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

Abstract

Provided is a technology that can control the decomposition rate of a processing gas supplied to a substrate.　A substrate disposed within a processing space is processed by (a) controlling this decomposition rate on the basis of a prescribed relationship between the residence time and decomposition rate of the processing gas supplied to the processing space.

Description

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

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

[0002] Patent Document 1 discloses a technology for supplying raw material gases and / or reactive gases at supply times that correspond to the concentration distribution of by-products formed on a substrate within the substrate surface as one step in the manufacturing process of a semiconductor device.

[0003] JP 2014-208883 A

[0004] However, when forming a film on a substrate, if the decomposition rate of the processing gas is high, the step coverage may deteriorate, and if the decomposition rate of the processing gas is low, the film formation rate may decrease.

[0005] The present disclosure provides techniques that allow for control of the decomposition rate of a process gas supplied to a substrate.

[0006] According to one aspect of the present disclosure, there is provided a technique for processing a substrate placed in a processing space by controlling the decomposition rate of a processing gas supplied into the processing space based on a predetermined relationship between the decomposition rate and residence time.

[0007] According to the present disclosure, it is possible to control the decomposition rate of the process gas supplied to the substrate.

[0008] FIG. 1 is a longitudinal cross-sectional view showing an outline of a substrate processing apparatus according to an embodiment of the present disclosure. FIG. 2 is a longitudinal cross-sectional view showing details of a substrate support unit shown in FIG. 1. FIG. 3(A) is a diagram showing a first gas supply system according to an embodiment of the present disclosure, FIG. 3(B) is a diagram showing a second gas supply system according to an embodiment of the present disclosure, and FIG. 3(C) is a diagram showing a third gas supply system according to an embodiment of the present disclosure. FIG. 4(A) is a diagram showing a processing chamber exhaust system according to an embodiment of the present disclosure, and FIG. 4(B) is a diagram showing a transfer chamber exhaust system according to an embodiment of the present disclosure. FIG. 5 is a schematic configuration diagram of a controller of a substrate processing apparatus according to an embodiment of the present disclosure, and is a block diagram showing a control system of the controller. FIG. 6 is a diagram showing a substrate processing sequence according to an embodiment of the present disclosure. FIG. 7 is a diagram showing the relationship between the residence time and the decomposition rate of the first gas. FIG. 8 is a diagram showing the relationship between the flow rate and the decomposition rate of the first gas. FIG. 9(A) is a diagram showing the relationship between elapsed time and the supply amount of the first gas. FIG. 9(B) is a diagram showing the relationship between elapsed time and the residence time of the first gas. 9C is a diagram showing the relationship between elapsed time and the flow rate of the first gas. 10A to 10C are diagrams showing examples of chemical structural formulas of the first gas according to an embodiment of the present disclosure.

[0009] Hereinafter, one embodiment of the present disclosure will be described mainly with reference to Figures 1 to 10. Note that all drawings used in the following description are schematic, and the dimensional relationships, ratios, etc. of elements shown in the drawings do not necessarily match those of reality. Furthermore, the dimensional relationships, ratios, etc. of elements between multiple drawings do not necessarily match.

[0010] (1) Configuration of the Substrate Processing Apparatus The configuration of the substrate processing apparatus 10 will be described with reference to FIG.

[0011] The substrate processing apparatus 10 includes a reaction tube storage chamber 206b, which includes a cylindrical reaction tube 210 extending vertically, a heater 211 as a heating unit (furnace body) installed on the outer periphery of the reaction tube 210, a gas supply structure 212 as a gas supply unit, and a gas exhaust structure 213 as a gas exhaust unit. The gas supply unit may include an upstream rectifier 214 and nozzles 223 and 224, which will be described later. The gas exhaust unit may include a downstream rectifier 215, which will be described later. Within the reaction tube 210, a section in which a substrate S is processed is referred to as a processing chamber 201. The processing chamber 201 may also be referred to as a processing space in which the substrate S is placed.

[0012] The gas supply structure 212 is provided upstream of the reaction tube 210 in the gas flow direction, and gas is supplied from the gas supply structure 212 into the reaction tube 210, and the gas is supplied horizontally to the substrate S. The gas exhaust structure 213 is provided downstream of the reaction tube 210 in the gas flow direction, and the gas inside the reaction tube 210 is exhausted from the gas exhaust structure 213. The gas supply structure 212, the inside of the reaction tube 210, and the gas exhaust structure 213 are horizontally connected to each other.

[0013] An upstream rectifier 214 for rectifying the flow of gas supplied from the gas supply structure 212 is provided on the upstream side of the reaction tube 210 between the reaction tube 210 and the gas supply structure 212. In addition, a downstream rectifier 215 for rectifying the flow of gas exhausted from the reaction tube 210 is provided on the downstream side of the reaction tube 210 between the reaction tube 210 and the gas exhaust structure 213. The lower end of the reaction tube 210 is supported by a manifold 216.

[0014] The reaction tube 210, the upstream rectifier 214, and the downstream rectifier 215 have a continuous structure and are made of a material such as quartz or SiC. These are made of a heat-transmitting member that transmits heat radiated from the heater 211. The heat from the heater 211 heats the substrate S and the gas.

[0015] The gas supply structure 212 is connected to a gas supply pipe 251 and a gas supply pipe 261 and includes a distribution unit 225 that distributes gas supplied from each gas supply pipe. A plurality of nozzles 223 and 224 are provided downstream of the distribution unit 225. The gas supply pipe 251 and the gas supply pipe 261 supply different types of gas as described below. The nozzles 223 and 224 are arranged in an up-down relationship or a side-by-side relationship. In this embodiment, the gas supply pipe 251 and the gas supply pipe 261 are collectively referred to as gas supply pipes 221. Each nozzle is also referred to as a gas discharge unit. The distribution unit 225 is configured to supply gas from the gas supply pipe 251 to the nozzle 223 and from the gas supply pipe 261 to the nozzle 224, respectively.

[0016] The upstream rectifier 214 has a housing 227 and a partition plate 226. The partition plate 226 extends horizontally and has a continuous structure without holes. The horizontal direction here refers to the direction toward the side wall of the housing 227. Multiple partition plates 226 are arranged vertically. The partition plates 226 are fixed to the side wall of the housing 227 and are configured to prevent gas from moving beyond the partition plate 226 to adjacent areas below or above.

[0017] Each partition plate 226 is provided at a position corresponding to each substrate S. Nozzles 223 and 224 are provided between the partition plates 226 and between the partition plates 226 and the housing 227. The gas discharged from the nozzles 223 and 224 has its flow adjusted by the partition plates 226 and is supplied to the surface of the substrate S. In other words, when viewed from the substrate S, the gas is supplied from the lateral direction of the substrate S.

[0018] The downstream straightening section 215 is configured so that when the substrate S is supported on the substrate support 300 described below, the ceiling is higher than that of the substrate S placed at the top, and the bottom is lower than that of the substrate S placed at the bottom of the substrate support 300.

[0019] The downstream rectification section 215 has a housing 231 and a partition plate 232. The partition plate 232 extends horizontally and has a continuous structure without holes. The horizontal direction here refers to the direction of the side wall of the housing 231. Furthermore, multiple partition plates 232 are arranged vertically. The partition plate 232 is fixed to the side wall of the housing 231 and is configured to prevent gas from moving beyond the partition plate 232 to adjacent areas below or above. A flange 233 is provided on the side of the housing 231 that comes into contact with the gas exhaust structure 213.

[0020] The partition plates 232 are provided at positions corresponding to the substrates S, respectively, and at positions corresponding to the partition plates 226. It is desirable that the corresponding partition plates 226 and 232 have the same height. Furthermore, when processing the substrates S, it is desirable that the height of the substrates S and the height of the partition plates 226 and 232 are aligned.

