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

Abstract

The present invention can improve the step coverage performance of a film formed on a substrate having a recess.　This method for manufacturing a semiconductor device comprises: (a) a step for supplying, into a recess in a substrate provided with an adsorption site on a surface thereof, a feedstock gas at a speed faster than the adsorption speed at which a precursor of the feedstock gas is adsorbed onto the adsorption site; (b) a step for supplying a purge gas into the recess; and (c) a step for supplying the feedstock gas into the recess at a speed slower than the aforementioned adsorption speed.

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a technique for making the flow velocity of a source gas flowing in a direction parallel to the surface of a substrate greater than the flow velocity of an inert gas flowing in a direction parallel to the surface of the substrate in a step of purging the inside of a processing vessel by supplying an inert gas or a hydrogen-containing gas together with the source gas toward the substrate as one step of a manufacturing process of a semiconductor device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In recent years, due to the reduction of the cell area caused by the miniaturization of devices, the aspect ratio of recesses such as grooves formed on a substrate has increased, and it has become necessary to improve the step coverage performance such as film formation on a substrate having deeper recesses. In order to improve the step coverage performance, it is necessary to supply gas sufficiently to the lower part of the recess. However, if an attempt is made to supply gas sufficiently to the lower part of the recess due to an increase in the aspect ratio, the upper part of the device will be supplied with too much processing gas, and the step coverage performance will not be improved. In order to improve the step coverage performance, it is necessary to suppress the supply amount of the processing gas to the upper part of the device while supplying gas sufficiently to the lower part of the recess.

[0005] An object of the present disclosure is to provide a technique capable of improving the step coverage performance of a film formed on a substrate having a recess.

Means for Solving the Problems

[0006] According to one aspect of the present disclosure, (a) a step of supplying a raw material gas to a recess of a substrate having adsorption sites on its surface at a rate faster than the adsorption rate at which a precursor of the raw material gas is adsorbed on the adsorption sites; (b) a step of supplying a purge gas to the recess; (c) a step of supplying the raw material gas to the recess at a rate slower than the adsorption rate; A technique having the above is provided.

Effects of the Invention

[0007] According to the present disclosure, the step coverage performance of a film formed on a substrate having recesses can be improved.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0009] Hereinafter, description will be made with reference to FIGS. 1 to 9, FIGS. 10(A) to 10(D), and FIGS. 11(A) to 11(C). Note that the drawings used in the following description are all schematic, and the dimensional relationships between the elements shown in the drawings, the ratios of the elements, etc. do not necessarily match the actual ones. Also, the dimensional relationships between the elements and the ratios of the elements do not necessarily match between the plurality of drawings.

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

[0011] The substrate processing apparatus 10 includes a reaction tube storage chamber 206b. Inside the reaction tube storage chamber 206b, there are a cylindrical reaction tube 210 extending in the vertical direction, 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 rectifying unit 214 and nozzles 223 and 224, which will be described later. Also, the gas exhaust unit may include a downstream rectifying unit 215, which will be described later. Among the reaction tube 210, the section for processing the substrate S is called a processing chamber 201.

[0012] The gas supply structure 212 is provided upstream in the gas flow direction of the reaction tube 210. Gas is supplied from the gas supply structure 212 into the reaction tube 210, and the gas is supplied to the substrate S from the horizontal direction. The gas exhaust structure 213 is provided downstream in the gas flow direction of the reaction tube 210, and the gas in the reaction tube 210 is discharged from the gas exhaust structure 213. The gas supply structure 212, the inside of the reaction tube 210, and the gas exhaust structure 213 communicate with each other in the horizontal direction.

[0013] An upstream rectifying unit 214 for rectifying the flow of the 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. Also, a downstream rectifying unit 215 for rectifying the flow of the gas discharged 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 rectifying unit 214, and the downstream rectifying unit 215 have a continuous structure and are formed of a material such as quartz or SiC, for example. These are composed of heat-permeable members that transmit the heat radiated from the heater 211. The heat of the heater 211 heats the substrate S and the gas.

[0015] The gas supply structure 212 has a distribution unit 225 to which a gas supply pipe 251 and a gas supply pipe 261 are connected and which distributes the gas supplied from each gas supply pipe. A plurality of nozzles 223 and 224 are provided on the downstream side of the distribution unit 225. The gas supply pipe 251 and the gas supply pipe 261 supply different types of gas as will be described later. The nozzles 223 and 224 are arranged in a vertical relationship or a side-by-side relationship. In this embodiment, the gas supply pipe 251 and the gas supply pipe 261 are collectively also referred to as the gas supply pipe 221. Each nozzle is also referred to as a gas discharge part.

[0016] The distribution unit 225 is configured such that the gas from the gas supply pipe 251 is supplied to the nozzle 223 and the gas from the gas supply pipe 261 is supplied to the nozzle 224. For example, for each combination of each gas supply pipe and nozzle, a path through which the gas flows is configured. By doing so, the gas supplied from each gas supply pipe does not mix, and thus the generation of particles that may occur due to the mixing of the gas in the distribution unit 225 can be suppressed.

[0017] The upstream rectifying unit 214 has a housing 227 and a partition plate 226. The partition plate 226 extends in the horizontal direction. The horizontal direction referred to here indicates the side wall direction of the housing 227. A plurality of partition plates 226 are arranged in the vertical direction. The partition plate 226 is fixed to the side wall of the housing 227 and is configured such that the gas does not move beyond the partition plate 226 to the adjacent region below or above. By preventing the gas from moving beyond the partition plate 226, the gas flow described later can be surely formed.

[0018] The partition plate 226 extends in the horizontal direction and has a continuous structure without holes. Each partition plate 226 is provided at a position corresponding to each substrate S. The nozzles 223 and 224 are provided between the partition plates 226 and between the partition plates 226 and the housing 227.

[0019] The gas discharged from nozzles 223 and 224 has its gas flow rectified by the partition plate 226 and is supplied to the surface of the substrate S. That is, when viewed from the substrate S, the gas is supplied from the lateral direction of the substrate S. Since the partition plate 226 extends in the horizontal direction and has a continuous structure without holes, the main flow of the gas is suppressed from moving in the vertical direction and is moved in the horizontal direction. Therefore, the pressure loss of the gas reaching each substrate S can be made uniform in the vertical direction.

[0020] The downstream rectifying portion 215 is configured such that, in a state where the substrate S is supported by a substrate support 300 described later, the ceiling is higher than the uppermost substrate S, and the bottom is lower than the lowermost substrate S arranged in the substrate support 300.

[0021] The downstream rectifying portion 215 includes a housing 231 and a partition plate 232. The partition plate 232 extends in the horizontal direction. Here, the horizontal direction refers to the side wall direction of the housing 231. Further, a plurality of partition plates 232 are arranged in the vertical direction. The partition plate 232 is fixed to the side wall of the housing 231 and is configured such that the gas does not move beyond the partition plate 232 to the adjacent region below or above. By preventing such movement, the gas flow described later can be reliably formed. A flange 233 is provided on the side of the housing 231 that contacts the gas exhaust structure 213.

