to S14 a first predetermined number of times under high-rate film formation conditions.

[0086] In addition, the cycle of steps S11 to S14 may be performed a predetermined number of times under high-rate film formation conditions, and when the error between the formed first film 400 and the target film thickness T becomes small, the film thickness of the first film 400 may be measured, and based on the measurement results, a second predetermined number of times may be calculated that minimizes the error from the target film thickness T, and then the low-rate film formation process may be performed.

[0087] <Other Aspects of the Disclosure> (Second aspect) Next, a second embodiment of the above-mentioned substrate processing apparatus will be described with reference to Fig. 6. In the substrate processing apparatus in the second embodiment, elements that are substantially the same as those described in Fig. 1 are denoted by the same reference numerals, and description thereof will be omitted.

[0088] 6, in the second embodiment, a valve 302, a tank 300 serving as a storage unit for storing gas, and a valve 304 are provided in this order from the upstream side of the gas flow downstream of the valve 243a of the gas supply pipe 232a serving as the source gas supply system and downstream of the junction with the gas supply pipe 232c serving as the inert gas supply system. That is, the tank 300 and the valves 302 and 304 are provided on the supply lines for the source gas and the inert gas.

[0089] The tank 300 temporarily stores the source gas supplied from the gas supply pipe 232a and the inert gas supplied from the gas supply pipe 232c in the tank 300 by opening and closing the upstream valve 302 and the downstream valve 304. In the tank 300, the source gas and the inert gas are mixed, and the source gas is diluted with the inert gas. Then, the source gas stored in the tank 300 and diluted with the inert gas is supplied to the wafers 200 in large quantities at one time.

[0090] In the second embodiment, in the supply of source gases in steps S11 and S21 of the substrate processing step of the above embodiment, flush supply is performed using the tank 300 and valves 302 and 304 at substantially the same processing temperature.

[0091] Specifically, in the supply of source gas in steps S11 and S21, valve 304 is closed in advance, and valves 243a, 243c, and 302 are opened, so that the source gas and inert gas whose flow rates are adjusted by MFCs 241a and 241c, respectively, are stored in tank 300. Then, valve 304 is opened to supply a large amount of the mixed gas of source gas and inert gas stored in tank 300 to wafers 200 at once. That is, a large amount of diluted source gas is supplied to wafers 200 at once.

[0092] At this time, in steps S11 and S21, the MFCs 241a, 241c and the valves 243a, 243c are controlled, respectively, to control the supply flow rate of the raw material gas and the supply flow rate of the inert gas, thereby adjusting the supply concentration of the raw material gas in the tank 300 (i.e., the partial pressure of the raw material gas in the tank 300). That is, the flow rate ratio of the raw material gas to the inert gas in the above-mentioned step S11 and the flow rate ratio of the raw material gas to the inert gas in the above-mentioned step S21 are adjusted.

[0093] For example, the supply concentration of the raw material gas is adjusted so that the flow rate ratio of the raw material gas to the inert gas in step S21 is smaller than the flow rate ratio of the raw material gas to the inert gas in step S11, and the raw material gas is stored in the tank 300. In other words, the ratio of the supply flow rate of the inert gas to the supply flow rate of the raw material gas in step S21 is made larger than the ratio of the supply flow rate of the inert gas to the supply flow rate of the raw material gas in step S11 described above. This allows the thickness of the third layer 500a formed in step S21 to be thinner than the thickness of the first layer 400a formed in step S11. That is, the cycle rate in step S21 can be made smaller than the cycle rate in step S11. In this case, the total flow rate of the raw material gas and the inert gas stored in the tank in advance in step S11 is made the same as the total flow rate of the raw material gas and the inert gas stored in the tank in advance in step S21. By making the total flow rates the same, the exposure amount of the raw material gas to the wafer 200 can be adjusted without changing conditions such as the pressure in the processing chamber 201.

[0094] In this embodiment, the same effects as those in the above embodiment can be obtained. In addition, in this embodiment, the wafer 200 is exposed to a large amount of source gas in a short period of time, thereby improving step coverage.

[0095] One embodiment of the present disclosure has been specifically described above. However, the present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the spirit and scope of the present disclosure.