[0021] By arranging the partition plates 226 and 232 in the above-described positional relationship, the pressure loss in the vertical direction can be made uniform upstream and downstream of each substrate S. That is, as shown by the arrows in the figure, a horizontal gas flow can be reliably formed from the partition plate 226, over the substrate S, and to the partition plate 232, with vertical flow suppressed. Therefore, the difference in gas pressure over each substrate S can be reduced. This allows each substrate S to be processed uniformly. Furthermore, the difference in the residence time τ and / or flow velocity v of the first gas, which will be described later, over each substrate S can be reduced. This reduces the difference in the decomposition rate X of the first gas supplied to each substrate S.

[0022] The gas exhaust structure 213 is provided downstream of the downstream rectifier 215. The gas exhaust structure 213 is mainly composed of a housing 241 and an exhaust pipe connection part 242. A flange 243 is provided on the housing 241 on the downstream rectifier 215 side. The housings 231 and 241 have a structure in which the heights of their ceilings and bottoms are continuous. An exhaust hole 244 is formed on the downstream side of the housing 241, below or in the horizontal direction, through which gas that has passed through the downstream rectifier 215 is exhausted. The gas exhaust structure 213 is provided laterally of the reaction tube 210 and is a lateral exhaust structure that exhausts gas from the lateral direction of the substrate S.

[0023] The transfer chamber 217 is installed at the bottom of the reaction tube 210 via a manifold 216. In the transfer chamber 217, a vacuum transfer robot places (loads) a substrate S onto a substrate support (hereinafter, may be simply referred to as a boat) 300 via a substrate loading port, and the vacuum transfer robot also takes out the substrate S from the substrate support 300.

[0024] The transfer chamber 217 can accommodate a substrate support 300, a partition plate support 310, and a vertical drive mechanism 400 that drives the substrate support 300 and the partition plate support 310 (collectively referred to as a substrate holder) in the vertical and rotational directions. In Fig. 1, the substrate support 300 is shown raised by the vertical drive mechanism 400 and stored in the reaction tube 210.

[0025] The vertical drive mechanism 400 includes a rotation drive mechanism 430 that rotates the substrate support 300 and the partition plate support 310 together, and a boat up / down mechanism 420 that drives the substrate support 300 up and down relative to the partition plate support 310. The rotation drive mechanism 430 and the boat up / down mechanism 420 are fixed to a base flange 401 serving as a lid supported by a side plate 403 on a base plate 402. An O-ring 446 for vacuum sealing is installed on the upper surface of the base flange 401, and as shown in FIG. 1 , the base flange 401 is driven by a vertical drive motor 410 to raise the base flange 401 to a position where the upper surface of the base flange 401 is pressed against the transfer chamber 217, thereby maintaining an airtight seal inside the reaction tube 210. The support 440 fixed to the partition plate support 310 and the support 441 fixed to the substrate support 300 are connected by a vacuum bellows 443.

[0026] Next, the substrate support unit will be described in detail with reference to Figures 1 and 2. The substrate support unit is composed of at least a substrate support 300 that supports a substrate S, and is stored in the reaction tube 210. The substrate S is placed directly below the inner wall of the top plate of the reaction tube 210. The substrate support unit also transfers the substrate S using a vacuum transfer robot through a substrate loading port (not shown) inside the transfer chamber 217, and transports the transferred substrate S into the reaction tube 210 to perform processing to form a thin film on the surface of the substrate S. The substrate loading port is provided, for example, in a side wall of the transfer chamber 217. The substrate support unit may also include a partition plate support unit 310.

[0027] On the substrate support 300, a plurality of substrates S are placed at predetermined intervals in the vertical direction (perpendicular direction) by a plurality of support rods 315 supported by a base 311. The plurality of substrates S supported by the support rods 315 are separated from each other by disk-shaped partition plates 314 fixed (supported) at predetermined intervals on struts 313 supported by a partition plate support part 310. Here, the partition plates 314 are disposed directly below the substrates S and are disposed above and / or below the substrates S. The partition plates 314 separate the spaces between the substrates S. The predetermined intervals between the plurality of substrates S placed on the substrate support 300 are the same as the vertical intervals between the partition plates 314 fixed to the partition plate support part 310. The diameter of the partition plates 314 is formed to be larger than the diameter of the substrates S.

[0028] The base 311, the partition plate 314, and the plurality of support rods 315 are formed of a material such as quartz or SiC. Note that, although an example in which five substrates S are supported on the substrate support 300 is shown here, this is not limiting. For example, the substrate support 300 may be configured to be able to support approximately 5 to 50 substrates S. Note that the partition plate 314 is also called a separator.

[0029] In this specification, when a numerical range such as "5 to 50 sheets" is expressed, it means that the lower limit and upper limit are included in the range. Therefore, for example, "5 to 50 sheets" means "5 sheets or more and 50 sheets or less." The same applies to other numerical ranges.

[0030] In the process of forming a thin film on the substrate S, the partition plate 314 is preferably positioned at a height corresponding to the partition plate 226 and / or the partition plate 232. It is more preferable that the height of the partition plate 314 is aligned with that of the partition plate 226 and the partition plate 232.

[0031] By using such a substrate support portion, it becomes easier to form a horizontal gas flow in which vertical flow is suppressed across the partition plate 226, over the substrates S, and over the partition plate 232. This makes the difference in gas pressure over each substrate S uniform, allowing each substrate S to be processed uniformly. In addition, it is possible to reduce the difference in residence time τ and / or flow velocity v of the first gas, which will be described later, over each substrate S. This makes it possible to reduce the difference in decomposition rate X of the first gas supplied to each substrate S.

[0032] The partition plate support part 310 and the substrate support 300 are driven by the vertical drive mechanism part 400 in the vertical direction between the reaction tube 210 and the transfer chamber 217, and in the rotational direction around the center of the substrate S supported by the substrate support 300.

[0033] Next, the gas supply system will be described in detail with reference to Figures 3(A) to 3(C). As shown in Figure 3(A), a gas supply pipe 251 is provided with, in order from the upstream direction, a first gas source 252, a mass flow controller (MFC) 253 which is a flow rate controller (flow rate control part), a valve 275 which is an on-off valve, a tank 259 which is a storage part for storing gas, and a valve 254 which is an on-off valve.

[0034] The first gas source 252 is a source of a first gas containing a first element (also referred to as a "first element-containing gas"). The first gas is a source gas, i.e., one of the process gases.

[0035] A first gas supply system 250 (also referred to as a source gas supply system or a process gas supply system) is mainly configured by the gas supply pipe 251, the MFC 253, the valve 275, the tank 259, and the valve 254. The first gas supply system 250 may include a first gas source 252.

[0036] A gas supply pipe 255 is connected to the gas supply pipe 251 between the valve 275 and the tank 259. An inert gas source 256, an MFC 257, and an on-off valve 258 are provided in this order from the upstream direction in the gas supply pipe 255. An inert gas is supplied from the inert gas source 256.

[0037] A first inert gas supply system is mainly composed of the gas supply pipe 255, the MFC 257, and the valve 258. In the substrate processing step, the inert gas supplied from the inert gas source 256 acts as a purge gas for purging gas remaining in the reaction tube 210. The inert gas source 256 may be included in the first inert gas supply system. The first inert gas supply system may be added to the first gas supply system 250.

[0038] As shown in FIG. 3B, the gas supply pipe 261 is provided with a second gas source 262, an MFC 263, a valve 276, a tank 269, and a valve 264 in this order from the upstream direction.

[0039] The second gas source 262 is a source of a second gas containing a second element (hereinafter also referred to as a "second-element-containing gas"). The second gas is a gas different from the first gas and may be one of the process gases. The second gas may be considered as a reaction gas that reacts with a precursor of the first gas, which is a raw material gas, or as a modifying gas that modifies the surface of the substrate S.

[0040] A second gas supply system 260 (also referred to as a reactive gas supply system or a process gas supply system) is mainly composed of the gas supply pipe 261, the MFC 263, the valve 276, the tank 269, and the valve 264. The second gas supply system 260 may also include a second gas source 262.

[0041] A gas supply pipe 265 is connected to the gas supply pipe 261 between the valve 276 and the tank 269. An inert gas source 266, an MFC 267, and an on-off valve 268 are provided in this order from the upstream direction in the gas supply pipe 265. An inert gas is supplied from the inert gas source 266.

