Substrate processing apparatus, method of manufacturing semiconductor device, storage medium, and inner tube

Abstract

The present invention provides a substrate processing apparatus comprising: an inner tube having an inner tube having a substrate storage area therein for arranging and storing multiple substrates in a horizontal orientation along a predetermined arrangement direction; an outer tube disposed on the outer side of the inner tube; multiple gas supply ports disposed on the sidewall of the inner tube along the arrangement direction; multiple first exhaust ports disposed on the sidewall of the inner tube along the arrangement direction; a second exhaust port disposed on one end of the outer tube along the arrangement direction; and a rectification mechanism for controlling the gas flow in an annular space between the inner tube and the outer tube, wherein the rectification mechanism has a first fin near the first exhaust port closest to the second exhaust port among the multiple first exhaust ports, i.e., exhaust port A between the exhaust port and the second exhaust port.

Description

Technical Field

[0001] This disclosure relates to a substrate processing apparatus, a method for manufacturing a semiconductor device, a storage medium, and an inner tube. Background Technology

[0002] As a step in the manufacturing process of a semiconductor device, there is sometimes a process of supplying gas to a processing chamber that houses multiple substrates and processing the substrates (see, for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-088520 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] This disclosure improves the uniformity of processing between multiple substrates.

[0008] Solution for solving the problem

[0009] According to one aspect of this disclosure, a substrate processing apparatus is provided, comprising:

[0010] The inner tube has a substrate storage area inside which multiple substrates are arranged in a horizontal posture along a predetermined arrangement direction to form multiple layers and are stored therein.

[0011] An outer tube, which is disposed on the outside of the inner tube;

[0012] Gas supply ports are provided in multiple locations along the arrangement direction on the side wall of the inner tube;

[0013] The first exhaust port has multiple outlets arranged along the arrangement direction on the side wall of the inner tube;

[0014] A second exhaust port is disposed at one end of the outer pipe along the arrangement direction; and

[0015] A rectifier mechanism controls the gas flow within the annular space between the inner and outer tubes.

[0016] The rectifier has a first fin near the first exhaust port closest to the second exhaust port among a plurality of first exhaust ports, i.e., exhaust port A between the second exhaust port and the first exhaust port.

[0017] Invention Effects

[0018] According to this disclosure, when processing multiple substrates, the uniformity of processing between substrates can be improved. Attached Figure Description

[0019] Figure 1 This is a schematic structural diagram of a vertical processing furnace of a substrate processing apparatus preferred in one embodiment of the present disclosure, showing the furnace portion in a longitudinal sectional view.

[0020] Figure 2 This is a diagram illustrating the structure of the gas supply system of a vertical processing furnace in a substrate processing apparatus preferably used in one embodiment of the present disclosure.

[0021] Figure 3 This is a schematic structural diagram of a controller for a substrate processing apparatus preferably used in one embodiment of the present disclosure, and a block diagram showing the control system of the controller.

[0022] Figure 4 This is a schematic structural diagram of a vertical processing furnace of a substrate processing apparatus preferred for use in one embodiment of the present disclosure. Figure 1 The BB line section view shows a diagram of the main parts of the processing furnace.

[0023] Figure 5 This is a diagram illustrating a structural example of the main parts of a substrate processing apparatus according to one embodiment of the present disclosure. Figure 5 (a) is from Figure 4 A diagram showing the outer wall of the internal tube 21 viewed from direction C. Figure 5 (b) is from Figure 4 A diagram showing the outer wall of the internal tube 21 viewed from direction D. Figure 5 (c) is from Figure 4 A diagram showing the outer wall of the internal tube 21 viewed from direction E.

[0024] Figure 6 of (a), Figure 6 (b) is a diagram showing the flow of exhaust gas from the first exhaust ports 41a and 41b provided in the inner pipe 21 into the annular space between the inner pipe 21 and the outer pipe 22 and toward the second exhaust port 91 provided in the outer pipe 22.

[0025] Figure 7 of (a), Figure 7 (b) shows the flow of exhaust gas from the first exhaust ports 41a and 41b provided in the inner pipe 21 into the annular space between the inner pipe 21 and the outer pipe 22 and toward the second exhaust port 91 provided in the outer pipe 22. Detailed Implementation

[0026] <One way this disclosure>

[0027] The following is for reference Figures 1-4 , Figure 5 (a)~ Figure 5 (c) describes one aspect of this disclosure.

[0028] (1) Structure of the substrate processing device

[0029] The substrate processing apparatus of this method is an apparatus used in the manufacturing process of semiconductor devices, and is configured as a vertical substrate processing apparatus that aggregates and processes multiple substrates (e.g., 5 to 100) that are to be processed. Examples of substrates to be processed include semiconductor wafer substrates (hereinafter simply referred to as "wafers") used for manufacturing semiconductor integrated circuit devices (semiconductor devices).