[0022] The partition plate 232 extends horizontally and has a continuous structure without holes. The partition plate 232 is provided at a position corresponding to each substrate S and at a position corresponding to each partition plate 226. It is desirable that the corresponding partition plate 226 and partition plate 232 have the same height. Furthermore, when processing the substrate S, it is desirable to align the height of the substrate S with the heights of the partition plate 226 and partition plate 232. With such a structure, the gas supplied from each nozzle forms a horizontal flow that passes over the partition plate 226, the substrate S, and the partition plate 232 as shown by the arrows in the figure. By configuring the partition plate 232 in such a structure, the pressure loss of the gas discharged from each substrate S can be made uniform. Therefore, the gas flow passing through each substrate S is formed horizontally toward the gas exhaust structure 213 while suppressing the vertical flow.

[0023] By providing the partition plate 226 and the partition plate 232, the pressure loss in the vertical direction can be made uniform upstream and downstream of each substrate S, respectively, so that a horizontal gas flow with the vertical flow suppressed can be reliably formed over the partition plate 226, the substrate S, and the partition plate 232.

[0024] The gas exhaust structure 213 is provided downstream of the downstream-side rectifying section 215. The gas exhaust structure 213 is mainly composed of a housing 241 and a gas exhaust pipe connection section 242. A flange 243 is provided on the side of the housing 241 facing the downstream-side rectifying section 215. Since the gas exhaust structure 213 is made of metal and the downstream-side rectifying section 215 is made of quartz, the flange 233 and the flange 243 are fixed with screws or the like via a buffer material such as an O-ring. It is desirable that the flange 243 be arranged outside the heater 211 so as to suppress the influence of the heater 211 on the O-ring.

[0025] The gas exhaust structure 213 communicates with the space of the downstream rectifying section 215. The housing 231 and the housing 241 have a continuous height structure. The ceiling part of the housing 231 is configured to have the same height as the ceiling part of the housing 241, and the bottom part of the housing 231 is configured to have the same height as the bottom part of the housing 241. An exhaust hole 244 is formed on the downstream side of the housing 241 and on the lower side or in the horizontal direction. The gas exhaust structure 213 is a lateral exhaust structure provided in the lateral direction of the reaction tube 210 and exhausting gas from the lateral direction of the substrate S.

[0026] The gas that has passed through the downstream rectifying section 215 is exhausted from the exhaust hole 244. At this time, since the gas exhaust structure 213 has no configuration like a partition plate, a gas flow including the vertical direction is formed toward the exhaust hole 244.

[0027] The transfer chamber 217 is installed below the reaction tube 210 via a manifold 216. In the transfer chamber 217, the substrate S is placed (mounted) on a substrate support tool (hereinafter, may be simply referred to as a boat) 300 by a vacuum transfer robot via a substrate transfer inlet, or the substrate S is taken out from the substrate support tool 300 by the vacuum transfer robot.

[0028] Inside the transfer chamber 217, it is possible to store a substrate support tool 300, a partition plate support part 310, and a vertical drive mechanism part 400 that constitutes a first drive part for driving the substrate support tool 300 and the partition plate support part 310 (collectively referred to as a substrate holder) in the vertical direction and the rotation direction. In FIG. 1, the substrate support tool 300 is lifted by the vertical drive mechanism part 400 and shown in a state of being stored in the reaction tube 210.

[0029] The vertical drive mechanism part 400 that constitutes the first drive part includes, as a drive source, a vertical drive motor 410, a rotation drive motor 430, and a boat vertical mechanism 420 having a linear actuator as a substrate support tool lifting mechanism for driving the substrate support tool 300 in the vertical direction.

[0030] The up-and-down drive motor 410 for the partition plate support part lifting mechanism drives the ball screw 411 to rotate, thereby moving the nut 412 screwed onto the ball screw 411 up and down along the ball screw 411. As a result, the partition plate support part 310 and the substrate support tool 300 together with the base plate 402 fixing the nut 412 are driven in the vertical direction between the reaction tube 210 and the transfer chamber 217. The base plate 402 is also fixed to the ball guide 415 engaged with the guide shaft 414, and is configured to be able to move smoothly in the vertical direction along the guide shaft 414. The upper and lower ends of the ball screw 411 and the guide shaft 414 are fixed to the fixed plates 413 and 416 respectively.

[0031] The boat vertical movement mechanism 420 including the rotation drive motor 430 and the linear actuator constitutes a second drive part, and is fixed to the base flange 401 as a lid body supported by the side plate 403 on the base plate 402.

[0032] The rotation drive motor 430 drives the rotation transmission belt 432 engaged with the tooth part 431 attached to the tip part, and drives the support tool 440 engaged with the rotation transmission belt 432 to rotate. The support tool 440 supports the partition plate support part 310 by the base part 311, and rotates the partition plate support part 310 and the substrate support tool 300 by being driven by the rotation drive motor 430 via the rotation transmission belt 432.

[0033] The boat vertical movement mechanism 420 including the linear actuator drives the shaft 421 in the vertical direction. A plate 422 is attached to the tip part of the shaft 421. The plate 422 is connected to the support part 441 fixed to the base part 301 of the substrate support tool 300 via the bearing 423. When the rotation drive motor 430 rotates the partition plate support part 310, the substrate support tool 300 can rotate together with the partition plate support part 310 because the support part 441 is connected to the plate 422 via the bearing 423.

[0034] On the one hand, the support part 441 is supported by the support tool 440 via the linear guide bearing 442. With such a configuration, when the shaft 421 is driven in the vertical direction by the boat lifting mechanism 420 equipped with the linear actuator, the support part 441 fixed to the substrate support tool 300 can be driven relatively in the vertical direction with respect to the support tool 440 fixed to the partition plate support part 310.

[0035] Between the support tool 440 fixed to the partition plate support part 310 and the support part 441 fixed to the substrate support tool 300, they are connected by a vacuum bellows 443.

[0036] On the upper surface of the base flange 401 as the lid body, an O-ring 446 for vacuum sealing is installed. As shown in FIG. 1, by driving with the vertical drive motor 410 and raising it to the position where the upper surface of the base flange 401 is pressed against the transfer chamber 217, the inside of the reaction tube 210 can be kept airtight.

[0037] Next, the details of the substrate support part will be described with reference to FIGS. 1 and 2. The substrate support part is composed of at least a substrate support tool 300 that supports the substrate S, and is stored in the reaction tube 210. The substrate S is arranged directly below the inner wall of the top plate of the reaction tube 210. Also, the substrate support part transfers the substrate S by a vacuum transfer robot through a substrate transfer inlet (not shown) inside the transfer chamber 217, or conveys the transferred substrate S into the reaction tube 210 to perform a process of forming a thin film on the surface of the substrate S. The substrate transfer inlet is provided, for example, on the side wall of the transfer chamber 217. Note that the partition plate support part 310 may be considered together with the substrate support part.

[0038] In the partition plate support part 310, a plurality of disk-shaped partition plates 314 are fixed at a predetermined pitch to the support columns 313 supported between the base part 311 and the top plate 312. The substrate support tool 300 has a configuration in which a plurality of support rods 315 are supported by the base part 311, and a plurality of substrates S are supported at a predetermined interval by the plurality of support rods 315.

[0039] On the substrate support 300, a plurality of substrates S are placed at a predetermined interval by a plurality of support rods 315 supported by a base 311. Between the plurality of substrates S supported by the support rods 315, there is a disk-shaped partition plate 314 that is fixedly supported (supported) at a predetermined interval by a support column 313 supported by a partition plate support portion 310. Here, the partition plate 314 is disposed directly below the substrate S and is disposed on either or both of the upper and lower portions of the substrate S. The partition plate 314 blocks the space of each substrate S.