[0042] A second inert gas supply system is mainly composed of the gas supply pipe 265, the MFC 267, and the valve 268. In the substrate processing step, the inert gas supplied from the inert gas source 266 acts as a purge gas for purging gas remaining in the reaction tube 210. The inert gas source 266 may be included in the second inert gas supply system. The second inert gas supply system may be added to the second gas supply system 260.

[0043] 3C , the gas supply pipe 271 is provided with, in this order from the upstream direction, a third gas source 272, an MFC 273, and a valve 274. The gas supply pipe 271 is connected to the transfer chamber 217. When the transfer chamber 217 is to be filled with an inert gas atmosphere or when the transfer chamber 217 is to be placed in a vacuum state, an inert gas is supplied through the gas supply pipe 271.

[0044] The third gas source 272 is an inert gas source. A third gas supply system 270 is mainly configured by the gas supply pipe 271, the MFC 273, and the valve 274. The third gas source 272 may be included in the third gas supply system 270. The third gas supply system 270 is also referred to as a transfer chamber supply system.

[0045] 4A and 4B, the exhaust system will be described. The exhaust system 280, which exhausts the atmosphere in the reaction tube 210, has an exhaust pipe 281 communicating with the reaction tube 210, and is connected to the housing 241 via an exhaust pipe connector 242.

[0046] 4A , a vacuum pump 284 serving as a vacuum exhaust device is connected to an exhaust pipe 281 via a valve 282 and an APC (Auto Pressure Controller) valve 283 serving as a pressure regulator (pressure adjustment unit), so that the reaction tube 210 can be evacuated to a predetermined pressure (vacuum level). The exhaust pipe 281, the valve 282, and the APC valve 283 are collectively referred to as an exhaust system 280. The exhaust system 280 is also referred to as a processing chamber exhaust system. The vacuum pump 284 may be included in the exhaust system 280. An exhaust system 290 that exhausts the atmosphere in the transfer chamber 217 is connected to the transfer chamber 217 and has an exhaust pipe 291 that communicates with the interior of the transfer chamber 217.

[0047] 4B, a vacuum pump 294 is connected to the exhaust pipe 291 via a valve 292 and an APC valve 293, and is configured to evacuate the transfer chamber 217 to a predetermined pressure. The exhaust pipe 291, the valve 292, and the APC valve 293 are collectively referred to as an exhaust system 290. The exhaust system 290 is also referred to as a transfer chamber exhaust system. The exhaust system 290 may include the vacuum pump 294.

[0048] Next, a controller serving as a control section (control means) will be described with reference to Fig. 5. The substrate processing apparatus 10 has a controller 600 that controls the operation of each section of the substrate processing apparatus 10.

[0049] 5 shows an outline of the controller 600. The controller 600 is configured as a computer including a CPU (Central Processing Unit) 601, a RAM (Random Access Memory) 602, a storage device 603 as a storage unit, and an I / O port 604. The RAM 602, the storage device 603, and the I / O port 604 are configured to be able to exchange data with the CPU 601 via an internal bus 605.

[0050] The storage device 603 is configured by, for example, a flash memory, a hard disk drive (HDD), etc. A control program for controlling the operation of the substrate processing apparatus 10, a process recipe describing the procedures and conditions for substrate processing, etc. are readably stored in the storage device 603.

[0051] The process recipe functions as a program, which is a combination of procedures in a substrate processing step (described later) that are executed by the controller 600 to obtain a predetermined result. Hereinafter, the process recipe, control program, etc. are collectively referred to as simply a program. In this specification, the term "program" may refer to a process recipe alone, a control program alone, or both. The RAM 602 is configured as a memory area (work area) in which programs, data, etc. read by the CPU 601 are temporarily stored.

[0052] The I / O port 604 is connected to the above-mentioned vertical drive mechanism 400, heater 211, APC valves 283, 293, vacuum pumps 284, 294, MFCs 253, 257, 263, 267, 273, valves 254, 258, 264, 268, 274, 275, 276, rotation drive mechanism 430, etc.

[0053] The CPU 601 is configured to read and execute a control program from the storage device 603, and also to read a process recipe from the storage device 603 in response to input of an operation command from the input / output device 681. The CPU 601 is configured to control the lifting and lowering operation of the substrate support 300 by the vertical direction drive mechanism 400, the heating operation by the heater 211, the opening and closing operation of the APC valves 283 and 293, the start and stop of the vacuum pumps 284 and 294, the flow rate adjustment operation of various gases by the MFCs 253, 257, 263, 267, and 273, the opening and closing operation of the valves 254, 258, 264, 268, 274, 275, and 276, the rotation of the substrate support 300 by the rotation drive mechanism 430 and the adjustment of the rotation speed, etc., in accordance with the contents of the read process recipe.

[0054] The controller 600 according to this embodiment can be configured by installing the program into a computer using an external storage device 682 (e.g., a magnetic disk such as a hard disk, an optical disk such as a DVD, a magneto-optical disk such as an MO, or a semiconductor memory such as a USB memory) storing the program. The means for supplying the program to the computer is not limited to supplying the program via the external storage device 682. For example, the program may be supplied via a communication means such as the Internet or a dedicated line, without going through the external storage device 682. The storage device 603 and the external storage device 682 are configured as computer-readable recording media on which the program is recorded. Hereinafter, these are collectively referred to as recording media. In this specification, the term "recording medium" may refer to the storage device 603 alone, the external storage device 682 alone, or both.

[0055] Next, as one step in the semiconductor manufacturing process, a step of forming a thin film on a substrate S using the substrate processing apparatus 10 having the above-described configuration will be described with reference to Figures 6 to 10. In the following description, the operation of each part of the substrate processing apparatus 10 is controlled by a controller 600.

[0056] Here, a film formation process will be described in which a film is formed in a recess such as a trench or a hole of a substrate S using a first gas and a second gas. As the first gas, for example, disilicon hexachloride (Si ２ Cl ６ , hexachlorodisilane, abbreviated as HCDS) gas can be used.

[0057] The term "substrate" used in this specification may refer to the substrate itself or to a laminate of the substrate and a predetermined layer or film formed on its surface. The term "surface of the substrate" used in this specification may refer to the surface of the substrate itself or to the surface of a predetermined layer or the like formed on the substrate. When described in this specification, "forming a predetermined layer on a substrate" may mean forming a predetermined layer directly on the surface of the substrate itself or forming a predetermined layer on a layer or the like formed on the substrate. When used in this specification, the term "wafer" is synonymous with the term "substrate".

[0058] (S102) The transfer chamber pressure adjustment step S102 will be described. Here, the pressure inside the transfer chamber 217 is adjusted to the same level as that of a vacuum transfer chamber (not shown) adjacent to the transfer chamber 217. Specifically, the exhaust system 290 is operated to exhaust the atmosphere inside the transfer chamber 217 so that the atmosphere inside the transfer chamber 217 is at a vacuum level.

[0059] (S104) Next, the substrate carrying-in step S104 will be described. When the transfer chamber 217 reaches a vacuum level, the transfer of the substrate S begins. When the substrate S arrives at the vacuum transfer chamber, the gate valve is opened and the vacuum transfer robot carries the substrate S into the transfer chamber 217.

[0060] At this time, the substrate support 300 is placed on standby in the transfer chamber 217, and the substrates S are transferred to the substrate support 300. When a predetermined number of substrates S have been transferred to the substrate support 300, the vacuum transfer robot is retracted, and the vertical drive mechanism 400 raises the substrate support 300 to move the substrates S into the reaction tube 210. At this time, the surfaces of the substrates S are positioned so that they are flush with the height of the partition plates 226 and 232.

[0061] (S106) Next, the heating step S106 will be described. After the substrate S is carried into the reaction tube 210, the pressure inside the reaction tube 210 is controlled to a predetermined value, and the surface temperature of the substrate S is controlled to a predetermined value. When HCDS gas, for example, is used as the first gas, the temperature of the heater 211 is controlled so that the temperature of the substrate S is, for example, 100°C to 1500°C, preferably 200°C to 1000°C, and more preferably 400°C to 800°C. The pressure inside the reaction tube 210 may be, for example, 5 Pa to 100 kPa.