[0030] like Figure 1 As shown, the substrate processing apparatus of this embodiment includes a vertical processing furnace 1. The vertical processing furnace 1 has a heater 10 that serves as a heating unit (heating mechanism, heating system). The heater 10 is cylindrical in shape and is vertically mounted relative to the mounting floor (not shown) of the substrate processing apparatus by means of a heater base (not shown) that serves as a holding plate. The heater 10 also functions as an activation mechanism (activation unit) for thermally activating (exciting) gases.

[0031] Inside the heater 10, a reaction tube 20 constituting a reaction vessel (processing vessel) is arranged concentrically with the heater 10. The reaction tube 20 has a double-tube structure, comprising an inner tube 21 serving as the inner tube and an outer tube 22 surrounding the inner tube 21 in a concentric circle. The inner tube 21 and the outer tube 22 are respectively made of heat-resistant materials such as quartz (SiO2) or silicon carbide (SiC). The inner tube 21 and the outer tube 22 are each formed into a cylindrical shape that is closed at the top and open at the bottom.

[0032] A processing chamber 23 for processing wafers 200 is formed inside the internal tube 21. The processing chamber 23 is configured to house multiple wafers 200 in a multi-layer arrangement in a horizontal orientation along a predetermined arrangement direction (here, vertical direction) using a crystal boat 40 described later. In this specification, the direction in which the multiple wafers 200 are arranged within the processing chamber 23 is also referred to as the arrangement direction. Furthermore, the area within the processing chamber 23 where the multiple wafers 200 are housed in a horizontal orientation along the arrangement direction is also referred to as the substrate housing area 65.

[0033] A sealing cover 50, serving as a furnace opening cover, is provided below the reaction tube 20 to airtightly seal the lower opening of the reaction tube 20. The sealing cover 50 is made of a metal material such as stainless steel (SUS) and is formed in a disc shape. An O-ring (not shown) is provided on the upper surface of the sealing cover 50 as a sealing member that abuts against the lower end of the reaction tube 20. The sealing cover 50 is configured to be raised and lowered vertically by a crystal boat lift (not shown) serving as a lifting mechanism. The crystal boat lift mechanism is a conveying device (transfer mechanism) that moves the crystal boat 40, which holds the wafer 200, into and out of the processing chamber 23 by raising and lowering the sealing cover 50.

[0034] A substrate loading / unloading outlet (not shown) is provided below the sealing cover 50. The wafer 200 is moved inside and outside the transfer chamber (not shown) by a transfer robot (not shown) via the substrate loading / unloading outlet. The wafer 200 is loaded into the crystal boat 40 and unloaded from the crystal boat 40 within the transfer chamber.

[0035] The crystal boat 40, serving as a substrate support, is configured to support multiple wafers (e.g., 5 to 100 wafers) 200 in a horizontal orientation and with their centers aligned, arranged in multiple layers along a predetermined arrangement direction (here, the vertical direction), i.e., arranged at intervals. The crystal boat 40 is made of heat-resistant materials such as quartz or SiC. A heat-insulating part 42 is provided at the lower part of the crystal boat 40, which is configured as a heat-insulating cylinder made of heat-resistant materials such as quartz or SiC. The heat-insulating part 42 may also be constructed by supporting multiple layers of heat-insulating plates made of heat-resistant materials such as quartz or SiC in a horizontal orientation.

[0036] In the reaction tube 20, multiple nozzles 30, which supply gas to the inner tube 21, are arranged in the aforementioned arrangement direction (vertical direction). Furthermore, they are arranged to pass through the heater 10 and the outer tube 22 from the side. Additionally, one nozzle 30 is provided for each wafer 200 housed within the substrate housing region 65. The nozzles 30 are mounted such that they can spray gas in a direction substantially parallel to the surface of the wafer 200 housed within the substrate housing region 65.

[0037] like Figure 5As shown in (a), a plurality of gas supply ports 31 are arranged along the aforementioned arrangement direction (here, vertical direction) on the sidewall of the inner tube 21, for introducing gas supplied from the nozzle 30 into the inner tube 21. Furthermore, one gas supply port 31 is provided for each wafer 200 housed within the substrate housing region 65. Additionally, the plurality of gas supply ports 31 are respectively positioned opposite the front ends of the plurality of nozzles 30. In this specification, the gas supply port 31 located at the bottom of the plurality of gas supply ports 31 (the gas supply port 31 opposite the first exhaust port 41a described later) is also referred to as gas supply port 31a. Furthermore, gas supply ports 31 that are different from the first exhaust port 41a, such as the gas supply port 31 located at the top (the gas supply port 31 opposite the first exhaust port 41b described later), are also referred to as gas supply port 31b.

