Substrate processing method

Abstract

To provide a technology capable of uniformly processing a substrate.SOLUTION: A silicon nitride film is formed on a substrate by performing predetermined times the steps of: supplying dichloro silane gas using as raw material gas to the substrate; supplying ammonia gas using as reaction gas to the substrate; and supplying hydrogen gas using as modified gas to the substrate.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a substrate processing method. [Background technology]

[0002] One of the processes for manufacturing semiconductor devices involves substrate processing, in which a substrate is carried into a processing chamber of a substrate processing apparatus, and raw material gases and reactive gases supplied into the processing chamber are activated using plasma to form or remove various films, such as insulating films, semiconductor films, and conductor films, on the substrate. Plasma is used to promote reactions in thin films to be deposited, remove impurities from thin films, or assist chemical reactions of film-forming raw materials (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-92637 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the gradual miniaturization of semiconductor device manufacturing, there is a demand for substrate processing at lower temperatures. To address this, solutions such as increasing the high-frequency power of the plasma source have been considered to uniformly process the specified film. However, increasing the high-frequency power can sometimes make it difficult to uniformly process the specified film.

[0005] An object of the present invention is to provide a technique that enables uniform processing of a substrate. [Means for solving the problem]

[0006] According to one aspect of the present invention, supplying dichlorosilane gas as a source gas to the substrate; supplying ammonia gas as a reactive gas to the substrate; supplying hydrogen gas as a modifying gas to the substrate; By repeating the above steps a predetermined number of times, a silicon nitride film is formed on the substrate. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a technique that enables uniform processing of a substrate. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferably used in an embodiment of the present invention, showing a processing furnace portion in vertical cross section. [Figure 2] 2 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferably used in an embodiment of the present invention, showing a processing furnace portion in a cross section taken along line AA in FIG. 1. FIG. [Figure 3] 1A is an enlarged cross-sectional view illustrating a buffer structure of a substrate processing apparatus preferably used in an embodiment of the present invention, and FIG. 1B is a schematic view illustrating a buffer structure of a substrate processing apparatus preferably used in an embodiment of the present invention. [Figure 4] FIG. 1 is a schematic configuration diagram of a controller of a substrate processing apparatus preferably used in an embodiment of the present invention, showing a control system of the controller in a block diagram. [Figure 5] 1 is a flowchart of a substrate processing process according to an embodiment of the present invention. [Figure 6] 5A and 5B are diagrams illustrating gas supply timings in a substrate processing step according to an embodiment of the present invention. [Figure 7] FIG. 10 is a schematic cross-sectional view illustrating a first modified example of a vertical processing furnace of a substrate processing apparatus that is preferably used in an embodiment of the present invention. [Figure 8] FIG. 10 is a schematic cross-sectional view illustrating a second modified example of a vertical processing furnace of a substrate processing apparatus that is preferably used in an embodiment of the present invention. [Figure 9]FIG. 10 is a schematic cross-sectional view illustrating a third modified example of a vertical processing furnace of a substrate processing apparatus that is preferably used in an embodiment of the present invention. [Figure 10] FIG. 10 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferably used in another embodiment of the present invention, showing a processing furnace portion in vertical cross section. [Figure 11] FIG. 10 is a diagram showing gas supply timing in a substrate processing step according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] <Embodiments of the present invention> Hereinafter, one embodiment of the present invention will be described with reference to FIGS.

[0010] (1) Configuration of the substrate processing equipment (heating device) 1, the processing furnace 202 is a so-called vertical furnace capable of accommodating substrates in multiple vertical stages, and includes a heater 207 as a heating device (heating mechanism). The heater 207 is cylindrical and is installed vertically by being supported by a heater base (not shown) as a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) gases with heat, as described below.

[0011] (Processing chamber) A reaction tube 203 is disposed concentrically inside the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2), silicon carbide (SiC), or silicon nitride (SiN), and is cylindrically shaped with a closed upper end and an open lower end. A manifold (inlet flange) 209 is disposed concentrically below the reaction tube 203. The manifold 209 is made of a metal such as stainless steel (SUS), and is cylindrically shaped with open upper and lower ends. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 to support the reaction tube 203. An O-ring 220a is disposed between the manifold 209 and the reaction tube 203 as a sealing member. The manifold 209 is supported by a heater base, so that the reaction tube 203 is installed vertically. A processing vessel (reaction vessel) is mainly composed of a reaction tube 203 and a manifold 209. A processing chamber 201 is formed in a cylindrical hollow portion inside the processing vessel. The processing chamber 201 is configured to be able to accommodate a plurality of wafers 200 as substrates. Note that the processing vessel is not limited to the above configuration, and in some cases only the reaction tube 203 is referred to as the processing vessel.

[0012] Nozzles 249a and 249b are provided in the processing chamber 201 to penetrate the sidewall of the manifold 209. Gas supply pipes 232a and 232b are connected to the nozzles 249a and 249b, respectively. In this manner, the reaction tube 203 is provided with two nozzles 249a and 249b and two gas supply pipes 232a and 232b, making it possible to supply multiple types of gases into the processing chamber 201.

[0013] Gas supply pipes 232a and 232b are respectively 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 of the gas flow. Gas supply pipes 232c and 232d, which supply inert gas, are connected to gas supply pipes 232a and 232b downstream of valves 243a and 243b. Gas supply pipes 232c and 232d are respectively provided with MFCs 241c and 241d and valves 243c and 243d in order from the upstream side of the gas flow.

[0014] 2, the nozzle 249a is provided in the space between the inner wall of the reaction tube 203 and the wafers 200, rising upward in the loading direction of the wafers 200 along the inner wall of the reaction tube 203 from the bottom to the top. That is, the nozzle 249a is provided on the side of the wafer arrangement area (loading area) where the wafers 200 are arranged (loaded), in an area horizontally surrounding the wafer arrangement area, and along the wafer arrangement area. That is, the nozzle 249a is provided on the side of the edge (periphery) of each wafer 200 loaded into the processing chamber 201, in a direction perpendicular to the surface (flat surface) of the wafer 200. A gas supply hole 250a for supplying gas is provided on the side of the nozzle 249a. The gas supply hole 250a opens toward the center of the reaction tube 203, allowing gas to be supplied toward the wafers 200. A plurality of gas supply holes 250a are provided from the bottom to the top of the reaction tube 203, each having the same opening area, and further provided at the same opening pitch.