[0040] The predetermined interval between the plurality of substrates S placed on the substrate support 300 is the same as the vertical interval between the upper and lower partition plates 314 fixed to the partition plate support portion 310. Further, the diameter of the partition plate 314 is formed larger than the diameter of the substrate S.

[0041] The substrate support 300 supports a plurality of, for example, five substrates S in multiple stages in the vertical direction (perpendicular direction) with a plurality of support rods 315. The base 311, the partition plate 314, and the plurality of support rods 315 are formed of a material such as quartz or SiC, for example. Here, an example in which five substrates S are supported by the substrate support 300 is shown, but the present invention is not limited thereto. For example, the substrate support 300 may be configured to support about 5 to 50 substrates S. Note that the partition plate 314 of the partition plate support portion 310 is also referred to as a separator.

[0042] The partition plate support portion 310 and the substrate support 300 are driven 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 by a vertical drive mechanism portion 400.

[0043] Subsequently, the details of the gas supply system will be described with reference to FIGS. 3(A) to 3(C). As shown in FIG. 3(A), the gas supply pipe 251 is provided with a first gas source 252, a mass flow controller (flow control unit) MFC 253 as a flow rate controller, a valve 275 as an on-off valve, a tank 259 as a storage unit for storing gas, and a valve 254 as an on-off valve in order from the upstream direction.

[0044] 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 raw material gas, i.e., one of the process gases. Here, the first gas is a gas in which at least two silicon atoms (Si) are bonded, for example, a gas containing Si and chlorine (Cl), and is a raw material gas containing an Si-Si bond such as disilicon hexachloride (Si2Cl6, hexachlorodisilane, abbreviation: HCDS) gas described in FIG. 4(A). As shown in FIG. 4(A), the HCDS gas contains Si and chloro groups (chlorides) in its chemical formula (per molecule).

[0045] This Si-Si bond has energy to the extent that it decomposes by colliding with the wall that constitutes the recess of the substrate S described later in the reaction tube 210. Here, decomposition means that the Si-Si bond is cleaved. That is, the Si-Si bond is cleaved by collision with the wall.

[0046] The first gas supply system 250 (also referred to as a silicon-containing gas supply system) is mainly constituted by the gas supply pipe 251, the MFC 253, the valve 275, the tank 259, and the valve 254.

[0047] Among the gas supply pipes 251, a gas supply pipe 255 is connected between the valve 275 and the tank 259. The gas supply pipe 255 is provided with an inert gas source 256, an MFC 257, and a valve 258 which is an on-off valve, in this order from the upstream direction. An inert gas, for example, nitrogen (N2) gas is supplied from the inert gas source 256.

[0048] The first inert gas supply system is mainly constituted by the gas supply pipe 255, the MFC 257, and the valve 258. The inert gas supplied from the inert gas source 256 acts as a purge gas for purging the gas remaining in the reaction tube 210 in the substrate processing step. The first inert gas supply system may be added to the first gas supply system 250.

[0049] Although HCDS gas has been described as an example of the first gas here, it is not limited thereto as long as it contains silicon and has Si-Si bonds. For example, 1,1,2,2-tetrachloro-1,2-dimethyldisilane ((CH3)2Si2Cl4, abbreviation: TCDMDS) or 1,2-dichloro-1,1,2,2-tetramethyldisilane ((CH3)4Si2Cl2, abbreviation: DCTMDS) may be used. As shown in FIG. 4(B), TCDMDS has an Si-Si bond and further contains a chloro group and an alkylene group. Also, as shown in FIG. 4(C), DCTMDS has an Si-Si bond and further contains a chloro group and an alkylene group.

[0050] As shown in FIG. 3(B), the gas supply pipe 261 is provided with, in order from the upstream direction, a second gas source 262, an MFC 263 which is a flow rate controller (flow rate control unit), a valve 276 which is an on-off valve, a tank 269 which is a storage unit for storing gas, and a valve 264 which is an on-off valve.

[0051] The second gas source 262 is a source of a second gas containing a second element (hereinafter, also referred to as "second element-containing gas"). The second gas is a gas different from the first gas and is one of the process gases. Note that the second gas may be considered as a reaction gas or a reforming gas that reacts with a precursor of the first gas which is a raw material gas.

[0052] Here, the second gas contains a second element different from the first gas. The second element is, for example, any one of oxygen (O), nitrogen (N), and carbon (C). In this embodiment, the second gas is, for example, a gas containing hydrogen and nitrogen, and is a hydrogen nitride-based gas containing an N-H bond such as ammonia (NH3), diazene (N2H2) gas, hydrazine (N2H4) gas, N3H8 gas.

[0053] The second gas supply system 260 is mainly constituted by the gas supply pipe 261, the MFC 263, the valve 276, the tank 269, and the valve 264.

[0054] Among the gas supply pipes 261, a gas supply pipe 265 is connected between the valve 276 and the tank 269. The gas supply pipe 265 is provided with an inert gas source 266, an MFC 267, and a valve 268 which is an on-off valve, in this order from the upstream direction. An inert gas, for example, nitrogen (N2) gas is supplied from the inert gas source 266.

[0055] Primarily, the gas supply pipe 265, the MFC 267, and the valve 268 constitute a second inert gas supply system. The inert gas supplied from the inert gas source 266 acts as a purge gas for purging the gas remaining in the reaction tube 210 in the substrate processing step. The second inert gas supply system may be added to the second gas supply system 260.

[0056] As shown in FIG. 3(C), the gas supply pipe 271 is provided with a third gas source 272, an MFC 273 which is a flow controller (flow control unit), and a valve 274 which is an on-off valve, in this order from the upstream direction. The gas supply pipe 271 is connected to the transfer chamber 217. When making the transfer chamber 217 an inert gas atmosphere or making the transfer chamber 217 in a vacuum state, an inert gas is supplied.

[0057] The third gas source 272 is an inert gas source. Primarily, the gas supply pipe 271, the MFC 273, and the valve 274 constitute a third gas supply system 270. The third gas supply system is also called a transfer chamber supply system.

[0058] Subsequently, the exhaust system will be described with reference to FIGS. 5(A) and 5(B). An exhaust system 280 for exhausting the atmosphere of 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 connection portion 242.

[0059] As shown in Fig. 5(A), a vacuum pump 284 as a vacuum exhaust device is connected to an exhaust pipe 281 via a valve 282 as an on-off valve and an APC (Auto Pressure Controller) valve 283 as a pressure regulator (pressure regulating unit), and is configured to be able to perform vacuum exhaust so that the pressure in the reaction tube 210 becomes a predetermined pressure (degree of vacuum). 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 process chamber exhaust system. Note that the pump 284 may be included in the exhaust system 280.

[0060] An exhaust system 290 for exhausting the atmosphere of the transfer chamber 217 is connected to the transfer chamber 217 and has an exhaust pipe 291 communicating with the inside thereof.

[0061] As shown in Fig. 5(B), a vacuum pump 294 as a vacuum exhaust device is connected to an exhaust pipe 291 via a valve 292 as an on-off valve and an APC valve 293, and is configured to be able to perform vacuum exhaust so that the pressure in the transfer chamber 217 becomes a predetermined pressure (degree of vacuum). 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. Note that the pump 294 may be included in the exhaust system 290.