[0038] like Figure 2 As shown, gas supply pipes 51 are connected to nozzles 30. On gas supply pipes 51, a mass flow controller (MFC) 51a (flow control unit) and a valve 51b (on / off valve) are sequentially arranged from the upstream side of the airflow. Gas supply pipes 52 and 53 are connected downstream of valve 51b on gas supply pipes 51. On gas supply pipes 52 and 53, MFCs 52a and 53a and valves 52b and 53b are sequentially arranged from the upstream side of the airflow, respectively.

[0039] As a feed gas, a silane gas, such as silicon (Si), which is the main element constituting the film formed on the wafer 200, is supplied from the gas supply pipe 51 into the processing chamber 23 via MFC 51a, valve 51b, and nozzle 30. For example, hexachlorosilane (Si2Cl6, abbreviated as HCDS) gas can be used as a silane-based gas.

[0040] As the reaction gas, a nitrogen gas, for example, can be supplied from the gas supply pipe 52 into the processing chamber 23 via MFC 52a, valve 52b, gas supply pipe 51, and nozzle 30. For example, ammonia (NH3) gas can be used as the nitrogen gas.

[0041] Nitrogen (N2) is supplied as an inert gas from gas supply pipe 53 through MFC 53a, valve 53b, gas supply pipe 51, and nozzle 30 into processing chamber 23. N2 gas functions as a purge gas, dilution gas, or carrier gas.

[0042] like Figure 4 As shown, a first exhaust port 41 is provided on the side wall of the internal tube 21, across the aforementioned substrate storage area 65, opposite the gas supply port 31. Figure 1 and Figure 5As shown in (c), multiple first exhaust ports 41 are arranged in the aforementioned arrangement direction (here, the vertical direction). The first exhaust ports 41 are configured to discharge gas supplied from the gas supply port 31 to the internal tube 21 from within the internal tube 21. Furthermore, one first exhaust port 41 is provided for each gas supply port 31, i.e., for each wafer 200 housed within the substrate housing area 65. In this specification, the first exhaust port 41 closest to the second exhaust port 91 (described later), i.e., the lowermost first exhaust port 41, is also referred to as exhaust port A (first exhaust port 41a). Additionally, exhaust ports that differ from first exhaust port 41a, such as the first exhaust port 41 furthest from the second exhaust port 91 (the uppermost first exhaust port 41), are also referred to as exhaust port B (first exhaust port 41b).

[0043] A second exhaust port 91 is provided at one end (the lower end) of the outer tube 22 along the aforementioned arrangement direction (here, the vertical direction) to discharge the gas discharged from the inner tube 21 to the outer tube 22 via each of the plurality of first exhaust ports 41, i.e., the exhaust gas flowing in the annular space between the inner tube 21 and the outer tube 22, to the outside of the reaction tube 20. An exhaust pipe 61 is connected to the second exhaust port 91. A vacuum pump 64, which serves as a vacuum exhaust device, is connected to the exhaust pipe 61 via a pressure sensor 62, which acts as a pressure detector (pressure detection unit) for detecting the pressure inside the reaction tube 20, and an APC (AutoPressure Controller) valve 63, which acts as a pressure regulator (pressure adjustment unit). The APC valve 63 is configured such that by opening and closing the valve while the vacuum pump 64 is operating, vacuum exhaust in the processing chamber 23 can be performed and stopped. Furthermore, while the vacuum pump 64 is operating, the valve opening is adjusted based on the pressure information detected by the pressure sensor 62, thereby adjusting the pressure inside the processing chamber 23. The exhaust system, or exhaust pipeline, mainly consists of exhaust pipe 61, APC valve 63, and pressure sensor 62.

[0044] Between the inner pipe 21 and the outer pipe 22, there is a rectifier R that controls the gas flow within the annular space (hereinafter also referred to as the exhaust buffer space) between the inner pipe 21 and the outer pipe 22, that is, the flow (exhaust path) of the exhaust gas discharged from each of the plurality of first exhaust ports 41 into the exhaust buffer space and toward the second exhaust port 91. The specific structure of the rectifier R will be described later.

[0045] A temperature sensor 11, acting as a temperature detector, is installed between the inner tube 21 and the outer tube 22. By adjusting the power supply to the heater 10 based on the temperature information detected by the temperature sensor 11, the temperature within the processing chamber 23 is adjusted to achieve the desired temperature distribution. Figure 5 As shown in (b), the temperature sensor 11 is configured in an L-shape, for example, along the outer wall of the inner tube 21.

[0046] like Figure 3 As shown, the controller 70, serving as the control unit (control unit), is configured as a computer equipped with a CPU (Central Processing Unit) 71, RAM (Random Access Memory) 72, a storage device 73, and an I / O port 74. The RAM 72, storage device 73, and I / O port 74 are configured to exchange data with the CPU 71 via an internal bus 75. An input / output device 82, such as a touch panel, and an external storage device 81 are connected to the controller 70.