[0015] A nozzle 249b is connected to the tip of the gas supply pipe 232b. The nozzle 249b is provided in a buffer chamber 237, which is a gas dispersion space. As shown in FIG. 2, the buffer chamber 237 is provided in a space having an annular shape in a plan view between the inner wall of the reaction tube 203 and the wafers 200, and in a portion extending from the lower part to the upper part of the inner wall of the reaction tube 203 along the stacking direction of the wafers 200. That is, the buffer chamber 237 is formed by a buffer structure 300 in a region horizontally surrounding the wafer arrangement region on the side of the wafer arrangement region and along the wafer arrangement region. The buffer structure 300 is made of an insulating material such as quartz, and gas supply ports 302 and 304 for supplying gas are formed in the arc-shaped wall surface of the buffer structure 300. 2 and 3, the gas supply ports 302 and 304 are opened toward the center of the reaction tube 203 at positions facing plasma generation regions 224a and 224b between rod-shaped electrodes 269 and 270 and between rod-shaped electrodes 270 and 271, respectively, and are capable of supplying gas toward the wafers 200. A plurality of gas supply ports 302 and 304 are provided from the bottom to the top of the reaction tube 203, each having the same opening area and arranged at the same opening pitch.

[0016] The nozzle 249b is installed along the inner wall of the reaction tube 203, rising upward in the stacking direction of the wafers 200. That is, the nozzle 249b is installed inside the buffer structure 300, in a region horizontally surrounding the wafer arrangement region where the wafers 200 are arranged, along the wafer arrangement region. That is, the nozzle 249b is installed on the side of the edge of the wafer 200 loaded into the processing chamber 201, in a direction perpendicular to the surface of the wafer 200. A gas supply hole 250b for supplying gas is provided on the side of the nozzle 249b. The gas supply hole 250b opens toward a wall surface formed radially from the arc-shaped wall surface of the buffer structure 300, allowing gas to be supplied toward the wall surface. This allows the reaction gas to be dispersed within the buffer chamber 237 and not directly sprayed onto the rod-shaped electrodes 269-271, thereby suppressing particle generation. Similar to the gas supply holes 250a, a plurality of gas supply holes 250b are provided from the bottom to the top of the reaction tube 203.

[0017] As described above, in this embodiment, gas is transported via nozzles 249a, 249b and the buffer chamber 237 arranged within a vertically elongated space that is annular in plan view and defined by the inner wall of the sidewall of the reaction tube 203 and the edges of the multiple wafers 200 arranged within the reaction tube 203, i.e., a cylindrical space. Then, gas is first ejected into the reaction tube 203 near the wafers 200 from gas supply holes 250a, 250b and gas supply ports 302, 304 that are opened in the nozzles 249a, 249b and the buffer chamber 237, respectively. The main flow of gas within the reaction tube 203 is parallel to the surface of the wafers 200, i.e., horizontally. This configuration allows gas to be uniformly supplied to each wafer 200, improving the uniformity of the film thickness formed on each wafer 200. The gas flowing over the surface of the wafer 200, i.e., the residual gas after the reaction, flows toward the exhaust port, i.e., the exhaust pipe 231 described below. However, the direction of the flow of this residual gas is appropriately determined depending on the position of the exhaust port, and is not limited to the vertical direction.

[0018] From the gas supply pipe 232a, a raw material containing a predetermined element, for example, a silane raw material gas containing silicon (Si) as the predetermined element, is supplied into the processing chamber 201 via the MFC 241a, the valve 243a, and the nozzle 249a.

[0019] The raw material gas refers to a raw material in a gaseous state, for example, a gas obtained by vaporizing a raw material that is in a liquid state at room temperature and normal pressure, or a raw material that is in a gaseous state at room temperature and normal pressure, etc. In this specification, the term "raw material" may mean a "liquid raw material that is in a liquid state," a "raw material gas that is in a gaseous state," or both.

[0020] The silane precursor gas may be, for example, a precursor gas containing Si and a halogen element, i.e., a halosilane precursor gas. The halosilane precursor is a silane precursor having a halogen group. The halogen element includes at least one element selected from the group consisting of chlorine (Cl), fluorine (F), bromine (Br), and iodine (I). That is, the halosilane precursor includes at least one halogen group selected from the group consisting of a chloro group, a fluoro group, a bromo group, and an iodo group. The halosilane precursor can also be considered a type of halide.

[0021] The halosilane precursor gas may be, for example, a precursor gas containing Si and Cl, i.e., a chlorosilane precursor gas. The chlorosilane precursor gas may be, for example, dichlorosilane (SiH2Cl2, abbreviated as DCS) gas.

[0022] A reactant (reactant) containing an element other than the above-mentioned predetermined element, such as a nitrogen (N)-containing gas as a reactive gas, is supplied from the gas supply pipe 232b into the processing chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b. For example, a hydrogen nitride gas can be used as the N-containing gas. The hydrogen nitride gas can be a substance composed of only the two elements N and H, and acts as a nitriding gas, i.e., an N source. For example, ammonia (NH) gas can be used as the hydrogen nitride gas.

[0023] An inert gas, for example, nitrogen (N2) gas, is supplied from the gas supply pipes 232c and 232d 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, respectively.

[0024] A raw material supply system serving as a first gas supply system is mainly composed of the gas supply pipe 232a, the MFC 241a, and the valve 243a. A reactant supply system serving as a second gas supply system is mainly composed of the gas supply pipe 232b, the MFC 241b, and the valve 243b. 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 raw material supply system, the reactant supply system, and the inert gas supply system are collectively referred to simply as the gas supply system (gas supply unit).