[0062] (S108) Next, the film treatment step S108 will be described. In the film treatment step S108, a predetermined film is formed on the substrate S having the recesses on its surface by performing a first gas supply step of flushing a first gas onto the substrate S, which will be described later, and a second gas supply step of flushing a second gas onto the substrate S, which will be described later, once or more times in accordance with the process recipe.

[0063] <First Gas Supply Process, Step S1> In this step, a first gas is flush-supplied to the processing chamber 201 inside which the substrate S is placed. Here, flush supply refers to supplying a large flow rate of gas into the reaction tube 210 in a short period of time.

[0064] Specifically, in this step, the first gas is stored in advance in a tank 259 provided in the gas supply pipe 251. When, for example, HCDS gas is used as the first gas, the pressure inside the tank 259 at this time is, for example, 100 to 100×10 ３ Pa, preferably 1.0 x 10 ３ ~80 x 10 ３ Pa, more preferably 5.0 × 10 ３ Pa ~ 60 x 10３ Let it be Pa.

[0065] When the first gas is supplied, the valve 254 provided downstream of the tank 259 between the tank 259 and the nozzle 223 is opened, and the first gas is supplied from the tank 259, in which the first gas is stored in advance, into the gas supply pipe 251. At this time, the pressure (total pressure) in the processing chamber 201 is set to, for example, 10 to 1.0×10 ３ Pa. Then, after a predetermined time has elapsed since the start of supply of the first gas, the valve 254 is closed to stop the supply of the first gas into the gas supply pipe 251. When, for example, HCDS gas is used as the first gas, the valve 254 is closed to stop the supply of the first gas into the gas supply pipe 251 after a time in the range of, for example, 0.1 to 10 seconds has elapsed.

[0066] The first gas is supplied in large quantities from the gas supply structure 212 into the reaction tube 210 in a short time via the upstream rectifier 214, and then exposed to the atmosphere and exhausted via the space above the substrate S, the downstream rectifier 215, the gas exhaust structure 213, and the exhaust pipe 281. At this time, the valve 282 and the APC valve 283 are open. Here, while the first gas is being supplied into the processing chamber 201, the valve 275 may be open or closed.

[0067] At this time, the decomposition rate of the first gas in the processing chamber 201 changes within a range of 0% to 100% as the residence time τ of the first gas changes. Here, when the decomposition rate includes 0%, a decomposition rate of 0% means that there is no change in the decomposition rate of the first gas over time. In other words, a state in which the first gas supplied into the processing chamber 201 is exhausted from the processing chamber 201 as the first gas is considered to be a decomposition rate of 0%. Furthermore, a state in which all of the first gas supplied into the processing chamber 201 is exhausted from the processing chamber 201 in a state other than as the first gas is considered to be a decomposition rate of 100%. This also applies to the following description.

[0068] Here, the residence time of a gas refers to a number that serves as an index of the time it takes for a gas supplied into the processing chamber 201 to be exhausted from the processing chamber 201. In the following description, the residence time of a first gas refers to the time it takes for the first gas supplied into the processing chamber 201 to be exhausted from the processing chamber 201. Alternatively, the residence time may be a number that serves as an index of the time it takes for a gas supplied into the processing chamber 201 to be exhausted from the processing chamber 201. Alternatively, the residence time may be a number that serves as an index of the time it takes for a gas that has reached the processing space to escape to the outside of the processing space.

[0069] In the following description, the residence time of the first gas is defined as the time from when the first gas reaches the substrate S until when it departs from the substrate S. Alternatively, the residence time of the first gas may be, for example, the time from when the first gas reaches the processing space until when it escapes from the processing space. Alternatively, the residence time of the first gas may be the time from when the first gas is discharged from a gas supply unit such as the nozzle 223 until when it reaches the exhaust hole 244. Alternatively, the residence time of the first gas may be the time from when the supply of the first gas starts to when the supply of the first gas ends, for example, the time from when the valve 254 downstream of the tank 259 is opened to when the valve 254 is closed, or the time from when a predetermined component of the substrate processing apparatus 10 starts or ends a predetermined operation. Alternatively, the residence time of the first gas may be the value obtained by dividing the diameter of the substrate S by the flow rate of the first gas above the substrate S. Alternatively, the residence time of the first gas may be the value obtained by dividing the volume of the processing chamber 201 by the volume of gas exhausted from the processing chamber 201 per unit time. Alternatively, the residence time of the first gas may be the time until the number of molecules of the first gas in the processing chamber at a certain point in time decreases to a predetermined value.

[0070] In this step, the residence time τ of the first gas is set according to the decomposition rate X of the first gas based on a predetermined relationship between the residence time τ of the first gas in the processing chamber 201 and the decomposition rate X of the first gas in the processing chamber 201. That is, by controlling the residence time τ of the first gas, the decomposition rate X of the first gas supplied to the substrate S is controlled.

[0071] Here, 10 to 1.0 × 10 ３The relationship between the residence time τ (seconds) of the first gas and the decomposition rate X (%) in the processing chamber 201 at a predetermined pressure within a range of Pa will be described with reference to Fig. 7. Fig. 7 is a semi-logarithmic graph in which the horizontal axis represents the residence time τ (seconds) of the first gas in logarithm, and the vertical axis represents the decomposition rate X (%) of the first gas.

[0072] As shown in FIG. 7 , the decomposition rate X of the first gas logarithmically increases as the residence time τ of the first gas in the processing chamber 201 increases. Here, according to FIG. 7 , for example, by setting the residence time τ of the first gas to τa, a first gas having a decomposition rate X of 50% can be supplied to the substrate S. Furthermore, by setting the residence time τ of the first gas to τa or less, a first gas having a decomposition rate X of 50% or less can be supplied to the substrate S. Furthermore, by setting the residence time τ of the first gas to τb or less, a first gas having a decomposition rate X of approximately 0% can be supplied to the substrate S. That is, the decomposition rate can be controlled based on a predetermined relationship between the decomposition rate of the first gas in the processing space and the residence time. In other words, the decomposition rate can be predicted based on a predetermined relationship between the decomposition rate of the first gas in the processing space and the residence time under certain conditions.

[0073] That is, by setting the value of the residence time τ of the first gas to be equal to or less than τ1, which is the first time at which the value of the decomposition rate X becomes the first decomposition rate X1, the value of the decomposition rate X can be controlled within a range (first range) that is equal to or less than the first decomposition rate X1. That is, by setting the residence time τ of the first gas shorter than a predetermined value, the decomposition rate of the first gas can be made lower than the decomposition rate of the first gas at a predetermined value of the residence time τ of the first gas. Furthermore, by setting the value of the residence time τ of the first gas to be equal to or less than the second time τ2, which is longer than the first time τ1, at which the value of the decomposition rate becomes the second decomposition rate X2, which is higher than the first decomposition rate X1, the value of the decomposition rate X can be controlled within a range (second range) that is equal to or less than the second decomposition rate X2. That is, by setting the residence time τ of the first gas longer than a predetermined value, the decomposition rate of the first gas can be made higher than the decomposition rate of the first gas at a predetermined value of the residence time τ of the first gas.

[0074] Here, the residence time τ of the first gas in the processing chamber 201 can be controlled by controlling the flow velocity v of the first gas in the processing chamber 201. That is, by increasing (also referred to as speeding up) the flow velocity v of the first gas, the residence time of the first gas in the processing chamber 201 can be shortened. Also, by decreasing (also referred to as slowing down) the flow velocity v of the first gas, the residence time of the first gas in the processing chamber 201 can be lengthened.

[0075] Here, the gas flow rate refers to a number that indicates the distance that the gas supplied into the processing chamber 201 moves per unit time. Alternatively, the gas flow rate may be a number that indicates the distance that the gas moves per unit time within the processing chamber 201. Alternatively, the gas flow rate may be a number that indicates the distance that the gas moves per unit time within the processing space.