[0062] Subsequently, a controller, which is a control unit (control means), will be described with reference to Fig. 6. The substrate processing apparatus 10 has a controller 600 that controls the operations of each part of the substrate processing apparatus 10.

[0063] An outline of the controller 600 is shown in Fig. 6. 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. Transmission and reception of data within the substrate processing apparatus 10 are performed according to an instruction from a transmission / reception instruction unit 606, which is also a function of the CPU 601.

[0064] The controller 600 is provided with a network transceiver 683 connected to the upper device 670 via a network. The network transceiver 683 can receive information regarding the processing history and processing schedule of the substrate S stored in the pod from the upper device 670 and the like.

[0065] The storage device 603 is composed of, for example, a flash memory, an HDD (Hard Disk Drive), or the like. In the storage device 603, a control program for controlling the operation of the substrate processing apparatus 10, a process recipe describing the procedures and conditions of substrate processing, and the like are stored in a readable manner.

[0066] Note that the process recipe is a combination of procedures in the substrate processing steps described later that cause the controller 600 to execute and obtain a predetermined result, and functions as a program. Hereinafter, this process recipe, control program, etc. are collectively referred to simply as a program. Note that when the term "program" is used in this specification, it may include only the process recipe alone, only the control program alone, or both. Also, the RAM 602 is configured as a memory area (work area) that temporarily holds programs, data, etc. read by the CPU 601.

[0067] The I / O port 604 is connected to each component of the substrate processing apparatus 10.

[0068] The CPU 601 is configured to read and execute the control program from the storage device 603 and to read the process recipe from the storage device 603 in response to the input of an operation command from the input / output device 681 and the like. Then, the CPU 601 is configured to be able to control the substrate processing apparatus 10 in accordance with the content of the read process recipe.

[0069] The CPU 601 has a transmission / reception instruction unit 606. The controller 600 can be configured by installing a program in a computer using an external storage device (for example, 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) 682 that stores the above-described program. Note that the means for supplying a program to the computer is not limited to supplying via the external storage device 682. For example, communication means such as the Internet or a dedicated line may be used to supply the program without passing through the external storage device 682. Note that the storage device 603 and the external storage device 682 are configured as computer-readable recording media. Hereinafter, these are collectively referred to simply as recording media. Note that in this specification, when the term recording medium is used, it may include only the storage device 603 alone, only the external storage device 682 alone, or both of them.

[0070] Next, as one step of 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 FIGS. 7 to 9 and FIGS. 10(A) to 10(D). Note that in the following description, the operations of the respective units constituting the substrate processing apparatus 10 are controlled by the controller 600.

[0071] Here, a film formation process of forming a film in a concave portion such as a trench or a hole of the substrate S using a first gas and a second gas will be described. On the surface of the concave portion of the substrate S, adsorption sites are formed in advance by supplying a reaction gas such as NH3 gas. An adsorption site refers to a region on the surface of the substrate S where molecules or atoms can be adsorbed. The NH groups present on the surface of the substrate S in FIG. 10(A) have a function as adsorption sites for molecules or atoms.

[0072] (S102) Describe the transfer chamber pressure adjustment step S102. Here, the pressure in the transfer chamber 217 is set to the same level as that of a vacuum transfer chamber (not shown) adjacent to the transfer chamber 217. Specifically, operate the exhaust system 290 to exhaust the atmosphere in the transfer chamber 217 so that the atmosphere in the transfer chamber 217 reaches the vacuum level.

[0073] (S104) Subsequently, describe the substrate loading step S104. When the transfer chamber 217 reaches the vacuum level, start transporting the substrate S. When the substrate S arrives at the vacuum transfer chamber, release the gate valve, and the vacuum transfer robot transports the substrate S into the transfer chamber 217.

[0074] At this time, the substrate support 300 waits in the transfer chamber 217, and the substrate S is transferred to the substrate support 300. When a predetermined number of substrates S are transferred to the substrate support 300, retract the vacuum transfer robot and raise the substrate support 300 by the vertical drive mechanism 400 to move the substrate S into the reaction tube 210.

[0075] When moving into the reaction tube 210, the substrate S is positioned so that the surface of the substrate S aligns with the heights of the partition plates 226 and 232.

[0076] (S106) Subsequently, describe the heating step S106. After loading the substrate S into the reaction tube 210, control the inside of the reaction tube 210 to reach a predetermined pressure and control the surface temperature of the substrate S to reach a predetermined temperature. The temperature of the heater 211 is controlled so that the temperature of the substrate S is, for example, 100°C or higher and 1500°C or lower, preferably 200°C or higher and 1000°C or lower, and more preferably 400°C or higher and 800°C or lower. Also, the pressure inside the reaction tube 210 can be considered to be, for example, from 5 Pa to 100 kPa.

[0077] (S108) Next, the film treatment step S108 will be described. After the heating step S106, the film treatment step of S108 is performed. In the film treatment step S108, according to the process recipe, a first gas supply step of supplying a first gas described later to the concave portion of the substrate S having adsorption sites on the surface to the substrate S, and a second gas supply step of supplying a second gas to the substrate S are repeatedly performed a predetermined number of times to form a predetermined film on the substrate S having concave portions on the surface.

[0078] The supplied gas forms a gas flow in the upstream-side rectifying portion 214, the space above the substrate S, and the downstream-side rectifying portion 215 for each substrate S. At this time, since the gas is supplied to the substrate S in a state where there is no pressure loss on each substrate S, uniform processing can be performed among the substrates S.

[0079] Note that the upstream-side rectifying portion 214, the downstream-side rectifying portion 215, and the plurality of substrates S may be configured to correspond to each other. In that case, it is advantageous in terms of reducing the number of parts. However, the pressure between the plurality of substrates S, the gas hits the side surface of the substrate and turbulent flow occurs, and the gas supply situation changes between the other substrates arranged vertically, resulting in variations in processing between the substrates S. Especially when turbulent flow occurs, there is a risk of gas stagnation in front of the substrate S, so gas decomposition progresses in front of the substrate S, and as a result, it accumulates on the edge side of the substrate S. Therefore, the uniformity in the in-plane processing of the substrate becomes low.

[0080] As a result, variations may occur in the film treatment. Therefore, the point of providing the upstream-side rectifying portion 214 and the downstream-side rectifying portion 215 corresponding to one substrate S as in the present embodiment is advantageous in terms of reducing variations in processing between the substrates S.

[0081] <First Gas Supply Step> First, the step of supplying a first gas to the concave portion of the substrate S having adsorption sites on the surface will be described. In the first gas supply step, a first gas flash supply (step A), a purge (step B), a first gas continuous supply (step C), and a purge (step D) described later are combined and performed.

[0082] Here, flash supply means supplying a large amount of gas into the reaction tube 210 at once. Specifically, in flash supply, gas is stored in advance in a tank provided in the gas supply pipe, and when supplying the gas, by opening a valve provided on the downstream side of the tank between the tank and the nozzle, it is supplied at a faster speed compared to the continuous supply described later.