[0047] The storage device 73 is configured, for example, with flash memory or an HDD (Hard Disk Drive). The storage device 73 contains readable storage of control programs that control the operation of the substrate processing apparatus, and process procedures that describe the steps and conditions of the semiconductor device manufacturing method (described later). The process procedure is a combination of steps in the semiconductor device manufacturing method (described later) that enables the controller 70 to execute and obtain a predetermined result, and functions as a program. Hereinafter, the process procedure, control program, etc., will be collectively referred to as a program. The process procedure will also be simply referred to as a process. When the term "program" is used in this specification, it may sometimes refer only to a single process unit, only to a single control program unit, or both. The RAM 72 is configured as a storage area (working area) for temporarily holding programs, data, etc., read by the CPU 71.

[0048] I / O port 74 is connected to the aforementioned MFCs 51a-53a, valves 51b-53b, pressure sensor 62, APC valve 63, vacuum pump 64, heater 10, temperature sensor 11, etc.

[0049] The CPU 71 is configured to read and execute the control program from the storage device 73, and to read the process from the storage device 73 based on input commands from the input / output device 82. The CPU 71 is configured to control the flow rate adjustment of various gases based on MFC 51a to 53a, the opening and closing of valves 51b to 53b, the opening and closing of APC valve 63, the pressure adjustment of APC valve 63 based on pressure sensor 62, the start and stop of vacuum pump 64, the temperature adjustment of heater 10 based on temperature sensor 11, and the lifting and lowering of crystal boat 40 based on lifting mechanism, etc., according to the read process content.

[0050] The controller 70 is configured to install the aforementioned program stored in the external storage device 81 onto a computer. The external storage device 81 includes, for example, magnetic tape, HDD, CD, MO, and USB storage devices. The storage device 73 and the external storage device 81 constitute a computer-readable storage medium. Hereinafter, they will be collectively referred to as storage media. When the term "storage medium" is used in this specification, it may refer only to the storage device 73, only to the external storage device 81, or both. Furthermore, when providing a program to a computer, it may be possible to do so without using the external storage device 81, but instead using communication methods such as the Internet or dedicated lines.

[0051] (2) Substrate processing process

[0052] Using the above-described substrate processing apparatus as a step in the manufacturing process of a semiconductor device, an example of the sequence for forming a film on a wafer 200, which serves as a substrate, will be described. In the following description, the operation of each component constituting the substrate processing apparatus is controlled by a controller 70.

[0053] In this method, the steps of supplying HCDS gas as a raw material gas to the wafer 200 housed in the processing container (processing chamber 23) and supplying NH3 gas to the wafer 200 housed in the processing chamber 23 are performed non-simultaneously, i.e., not synchronously, for a predetermined number of times (n times, where n is an integer greater than or equal to 1), thereby forming a silicon nitride film (SiN film) on the wafer 200.

[0054] In this specification, for convenience, the above-described film-forming treatment is sometimes referred to as follows. The same notation is also used in other descriptions below.

[0055]

[0056] (Wafer loading and boat import)

[0057] When multiple wafers 200 are loaded (wafer loading) into the crystal boat 40, the crystal boat 40 supporting the multiple wafers 200 is lifted by the crystal boat elevator and moved into the processing chamber 23 (crystal boat introduction). In this state, the sealing cap 50 is sealed to the lower end of the reaction tube 20 via an O-ring.

[0058] (Pressure / Temperature Adjustment Procedure)

[0059] Vacuum pump 64 performs vacuum venting (pressure reduction venting) to achieve the required pressure (vacuum) within processing chamber 23, i.e., the space containing wafer 200. During this time, pressure sensor 62 measures the pressure within reaction tube 20, and based on this measured pressure information, APC valve 63 is controlled to adjust the pressure within processing chamber 23 to the required level. Vacuum pump 64 remains continuously operational at least until the processing of wafer 200 is complete. Furthermore, wafer 200 within processing chamber 23 is heated by heater 10 to achieve the required film deposition temperature. During this time, the energization of heater 10 is controlled based on temperature information detected by temperature sensor 11 to achieve the required temperature distribution within processing chamber 23. Heating of processing chamber 23 by heater 10 continues at least until the processing of wafer 200 is complete.

[0060] (Film-forming steps)

[0061] Next, perform steps 1 and 2 in sequence.

[0062] [Step 1]

[0063] In this step, HCDS gas is supplied to the wafer 200 inside the processing chamber 23.