[0025] (Plasma generation unit) As shown in FIGS. 2 and 3 , three elongated rod-shaped electrodes 269, 270, and 271 made of a conductor are disposed in the buffer chamber 237 from the bottom to the top of the reaction tube 203 along the stacking direction of the wafers 200. Each of the rod-shaped electrodes 269, 270, and 271 is disposed parallel to the nozzle 249b. Each of the rod-shaped electrodes 269, 270, and 271 is protected by being covered from the top to the bottom by an electrode protection tube 275. The rod-shaped electrodes 269 and 271 disposed at both ends of the rod-shaped electrodes 269, 270, and 271 are connected to a high-frequency power supply 273 via a matching box 272, and the rod-shaped electrode 270 is connected to earth, which is a reference potential, and is therefore grounded. That is, the rod-shaped electrodes connected to the high-frequency power supply 273 and the grounded rod-shaped electrodes are arranged alternately, and the rod-shaped electrode 270 arranged between the rod-shaped electrodes 269 and 271 connected to the high-frequency power supply 273 is used as a grounded rod-shaped electrode in common with the rod-shaped electrodes 269 and 271. In other words, the grounded rod-shaped electrode 270 is arranged so as to be sandwiched between the rod-shaped electrodes 269 and 271 connected to adjacent high-frequency power supplies 273, and the rod-shaped electrodes 269 and 270, and similarly the rod-shaped electrodes 271 and 270, are configured to form pairs, respectively, to generate plasma. That is, the grounded rod-shaped electrode 270 is used in common with the rod-shaped electrodes 269 and 271 connected to the two high-frequency power supplies 273 adjacent to the rod-shaped electrode 270. Then, by applying radio frequency (RF) power from the high frequency power supply 273 to the rod-shaped electrodes 269, 271, plasma is generated in a plasma generation region 224a between the rod-shaped electrodes 269, 270 and a plasma generation region 224b between the rod-shaped electrodes 270, 271. The rod-shaped electrodes 269, 270, 271 and the electrode protection tube 275 mainly constitute a plasma generation unit (plasma generation device) serving as a plasma source. The matching box 272 and the high frequency power supply 273 may also be considered to be included in the plasma source. As will be described later, the plasma source functions as a plasma excitation unit (activation mechanism) that excites (activates) a gas into a plasma state, i.e., excites (activates) the gas into a plasma state.

[0026] The electrode protection tube 275 is configured so that each of the rod-shaped electrodes 269, 270, and 271 can be inserted into the buffer chamber 237 while being isolated from the atmosphere within the buffer chamber 237. If the O2 concentration inside the electrode protection tube 275 is similar to the O2 concentration in the outside air (atmosphere), the rod-shaped electrodes 269, 270, and 271 inserted into the electrode protection tube 275 will be oxidized by the heat from the heater 207. For this reason, the O2 concentration inside the electrode protection tube 275 can be reduced and the oxidation of the rod-shaped electrodes 269, 270, and 271 can be prevented by filling the inside of the electrode protection tube 275 with an inert gas such as N2 gas or by purging the inside of the electrode protection tube 275 with an inert gas such as N2 gas using an inert gas purge mechanism.

[0027] (Exhaust section) The reaction tube 203 is provided with an exhaust pipe 231 that exhausts the atmosphere inside the processing chamber 201. The exhaust pipe 231 is connected to a vacuum pump 246 as a vacuum exhaust device via a pressure sensor 245 as a pressure detector (pressure detection unit) that detects the pressure inside the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 as an exhaust valve (pressure adjustment unit). The APC valve 244 is configured to evacuate and stop the evacuation of the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operating. Furthermore, the pressure inside 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 operating. The exhaust pipe 231, the APC valve 244, and the pressure sensor 245 mainly constitute an exhaust system. The vacuum pump 246 may be considered to be included in the exhaust system. The exhaust pipe 231 is not limited to being provided in the reaction tube 203, but may be provided in the manifold 209 in the same manner as the nozzles 249a and 249b.

[0028] A seal cap 219 serving as a furnace port cover capable of airtightly closing the lower end opening of the manifold 209 is provided below the manifold 209. The seal cap 219 is configured to abut against the lower end of the manifold 209 from below in the vertical direction. The seal cap 219 is made of a metal such as SUS and is formed in a disk shape. An O-ring 220b serving as a sealing member that abuts against the lower end of the manifold 209 is provided on the upper surface of the seal cap 219. A rotation mechanism 267 for rotating a boat 217 (described later) is provided on the opposite side of the seal cap 219 from the processing chamber 201. 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 boat 217 to rotate the wafers 200. The seal cap 219 is configured to be vertically raised and lowered by a boat elevator 115 serving as a lifting mechanism that is vertically installed outside the reaction tube 203. The boat elevator 115 is configured to lift and lower the seal cap 219, thereby enabling the boat 217 to be loaded and unloaded into and from the processing chamber 201. The boat elevator 115 is configured as a transfer device (transfer mechanism) that transfers the boat 217, i.e., the wafers 200, into and out of the processing chamber 201. A shutter 219s is provided below the manifold 209 as a furnace port cover that can airtightly close the lower end opening of the manifold 209 while the seal cap 219 is being lowered by the boat elevator 115. The shutter 219s is made of a metal such as SUS and has a disk shape. An O-ring 220c is provided on the upper surface of the shutter 219s as a sealing member that abuts against the lower end of the manifold 209. The opening and closing operation (lifting and lowering operation, rotating operation, etc.) of the shutter 219s is controlled by a shutter opening and closing mechanism 115s.

[0029] (Board support) 1, a boat 217 serving as a substrate support is configured to support a plurality of wafers 200, for example, 25 to 200 wafers 200, in a horizontal position, aligned vertically with their centers aligned, i.e., arranged at predetermined intervals, in multiple stages. The boat 217 is made of a heat-resistant material such as quartz or SiC. Heat insulating plates 218, also made of a heat-resistant material such as quartz or SiC, are supported in multiple stages below the boat 217.

[0030] 2, a temperature sensor 263 serving as a temperature detector is installed inside the reaction tube 203. The temperature distribution inside the processing chamber 201 is adjusted to a desired value by adjusting the power supply to the heater 207 based on the temperature information detected by the temperature sensor 263. The temperature sensor 263 is installed along the inner wall of the reaction tube 203, similar to the nozzles 249a and 249b.

[0031] (Control device) Next, the control device will be described with reference to Fig. 4. As shown in Fig. 4, controller 121, which is a control unit (control device), is configured as a computer including a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, storage device 121c, and I / O port 121d. RAM 121b, storage device 121c, and I / O port 121d are configured to be able to exchange data with CPU 121a via internal bus 121e. An input / output device 122 configured as, for example, a touch panel, is connected to controller 121.

[0032] The storage device 121c is composed of, for example, a flash memory, an HDD (Hard Disk Drive), etc. Control programs for controlling the operation of the substrate processing apparatus, process recipes describing procedures and conditions for film formation processes (described later), etc., are readably stored in the storage device 121c. A process recipe is a combination of procedures for various processes (film formation processes) (described later) that are executed by the controller 121 to obtain a predetermined result, and functions as a program. Hereinafter, process recipes, control programs, etc. are collectively referred to simply as programs. A process recipe is also simply referred to as a recipe. In this specification, the term "program" may refer to a recipe alone, a control program alone, or both. The RAM 121b is configured as a memory area (work area) for temporarily storing programs, data, etc. read by the CPU 121a.