[0076] In the following description, the flow velocity v of the first gas is defined as the average flow velocity of the first gas above the substrate S. Alternatively, the flow velocity v of the first gas may be the average flow velocity from one location (or region) to another location (or region), such as the average flow velocity from when the first gas is discharged from a gas supply unit such as the nozzle 223 into the processing chamber 201 until it reaches the exhaust hole 244. Alternatively, the average flow velocity of the first gas within the processing space may be used. Alternatively, the average flow velocity of the first gas within the processing chamber 201 may be used. Alternatively, instead of the average flow velocity of the first gas in the above example, the flow velocity of the first gas at a certain point on the substrate S, in the processing space, or in the processing chamber 201 may be used.

[0077] Furthermore, the residence time or flow rate of the first gas may be, for example, a value measured, calculated, or estimated using some means, or a value obtained by simulation.

[0078] Here, 10 to 1.0 × 10 ３ The relationship between the flow velocity v (m / sec) of the first gas and the decomposition rate X (%) in the processing chamber 201 at a predetermined pressure within a range of Pa will be described with reference to Fig. 8. The horizontal axis of Fig. 8 represents the flow velocity v (m / sec) of the first gas, and the vertical axis represents the decomposition rate X (%) of the first gas.

[0079] As shown in Fig. 8 , the decomposition rate X of the first gas decreases more gradually as the flow rate v in the processing chamber 201 increases. Here, according to Fig. 8 , for example, by setting the flow rate v of the first gas to va, a first gas having a decomposition rate X of 50% can be supplied to the substrate S. Furthermore, by setting the flow rate v of the first gas to va or higher, a first gas having a decomposition rate X of 50% or less can be supplied to the substrate S. That is, the decomposition rate can be controlled based on a predetermined relationship between the decomposition rate and the flow rate of the first gas in the processing space. In other words, the decomposition rate can be predicted based on a predetermined relationship between the decomposition rate and the flow rate of the first gas in the processing space under certain conditions.

[0080] That is, by setting the flow velocity v of the first gas to be equal to or greater than the first flow velocity v1, a first gas having a decomposition rate X equal to or less than a first decomposition rate X1 can be supplied to the substrate S. That is, by setting the flow velocity v of the first gas to be greater than a predetermined value, the decomposition rate of the first gas can be made lower than the decomposition rate of the first gas when the flow velocity v of the first gas is a predetermined value. Furthermore, by setting the flow velocity v of the first gas to be equal to or greater than a second flow velocity v2 that is smaller than the first flow velocity v1, a first gas having a decomposition rate X equal to or less than a second decomposition rate X2 that is higher than the first decomposition rate X1 can be supplied to the substrate S. That is, by setting the flow velocity v of the first gas to be smaller than a predetermined value, the decomposition rate of the first gas can be made higher than the decomposition rate of the first gas when the flow velocity v of the first gas is a predetermined value.

[0081] When HCDS gas, for example, is used as the first gas, by controlling the residence time τ of the first gas in this step within a range of 1.00 to 0.01 seconds, the decomposition rate X of the first gas can be set within a range of 0% to 100%. Furthermore, by controlling it within a range of 1.00 to 0.10 seconds, the decomposition rate X can be set within a range of 50% to 100%. Furthermore, by controlling it within a range of 0.10 to 0.01 seconds, the decomposition rate X can be set within a range of 0% to 50%. Furthermore, by controlling it to 0.01 seconds or longer, the decomposition rate X can be 0%, i.e., the first gas can be left undecomposed. Furthermore, by setting it to greater than 1.00 seconds, the decomposition rate X can be set to 100%.

[0082] When HCDS gas, for example, is used as the first gas, the decomposition rate X of the first gas can be set within a range of 0% to 50% by controlling the flow rate v of the first gas in this step to 5.0 m / s or more. Furthermore, by setting the flow rate v of the first gas to, for example, 10 m / s or more, the decomposition rate X can be set within a range of 0% to 25%. Furthermore, by setting the flow rate v of the first gas to, for example, 15 m / s or more, the decomposition rate X can be set within a range of 0% to 15%. Furthermore, by controlling the flow rate v to 20.0 m / s or more, the decomposition rate X can be set to 0%, i.e., the first gas can be left undecomposed. Furthermore, by setting the flow rate v to less than 5.0 m / s, the decomposition rate X can be set to 50 to 100%.

[0083] 9A, 9B, and 9C are schematic diagrams showing the changes over time in the supply amount, residence time τ, and flow velocity v of the first gas in the processing chamber 201 in this step, respectively.

[0084] In the following description, in this step, the period from the start of supply of the first gas until t1 seconds is referred to as the entry region a1, and the period from t1 seconds to t2 seconds is referred to as the exposure region a2. The end time t1 of the entry region a1 and the end time t2 of the exposure region a2 are set appropriately depending on the processing target and the processing content. As shown in FIG. 9A , the supply amount of the first gas is maximum at the start of supply of the first gas and then rapidly decreases in the entry region a1. Subsequently, the supply amount of the first gas gradually decreases in the exposure region a2. Furthermore, as shown in FIG. 9B , the residence time of the first gas in the entry region a1 rapidly increases, and subsequently, the residence time of the first gas in the exposure region a2 gradually increases. Furthermore, as shown in FIG. 9C , the flow velocity of the first gas is fastest (highest flow velocity) at the start of supply of the first gas and then rapidly decreases in the entry region a1. Subsequently, the flow rate of the first gas gradually decreases in the exposure area a2.

[0085] In the plunge region a1, the first gas flows at a relatively high flow rate, thereby shortening the residence time of the first gas within the processing chamber 201. That is, based on the relationship between the residence time of the first gas and the decomposition rate X of the first gas as shown in Fig. 7, a first gas having a low decomposition rate within a first range, for example, 0 to 50%, preferably 0 to 15%, and more preferably 0%, can be supplied to the substrate S.

[0086] Furthermore, in the plunge region a1, the flow rate of the first gas is relatively high and the supply rate of the first gas is relatively high. That is, a large flow rate of the first gas is supplied within a short time from the start of the supply of the first gas. In this case, the amount of one or both of the process gas and the first element-containing substance adsorbed on the surface of the substrate S increases during the period from the generation of reaction by-products described below until they are adsorbed on the surface of the substrate S. This improves the film formation rate. Furthermore, the amount of the first gas reaching the deep side of the recess within a short time from the start of the supply of the first gas increases. This increases the amount of one or both of the process gas and the first element-containing substance adsorbed on the surface of the substrate S during the period from the generation of reaction by-products until they are adsorbed on the substrate S. This improves the step coverage.

[0087] Furthermore, when forming a film in a recess (or groove, trench, or hole) formed on the substrate S, the more reactive the gas, the more likely it is to adsorb to the opening side of the recess and the less likely it is to adsorb to the deeper part of the recess. Therefore, when forming a film in a recess using a gas that decomposes to produce a more reactive substance (e.g., HCDS gas) as the first gas, shortening the residence time τ of the first gas and / or increasing the flow rate v of the first gas reduces the decomposition rate X, thereby improving step coverage. Note that controlling the residence time τ of the first gas and / or the flow rate v of the first gas so that the decomposition rate X of the first gas is 0% is preferable for improving step coverage. Furthermore, controlling the residence time τ of the first gas and / or the flow rate v of the first gas so that the decomposition rate X of the first gas is 0% in at least a portion of the entry region a1 is preferable for improving step coverage.

[0088] When using, for example, HCDS gas as the first gas, by setting the flow velocity of the first gas to, for example, 10 m / s or more in the intrusion region a1, the decomposition rate X can be set to a relatively low value of 0% to 25%, which is advantageous for improving step coverage. Furthermore, by setting the flow velocity of the first gas to, for example, 15 m / s or more, the decomposition rate can be set even lower, within the range of 0% to 15%, which is preferable for improving step coverage. Furthermore, by controlling the flow velocity to 20.0 m / s or more, the decomposition rate can be set to 0%, i.e., the first gas can be left undecomposed, which is even more preferable for improving step coverage. Furthermore, the film formation rate can be controlled by setting the flow velocity of the first gas to, for example, 5 to 10 m / s in the intrusion region a1 and setting the decomposition rate X to 25% to 50%.