[0064] Specifically, valve 51b is opened, allowing HCDS gas to flow into gas supply pipe 51. The HCDS gas flow rate is adjusted by MFC 51a and supplied into processing chamber 23 (inner pipe 21) via nozzle 30 and gas supply port 31. The HCDS gas supplied into inner pipe 21 flows in a direction parallel to the surface of wafer 200 (horizontal direction), is discharged out of inner pipe 21 via first exhaust port 41, passes through the annular space (exhaust buffer space) between inner pipe 21 and outer pipe 22, and is discharged from second exhaust port 91. At this time, HCDS gas is supplied to each of the multiple wafers 200. Then, valve 53b is opened, allowing N2 gas to flow into gas supply pipe 53. The N2 gas flow rate is adjusted by MFC 53a and supplied into inner pipe 21 via nozzle 30 and gas supply port 31. N2 gas acts as a carrier gas.

[0065] At this time, the pressure inside the processing chamber 23 is, for example, in the range of 0.1 to 30 Torr, preferably 0.2 to 20 Torr, and more preferably 0.3 to 13 Torr. The supply flow rate of HCDS gas is, for example, in the range of 0.1 to 10 slm, and preferably 0.2 to 2 slm. The supply flow rate of N2 gas is, for example, in the range of 0.1 to 20 slm. The supply time of HCDS gas is, for example, in the range of 0.1 to 60 seconds, and preferably in the range of 0.5 to 5 seconds. The temperature of the heater 10 is set such that the temperature of the wafer 200 is, for example, in the range of 200 to 900°C, preferably 300 to 850°C, and more preferably 400 to 750°C.

[0066] By supplying HCDS gas to wafer 200, a Si-containing layer is formed as the first layer on the outermost surface of each of the multiple wafers 200.

[0067] After the first layer is formed, valve 51b is closed, stopping the supply of HCDS gas to the internal tube 21. At this time, APC valve 63 remains open, and vacuum pump 64 is used to ventilate the reaction vessel 20, removing any unreacted or harmful HCDS gas remaining in the processing chamber 23. Meanwhile, valve 53b remains open, maintaining the supply of N2 gas to the processing chamber 23. N2 gas acts as a purging gas, enhancing the removal of any remaining gas from the processing chamber 23. After purging, valve 53b is closed, stopping the supply of N2 gas to the processing chamber 23.

[0068] [Step 2]

[0069] After step 1 is completed, NH3 gas is supplied to the wafer 200 in the processing chamber 23.

[0070] Specifically, valve 52b is opened, allowing NH3 gas to flow into gas supply pipe 52. The flow rate of NH3 gas is adjusted by MFC 52a and supplied into processing chamber 23 (inner pipe 21) via gas supply pipe 51, nozzle 30, and gas supply port 31. The NH3 gas supplied into inner pipe 21 flows in a direction parallel to the surface of wafer 200 (horizontal direction), exits from inner pipe 21 through first exhaust port 41, passes through the annular space between inner pipe 21 and outer pipe 22, and exits from second exhaust port 91. At this time, NH3 gas is supplied to each of the multiple wafers 200. Then, valve 53b is opened, allowing N2 gas to flow into gas supply pipe 53. The flow rate of N2 gas is adjusted by MFC 53a and supplied into inner pipe 21 via nozzle 30 and gas supply port 31. N2 gas acts as a carrier gas.

[0071] At this time, the pressure inside the processing chamber 23 is, for example, in the range of 0.1 to 30 Torr, preferably 0.2 to 20 Torr, and more preferably 0.3 to 13 Torr. The supply flow rate of HCDS gas is, for example, in the range of 0.1 to 10 slm, and preferably 0.2 to 2 slm. The supply flow rate of N2 gas is, for example, in the range of 0.1 to 20 slm. The supply time of HCDS gas is, for example, in the range of 0.1 to 60 seconds, and preferably in the range of 0.5 to 5 seconds. The temperature of the heater 10 is set such that the temperature of the wafer 200 is, for example, in the range of 200 to 900°C, preferably 300 to 850°C, and more preferably 400 to 750°C.

[0072] The NH3 gas supplied to wafer 200 reacts with at least a portion of the first layer, i.e., the Si-containing layer, formed on wafer 200 in step 1. As a result, the first layer is non-plasma thermally nitrided, transforming (modifying) into a second layer containing Si and N, i.e., a silicon nitride layer (SiN layer).

[0073] After the second layer (SiN layer) is formed, valve 52b is closed to stop the supply of NH3 gas to the internal tube 21. Then, the NH3 gas and reaction byproducts remaining in the processing chamber 23 are removed from the processing chamber 23 through the same processing steps as in step 1.

[0074] [Number of scheduled implementations]

[0075] By performing steps 1 and 2 separately, i.e., not synchronously, a predetermined number of cycles (n times, where n is an integer greater than or equal to 1) can be performed on wafer 200, a SiN film of a predetermined thickness can be formed. Preferably, the above cycle is repeated multiple times. That is, it is preferable to make the thickness of the second layer formed in each cycle smaller than the desired film thickness, and to repeat the above cycle multiple times until the film thickness formed by stacking the second layer reaches the desired film thickness.