[0033] The I / O port 121d is connected to the above-mentioned MFCs 241a to 241d, valves 243a to 243d, pressure sensor 245, APC valve 244, vacuum pump 246, heater 207, temperature sensor 263, matching box 272, high-frequency power supply 273, rotation mechanism 267, boat elevator 115, shutter opening / closing mechanism 115s, etc.

[0034] The CPU 121a is configured to read and execute a control program from the storage device 121c, and also to read a recipe from the storage device 121c in response to an input of an operation command from the input / output device 122. The CPU 121a is configured to control the rotation mechanism 267, the flow rate adjustment of various gases by the MFCs 241a to 241d, the opening and closing of the valves 243a to 243d, the adjustment of the high-frequency power supply 273 based on impedance monitoring, the opening and closing of the APC valve 244 and the pressure adjustment by the APC valve 244 based on the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment of the heater 207 based on the temperature sensor 263, the forward / reverse rotation of the boat 217 by the rotation mechanism 267, the adjustment of the rotation angle and rotation speed, the lifting and lowering of the boat 217 by the boat elevator 115, and the like, in accordance with the contents of the read recipe.

[0035] The controller 121 can be configured by installing the above-mentioned program 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 media is used in this specification, it may include only the storage device 121c alone, only the external storage device 123 alone, or both. Note that 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.

[0036] (2) Substrate processing process Next, a process of forming a thin film on a wafer 200 as one step in the manufacturing process of a semiconductor device using the substrate processing apparatus 100 will be described with reference to Figures 5 and 6. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by a controller 121.

[0037] Here, an example will be described in which a step of supplying DCS gas as a source gas and a step of supplying plasma-excited NH3 gas as a reactive gas are performed a predetermined number of times (one or more times) asynchronously, i.e., without synchronization, to form a silicon nitride film (SiN film) as a film containing Si and N on the wafer 200. Also, for example, a predetermined film may be formed on the wafer 200 in advance. Also, a predetermined pattern may be formed on the wafer 200 or the predetermined film in advance.

[0038] In this specification, for convenience, the process flow of the film formation process shown in Fig. 6 may be expressed as follows: Similar notations will be used in the following explanations of modified examples and other embodiments.

[0039] (DCS → NH3 * )×n ⇒ SiN

[0040] In this specification, the term "wafer" may refer to the wafer itself or a laminate of the wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of a wafer" may refer to the surface of the wafer itself or the surface of a predetermined layer or the like formed on the wafer. In this specification, the phrase "forming a predetermined layer on a wafer" may 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. In this specification, the term "substrate" is also synonymous with the term "wafer".

[0041] (Loading step: S1) When a plurality of wafers 200 are loaded into the boat 217 (wafer charge), the shutter 219s is moved by the shutter opening / closing mechanism 115s to open the lower end opening of the manifold 209 (shutter open). Thereafter, as shown in Fig. 1, the boat 217 supporting the plurality of wafers 200 is lifted by the boat elevator 115 and carried into the processing chamber 201 (boat load). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0042] (Pressure and temperature adjustment step: S2) The inside of the processing chamber 201, i.e., the space in which the wafer 200 is present, is evacuated (reduced pressure exhausted) by the vacuum pump 246 so that the desired pressure (vacuum level) is reached. At this time, the pressure inside the processing chamber 201 is measured by a pressure sensor 245, and the APC valve 244 is feedback-controlled based on this measured pressure information. The vacuum pump 246 is kept in a constantly operating state at least until the film formation step described below is completed.

[0043] Furthermore, the wafers 200 in the processing chamber 201 are heated by the heater 207 to a desired temperature. At this time, the power supply to the heater 207 is feedback-controlled based on temperature information detected by the temperature sensor 263 so that the processing chamber 201 has a desired temperature distribution. The heating of the processing chamber 201 by the heater 207 continues at least until the film formation step, which will be described later, is completed. However, if the film formation step is performed at a temperature below room temperature, the heating of the processing chamber 201 by the heater 207 may not be performed. Note that if only processing is performed at such temperatures, the heater 207 is unnecessary and does not need to be installed in the substrate processing apparatus. In this case, the configuration of the substrate processing apparatus can be simplified.

[0044] Next, the rotation mechanism 267 starts to rotate the boat 217 and the wafers 200. The rotation mechanism 267 continues to rotate the boat 217 and the wafers 200 at least until the film formation step is completed.

[0045] (Deposition steps: S3, S4, S5, S6) Thereafter, the film forming step is carried out by sequentially executing steps S3, S4, S5, and S6.

[0046] (Source gas supply steps: S3, S4) In step S3, DCS gas is supplied to the wafer 200 in the processing chamber 201.

[0047] Valve 243a is opened to allow DCS gas to flow into gas supply pipe 232a. The DCS gas has its flow rate adjusted by MFC 241a, is supplied into processing chamber 201 from gas supply hole 250a via nozzle 249a, and is exhausted from exhaust pipe 231. At the same time, valve 243c is opened to allow N2 gas to flow into gas supply pipe 232c. The N2 gas has its flow rate adjusted by MFC 241c, is supplied into processing chamber 201 together with DCS gas, and is exhausted from exhaust pipe 231.

[0048] Furthermore, in order to prevent DCS gas from entering the nozzle 249b, the valve 243d is opened to allow N2 gas to flow into the gas supply pipe 232d. The N2 gas is supplied into the processing chamber 201 via the gas supply pipe 232b and the nozzle 249b, and is exhausted from the exhaust pipe 231.

[0049] The supply flow rate of DCS gas controlled by the MFC 241a is, for example, 1 sccm to 6000 sccm, preferably 2000 sccm to 3000 sccm. The supply flow rates of N2 gas controlled by the MFCs 241c and 241d are, for example, 100 sccm to 10000 sccm, respectively. The pressure in the processing chamber 201 is, for example, 1 Pa to 2666 Pa, preferably 665 Pa to 1333 Pa. The wafer 200 is exposed to the DCS gas for, for example, 1 second to 10 seconds, preferably 1 second to 3 seconds.

[0050] The temperature of the heater 207 is set so that the temperature of the wafer 200 is within a range of, for example, 0° C. to 700° C., preferably room temperature (25° C.) to 550° C., and more preferably 40° C. to 500° C. In this embodiment, by setting the temperature of the wafer 200 to 700° C. or less, further 550° C. or less, or further 500° C. or less, the amount of heat applied to the wafer 200 can be reduced, and the thermal history of the wafer 200 can be well controlled.