[0089] Furthermore, in the exposure zone a2, the first gas flows at a low flow rate, thereby increasing the residence time of the first gas within the processing chamber 201. That is, based on the relationship between the residence time of the first gas and the decomposition rate X of the first gas as shown in Fig. 7, it is possible to supply to the substrate S a first gas having a high decomposition rate within the second range, for example, 15 to 100%, preferably 25 to 100%, and more preferably 50 to 100%. Therefore, the film formation rate can be controlled by the decomposition rate X.

[0090] When, for example, HCDS gas is used as the first gas, the decomposition rate of the first gas in the exposure zone a2 can be 50% or more when the flow rate of the first gas is, for example, 5.0 m / sec or less, 25% or more when the flow rate is 10 m / sec or less, and 15% or more when the flow rate is 15 m / sec or less. Therefore, the film formation rate can be controlled by the decomposition rate X.

[0091] That is, in this step, the first gas is flush-supplied, thereby making it possible to change the decomposition rate X of the first gas supplied to the substrate S. Furthermore, in this step, the first gas is flush-supplied, thereby controlling the flow rate of the first gas, thereby controlling the residence time of the first gas in the processing chamber 201, and making it possible to control the decomposition rate X of the first gas.

[0092] Furthermore, in this step, by flushing the first gas, the supply amount of the first gas can be increased at the start of supply of the first gas. When, for example, HCDS gas is used as the first gas, the supply amount of the first gas per unit time per substrate S may be, for example, 0.001 to 15 slm, preferably 0.05 to 10 slm, and more preferably 0.010 to 5 slm. If the supply amount is less than 0.001 slm, the partial pressure of the first gas in the processing chamber 201 may be reduced, resulting in a decrease in the film formation rate. If the supply amount is more than 15 slm, the increase in the partial pressure of the first gas in the processing chamber 201 may result in excessive decomposition of the first gas. If the supply amount is 0.001 to 15 slm, the flow rate can be changed by controlling the flow rate of the first gas while suppressing a decrease in the film formation rate and excessive decomposition of the first gas. Furthermore, when the flow rate is 0.05 to 10 slm, the flow velocity can be changed by controlling the flow rate of the first gas while further suppressing a decrease in the film formation rate and decomposition of the first gas.When the flow rate is 0.010 to 5 slm, the flow velocity can be changed by controlling the flow rate of the first gas while sufficiently suppressing a decrease in the film formation rate and excessive decomposition of the first gas.

[0093] Furthermore, by flush-supplying the first gas, the first gas whose pressure has been increased (boosted) in the tank 259 can be supplied into the processing chamber 201. This makes it possible to increase the flow rate of the first gas at the start of supply.

[0094] That is, this step includes a process of controlling the decomposition rate X of the first gas within a first range, e.g., 0 to 25%, and a process of controlling the decomposition rate X of the first gas within a second range, e.g., 25 to 100%. Furthermore, this step includes a flush supply of the first gas, whereby a low decomposition rate supply with a short residence time of the first gas is followed by a high decomposition rate supply with a long residence time. This allows for the continuous supply of first gases with different decomposition rates, which can prevent reaction by-products and the like from adsorbing to adsorption sites during purging or evacuation of the processing chamber 201. Furthermore, by supplying a large amount of a low decomposition rate gas in a short period of time followed by a high decomposition rate supply, it is possible to prevent reaction by-products, as described below, from adsorbing to adsorption sites.

[0095] In this way, in the process of controlling the decomposition rate X of the first gas within a first range, the step coverage performance can be improved, and in the process of controlling it within a second range that is at least partially different from the first range, the film formation rate can be improved. That is, improvements in both the step coverage performance and the film formation rate can be achieved.

[0096] As described above, in this step, the valve 282 and the APC valve 283 are open, and the reaction tube 210 is evacuated by the vacuum pump 284 while the first gas is being supplied into the processing chamber 201. This reduces the pressure in the processing chamber 201, increases the flow rate of the first gas, and shortens the residence time τ of the first gas in the processing chamber 201.

[0097] Furthermore, while the first gas is being supplied into the processing chamber 201, the valve 258 may be opened to allow a gas having a molecular weight smaller than that of the first gas to flow as a low-molecular-weight gas into the gas supply pipe 251 via the gas supply pipe 255. That is, a mixed processing gas containing a low-molecular-weight gas and the first gas may be supplied to the processing chamber 201. Here, the low-molecular-weight gas is preferably a gas that is low in reactivity with the first gas. Alternatively, an inert gas may be used as the low-molecular-weight gas. Furthermore, in order to prevent the first gas from entering the gas supply pipe 261, the valves 268 and 264 may be opened to allow an inert gas to flow into the gas supply pipe 261. In this case, the inert gas supplied from the gas supply pipe 261 may also be considered to be included in the mixed processing gas.

[0098] Here, the low molecular weight gas is, for example, nitrogen (N ２ ), helium (He), argon (Ar), etc. can be used.

[0099] By using the mixed process gas, the average molecular weight of the gas supplied in this step can be reduced. When the mixed process gas and the first gas, which have the same kinetic energy, are supplied under the same conditions, the mixed process gas, which has a smaller average molecular weight, will have a higher flow rate than the first gas. This allows the flow rate of the mixed process gas to be faster than the flow rate of the first gas.

[0100] Here, the amount of the low-molecular-weight gas in the mixed process gas may be, for example, 50 times or less. If the amount is greater than 50 times the amount of the first gas, the proportion of the low-molecular-weight gas in the mixed process gas increases, which may result in a decrease in the partial pressure of the first gas in the process chamber 201, leading to a decrease in the film formation rate and step coverage. If the amount of the low-molecular-weight gas in the mixed process gas is 50 times or less the amount of the first gas in the mixed process gas, the flow rate of the first gas can be controlled while suppressing the effects of a decrease in the partial pressure of the first gas. Furthermore, if the amount of the low-molecular-weight gas in the mixed process gas is, for example, 40 times or less, the effects of a decrease in the partial pressure of the first gas are further suppressed. Furthermore, if the amount is, for example, 30 times or less, the effects of a decrease in the partial pressure of the first gas are further suppressed, thereby controlling the decomposition rate and preventing a decrease in step coverage even for recesses with a high aspect ratio.

[0101] Furthermore, in at least a part of this step, the volume of the first gas supplied into the processing chamber 201 per unit time may be set to 0.0005 to 6 times, preferably 0.0015 to 3 times, and more preferably 0.0030 to 1 time the volume of the processing chamber 201. If the volume is less than 0.0005 times, the partial pressure of the first gas in the processing chamber 201 may be reduced, resulting in a decrease in the film formation rate. If the volume is more than 6 times, the increase in the partial pressure of the first gas in the processing chamber 201 may result in excessive decomposition of the first gas. If the volume is set to 0.0005 to 6 times, the flow rate can be changed by controlling the flow rate of the first gas while suppressing a decrease in the film formation rate and excessive decomposition of the first gas. Furthermore, if the volume is set to 0.0015 to 3 times, the flow rate can be changed by controlling the flow rate of the first gas while further suppressing a decrease in the film formation rate and decomposition of the first gas. When the ratio is 0.0030 to 1, the flow rate can be changed by controlling the flow rate of the first gas while sufficiently suppressing a decrease in the film formation rate and excessive decomposition of the first gas.

[0102] Furthermore, in at least a portion of this step, the volume of gas exhausted from the processing chamber 201 per unit time may be set to 50 to 4000 times, preferably 100 to 2000 times, and more preferably 300 to 1000 times the volume of the processing chamber 201. If the volume is less than 50 times, the time required for the pressure in the processing chamber 201 to increase after the first gas is supplied becomes shorter, which may make it difficult to maintain a high flow rate of the first gas. Therefore, it may be difficult to maintain a low decomposition rate of the first gas (e.g., a decomposition rate of the first gas of 25% or less, 15% or less, or 0% or less) for a certain period of time. If the volume is greater than 4000 times, the partial pressure of the first gas in the processing chamber 201 may be lowered, which may decrease the film formation rate. If the volume is set to 50 to 4000 times, it becomes easier to maintain a low decomposition rate of the first gas for a certain period of time while suppressing a decrease in the film formation rate of the first gas. Furthermore, when the ratio is set to 100 to 2000 times, it becomes easier to control the decomposition rate of the first gas to be kept low for a certain period of time while further suppressing a decrease in the film formation rate of the first gas. Furthermore, when the ratio is set to 300 to 1000 times, it becomes easier to control the decomposition rate of the first gas to be kept low for a certain period of time while sufficiently suppressing a decrease in the film formation rate of the first gas.