[0076] (Post-purging steps / Atmospheric pressure recovery steps)

[0077] After the film formation step is completed and a SiN film of the predetermined thickness is formed, N2 gas is supplied into the reaction tube 20 and discharged from the exhaust pipe 61. This purges the processing chamber 23, removing any residual gas and reaction byproducts (post-purge). Subsequently, the atmosphere in the processing chamber 23 is replaced with an inert gas (inert gas replacement), and the pressure inside the processing chamber 23 is restored to atmospheric pressure (atmospheric pressure restoration).

[0078] (Crystal boat export and wafer unloading)

[0079] Next, the sealing cover 50 is lowered using a crystal boat lift, opening the lower end of the reaction tube 20, and the processed wafer 200 is moved out of the reaction tube 20 while supported by the crystal boat 40 (crystal boat export). After the processed wafer 200 is moved out of the reaction tube 20, it is removed from the crystal boat 40 (wafer unloading).

[0080] (3) Structure of rectifier R

[0081] The structure of the rectifier R, which controls the flow (flow path, specifically the path length) of the exhaust gas within the annular space between the inner pipe 21 and the outer pipe 22, will be described below. As mentioned above, in this specification, the annular space between the inner pipe 21 and the outer pipe 22 is also referred to as the "exhaust buffer space".

[0082] Figure 6 Figure (a) illustrates the path of the exhaust gas in the exhaust buffer space when the rectifier R is not provided. "Exhaust path A" schematically shows the path of the exhaust gas from the first exhaust port 41a, which is closest to the second exhaust port 91 among the plurality of first exhaust ports 41, toward the second exhaust port 91. "Exhaust path B" schematically shows the path of the exhaust gas from a first exhaust port 41b, which is different from the first exhaust port 41a, toward the second exhaust port 91. As shown in the figure, without the rectifier R provided in the exhaust buffer space, the length of exhaust path A is shorter than that of exhaust path B.

[0083] In the structure shown here, due to the different lengths of the exhaust paths, there is a tendency for the velocity of the exhaust gas flowing in exhaust path A to be greater than that of the exhaust gas flowing in exhaust path B. Furthermore, there is a tendency for the velocity of the processing gas (raw material gas, reactant gas) flowing horizontally from gas supply port 31a toward the first exhaust port 41a to be greater than that of the processing gas flowing horizontally from gas supply port 31b toward the first exhaust port 41b. As a result, there is a tendency for the supply amount of processing gas to the lower wafer 200 disposed within the substrate housing region 65 to be greater than the supply amount of processing gas to the upper wafer 200 disposed within the substrate housing region 65. Moreover, the thickness of the SiN film formed on the wafers 200 sometimes becomes uneven between the wafers 200. Specifically, sometimes the thickness of the SiN film formed on the lower wafer 200 disposed within the substrate housing region 65 is greater than the thickness of the SiN film formed on the upper wafer 200 disposed within the substrate housing region 65.

[0084] To address this issue, in this approach, such as Figure 5 (a)~ Figure 5As shown in (c), a rectifier R (including the rectifier plate group consisting of the first fin 300, the second fin 400, and the third fin 500, described later) is provided in the exhaust buffer space to control the flow (flow path) of the exhaust gas in the exhaust buffer space.

[0085] like Figure 5 (b) Figure 5 As shown in (c), the rectifier R is located near the first exhaust port 41a, specifically directly below the first exhaust port 41a (on the side of the second exhaust port 91). The first fin 300 is configured as a rectifier plate protruding radially outward from the outer wall of the inner tube 21 toward the inner wall of the outer tube 22. A predetermined gap, for example, a gap greater than 2 mm and less than 7 mm, is maintained between the end of the first fin 300 toward the radially outward of the inner tube 21 and the inner wall of the outer tube 22.

[0086] In addition, such as Figure 4 As shown, the first fin 300 is disposed on the outer wall of the inner tube 21 near the first exhaust port 41a, extending horizontally along its outer periphery. The first fin 300 is disposed on the outer wall of the inner tube 21 along its outer periphery for a predetermined length (extension length) greater than the inner diameter in the horizontal direction of the exhaust port A. The first fin 300 is configured such that, when viewed from above, the angle θ connecting the central axis 150 of the inner tube 21 to each of the two ends of the first fin 300 along the outer periphery of the inner tube 21 is a predetermined angle, for example, 20° to 180°.