[0096] For example, in the above embodiment, the case where a N-containing gas is used as the reactive gas has been described as an example, but the present invention is not limited thereto, and for example, an O-containing gas containing oxygen (O) can be used. As the O-containing gas, for example, O2 gas, O3 gas, nitrous oxide (NO) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, carbon monoxide (CO) gas, carbon dioxide (CO2) gas, etc. can be used. One or more of these can be used.

[0097] Furthermore, when a Si-containing gas is used as the source gas and an O-containing gas is used as the reactive gas, a silicon oxide film (SiO film) is formed, and the same effects as those of the above embodiment can be obtained when a SiO film is formed on a substrate.

[0098] In addition, the same effects as those of the above embodiment can be obtained when a plasma-excited reactive gas is used as the reactive gas. For example, a N-containing gas may be plasma-excited as the plasma-excited reactive gas.

[0099] In the above embodiment, the case where the raw material gas supply and the reactive gas supply are performed has been described as an example, but the present invention is not limited thereto, and can also be applied to a case where, in addition to the raw material gas supply and the reactive gas supply, a modifying gas supply for modifying the film quality is performed to form a film containing a predetermined element on the wafer 200. Specifically, the same effect as the above embodiment can be obtained when a SiN film is formed on a substrate by a film formation sequence that uses, for example, a Si-containing gas as the raw material gas, a N-containing gas as the reactive gas, and a hydrogen (H)-containing gas such as H2 gas as the modifying gas, and performs the following cycle n times under high-speed film formation conditions when the raw material gas is supplied, and performs the following cycle m times under low-speed film formation conditions when the raw material gas is supplied.

[0100] (Si-containing gas → H-containing gas → N-containing gas) × n → (Si-containing gas → H-containing gas → N-containing gas) × m → SiN

[0101] In addition, when a SiO film is formed on a substrate by a film formation sequence that includes a step of performing the following cycle n times under high-rate film formation conditions when the raw material gas is supplied, using, for example, a Si-containing gas as a raw material gas, an O-containing gas as a reactive gas, and, for example, a H-containing gas as a modifying gas, and a step of performing the following cycle m times under low-rate film formation conditions when the raw material gas is supplied, the same effect as the above-mentioned embodiment can be obtained.

[0102] (Si-containing gas → H-containing gas → O-containing gas) × n → (Si-containing gas → H-containing gas → O-containing gas) × m → SiO (Si-containing gas → H-containing gas + O-containing gas) × n → (Si-containing gas → H-containing gas + O-containing gas) × m → SiO

[0103] In the above-mentioned embodiment, the case where a film containing Si is formed as a film containing a predetermined element is described as an example, but the present disclosure is not limited thereto. The film containing a predetermined element may be a film containing a metal element such as, for example, titanium nitride film (TiN film), tungsten film (W film), tungsten nitride film (WN film), hafnium nitride film (HfN film), zirconium nitride film (ZrN film), tantalum nitride film (TaN film), molybdenum film (Mo film), molybdenum nitride film (MoN film), aluminum film (Al film), aluminum nitride film (AlN film), ruthenium film (Ru film), cobalt film (Co film), titanium film (Ti film), etc. In these cases, the same effect as the above-mentioned embodiment can be obtained.

[0104] In the above-mentioned embodiment, an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at a time has been described. The present disclosure is not limited to the above-mentioned embodiment, and can be suitably applied to, for example, a case where a film is formed using a single-wafer type substrate processing apparatus that processes one or several substrates at a time. In addition, in the above-mentioned embodiment, an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace has been described. The present disclosure is not limited to the above-mentioned embodiment, and can be suitably applied to, for example, a case where a film is formed using a substrate processing apparatus having a cold-wall type processing furnace.

[0105] When these substrate processing apparatuses are used, the processes can be performed under the same processing procedures and conditions as in the above embodiment, and the same effects as in the above embodiment can be obtained.

[0106] The above-mentioned aspects may be used in appropriate combination. The processing procedures and processing conditions in this case may be the same as those of the above-mentioned aspects. EXAMPLES

[0107] The above-mentioned substrate processing apparatus was used to perform the above-mentioned substrate processing process to form a SiN film on a wafer. The above-mentioned chlorosilane-based gas was used as the source gas, the above-mentioned hydrogen nitride-based gas was used as the reactive gas, and N2 gas was used as the inert gas. The target film thickness T was set to 100 Å.