[0051] By supplying DCS gas to the wafer 200 under the above conditions, a Si-containing layer having a thickness of, for example, less than one atomic layer (one molecular layer) to several atomic layers (several molecular layers) is formed on the wafer 200 (the surface underlayer). The Si-containing layer may be a Si layer, a DCS adsorption layer, or both.

[0052] Here, a layer less than one atomic layer (one molecular layer) thick means an atomic layer (molecular layer) that is formed discontinuously, and a layer one atomic layer (one molecular layer) thick means an atomic layer (molecular layer) that is formed continuously. The Si-containing layer may include both a Si layer and an adsorption layer of DCS. However, as mentioned above, the Si-containing layer will be referred to as "one atomic layer," "several atomic layers," etc., and "atomic layer" will be used synonymously with "molecular layer."

[0053] If the thickness of the Si-containing layer formed on the wafer 200 exceeds several atomic layers, the modifying effect in the modifying process described below will not reach the entire Si-containing layer. Furthermore, the minimum thickness of the Si-containing layer that can be formed on the wafer 200 is less than one atomic layer. Therefore, it is preferable that the thickness of the Si-containing layer be less than one atomic layer to about several atomic layers.

[0054] After the Si-containing layer is formed, the valve 243a is closed to stop the supply of DCS gas into the processing chamber 201. At this time, the APC valve 244 is left open, and the processing chamber 201 is evacuated by the vacuum pump 246 to remove any unreacted DCS gas or reaction by-products remaining in the processing chamber 201 after contributing to the formation of the Si-containing layer (S4). Furthermore, the valves 243c and 243d are left open to maintain the supply of N2 gas into the processing chamber 201. The N2 gas acts as a purge gas. Note that step S4 may be omitted.

[0055] In addition to DCS gas, the source gases include tetrakisdimethylaminosilane (Si[N(CH3)2]4, abbreviated as 4DMAS) gas, trisdimethylaminosilane (Si[N(CH3)2]3H, abbreviated as 3DMAS) gas, bisdimethylaminosilane (Si[N(CH3)2]2H2, abbreviated as BDMAS) gas, bisdiethylaminosilane (Si[N(C2H5)2]2H2, abbreviated as BDEAS), bistertiarybutylaminosilane (SiH2[NH(C4H9)]2, abbreviated as BTBAS) gas, dimethylaminosilane (DMAS) gas, diethylaminosilane (DEAS) gas, dipropylaminosilane (DPAS) gas, and diisopropylaminosilane (DIPAS). Suitable examples of aminosilane precursor gases that can be used include: various aminosilane precursor gases such as monochlorosilane (SiH3Cl, abbreviated as MCS) gas, trichlorosilane (SiHCl3, abbreviated as TCS) gas, tetrachlorosilane (SiCl4, abbreviated as STC) gas, hexachlorodisilane (Si2Cl6, abbreviated as HCDS) gas, and octachlorotrisilane (Si3Cl8, abbreviated as OCTS) gas; and inorganic silane precursor gases that do not contain halogen groups, such as monosilane (SiH4, abbreviated as MS) gas, disilane (Si2H6, abbreviated as DS) gas, and trisilane (Si3H8, abbreviated as TS) gas.

[0056] As the inert gas, in addition to N2 gas, rare gases such as Ar gas, He gas, Ne gas, and Xe gas can be used.

[0057] (Reaction gas supply steps: S5, S6) After the film formation process is completed, plasma-excited NH 3 gas is supplied as a reactive gas to the wafer 200 in the processing chamber 201 (S5).

[0058] In this step, the valves 243b to 243d are controlled to open and close in the same manner as the valves 243a, 243c, and 243d in step S3. The flow rate of the NH3 gas is adjusted by the MFC 241b, and the NH3 gas is supplied into the buffer chamber 237 through the nozzle 249b. At this time, high frequency power is supplied between the rod-shaped electrodes 269, 270, and 271. The NH3 gas supplied into the buffer chamber 237 is excited into a plasma state (activated by plasma), and generates active species (NH3 * ) into the processing chamber 201 and is exhausted from the exhaust pipe 231.

[0059] The supply flow rate of NH3 gas controlled by the MFC 241b is, for example, 100 sccm to 10,000 sccm, preferably 1,000 sccm to 2,000 sccm. The high-frequency power applied to the rod-shaped electrodes 269, 270, and 271 is, for example, 50 W to 600 W. The pressure inside the processing chamber 201 is, for example, 1 Pa to 500 Pa. By using plasma, it is possible to activate the NH3 gas even when the pressure inside the processing chamber 201 is in this relatively low pressure range. The time during which activated species obtained by plasma-exciting the NH3 gas are supplied to the wafer 200, i.e., the gas supply time (irradiation time), is, for example, 1 second to 180 seconds, preferably 1 second to 60 seconds. Other processing conditions are the same as those in S3 described above.

[0060] By supplying NH3 gas to the wafer 200 under the above conditions, the Si-containing layer formed on the wafer 200 is plasma-nitrided. During this process, the energy of the plasma-excited NH3 gas breaks the Si-Cl and Si-H bonds in the Si-containing layer. The Cl and H atoms that have been released from their bonds with Si are released from the Si-containing layer. The Si atoms in the Si-containing layer, which now have dangling bonds due to the release of Cl and other atoms, then bond with N contained in the NH3 gas, forming Si-N bonds. As this reaction progresses, the Si-containing layer is transformed (modified) into a layer containing Si and N, i.e., a silicon nitride layer (SiN layer).

[0061] To convert a Si-containing layer into a SiN layer, it is necessary to supply plasma-excited NH3 gas. Even if NH3 gas is supplied in a non-plasma atmosphere, the energy required to nitride the Si-containing layer is insufficient in the temperature range mentioned above, making it difficult to sufficiently desorb Cl and H from the Si-containing layer or to sufficiently nitride the Si-containing layer to increase the Si-N bonds.

[0062] After the Si-containing layer is converted into a SiN layer, the valve 243b is closed to stop the supply of NH gas. The supply of high-frequency power between the rod-shaped electrodes 269, 270, and 271 is also stopped. The NH gas and reaction by-products remaining in the processing chamber 201 are then removed from the processing chamber 201 using the same processing procedures and conditions as in step S4 (S6). Note that step S6 may be omitted.