[0087] By setting the first fin 300 in these ways, such as Figure 6 As shown in (b), the exhaust gas discharged from the first exhaust port 41a can be made to meander a predetermined distance in the horizontal direction (circumferential direction of the internal pipe 21). This allows the length of exhaust path A to be extended, making it close to the length of exhaust path B. As a result, the velocity of the exhaust gas flowing in exhaust path A can be appropriately reduced, making it close to the velocity of the exhaust gas flowing in exhaust path B. Furthermore, the velocity of the processing gas flowing horizontally from gas supply port 31a toward the first exhaust port 41a can be appropriately reduced, making the velocity of the processing gas flowing horizontally from gas supply port 31b toward the first exhaust port 41b close to that of the processing gas. As a result, the supply amount of processing gas in the lower wafer 200 disposed within the substrate housing region 65 can be appropriately reduced, making it close to the supply amount of processing gas in the upper wafer 200 disposed within the substrate housing region 65. Moreover, the thickness of the SiN film formed on the wafer 200 can be adjusted to a uniform direction between the wafers 200.

[0088] In addition, the rectifier mechanism R in this method has a second fin 400 in addition to the first fin 300.

[0089] The second fin 400 is disposed near the first exhaust port 41, which is different from the first exhaust port 41a, and specifically, it is disposed directly below the first exhaust port 41b. Like the first fin 300, the second fin 400 is configured as a flow straightener protruding radially outward from the outer wall of the inner tube 21 toward the inner wall of the outer tube 22, i.e., toward the radially outward side of the inner tube 21. Similar to the first fin 300, a gap is formed between the end of the second fin 400 toward the radially outward side of the inner tube 21 and the inner wall of the outer tube 22, maintaining a predetermined distance, for example, a distance greater than 2 mm and less than 7 mm.

[0090] Furthermore, similarly to the first fin 300, the second fin 400 extends horizontally along its outer periphery on the outer wall of the inner tube 21 near the first exhaust port 41b, with a predetermined length (extension length) larger than the horizontal inner diameter of the first exhaust port 41b. The extension length of the second fin 400 is shorter than the extension length of the first fin 300 (see reference). Figure 5 (c) Figure 6 (b)

[0091] In addition, a second fin 400 is provided for each of the multiple first exhaust ports 41, which is different from the first exhaust port 41a. The extension length of the multiple second fins 400 increases with the distance from the second exhaust port 91, that is, the position of the second fins 400 gradually shortens as they move from bottom to top.

[0092] By arranging the second fins 400 in these manner, the exhaust gases discharged from the plurality of first exhaust ports 41b can be made to meander a predetermined distance in the horizontal direction (circumferential direction of the internal tube 21). Furthermore, the meandering distance of each exhaust gas discharged from the plurality of first exhaust ports 41b can be made to gradually shorten as the position of the first exhaust ports 41b moves further away from the second exhaust port 91. This further unifies the length of the exhaust path of the exhaust gas from the first exhaust ports 41 towards the second exhaust port 91 among the plurality of first exhaust ports 41. Additionally, the velocity of the process gas flowing horizontally from the gas supply port 31 towards the first exhaust port 41 can be further unified among the plurality of gas supply ports 31, i.e., among the plurality of wafers 200. As a result, the film thickness of the SiN film formed on the wafers 200 can be further unified among the wafers 200.

[0093] Furthermore, even when the exhaust buffer space is equipped with the first fin 300 and the second fin 400, such as Figure 7As shown in (a), the path of exhaust path B sometimes varies depending on conditions, etc. In this case, although the above-mentioned effect can be fully obtained, within the range where the effect can be obtained, the velocity of the exhaust gas discharged from the first exhaust port 41 is slightly uneven among the multiple first exhaust ports 41, which may affect the uniformity of the film thickness of the SiN film formed on the wafer 200 between wafers 200.

[0094] Therefore, in order to achieve the above-mentioned effect more stably, the rectifier R in this method also has a third fin 500 in addition to the first fin 300 and the second fin 400.

[0095] The third fin 500, like the first fin 300, is configured as a flow straightener protruding radially outward from the outer wall of the inner tube 21 toward the inner wall of the outer tube 22, i.e., toward the radially outer side of the inner tube 21. Similarly to the first fin 300, a gap, maintaining a predetermined distance—for example, a distance greater than 2 mm and less than 7 mm—is formed between the end of the third fin 500 toward the radially outer side of the inner tube 21 and the inner wall of the outer tube 22.

[0096] like Figure 7 As shown in (b), the third fin 500 extends in a direction different from the direction along the outer periphery of the sidewall of the inner tube 21, that is, a direction different from the direction in which the first fin 300 and the second fin 400 extend (horizontal direction) (a direction with a vertical component). More specifically, the third fin 500 is configured as a straight line (flat plate) and is inclined at a predetermined angle relative to the vertical direction, gradually moving towards the gas supply port 31 as it moves vertically downward. The ends (upper and lower ends) of the third fin 500 extend to the position where the gas flowing horizontally at the ends of the first fin 300 and the second fin 400 collides.