[0083] [First Gas Flash Supply (Step A)] In this step, valve 254 is opened, and the first gas is supplied from tank 259 in which the first gas has been stored in advance into gas supply pipe 251. After a predetermined time has elapsed, for example, after a time within the range of 0.1 to 5 seconds, for example, after 0.3 seconds, valve 254 is closed to stop the supply of the first gas into gas supply pipe 251. The first gas is supplied in a large amount at once into reaction tube 210 from gas supply structure 212 through upstream rectifying section 214. Then, it is exhausted through the space above substrate S, downstream rectifying section 215, gas exhaust structure 213, and exhaust pipe 281. Here, during the supply of the first gas into processing chamber 201, valve 275 may be either open or closed. Also, valve 258 may be opened, and an inert gas such as N2 gas may be flowed into gas supply pipe 251 through gas supply pipe 255. Further, in order to prevent the intrusion of the first gas into gas supply pipe 261, valves 268 and 264 may be opened, and an inert gas may be flowed into gas supply pipe 261.

[0084] At this time, APC valve 283 is adjusted so that the pressure inside reaction tube 210 is, for example, within the range of 1 to 3990 Pa. In the following, the temperature of heater 211 is set such that the temperature of substrate S is, for example, within the range of 100 to 1500 °C and is heated between 400 °C and 800 °C.

[0085] At this time, through gas supply structure 212 communicating with the inside of reaction tube 210, the first gas is supplied in a large amount at once in the horizontal direction with respect to substrate S from the side of substrate S. The flow rate of the first gas at this time is, for example, within the range of 0.5 to 100 m / s, preferably 1 to 50 m / s, and more preferably 2 to 50 m / s.

[0086] As the first gas, a gas in which at least two Si atoms are bonded can be used. For example, Si2Cl6 gas (hereinafter referred to as HCDS gas), which is a gas containing Si and Cl, can be used.

[0087] When, for example, HCDS gas is used as the first gas, since the Si bonds have a binding energy such that they can be broken by collisions with the walls, the impact of colliding with the wall 700 forming the recess breaks the bonds between the Si bonds, and they are decomposed into the precursors SiCl2 and SiCl4. Then, SiCl2 with a high adsorption degree adsorbs to the upper part of the recess, and SiCl4 with a lower adsorption degree than SiCl2 moves to the lower part of the recess. Therefore, SiCl2 reacts with the NH groups in the upper part of the recess, and SiCl4 reacts with the NH groups in the lower part of the recess to form a SiN layer. Also, reaction by-products such as hydrogen chloride (HCl) are generated at this time. Here, the adsorption degree refers to the degree of ease of adsorption.

[0088] HCl, which is a reaction by-product, adsorbs to the NH groups, so it becomes a factor inhibiting the bonding between Si and the NH groups. Also, the amount of HCl generated when SiCl2 and SiCl4 adsorb to the NH groups is larger for SiCl4 than for SiCl2. Also, due to the structure in which the gas is supplied by side flow, it is likely to be depleted in the lower part of the recess. That is, SiCl2 is likely to contribute to film formation in the upper part of the recess, and SiCl4 is likely to contribute to film formation in the lower part of the recess. For this reason, there is a concern that the film thickness will be different between the upper and lower parts of the recess, the film thickness uniformity within the recess will deteriorate, and the step coverage will deteriorate.

[0089] Also, although the HCl generated in the upper part of the recess is discharged outside the recess, the HCl will remain in the lower part of the recess. For this reason, there is a concern that voids will be formed within the recess and the step coverage will deteriorate.

[0090] Therefore, in step A, the first gas is supplied at a rate faster than the adsorption rate at which the precursor of the first gas adsorbs to the adsorption sites (e.g., NH groups) on the surface of the substrate S. As a result, the first gas collides with the wall 700 forming the concave portion of the substrate S and is decomposed into a first component and a second component with an adsorption degree lower than that of the first component, generating a predetermined amount of the first component within the concave portion 700. For this reason, the precursor of the decomposed first component adheres to the inner wall of the wall forming the concave portion. That is, in this step, the first component of the first gas can be adsorbed by being greatly exposed to the adsorption sites in the concave portion of the substrate S in a short time.

[0091] Here, the adsorption rate is the rate at which the precursor of the first gas can adsorb to the adsorption sites of the substrate S, and here, it is the rate at which the precursor of the first component of the first gas described later adsorbs to the adsorption sites. Also, a rate faster than the adsorption rate at which the precursor of the first gas adsorbs to the adsorption sites on the surface of the substrate S means that the precursor of the first gas is supplied and adsorbed to the lower part of the concave portion before it adsorbs to the adsorption sites at the upper part of the concave portion of the substrate S.

[0092] For example, when using HCDS gas as the first gas, the undissociated HCDS gas is supplied into the processing chamber 201 from the side of the substrate S. The supply rate of the first gas at this time is set to be faster than the adsorption rate at which the precursor of the first gas adsorbs to the adsorption sites on the side surface of the concave portion. Here, as shown in FIG. 9, the first gas is made to collide with the wall 700 forming the concave portion, and by this collision, the Si-Si bond of Si2Cl6, which is HCDS gas, is broken. After the breakage, the HCDS gas is decomposed into SiCl2 as the first component, which is the precursor, and SiCl4 as the second component, which is the precursor. Since SiCl2 and SiCl4 are also in a state where the film is being formed, they are also called intermediates. The adsorption degree of the decomposed SiCl2 is higher than that of the decomposed SiCl4. Therefore, the probability that SiCl2 and SiCl4 adsorb to the NH group, which is the adsorption site, is higher for SiCl2 than for SiCl4. In other words, the film formation rate is better for SiCl2 than for SiCl4. For this reason, as shown in FIG. 10(A), in this step, SiCl2, which has a higher adsorption degree than SiCl4, is adsorbed to the NH group in the concave portion, and HCl is desorbed or remains.

[0093] Here, since a large amount of SiCl2 binds and is consumed at the upper part of the concave portion, there is a concern that a relatively small amount of SiCl2 is supplied to the lower part of the concave portion. In contrast, in this embodiment, since the first gas is supplied at a rate faster than the adsorption rate of the first component, SiCl2 can be supplied to the lower part of the concave portion before a large amount of SiCl2 is consumed above the concave portion. Therefore, an Si-containing layer with improved step coverage performance can be formed.

[0094] [Purge (Step B)] In this step, a purge gas is supplied to the concave portion of the substrate S having adsorption sites on its surface. That is, after the supply of the first gas flash in Step A, the first component and the second component that were not adsorbed on the adsorption sites, and reaction by-products such as HCl that are generated by surface reaction and re-adsorbed on the surface of the substrate S are desorbed and removed from the inside of the reaction tube 210.

[0095] Specifically, with the valve 254 open, the valve 275 is closed, the valves 258, 268, 264 are opened, and an inert gas as a purge gas is supplied into the gas supply pipes 251, 261 through the gas supply pipes 255, 265. At the same time, the valves 282, 283 of the exhaust pipe 281 are kept open, and the inside of the reaction tube 210 is evacuated by the vacuum pump 284. Thereby, the reaction between the first gas and the second gas in the gas phase existing in the reaction tube 210 can be suppressed. For example, as shown in FIG. 10(B), HCl, which is a reaction by-product adsorbed on the lower part of the concave portion of the substrate S, is desorbed and discharged from the inside of the reaction tube 210.