[0108] The cycle rate was 1.018 Å / cycle when the wafer was subjected to high-speed deposition processing with 100% source gas. In contrast, the cycle rate was 0.76 Å / cycle when the wafer was subjected to low-speed deposition processing with 50% source gas and 50% inert gas. First, 96 cycles of steps S11 to S14 were performed under high-speed deposition conditions to form a SiN film with a thickness of 97.7 Å, which is about 95% of the target thickness T. Next, 3 cycles of steps S21 to S24 were performed under low-speed deposition conditions to form a SiN film with a thickness of 2.3 Å. In other words, the total thickness was 100 Å, and it was confirmed that a film thickness that was not different from the target thickness T was formed by performing processing under high-speed deposition conditions and processing under low-speed deposition conditions. [Explanation of symbols]

[0109] 200 Wafer (substrate)

Claims

1. (a) (a-1) supplying a source gas containing a predetermined element to a substrate to form a first layer containing the predetermined element on the substrate; (a-2) supplying a reaction gas that reacts with the first layer to the substrate on which the first layer is formed, thereby modifying the first layer into a second layer containing the predetermined element; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) supplying the source gas to the substrate to form a third layer containing the predetermined element on the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a second predetermined number of times under second conditions different from the first conditions to form a second film containing the predetermined element on the substrate; a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of (a) and (b) are performed at the same treatment temperature, and the first condition and the second condition are conditions under which the thickness of the fourth layer formed in (b-2) is thinner than the thickness of the second layer formed in (a-2). A method for processing a substrate.

2. The method of claim 1 , wherein the first film and the second film have the same composition.

3. the first condition is a condition for supplying the source gas to the substrate in (a-1), the second condition is a condition for supplying the source gas to the substrate in (b-1), 2. The substrate processing method according to claim 1, wherein the second condition is a condition under which a thickness of the third layer is thinner than a thickness of the first layer. (a)(a-1) forming a first layer containing a predetermined element on a substrate by supplying a source gas containing the predetermined element to the substrate; (a-2) supplying a reaction gas that reacts with the first layer to the substrate on which the first layer is formed, thereby modifying the first layer into a second layer containing the predetermined element; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) supplying the source gas to the substrate to form a third layer containing the predetermined element on the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a second predetermined number of times under second conditions different from the first conditions to form a second film containing the predetermined element on the substrate; a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2); the supply flow rate of the raw material gas in the second condition (b-1) is lower than the supply flow rate of the raw material gas in the first condition (a-1); A method for processing a substrate. (a)(a-1) forming a first layer containing a predetermined element on a substrate by supplying a source gas containing the predetermined element to the substrate; (a-2) supplying a reaction gas that reacts with the first layer to the substrate on which the first layer is formed, thereby modifying the first layer into a second layer containing the predetermined element; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) supplying the source gas to the substrate to form a third layer containing the predetermined element on the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a second predetermined number of times under second conditions different from the first conditions to form a second film containing the predetermined element on the substrate; a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2); a supply time of the source gas per cycle under the second condition (b-1) is shorter than a supply time of the source gas per cycle under the first condition (a-1); A method for processing a substrate. (a)(a-1) forming a first layer containing a predetermined element on a substrate by supplying a source gas containing the predetermined element to the substrate; (a-2) supplying a reaction gas that reacts with the first layer to the substrate on which the first layer is formed, thereby modifying the first layer into a second layer containing the predetermined element; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) supplying the source gas to the substrate to form a third layer containing the predetermined element on the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a second predetermined number of times under second conditions different from the first conditions to form a second film containing the predetermined element on the substrate; a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2); the supply concentration of the source gas under the second condition (b-1) is lower than the supply concentration of the source gas under the first condition (a-1); A method for processing a substrate. (a)(a-1) forming a first layer containing a predetermined element on a substrate by supplying a source gas containing the predetermined element to the substrate; (a-2) supplying a reaction gas that reacts with the first layer to the substrate on which the first layer is formed, thereby modifying the first layer into a second layer containing the predetermined element; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) supplying the source gas to the substrate to form a third layer containing the predetermined element on the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a second predetermined number of times under second conditions different from the first conditions to form a second film containing the predetermined element on the substrate; a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2); In (a-1) and (b-1), an inert gas is supplied to the substrate during at least a part of a supply period of the source gas, and a supply flow rate of the inert gas in (b-1) as the second condition is higher than a supply flow rate of the inert gas in (a-1) as the first condition. A method for processing a substrate. (a)(a-1) forming a first layer containing a predetermined element on a substrate by supplying a source gas containing the predetermined element to the substrate; (a-2) supplying a reaction gas that reacts with the first layer to the substrate on which the first layer is formed, thereby modifying the first layer into a second layer containing the predetermined element; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) supplying the source gas to the substrate to form a third layer containing the predetermined element on the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a second predetermined number of times under second conditions different from the first conditions to form a second film containing the predetermined element on the substrate; a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2); In (a-1) and (b-1), an inert gas is supplied to the substrate during at least a part of a supply period of the source gas, and a ratio of a supply flow rate of the inert gas to a supply flow rate of the source gas in (b-1) as the second condition is greater than a ratio of a supply flow rate of the inert gas to a supply flow rate of the source gas in (a-1) as the first condition. A method for processing a substrate.