[0063] As the nitriding agent, that is, the NH3-containing gas to be plasma-excited, diazene (N2H2) gas, hydrazine (N2H4) gas, N3H8 gas, etc. may be used in addition to NH3 gas.

[0064] As the inert gas, in addition to N2 gas, for example, various rare gases exemplified in step S4 can be used.

[0065] (Performed a specified number of times: S7) The above-described steps S3, S4, S5, and S6 are performed in this order asynchronously, i.e., without synchronization, to form one cycle. This cycle is performed a predetermined number of times (n times), i.e., one or more times (S7), to form a SiN film of a predetermined composition and a predetermined thickness on the wafer 200. It is preferable to repeat the above-described cycle multiple times. That is, it is preferable to set the thickness of the SiN layer formed per cycle to be smaller than the desired thickness, and to repeat the above-described cycle multiple times until the thickness of the SiN film formed by stacking the SiN layers reaches the desired thickness.

[0066] (Atmospheric pressure recovery step: S8) After the above-described film formation process is completed, N2 gas as 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. As a result, the processing chamber 201 is purged with the inert gas, and gases remaining in the processing chamber 201 are removed from the processing chamber 201 (inert gas 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 (S8).

[0067] (Exit step: S9) Thereafter, the seal cap 219 is lowered by the boat elevator 115 to open the lower end of the manifold 209, and 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) (S9). After the boat unloading, the shutter 219s is moved, and the lower end opening of the manifold 209 is sealed by the shutter 219s via the O-ring 220c (shutter close). After being unloaded to the outside of the reaction tube 203, the processed wafers 200 are removed from the boat 217 (wafer discharging). After the wafer discharging, an empty boat 217 may be loaded into the processing chamber 201.

[0068] (3) Effects of this embodiment According to this embodiment, one or more of the following effects can be obtained. (a) According to this embodiment, by using multiple electrodes, it is possible to increase the electrode area and increase the amount of activated species generated and supplied to the wafer surface, thereby increasing the amount of activated species supplied to the wafer surface. (b) According to this embodiment, by using a plurality of electrodes, it is possible to reduce the output, and therefore it is possible to suppress the generation of particles. (c) According to this embodiment, by using an odd number of electrodes and making the grounding electrode common to the high-frequency power supply electrode, it is possible to reduce the installation space compared to when an even number of electrodes are used. (d) According to this embodiment, by providing three electrodes in the buffer chamber, the plasma generation region is divided into two locations, and by providing a gas supply port at the position corresponding to the generation region (between the electrodes), it is possible to increase the supply amount of activated species supplied to the wafer surface. This makes it possible to form a film in a short time and improve throughput. (e) By providing a plasma generating section within the buffer chamber, it becomes possible to supply a certain amount of activated species to the outside of the buffer chamber, thereby improving the uniformity within the wafer surface.

[0069] (Variation 1) Next, a modified example of this embodiment will be described with reference to Fig. 7. In this modified example, only the parts that are different from the above-described embodiment will be described below, and a description of the same parts will be omitted.

[0070] In the above-described embodiment, the buffer structure 300 is provided on the inner wall of the reaction tube 203, and the rod-shaped electrodes 269, 270, 271 and the nozzle 249b, each covered with an electrode protecting tube 275, are provided inside the buffer structure 300. However, in this modified example, a buffer structure 400 having the same configuration as the buffer structure 300 is further provided on the inner wall of the reaction tube 203.

[0071] Inside the buffer structure 400, rod-shaped electrodes 369, 370, and 371, each covered with an electrode protection tube 275, and a nozzle 249c are provided. The rod-shaped electrodes 369, 370, and 371, located at both ends, are connected to a high-frequency power supply 373 via a matching box 372, and the rod-shaped electrode 370 is connected to earth, which is a reference potential, and is therefore grounded. The nozzle 249c is connected to a gas supply pipe 232b and can supply the same gas as the nozzle 249b. A plurality of gas supply holes 250c for supplying gas are provided on the side of the nozzle 249c, extending from the bottom to the top of the reaction tube 203. The gas supply holes 250c open toward a wall surface formed radially from the arc-shaped wall surface of the buffer structure 400, allowing gas to be supplied toward the wall surface. Gas supply ports 402 and 404 are provided on the arc-shaped wall surface of the buffer structure 400 to supply gas into the buffer chamber 237. The gas supply ports 402 and 404 are open toward the center of the reaction tube 203 at positions facing the plasma generation regions 324a and 324b between the rod-shaped electrodes 369 and 370 and between the rod-shaped electrodes 370 and 371, respectively, and are provided in plurality from the bottom to the top of the reaction tube 203, each having the same opening area and arranged at the same opening pitch.

[0072] The buffer structure 300 and the buffer structure 400 are provided symmetrically with respect to a line passing through the centers of the exhaust pipe 231 and the reaction tube 203, with the exhaust pipe 231 in between. The nozzles 249a are provided at positions on the exhaust pipe 231 opposite each other with the wafer 200 in between. The nozzles 249b and 249c are provided at positions far from the exhaust pipe 231 in the buffer chamber 237.

[0073] In this modification, two buffer structures each equipped with a plasma generation unit are provided, and each buffer structure 300, 400 is equipped with a high-frequency power supply 273, 373 and a matching unit 272, 372. Each high-frequency power supply 273, 373 is connected to a controller 121, enabling plasma control for each buffer chamber 237 of the buffer structures 300, 400. Specifically, the controller 121 monitors the impedance of each plasma generation unit and independently controls the high-frequency power supplies 273, 373 to prevent uneven distribution of activated species in each buffer chamber 237. When the impedance is high, the controller 121 increases the power of the high-frequency power supply. This allows a sufficient amount of activated species to be supplied to the wafer even with low high-frequency power for each plasma generation unit, improving wafer in-plane uniformity. Furthermore, compared to a single plasma generation unit, plasma control is performed using a single high-frequency power supply for two plasma generation units. By providing a high-frequency power supply for each plasma generation unit, abnormalities such as a broken wire in each plasma generation unit can be easily identified. Furthermore, since the distance between the high frequency power supply and each electrode can be easily adjusted, it is possible to easily suppress differences in RF power application caused by differences in the distance between each electrode and the high frequency power supply.

[0074] (Variation 2) Next, a second modification of this embodiment will be described with reference to Fig. 8. In this second modification, three buffer structures each equipped with a plasma generating unit are provided on the inner wall of the reaction tube 203, and two nozzles for supplying raw material gas are provided.