[0096] In particular, at the lower part of the recess, although as described above, a large amount of SiCl2 can be supplied, a large amount of SiCl4 is also supplied in the same way. The adsorption degree of SiCl2 is higher than that of SiCl4, and at the upper part of the recess, more SiCl2 binds than SiCl4. Therefore, more HCl is generated at the lower part of the recess than at the upper part. The generated HCl enters between the adsorption site and SiCl4 or SiCl2, causing adsorption inhibition. Therefore, in order to further improve the step coverage performance, it is desirable to exclude HCl.

[0097] Therefore, in this step, a purge gas is supplied to the recess to desorb the HCl generated in the recess, particularly at the lower part of the recess, to vacate the adsorption site, so that the components of the first gas supplied in the next step C can be adsorbed. Note that the desorbed HCl is discharged from the recess and exhausted from the exhaust pipe 281.

[0098] [Continuous supply of the first gas (step C)] In this step, the gas is supplied at a rate slower than the supply rate of the first gas in step A. For example, the first gas is supplied to the recess of the substrate S at a rate slower than the adsorption rate of the precursor.

[0099] Specifically, with the valve 254 open, the valve 275 is opened to flow the first gas into the gas supply pipe 251. The first gas is flow-rate adjusted by the MFC253 and supplied into the reaction tube 210 from the gas supply structure 212 through the upstream rectifying section 214. Then, it is exhausted through the space above the substrate S, the downstream rectifying section 215, the gas exhaust structure 213, and the exhaust pipe 281. Here, while the first gas is being supplied into the processing chamber 201, the valve 258 may be opened to flow an inert gas such as N2 gas into the gas supply pipe 251 through the gas supply pipe 255. Also, in order to prevent the intrusion of the first gas into the gas supply pipe 261, the valves 268 and 264 may be opened to flow an inert gas into the gas supply pipe 261.

[0100] At this time, the supply flow rate of the first gas controlled by the MFC253 is, for example, set to a flow rate within the range of 0.1 to 20 slm. The time for supplying the first gas to the substrate S is, for example, set to a time within the range of 0.1 to 1000 seconds. The flow velocity of the first gas is, for example, set to a flow velocity within the range of 0.1 to 100 m / s, preferably 0.5 to 50 m / s, and more preferably 1 to 20 m / s.

[0101] In this step, a gas is supplied to the side surface of the recess of the substrate S provided with adsorption sites at a speed slower than the supply speed in step A. Here, since many adsorption sites are filled, even at a slow speed, it is possible to sufficiently bond to the adsorption sites. By supplying the gas at a slow speed, the consumption amount of the first gas can be suppressed.

[0102] Also, in step A, when a sufficient amount of SiCl2 has been supplied to the lower part of the recess, it is sufficient to supply SiCl2 to the empty adsorption sites centered on the upper part of the recess. Therefore, the gas may be supplied at a speed slower than that in step A, for example, at a speed slower than the bonding speed of SiCl2. By doing so, the consumption amount of the first gas can be suppressed.

[0103] In addition, if it is determined that there are many empty adsorption sites in the lower part of the recess after step A, the first gas may be supplied at a speed faster than the bonding speed of SiCl2 even if it is slower than the gas supply speed in step A. In this case, similar to step A, a large amount of SiCl2 can also be supplied to the lower part of the recess. Therefore, even when there are many empty adsorption sites in the lower part of the recess, the step coverage performance can be improved.

[0104] As a result, for example, as shown in FIG. 10(C), SiCl2 after the decomposition of the HCDS gas can be adsorbed on the adsorption sites formed by desorbing reaction by-products such as HCl in FIG. 10(B) and the adsorption sites that were also unbonded in step A. At this time, since the number of adsorption sites is smaller than before step A, the first gas only needs to be supplied in an amount corresponding to the adsorption sites. Therefore, a smaller amount may be supplied than in step A.

[0105] [Purge (Step D)] In this step, after Step C, a purge gas is supplied to the recess of the substrate S having adsorption sites on its surface. That is, the first gas is supplied again to the adsorption sites formed by removing the reaction by-products, and purging is performed. Since this step is the same as Step B described above, it may be replaced with Step B.

[0106] After a predetermined time has elapsed since the start of the continuous supply of the first gas, with the valve 254 open, the valve 275 is closed to stop the supply of the first gas. At this time, the valves 258, 268, and 264 are opened, and an inert gas as a purge gas is supplied into the gas supply pipes 251 and 261 through the gas supply pipes 255 and 265. At the same time, the valves 282 and 283 of the exhaust pipe 281 are kept open, and the inside of the reaction tube 210 is evacuated by the vacuum pump 284. Thereby, the reaction in the gas phase existing in the reaction tube 210 can be suppressed. That is, HCl and residual gas, which are reaction by-products adsorbed on the lower part of the recess of the substrate S, are discharged from the inside of the reaction tube 210.

[0107] The above Steps A, B, C, and D are combined as shown in Fig. 8(A) to supply the first gas to the recess of the substrate S having adsorption sites on its surface.

[0108] Specifically, as the first gas supply process, a first gas flash supply (Step A) and a purge gas supply (Step B) are performed in this order in the first step, a first gas flash supply (Step A), a purge gas supply (Step B), a first gas continuous supply (Step C), and a purge gas supply (Step D) are performed in this order in the second step, a first gas flash supply (Step A) and a purge gas supply (Step B) are performed, and then, a first gas continuous supply (Step C) and a purge gas supply (Step D) are repeatedly performed a predetermined number of times (n times) in the nth step (n is an integer of 1 or more).

[0109] In this specification, for convenience, the film formation sequence in this aspect may sometimes be shown as follows. The same notation is used in the descriptions of other aspects and the like below. First step: Step A → Step B Second step: Step A → Step B → Step C → Step D nth step: Step A → Step B → (Step C → Step D) × (n - 1)

[0110] That is, as the first gas supply process, the above-described first step, second step, and nth step are performed. As described above, as the number of steps increases, by increasing the number of times of Step C and Step D, a precursor of the first gas with a good film formation rate and a small amount of reaction by-products can be adsorbed onto the vacant adsorption sites in the concave portion.

[0111] By performing the above-described first step to the nth step, a first gas-containing film, which is a raw material gas-containing film, is formed in the concave portion of the substrate S. That is, by performing the first step to the nth step and repeating this step, the step coverage can be improved.

[0112] Here, in the above-described nth step, when repeating Step C and Step D, the time of D when the number of repetitions is small is made longer than the time of D when the number of repetitions increases. In other words, when repeating Step C and Step D, as the number of repetitions increases, the time of Step D is shortened. This is because as the number of repetitions increases, the adsorption sites on the surface of the substrate S decrease. Thereby, gas can be supplied in an appropriate amount to save waste and improve the throughput.

[0113] In addition, in the above-described n-th step, when repeating step C and step D, the supply amount per unit time of the inert gas in D when the number of repetitions is small may be made larger than the supply amount per unit time of the inert gas in D when the number of repetitions increases. In other words, when repeating step C and step D, the supply amount per unit time of the inert gas in step D may be decreased as the number of repetitions increases.

[0114] Further, in the above-described n-th step, when repeating step C and step D, the time of step C when the number of repetitions is small is made longer than the time of step C when the number of repetitions increases. In other words, when repeating step C and step D, the time of step C is shortened as the number of repetitions increases. This is because, similar to the time of step D described above, as the number of repetitions increases, the adsorption sites on the surface of the substrate S decrease. Thereby, gas can be supplied in an appropriate amount to save waste and improve throughput.