9. 9. The substrate processing method according to claim 7, wherein the inert gas is supplied to the substrate from a supply port different from that of the source gas.

10. 9. The substrate processing method according to claim 7, wherein the inert gas is mixed with the source gas and then supplied to the substrate.

11. 9. The substrate processing method according to claim 7 or 8, wherein a tank and a valve are provided on a supply line for the source gas and the inert gas, and in (a-1) and (b-1), the valve is closed to store the source gas and the inert gas in the tank, and the valve is opened to supply the stored source gas and the inert gas to the substrate.

12. 12. The substrate processing method according to claim 11, wherein a flow rate ratio of the source gas to the inert gas in (b-1) is made smaller than a flow rate ratio of the source gas to the inert gas in (a-1), thereby making a thickness of the third layer formed in (b-1) thinner than a thickness of the first layer formed in (a-1).

13. 2. The substrate processing method according to claim 1, wherein the second film formed in (b) has a thickness smaller than a thickness of the first film formed in (a).

14. The substrate processing method according to claim 1 , wherein the first predetermined number of times is greater than the second predetermined number of times.

15. 2. The substrate processing method of claim 1, wherein (b) is performed after (a), and the second film is formed on the first film.

16. 2. The substrate processing method according to claim 1, wherein the first predetermined number of times and the second predetermined number of times are set so that a difference between a target film thickness and a thickness of a film containing the specified element, which is composed of the first film and the second film, is smaller than a minimum possible difference between n times (n is any natural number) a thickness of the second layer formed per cycle in (a-2) and the target film thickness.

17. A method for manufacturing a semiconductor device, comprising a step of carrying out a substrate processing method according to any one of claims 1 and 4 to 8.

18. A program for causing a substrate processing apparatus to execute a procedure for performing the substrate processing method described in any one of claims 1, 4 to 8 by a computer.

19. A source gas supply system for supplying a source gas containing a predetermined element to a substrate; a reactive gas supply system for supplying a reactive gas to the substrate; an exhaust system that exhausts a space in which the substrate is present; (a) (a-1) a process of forming a first layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (a-2) a process of modifying the first layer into a second layer containing the predetermined element by supplying the reaction gas to the substrate on which the first layer is formed; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) a process of forming a third layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (b-2) supplying the reactive gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a process of forming a second film containing the predetermined element on the substrate by performing a cycle including the steps of: a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of a control unit configured to be capable of controlling the source gas supply system, the reactive gas supply system, and the exhaust system so as to perform processes (a) and (b) under the same processing temperature, and the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2); The substrate processing apparatus includes:

20. A source gas supply system for supplying a source gas containing a predetermined element to a substrate; a reactive gas supply system for supplying a reactive gas to the substrate; an exhaust system that exhausts a space in which the substrate is present; (a) (a-1) a process of forming a first layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (a-2) a process of modifying the first layer into a second layer containing the predetermined element by supplying the reaction gas to the substrate on which the first layer is formed; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) a process of forming a third layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a process of forming a second film containing the predetermined element on the substrate by performing a cycle including the steps of: a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of a control unit configured to be capable of controlling the source gas supply system, the reactive gas supply system, and the exhaust system so that the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2), and a supply flow rate of the source gas in (b-1) as the second condition is lower than a supply flow rate of the source gas in (a-1) as the first condition; The substrate processing apparatus includes:

21. A source gas supply system for supplying a source gas containing a predetermined element to a substrate; a reactive gas supply system for supplying a reactive gas to the substrate; an exhaust system that exhausts a space in which the substrate is present; (a) (a-1) a process of forming a first layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (a-2) a process of modifying the first layer into a second layer containing the predetermined element by supplying the reaction gas to the substrate on which the first layer is formed; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) a process of forming a third layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a process of forming a second film containing the predetermined element on the substrate by performing a cycle including the steps of: a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of a control unit configured to be capable of controlling the source gas supply system, the reactive gas supply system, and the exhaust system so that the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2), and a supply time of the source gas per cycle in (b-1) as the second condition is shorter than a supply time of the source gas per cycle in (a-1) as the first condition; The substrate processing apparatus includes:

22. A source gas supply system for supplying a source gas containing a predetermined element to a substrate; a reactive gas supply system for supplying a reactive gas to the substrate; an exhaust system that exhausts a space in which the substrate is present; (a) (a-1) a process of forming a first layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (a-2) a process of modifying the first layer into a second layer containing the predetermined element by supplying the reaction gas to the substrate on which the first layer is formed; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) a process of forming a third layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (b-2) supplying the reactive gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a process of forming a second film containing the predetermined element on the substrate by performing a cycle including the steps of: a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of a control unit configured to be capable of controlling the source gas supply system, the reactive gas supply system, and the exhaust system so as to perform processing in which the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2), and the supply concentration of the source gas in (b-1) as the second condition is thinner than a supply concentration of the source gas in (a-1) as the first condition; The substrate processing apparatus includes:

23. A source gas supply system for supplying a source gas containing a predetermined element to a substrate; a reactive gas supply system for supplying a reactive gas to the substrate; an inert gas supply system for supplying an inert gas to the substrate; an exhaust system that exhausts a space in which the substrate is present; (a) (a-1) a process of forming a first layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (a-2) a process of modifying the first layer into a second layer containing the predetermined element by supplying the reaction gas to the substrate on which the first layer is formed; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) a process of forming a third layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (b-2) supplying the reaction gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a process of forming a second film containing the predetermined element on the substrate by performing a cycle including the steps of: a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of a control unit configured to be capable of controlling the source gas supply system, the reaction gas supply system, the inert gas supply system, and the exhaust system so that the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2), and the inert gas is supplied to the substrate during at least a part of a supply period of the source gas in each of (a-1) and (b-1), and a supply flow rate of the inert gas in (b-1) as the second condition is higher than a supply flow rate of the inert gas in (a-1) as the first condition; The substrate processing apparatus includes:

24. A source gas supply system for supplying a source gas containing a predetermined element to a substrate; a reactive gas supply system for supplying a reactive gas to the substrate; an inert gas supply system for supplying an inert gas to the substrate; an exhaust system that exhausts a space in which the substrate is present; (a) (a-1) a process of forming a first layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (a-2) a process of modifying the first layer into a second layer containing the predetermined element by supplying the reaction gas to the substrate on which the first layer is formed; a first predetermined number of times under first conditions to form a first film containing the predetermined element on the substrate; (b) (b-1) a process of forming a third layer containing the predetermined element on the substrate by supplying the source gas to the substrate; (b-2) supplying the reactive gas to the substrate on which the third layer is formed, thereby modifying the third layer into a fourth layer containing the predetermined element; a process of forming a second film containing the predetermined element on the substrate by performing a cycle including the steps of: a film including the predetermined element and including the first film and the second film is formed by carrying out the steps of a control unit configured to be capable of controlling the source gas supply system, the reaction gas supply system, the inert gas supply system, and the exhaust system so as to perform processing in which the first condition and the second condition are conditions under which a thickness of the fourth layer formed in (b-2) is thinner than a thickness of the second layer formed in (a-2), and in which the inert gas is supplied to the substrate during at least a part of a supply period of the source gas in each of (a-1) and (b-1), and a ratio of a supply flow rate of the inert gas to a supply flow rate of the source gas in (b-1) as the second condition is greater than a ratio of a supply flow rate of the inert gas to a supply flow rate of the source gas in (a-1) as the first condition; The substrate processing apparatus includes:

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