[0075] Similar to the buffer structures 300 and 400, the buffer structure 500 includes rod-shaped electrodes 469, 470, and 471, each covered by an electrode protection tube 275, and a nozzle 249d. The rod-shaped electrodes 469 and 471 are connected to a high-frequency power supply via a matching box (not shown), and the rod-shaped electrode 470 is connected to earth (ground), which is a reference potential. The nozzle 249d is connected to a gas supply pipe 232b, enabling it to supply the same gas as the nozzle 249b. Gas supply ports 502 and 504 are provided between the electrodes on the arc-shaped wall surface of the buffer structure 500. The gas supply ports 502 and 504 are located between the rod-shaped electrodes 469 and 470 and between the rod-shaped electrodes 470 and 471, respectively, facing the plasma generation region, and are directed toward the center of the reaction tube 203. A plurality of gas supply ports are provided from the bottom to the top of the reaction tube 203, each with the same opening area and at the same opening pitch. Furthermore, the nozzle 249e is connected to the gas supply pipe 232a, and is capable of supplying the same gas as the nozzle 249a.

[0076] The buffer structure 300 and the buffer structure 400 are arranged symmetrically with respect to a line passing through the centers of the exhaust pipe 231 and the reaction tube 203, with the exhaust pipe 231 sandwiched between them. The buffer mechanism 500 is arranged at a position facing the exhaust pipe 231 with the wafer 200 sandwiched between them. Nozzles 249a and 249e for supplying source gases are arranged between the buffer structure 300 and the buffer structure 500, and between the buffer structure 400 and the buffer structure 500, respectively. Nozzles 249b, 249c, and 249d for supplying reaction gases are arranged on the same side in the buffer chamber 237, and the gas supply holes of the nozzles 249b, 249c, and 249d open toward wall surfaces formed radially from the arc-shaped wall surfaces of the buffer structures 300, 400, and 500, respectively.

[0077] The present modified example 2 also provides the same effects as those of the embodiment and modified example 1 described above.

[0078] (Variation 3) Next, a third modification of this embodiment will be described with reference to Fig. 9. In this third modification, four buffer structures each having a plasma generating unit are provided on the inner wall of the reaction tube 203.

[0079] Similar to the buffer structures 300, 400, and 500, rod-shaped electrodes 569, 570, and 571, each covered with an electrode protection tube 275, and a nozzle 249f are provided inside the buffer structure 600. The rod-shaped electrodes 569 and 571 are connected to a high-frequency power supply via a matching box (not shown), and the rod-shaped electrode 570 is connected to earth, which is the reference potential, and is thus grounded. The nozzle 249f is connected to a gas supply pipe 232b, and can supply the same gas as the nozzle 249b. Gas supply ports 602 and 604 for supplying gas are provided between the electrodes on the arc-shaped wall surface of the buffer structure 600. The gas supply ports 602 and 604 are opened to face the center of the reaction tube 203 at positions facing the plasma generation region between the rod-shaped electrodes 569 and 570 and between the rod-shaped electrodes 570 and 571, respectively, and are provided in plurality from the bottom to the top of the reaction tube 203, each having the same opening area and arranged at the same opening pitch.

[0080] The buffer structures 300, 400, 500, and 600 are provided at equal intervals. Nozzle 249a is provided at a position facing the exhaust pipe 231 across the wafer 200. Nozzle 249b and nozzle 249c are provided on the side of the buffer chamber 237 farther from the exhaust pipe 231. Nozzle 249d and nozzle 249f are provided on the exhaust pipe 231 side of the buffer chamber 237, and the gas supply holes of nozzles 249b, 249c, 249d, and 249f open toward wall surfaces formed radially from the arc-shaped wall surfaces of the buffer structures 300, 400, 500, and 600, respectively.

[0081] The third modification also provides the same effects as those of the embodiment and the first modification described above.

[0082] <Other Embodiments of the Present Invention> Next, another embodiment of the present invention will be described with reference to Figures 10 and 11. In this embodiment, only the parts that are different from the above-described embodiment will be described below, and a description of the same parts will be omitted.

[0083] In this embodiment, a gas supply pipe 232e that supplies a modifying gas is connected to the gas supply pipe 232b downstream of the valve 243b. The gas supply pipe 232e is provided with, in order from the upstream side of the gas flow, an MFC 241e and a valve 243e. A gas supply pipe 232f that supplies an inert gas is connected to the gas supply pipe 232e downstream of the valve 243e. The gas supply pipe 232f is provided with, in order from the upstream side of the gas flow, an MFC 241f and a valve 243f.

[0084] A modifying gas, for example, hydrogen (H2) gas, is supplied from the gas supply pipe 232e via the MFC 241e, the valve 243e, the gas supply pipe 232b, and the nozzle 249b into the processing chamber 201. An inert gas, for example, nitrogen (N2) gas, is supplied from the gas supply pipe 232f via the MFC 241f, the valve 243f, the gas supply pipe 232b, and the nozzle 249b into the processing chamber 201.

[0085] Then, as shown in FIG. 11, a step of supplying DCS gas as a raw material gas, a step of supplying plasma-excited NH3 gas as a reactive gas, and a step of supplying plasma-excited H2 gas as a modifying gas are carried out a predetermined number of times (one or more times) asynchronously, i.e., without synchronization, to form a silicon nitride film (SiN film) on the wafer 200 as a film containing Si and N.

[0086] (DCS → NH3 * →H2 * )×n ⇒ SiN

[0087] As described above, the present invention can be applied to a case where NH gas as a reactive gas is plasma-excited and supplied to the wafer from the nozzle 249b, and then H gas is plasma-excited and supplied, and the same effects as those of the above-described embodiment can be obtained. The present invention can also be applied to a case where there are multiple buffer structures, such as the case where there are two buffer structures in Modification 1 or the case where there are three buffer structures in Modification 2, and the same effects as those of the above-described embodiment and modifications can be obtained.

[0088] Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit and scope of the present invention.

[0089] For example, in the above embodiment, an example in which three electrodes are used as the plasma generating unit has been described, but the present invention is not limited to this and can be applied to cases in which an odd number of electrodes greater than three, such as five or seven, are used. For example, when configuring a plasma generating unit using five electrodes, a total of three electrodes, two electrodes located at the outermost positions and one electrode located at the center, can be connected to a high-frequency power supply, and the two electrodes located between the high-frequency power supplies can be connected to ground.