[0115] In addition, in the above-described n-th step, when repeating step C and step D, the supply amount per unit time of the first gas in step C when the number of repetitions is small may be made larger than the supply amount per unit time of the first gas in step C when the number of repetitions increases. In other words, when repeating step C and step D, the supply amount per unit time of the first gas in step C may be decreased as the number of repetitions increases.

[0116] Also, the time of the purge step (step B) performed immediately after the above-described step A is made longer than the time of the purge step (step D) performed immediately after the above-described step C. This is because the generation of reaction by-products is suppressed because the adsorption sites on the surface of the substrate S decrease more immediately after step C than immediately after step A. Thereby, while suppressing the generation of reaction by-products, gas can be supplied in an appropriate amount to save waste and improve throughput.

[0117] In addition, the supply amount of the inert gas per unit time in the purge step (step B) performed immediately after the above-described step A may be made larger than the supply amount of the inert gas per unit time in the purge step (step D) performed immediately after the above-described step C.

[0118] <Second Gas Supply Step> Next, a step of supplying a second gas to the concave portions on the substrate surface will be described. In the second gas supply step, as shown in FIG. 8(B), a second gas flash step (step E) and a purge (step F) described later are performed.

[0119] [Second Gas Flash Supply (Step E)] In this step, the valve 264 is opened, and the second gas is supplied from the tank 269 in which the second gas has been stored in advance into the gas supply pipe 261. After a predetermined time has elapsed, for example, after a time within the range of 0.1 to 1000 seconds, for example, after 0.3 seconds, the valve 264 is closed to stop the supply of the second gas into the gas supply pipe 251. The second gas is supplied from the gas supply structure 212 into the reaction tube 210 via the upstream rectifying portion 214. Then, it is exhausted through the space above the substrate S, the downstream rectifying portion 215, the gas exhaust structure 213, and the exhaust pipe 281. Here, while the second gas is being supplied into the processing chamber 201, the valve 276 may be either open or closed. Further, the valve 268 may be opened, and an inert gas such as N2 gas may be flowed into the gas supply pipe 261 via the gas supply pipe 265. Further, in order to prevent the second gas from entering the gas supply pipe 251, the valves 258 and 254 may be opened, and an inert gas may be flowed into the gas supply pipe 251.

[0120] At this time, the second gas is supplied in a large amount at once in the horizontal direction with respect to the substrate S from the side of the substrate S through the gas supply structure 212 communicating with the inside of the reaction tube 210. The flow rate of the second gas at this time is, for example, within the range of 0.1 to 20 m / sec, preferably 0.1 to 10 m / sec, and more preferably 0.1 to 5 m / sec.

[0121] As the second gas, a gas different from the first gas and reactive with the precursor of the first gas can be used, for example, NH3 gas which is an N-containing gas. That is, the second gas is supplied to the surface of the substrate S from the side of the substrate S. Then, the second gas is supplied into the recess, forms an adsorption site, reacts with the precursor attached to the wall 700 constituting the recess, and a desired film is formed on the substrate S including within the recess. Specifically, as shown in FIG. 10(D), the NH3 gas supplied into the recess is adsorbed on the surface of the substrate S, reacts with SiCl2 adsorbed in the recess, forms an NH group, and generates reaction by-products such as ammonium chloride (NH4Cl) and HCl.

[0122] Here, when NH3 gas is used as the second gas, when the HCDS gas reacts with the NH3 gas, an NH2 bond is generated on the film. If HCDS and NH2 to be supplied next react, Cl and hydrogen chloride (HCl) will be generated. If this Cl and HCl stay between SiCl2 and the inner wall of the recess, Cl and HCl will inhibit the adhesion of SiCl2 to the inner wall of the recess. Therefore, the temperature is set to a temperature at which by-products such as NH2 generated in the recess of the substrate S are desorbed and the decomposition of HCDS, which is the first gas, is not promoted. Also, NH3 gas is supplied from the side of the substrate S for a time during which HCDS is not decomposed and SiCl2 is not generated.

[0123] [Purge, (Step F)] In this step, after step E, a purge gas is supplied to the recess of the substrate S having adsorption sites on its surface. That is, after the second gas is flash-supplied, the second gas that was not adsorbed on the adsorption sites and reaction by-products such as NH4Cl and HCl that are generated by the reaction with the second gas and re-adsorbed on the surface of the substrate S are desorbed and removed from within the reaction tube 210.

[0124] Specifically, with the valve 264 open, the valve 276 is closed, and the valves 268, 258, and 254 are opened. An inert gas as a purge gas is supplied into the gas supply pipes 251 and 261 through the gas supply pipes 255 and 265. Meanwhile, the valves 282 and 283 of the exhaust pipe 281 are kept open, and the inside of the reaction tube 210 is evacuated by the vacuum pump 284. Thereby, the reaction between the first gas and the second gas in the gas phase existing in the reaction tube 210 can be suppressed.

[0125] (Performed a predetermined number of times) By performing the above-described first gas supply step and the second gas supply step in a non-simultaneous and sequential cycle a predetermined number of times (N times, where N is an integer of 1 or more) one or more times, a film with a predetermined thickness is formed on the substrate S having recesses. Here, for example, a SiN film is formed. That is, after the first gas supply step and the second gas supply step, the above-described step A is performed, and the cycle of performing the first gas supply step and the second gas supply step in a non-simultaneous and sequential manner is executed a predetermined number of times. Thereby, a film with improved step coverage performance can be formed on the substrate S having recesses.

[0126] (S110) Subsequently, the substrate unloading step S110 will be described. In S110, the processed substrate S is unloaded outside the transfer chamber 217 by the reverse procedure of the above-described substrate loading step S104.

[0127] (S112) Subsequently, the determination S112 will be described. Here, it is determined whether or not the substrate has been processed a predetermined number of times. If it is determined that the substrate has not been processed a predetermined number of times, the process returns to the substrate loading step S104 to process the next substrate S. If it is determined that the substrate has been processed a predetermined number of times, the process ends.

[0128] In the above description, the gas flow is described as horizontal in the formation of the gas flow. However, it is only necessary that the main gas flow is formed in the horizontal direction as a whole. As long as it does not affect the uniform processing of a plurality of substrates, a gas flow diffused in the vertical direction may also be acceptable.

[0129] Also, although expressions such as the same degree, equivalent, equal, etc. are used above, it goes without saying that these include substantially the same things.

[0130] (4) Variation (Variation 1) In the above-described aspect, the case of using the substrate S provided with adsorption sites on the surface in advance has been described. In this variation, a substrate S not provided with adsorption sites on the surface in advance is used. That is, before the first gas supply step in the above-described substrate processing step, the above-described second gas supply step is performed. That is, before performing step A described above, a step of forming adsorption sites such as NH groups in the concave portions of the substrate S is performed.

[0131] Specifically, a substrate S not provided with adsorption sites on the surface is carried into the reaction tube 210, and after performing step E and step F to form adsorption sites (for example, NH groups) on the surface of the concave portions of the substrate S, the first gas supply step and the second gas supply step are performed a predetermined number of times. Even in this case, the same effects as those of the above-described aspect can be obtained.

[0132] (Variation 2) In this variation, in the above-described second gas supply system 260, the tank 269 is not provided. That is, the second gas may be continuously supplied instead of being flash-supplied. Even in this case, the same effects as those of the above-described aspect can be obtained.