[0103] Furthermore, prior to this step and before starting the supply of the first gas into the processing chamber 201, the APC valve 283 may be adjusted to evacuate the reaction tube 210 using the vacuum pump 284. This increases the flow rate of the first gas, particularly the flow rate at the start of the supply, in other words, the flow rate in the above-mentioned entry region, and shortens the residence time τ of the first gas in the processing chamber 201.

[0104] The temperature inside the process chamber 201 in this step may be set higher than the decomposition temperature of the first gas, thereby increasing the reactivity of the first gas and improving the film formation rate, and shortening the residence time of the first gas in the process chamber 201 can prevent the decomposition rate of the first gas from becoming too high.

[0105] This step may be performed so that at least a portion of the adsorption sites on the surface of the substrate S become first element sites to which a first element-containing substance, which is a substance containing a first element contained in the first gas, is chemically adsorbed.

[0106] In the above-described embodiment, the first element may be, for example, silicon (Si) or germanium (Ge), which are Group 14 elements, or aluminum (Al), gallium (Ga), or indium (In), which are Group 13 elements. Alternatively, the first element may be, for example, a transition metal element. Examples of the transition metal element include titanium (Ti), zirconium (Zr), and hafnium (Hf), which are Group 4 elements; niobium (Nb) and tantalum (Ta), which are Group 5 elements; molybdenum (Mo) and tungsten (W), which are Group 6 elements; manganese (Mn), which is Group 7 element; ruthenium (Ru), which is Group 8 element; cobalt (Co), which is Group 9 element; and nickel (Ni), which is Group 10 element.

[0107] As the first gas, for example, a Si-containing gas containing Si as the first element can be used. As the Si-containing gas, for example, a gas containing Si and chlorine (Cl) can be used. As the Si- and Cl-containing gas, for example, a source gas containing Si-Si bonds, such as HCDS gas shown in FIG. 10A, can be used. As shown in FIG. 10A, HCDS gas contains Si and a chloro group (chloride) in its chemical structural formula (in one molecule). Furthermore, as the Si- and Cl-containing gas, for example, 1,1,2,2-tetrachloro-1,2-dimethyldisilane ((CH ３ ) ２ Si ２ Cl ４ , abbreviated as TCDMDS) and 1,2-dichloro-1,1,2,2-tetramethyldisilane ((CH ３ ) ４ Si ２ Cl ２, abbreviated as DCTMDS) may be used. As shown in FIG. 10B, TCDMDS has a Si-Si bond and further includes a chloro group and an alkylene group. As shown in FIG. 10C, DCTMDS has a Si-Si bond and further includes a chloro group and an alkylene group. One or more of these may be used as the first gas.

[0108] The inert gas is, for example, N ２ In the inert gas, one or more of these gases can be used, such as argon gas, argon (Ar) gas, helium (He) gas, neon (Ne) gas, xenon (Xe) gas, etc. This also applies to the steps described below.

[0109] When HCDS gas is used as the first gas, for example, when the HCDS gas is decomposed and the bonds between the Si bonds are broken, SiCl ４ and SiCl ２ That is, HCDS gas decomposes as shown below.

[0110] HCDS(Si ２ Cl ６ ) → SiCl ４ +SiCl ２

[0111] SiCl ４ and SiCl ２ Since HCl is more reactive than HCDS, the decomposition rate of HCDS is high, and the reaction progresses as the decomposition of HCDS progresses. ３ ) gas, SiCl ２ and SiCl ４ Each of these reacts with an NH group, which will be described later, to form a SiN layer, and at this time, reaction by-products such as hydrogen chloride (HCl) are generated.

[0112] At least some of the adsorption sites on the surface of the substrate S become Si sites where Si-containing substances, that is, Si-containing substances, are chemically adsorbed, but reaction by-products such as HCl are adsorbed to the adsorption sites on the substrate S and inhibit the adsorption of the Si-containing substances. In this step, by flushing the first gas, a large amount of the first gas is supplied to the substrate S in a short time after the start of supply, thereby reducing the number of adsorption sites on the substrate S for reaction by-products such as HCl and increasing the amount of adsorption of the Si-containing substances. This makes it possible to improve the film formation rate and step coverage performance.

[0113] <Purge, Step S2> In this step, a purge gas is supplied to the processing chamber 201 in which the substrate S is placed. That is, after the flush supply of the first gas in step S1, Si-containing substances that have not been adsorbed to the adsorption sites and reaction by-products that have re-adsorbed on the surface of the substrate S are desorbed and removed from the reaction tube 210.

[0114] Specifically, with valve 254 open, valve 275 is closed, and valves 258, 268, and 264 are opened to supply an inert gas as a purge gas into gas supply pipes 251 and 261 via gas supply pipes 255 and 265, while valve 282 and APC valve 283 of exhaust pipe 281 are left open and the reaction tube 210 is evacuated to a vacuum by vacuum pump 284.

[0115] <Second Gas Supply Process, Step S3> Next, a second gas that reacts with the first gas is supplied to the processing chamber 201 inside which the substrate S is placed. Specifically, in this step, the second gas is stored in advance in a tank 269 provided in the gas supply pipe 261. Then, when supplying the second gas, a valve 264 provided downstream of the tank 269 between the tank 269 and the nozzle 224 is opened, and the second gas is supplied into the gas supply pipe 261 from the tank 269 in which the second gas has been stored in advance. Then, after a predetermined time has elapsed since the start of the supply of the second gas, the valve 264 is closed to stop the supply of the second gas into the gas supply pipe 261.

[0116] The second gas is supplied in large quantities from the gas supply structure 212 into the reaction tube 210 in a short time via the upstream rectifier 214, and then exposed to the atmosphere, and is exhausted via the space above the substrate S, the downstream rectifier 215, the gas exhaust structure 213, and the exhaust pipe 281. At this time, the valve 282 and the APC valve 283 are in an open state. Here, while the second gas is being supplied into the processing chamber 201, the valve 276 may be in an open state or a closed state. Also, the valve 268 is opened, and N is introduced into the gas supply pipe 261 via the gas supply pipe 265. ２ An inert gas such as a gas may be flowed through the gas supply pipe 251. Furthermore, in order to prevent the second gas from entering the gas supply pipe 251, the valves 258 and 254 may be opened to allow the inert gas to flow through the gas supply pipe 251. At this time, a large amount of the second gas is supplied at once from the side of the substrate S in a horizontal direction relative to the substrate S via the gas supply structure 212 that is in communication with the inside of the reaction tube 210.

[0117] The temperature inside the process chamber 201 at this time may be set to be higher than the decomposition temperature of the second gas. In this step, similar to step S1 described above, the decomposition rate X of the second gas inside the process chamber 201 may be controlled by setting the residence time τ of the second gas based on a predetermined relationship between the decomposition rate X of the second gas inside the process chamber 201 and the residence time τ of the second gas inside the process chamber 201.

[0118] The second gas may be, for example, a gas containing a second element different from the first gas. The second element is, for example, any one of N, oxygen (O), and carbon (C). The second gas may be, for example, a gas containing hydrogen (H) and N. The H and N-containing gas may be, for example, ammonia (NH ３ ) gas, diazene (N ２ H ２ ) gas, hydrazine (N ２ H ４ ) gas, N ３ H ８ The second gas may be a hydrogen nitride gas containing an N—H bond, such as a nitrogen-containing gas, etc. The second gas may be one or more of these.