[0090] In the above-described embodiment, the number of electrodes on the high frequency power supply side is greater than the number of electrodes on the ground side, and the electrodes on the ground side are common to both the electrodes on the high frequency power supply side. However, this is not limiting, and the number of electrodes on the ground side may be greater than the number of electrodes on the high frequency power supply side, and the electrodes on the high frequency power supply side may be common to both the electrodes on the ground side. However, if the number of electrodes on the ground side is greater than the number of electrodes on the high frequency power supply side, it becomes necessary to increase the power applied to the electrodes on the high frequency power supply side, which will result in the generation of many particles. For this reason, it is preferable to set the number of electrodes on the high frequency power supply side to be greater than the number of electrodes on the ground side.

[0091] In the above embodiment, the gas supply ports 302, 304 formed in the buffer structure have the same opening area and are arranged at the same opening pitch. However, this is not limiting, and the opening area of ​​the gas supply port 302 may be larger than the opening area of ​​the gas supply port 304. As the number of electrodes in the buffer chamber 237 increases, the plasma generated between the rod-shaped electrodes 269, 270 located farther from the nozzle 249b is likely to be smaller than the plasma generated between the rod-shaped electrodes 270, 271 located closer to the nozzle 249b. For this reason, the opening area of ​​the gas supply port 302 located farther from the nozzle 249b may be larger than the opening area of ​​the gas supply port 304 located closer to the nozzle 249b.

[0092] In the above embodiment, when multiple buffer structures are provided, the same reactive gas is plasma-excited and supplied to the wafers. However, this is not limiting, and different reactive gases may be plasma-excited and supplied to the wafers in each buffer structure. This enables plasma control for each buffer chamber, making it possible to supply different reactive gases to each buffer chamber. Furthermore, compared to supplying multiple types of reactive gases using a single buffer structure, it is possible to eliminate unnecessary processes such as purging, thereby improving throughput.

[0093] In the above embodiment, an example has been described in which the reactant gas is supplied after the raw material is supplied. However, the present invention is not limited to this embodiment, and the order of supplying the raw material and the reactant gas may be reversed. In other words, the raw material may be supplied after the reactant gas is supplied. By changing the supply order, it is possible to change the film quality and composition ratio of the formed film.

[0094] In the above-described embodiments, an example of forming a SiN film on the wafer 200 has been described. The present invention is not limited to such an embodiment, and can be suitably applied to the case of forming a Si-based oxide film such as a silicon oxide film (SiO film), a silicon oxycarbide film (SiOC film), a silicon oxycarbonitride film (SiOCN film), or a silicon oxynitride film (SiON film) on the wafer 200, or the case of forming a Si-based nitride film such as a silicon carbonitride film (SiCN film), a silicon boronitride film (SiBN film), a silicon boron carbonitride film (SiBCN film), or a boron carbonitride film (BCN film) on the wafer 200. In these cases, in addition to an O-containing gas, a C-containing gas such as C3H6, an N-containing gas such as NH3, or a B-containing gas such as BCl3 can be used as the reactive gas.

[0095] The present invention is also suitably applicable to the case where an oxide film or nitride film containing a metal element such as titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), niobium (Nb), aluminum (Al), molybdenum (Mo), or tungsten (W), i.e., a metal oxide film or metal nitride film, is formed on the wafer 200. That is, the present invention is applicable to the case where a TiO film, TiN film, TiOC film, TiOCN film, TiON film, TiBN film, TiBCN film, ZrO film, ZrN film, ZrOC film, ZrOCN film, ZrON film, ZrBN film, ZrBCN film, HfO film, HfN film, HfOC film, HfOCN film, HfON film, HfBN film, HfBCN film, TaO film, TaOC film, TaOCN film, TaON film, TaBN film, TaBCN film, NbO The present invention can also be suitably applied to the formation of films such as NbN films, NbOC films, NbOCN films, NbON films, NbBN films, NbBCN films, AlO films, AlN films, AlOC films, AlOCN films, AlON films, AlBN films, AlBCN films, MoO films, MoN films, MoOC films, MoOCN films, MoON films, MoBN films, MoBCN films, WO films, WN films, WOC films, WOCN films, WON films, MWBN films, and WBCN films.

[0096] In these cases, for example, tetrakis(dimethylamino)titanium (Ti[N(CH3)2]4, abbreviated as TDMAT) gas, tetrakis(ethylmethylamino)hafnium (Hf[N(C2H5)(CH3)]4, abbreviated as TEMAH) gas, tetrakis(ethylmethylamino)zirconium (Zr[N(C2H5)(CH3)]4, abbreviated as TEMAZ) gas, trimethylaluminum (Al(CH3)3, abbreviated as TMA) gas, titanium tetrachloride (TiCl4) gas, hafnium tetrachloride (HfCl4) gas, etc. can be used as the source gas. The above-mentioned reaction gases can be used as the reaction gas.

[0097] That is, the present invention can be suitably applied to the formation of semi-metallic films containing semi-metallic elements and metallic films containing metallic elements. The process procedures and conditions for these film formation processes can be the same as those for the film formation processes shown in the above-described embodiment and modified examples. In these cases, the same effects as those of the above-described embodiment and modified examples can be obtained.

[0098] It is preferable that recipes used for film formation processes are individually prepared according to the process content and stored in the storage device 121c via an electric communication line or an external storage device 123. Then, when starting various processes, it is preferable that the CPU 121a appropriately selects an appropriate recipe according to the process content from among the multiple recipes stored in the storage device 121c. This makes it possible to versatilely and reproducibly form thin films of various film types, composition ratios, film qualities, and film thicknesses using a single substrate processing device. It also reduces the burden on the operator, prevents operational errors, and enables various processes to be started quickly.

[0099] The above-mentioned recipes do not necessarily have to be newly created, but may be prepared by modifying an existing recipe already installed in the substrate processing apparatus, for example. When modifying a recipe, the modified recipe may be installed in the substrate processing apparatus via an electric communication line or a recording medium on which the modified recipe is recorded. Alternatively, an existing recipe already installed in the substrate processing apparatus may be directly modified by operating the input / output device 122 provided in the existing substrate processing apparatus. [Explanation of symbols]

[0100] 200 wafers

Claims

[Claim 1] supplying dichlorosilane gas as a source gas to the substrate; supplying plasma-excited ammonia gas as a reactive gas to the substrate; supplying plasma-excited hydrogen gas as a modifying gas to the substrate; a silicon nitride film is formed on the substrate by performing a cycle of non-simultaneously performing the above a predetermined number of times.

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