[0133] (Variation 3) In this variation, after performing steps A to F described above in this order, step C described above is performed. Even in this case, the same effects as those of the above-described aspect can be obtained.

[0134] (Other Embodiments) As described above, the embodiments of this aspect have been specifically described, but the present invention is not limited thereto, and various modifications can be made without departing from the gist thereof.

[0135] Further, for example, in each of the above-described embodiments, the case where 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 has been described as an example, but the present aspect is not limited thereto. That is, other types of thin films may be formed using other types of gas as the processing gas used in the film formation process. Furthermore, even when three or more types of processing gases are used, if the film formation process is performed by alternately supplying these gases, the present aspect can be applied.

[0136] Further, for example, in each of the above-described embodiments, the film formation process performed by the substrate processing apparatus has been described as an example, but the present aspect is not limited thereto. That is, in addition to the film formation process exemplified in each embodiment, the present aspect can also be applied to film formation processes other than the thin films exemplified in each embodiment. In addition, in the present embodiment, an apparatus for processing a plurality of substrates stacked has been described, but the present aspect is not limited thereto, and it can also be applied to a single-wafer apparatus that processes substrates one by one. Also, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can also be added to the configuration of one embodiment. Further, it is also possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

[0137] As described above, various typical embodiments of the present disclosure have been described, but the present disclosure is not limited to those embodiments and can also be used in appropriate combinations.

[0138] Hereinafter, examples will be described.

Example

[0139] In this example, the above-described substrate processing steps were performed using the substrate processing apparatus 10 shown in FIG. 1. FIG. 11(A) is a diagram showing the relationship between the number of steps of the first gas supply and the step coverage in this example. FIG. 11(B) is a diagram showing the relationship between the number of steps of the first gas supply in this example and the thickness of the layer formed on the upper or lower part of the substrate recess. FIG. 11(C) is a diagram for explaining the upper and lower parts of the substrate recess in this example.

[0140] As shown in FIGS. 11(A) and 11(B), it was confirmed that the difference between the thickness of the layer formed on the upper part in the substrate recess and the thickness of the layer formed on the lower part in the substrate recess was reduced by using this embodiment. That is, by using the above-described substrate processing step, it was confirmed that the step coverage was improved according to the number of steps of the first gas supply.

Explanation of Signs

[0141] S Substrate 10 Substrate processing apparatus 201 Processing chamber 210 Reaction tube 600…Controller

Claims

1. (a) A step of supplying a raw material gas to a recess of a substrate having adsorption sites on its surface at a rate faster than the adsorption rate at which a precursor of the raw material gas is adsorbed on the adsorption sites; (b) A step of supplying a purge gas to the recess; (c) A step of supplying the raw material gas to the recess at a rate slower than the adsorption rate; A method for manufacturing a semiconductor device, comprising the steps.

2. The raw material gas is decomposed into a first component adsorbed on the adsorption sites and a second component having an adsorption degree lower than that of the first component, The adsorption rate is the rate at which a precursor of the first component is adsorbed on the adsorption sites. The method for manufacturing a semiconductor device according to claim 1.

3. (d) After (c), a step of supplying a purge gas to the recess; (e) A step of supplying a reaction gas that reacts with the precursor of the raw material gas to the recess; The method for manufacturing a semiconductor device according to claim 1, comprising the steps.

4. After (e), (f) A step of supplying a purge gas to the recess is performed, and then (a) is performed. The method for manufacturing a semiconductor device according to claim 3.

5. After (e), (f) A step of supplying a purge gas to the recess is performed, and then (c) is performed. The method for manufacturing a semiconductor device according to claim 3.

6. After (c), (b) and (c) are repeated. The method for manufacturing a semiconductor device according to claim 1.

7. When repeating (b) and (c), the time of (b) when the number of repetitions is small is longer than the time of (b) when the number of repetitions increases. The method for manufacturing a semiconductor device according to claim 6.

8. When repeating (b) and (c), as the number of repetitions increases, the time of (b) becomes shorter. The method for manufacturing a semiconductor device according to claim 6.

9. When repeating (b) and (c), the time of (b) performed immediately after (a) is longer than the time of (b) performed immediately after (c). The method for manufacturing a semiconductor device according to any one of claims 6 to 8.

10. When repeating (b) and (c), the time of (c) when the number of repetitions is small is longer than the time of (c) when the number of repetitions increases. The method for manufacturing a semiconductor device according to any one of claims 6 to 9.

11. When repeating (b) and (c), as the number of repetitions increases, the time of (c) becomes shorter. The method for manufacturing a semiconductor device according to any one of claims 6 to 9.

12. The method of manufacturing a semiconductor device according to claim 1, further comprising a step of forming the adsorption site in the concave portion before (a).

13. The method of manufacturing a semiconductor device according to claim 1 or 12, further comprising a step of forming the adsorption site in the concave portion after (a).

14. The method of manufacturing a semiconductor device according to any one of claims 1 to 6, wherein the source gas is a gas having at least Si-Si bonds.

15. The raw material gas is Si ２ Cl ６ The method for manufacturing a semiconductor device according to claim 14, which is a gas.

16. The method of manufacturing a semiconductor device according to any one of claims 3 to 5, wherein the reaction gas is a gas containing hydrogen and nitrogen, and the adsorption site is an NH group.

17. In (a), the source gas in an undissociated state is supplied from the side of the substrate to collide the source gas with the concave portion, decomposing the source gas into the first component and the second component, and generating a predetermined amount of the first component in the concave portion. In (c), the source gas in an undissociated state is supplied from the side of the substrate to collide the source gas with the concave portion, decomposing the source gas into the first component and the second component, and generating an amount of the first component less than the predetermined amount in the concave portion. The method of manufacturing a semiconductor device according to claim 2.

18. A method of manufacturing a semiconductor device, comprising a step of supplying a source gas to a concave portion of a substrate having an adsorption site on its surface at a speed faster than the adsorption rate at which the precursor of the source gas is adsorbed on the adsorption site.

19. (a) A step of supplying a source gas to a concave portion of a substrate having an adsorption site on its surface at a speed faster than the adsorption rate at which the precursor of the source gas is adsorbed on the adsorption site. (b) A step of supplying a purge gas to the concave portion. (c) A step of supplying the source gas to the concave portion at a speed slower than the adsorption rate. A substrate processing method comprising the above steps.

20. A processing chamber for processing a substrate. A gas supply unit capable of supplying a source gas into the processing chamber. (a) A process of supplying a source gas to a concave portion of a substrate having an adsorption site on its surface in the processing chamber at a speed faster than the adsorption rate at which the precursor of the source gas is adsorbed on the adsorption site. (b) A process of supplying a purge gas to the concave portion. (c) A process of supplying the source gas to the concave portion at a speed slower than the adsorption rate. A control unit configured to be able to control the gas supply unit so as to perform the above processes. A substrate processing apparatus comprising the above components.

21. A procedure of supplying a precursor of a source gas to a concave portion of a substrate having adsorption sites on its surface in a processing chamber of a substrate processing apparatus at a speed higher than an adsorption speed at which the precursor of the source gas is adsorbed to the adsorption sites, a procedure of supplying a purge gas to the concave portion, a procedure of supplying the source gas to the concave portion at a speed lower than the adsorption speed, and a program for causing the substrate processing apparatus to execute using a computer.

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