[0119] <Purge, Step S4> In this step, a purge gas is supplied to the processing chamber 201 in which the substrate S is placed, using the same processing procedure as in step S2. That is, after the flush supply of the second gas in step S3, the second gas that has not been adsorbed to the adsorption sites and the reaction by-products that have been generated by the reaction with the second gas and have re-adsorbed onto the surface of the substrate S are desorbed and removed from the reaction tube 210.

[0120] Specifically, with valve 264 open, valve 276 is closed, and valves 268, 258, and 254 are opened to supply an inert gas as a purge gas into gas supply pipes 251 and 261 via gas supply pipes 255 and 265, while valve 282 and APC valve 283 of exhaust pipe 281 are left open and the reaction tube 210 is evacuated to a vacuum by vacuum pump 284. This makes it possible to suppress the reaction between the first gas and the second gas in the vapor phase present in the reaction tube 210.

[0121] (Performed a Predetermined Number of Times) A ​​cycle of sequentially and non-simultaneously performing the above-described first gas supply step and second gas supply step is performed a predetermined number of times (n times, where n is an integer of 1 or greater), to form a film of a predetermined thickness on the substrate S having a recess. For example, when HCDS gas is used as the first gas and a gas containing H and N is used as the second gas, a SiN film is formed. This improves the step coverage performance on the substrate S having a recess, and allows the formation of a film with an increased film formation rate.

[0122] (S110) Next, the substrate unloading step S110 will be described. In S110, the processed substrate S is unloaded from the transfer chamber 217 in the reverse order of the substrate loading step S104 described above.

[0123] (S112) Next, the judgment S112 will be described. Here, it is judged whether or not the substrate has been processed the predetermined number of times. If it is judged that the substrate has not been processed the predetermined number of times, the process returns to the substrate carry-in step S104, and the next substrate S is processed. If it is judged that the substrate has been processed the predetermined number of times, the process ends.

[0124] Although the gas flow formation is described as horizontal in the above, it is sufficient that the main gas flow is formed in the horizontal direction overall, and the gas flow may be diffused in the vertical direction as long as it does not affect the uniform processing of multiple substrates.

[0125] Furthermore, although expressions such as "same level," "equivalent," and "equal" are used above, it goes without saying that these include things that are essentially the same.

[0126] Other Embodiments Although the embodiment of this aspect has been specifically described above, the present invention is not limited to this and various modifications are possible without departing from the spirit of the invention.

[0127] In the above embodiment, the tank 259 is provided in the first gas supply system 250, but the present embodiment is not limited to this. That is, the first gas supply system 250 may not include the tank 259, and the first gas may be supplied by a method other than flush supply. Even in this case, the same effects as those of the above embodiment can be obtained.

[0128] Similarly, although the second gas supply system 260 described above is provided with the tank 269, this embodiment is not limited to this. That is, the second gas supply system 260 may not be provided with the tank 269, and the second gas may be supplied by a method other than flush supply. Even in this case, the same effects as those of the embodiment described above can be obtained.

[0129] In the above-described embodiment, a film is formed on the substrate S using the first gas and the second gas in the film formation process performed by the substrate processing apparatus, but the embodiment is not limited to this. That is, other types of gases may be used as the process gases used in the film formation process to form other types of thin films. Furthermore, the embodiment can be applied even when three or more types of process gases are used.

[0130] In addition, in the above-described embodiment, a film formation process is given as an example of a process performed by the substrate processing apparatus, but the present embodiment is not limited to this, and can be applied to film formation processes other than the film formation processes given as examples in the above-described embodiment.

[0131] In the above-described 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-described embodiment and can be suitably applied, for example, to a case where a film is formed using a single-wafer substrate processing apparatus that processes one or several substrates at a time. In the above-described embodiment, an example of forming a film using a substrate processing apparatus having a hot-wall processing furnace has been described. The present disclosure is not limited to the above-described embodiment and can be suitably applied to a case where a film is formed using a substrate processing apparatus having a cold-wall processing furnace.

[0132] When using these substrate processing apparatuses, each process can be performed using the same processing procedures and conditions as in the above-described embodiments and modifications, and the same effects as in the above-described embodiments and modifications can be obtained.

[0133] The above-described embodiments and modifications may be used in combination as appropriate. The processing procedures and processing conditions in such a case may be the same as those of the above-described embodiments and modifications, for example.

[0134] S substrate 201 processing chamber

Claims

1. (a) processing a substrate disposed in a processing space by controlling a decomposition rate of a processing gas supplied into the processing space based on a predetermined relationship between the decomposition rate and a residence time of the processing gas; A substrate processing method comprising:

2. In (a), (a1) controlling the value of the decomposition rate within a first range; (a2) controlling the value of the decomposition rate within a second range that is at least partially different from the first range; The substrate processing method according to claim 1 , further comprising the steps of:

3. In (a), The value of the decomposition rate is controlled to be equal to or less than the first decomposition rate by setting the value of the residence time to be equal to or less than a first time at which the value of the decomposition rate becomes a first decomposition rate. The substrate processing method according to claim 1 .

4. In (a), (a1) controlling the value of the decomposition rate to be equal to or less than the first decomposition rate by setting the value of the residence time to be equal to or less than a first time at which the value of the decomposition rate becomes equal to or less than the first decomposition rate; (a2) controlling the value of the residence time to a second time longer than the first time so that the value of the decomposition rate becomes a second decomposition rate higher than the first decomposition rate, thereby controlling the value of the decomposition rate to be equal to or less than the second decomposition rate; The substrate processing method according to claim 1 , further comprising the steps of:

5. A substrate processing method as described in claim 4, wherein (a) comprises performing (a2) after (a1).

6. 6. The substrate processing method according to claim 1, wherein in (a), the processing space is evacuated before starting to supply the processing gas to the processing space.

7. 6. The substrate processing method according to claim 1, wherein in (a), the processing space is evacuated while the processing gas is being supplied to the processing space.

8. 6. The substrate processing method according to claim 1, wherein in (a), the supply amount of the processing gas is maximized at the start of supply of the processing gas.

9. 6. The substrate processing method according to claim 1, wherein in (a), the processing gas is supplied to the processing space at a pressurized state.

10. The substrate processing method according to claim 9, wherein in (a), the processing gas is pressurized to 100 to 100×10 3 Pa and then supplied into the processing space.

11. 6. The substrate processing method according to claim 1, wherein in (a), the processing gas is mixed with a low-molecular-weight gas having a molecular weight smaller than that of the processing gas and then supplied to the processing space.

12. 6. The substrate processing method according to claim 1, wherein in (a), the temperature in the processing space is higher than a decomposition temperature of the processing gas.

13. 6. The substrate processing method according to claim 1, wherein the processing gas is hexachlorodisilane gas.

14. 6. The substrate processing method according to claim 1, further comprising: (b) supplying a reactive gas that reacts with the processing gas into the processing space.

15. A substrate processing method described in any one of claims 1 to 5, wherein (a) supplies the processing gas having a decomposition rate of 0% to the substrate, and then supplies the processing gas having a decomposition rate of 15 to 100% to the substrate.

16. A substrate processing method according to claim 1, wherein in (a), 0.001 to 15 slm of the processing gas is supplied to one of the substrates.

17. A substrate processing method described in any one of claims 1 to 5, wherein (a) evacuates the processing vessel.

18. (a) processing a substrate disposed in a processing space by controlling a decomposition rate of a processing gas supplied into the processing space based on a predetermined relationship between the decomposition rate and a residence time of the processing gas; A method for manufacturing a semiconductor device having the above structure.

19. a processing space in which the substrate is disposed; a processing gas supply system for supplying a processing gas to the processing space; (a) a control unit configured to be able to control the processing gas supply system so as to perform a process of controlling the decomposition rate based on a predetermined relationship between the decomposition rate of the processing gas in the processing space and a residence time of the processing gas; A substrate processing apparatus having:

20. (a) processing a substrate disposed in a processing space by controlling a decomposition rate of a processing gas supplied into the processing space based on a predetermined relationship between the decomposition rate and a residence time of the processing gas; A program that causes a computer to execute a procedure having the steps.