[0097] In addition, such as Figure 5 (a)~ Figure 5 As shown in (c), the third fin 500 has multiple fins arranged circumferentially along the inner tube 21, that is, respectively arranged on two paths from the first exhaust port 41 toward the second exhaust port 91. Additionally, as... Figure 5 As shown in (b), the third fin 500 is disposed at each end of the first fin 300 and the second fin 400, which extend horizontally, at a predetermined distance from the ends of the outer periphery of the sidewall of the inner tube 21. The distance D1 between the end of the first fin 300 along the outer periphery of the sidewall of the inner tube 21 and the third fin 500 is greater than the distance D2 between the first fin 300 and the second fin 400 adjacent to the first fin 300 along the aforementioned arrangement direction (here, the vertical direction). For example, the distance D1 can be set to twice the distance D2. The third fin 500 is disposed such that its lower end is positioned above the lower end of the heater 10.

[0098] By arranging the third fin 500 in this manner, the exhaust gas discharged from the first exhaust port 41b can quickly change its path towards the second exhaust port 91 after meandering a predetermined distance horizontally using the second fin 400. As a result, the length of the exhaust path of the exhaust gas from the first exhaust port 41 to the second exhaust port 91 can be more reliably consistent among the multiple first exhaust ports 41. Furthermore, by setting the distance between the third fin 500 and the first fin 300 and the second fin 400 as described above, even if gas is concentrated from above around the periphery of the first fin 300, this gas can be directed towards the second exhaust port 91 without stagnation. Additionally, by arranging the third fin 500, the exhaust gas will not come into contact with the temperature sensor 11 provided along the outer wall of the inner tube 21, enabling accurate temperature detection.

[0099] (4) The effect of this method

[0100] According to this method, one or more of the following effects are achieved.

[0101] (a) In this method, since a first fin 300 is provided near the first exhaust port 41a between the first exhaust port 41a and the second exhaust port 91, the exhaust gas discharged from the first exhaust port 41a can be made to meander a predetermined distance along the circumferential (horizontal) direction of the internal pipe 21. This extends the length of exhaust path A, making it close to the length of exhaust path B. According to this method, the velocity of the processing gas flowing horizontally from the gas supply port 31a toward the first exhaust port 41a can be appropriately reduced, and the velocity of the processing gas flowing horizontally from the gas supply port 31b toward the first exhaust port 41b can be brought closer. As a result, the supply amount of processing gas relative to the plurality of wafers 200 disposed within the substrate housing region 65 can be made consistent, and the thickness of the SiN film formed on the wafers 200 can be adjusted to a consistent direction among the wafers 200.

[0102] (b) In this embodiment, the first fin 300 is arranged along the outer periphery of the sidewall of the inner tube 21 by a predetermined length (extension length) larger than the inner diameter in the horizontal direction of the first exhaust port 41a. This allows the exhaust gas discharged from the first exhaust port 41a to reliably meander a predetermined distance circumferentially (horizontally) towards the inner tube 21. As a result, the thickness of the SiN film formed on the wafer 200 can be reliably consistent across the wafers 200.

[0103] (c) In this embodiment, a second fin 400 is provided near the first exhaust port 41b between exhaust port B (first exhaust port 41b) and the second exhaust port 91. Furthermore, the second fin 400 is provided along the outer periphery of the sidewall of the inner tube 21 with a predetermined length (extension length) larger than the horizontal inner diameter of the first exhaust port 41b. This allows the exhaust gases discharged from the multiple first exhaust ports 41b to meander a predetermined distance horizontally (circumferentially). According to this embodiment, not only the length of exhaust path A but also the length of exhaust path B can be adjusted, thus enabling more reliable alignment of the lengths of exhaust path A and B. As a result, the thickness of the SiN film formed on the wafer 200 can be more reliably consistent across the wafers 200.

[0104] (d) In this embodiment, a plurality of second fins 400 are provided along the aforementioned arrangement direction (here, the vertical direction). The length of the plurality of second fins 400 is configured to gradually decrease as the distance from the second exhaust port 91 increases. Therefore, the length of the exhaust path B can be adjusted independently for each of the plurality of first exhaust ports 41b, and the length of each of the plurality of exhaust paths B can be made more reliably consistent. According to this embodiment, the velocity of the process gas flowing horizontally from the plurality of gas supply ports 31 toward the first exhaust port 41 can be made more reliably consistent among the plurality of gas supply ports 31, i.e., among the plurality of wafers 200. As a result, the thickness of the SiN film formed on the wafer 200 can be made more reliably consistent among the wafers 200.

[0105] (e) In this embodiment, a third fin 500 is also provided, oriented in a direction different from the direction along the outer periphery of the sidewall of the inner tube 21. Furthermore, the end of the third fin 500 extends to a position where it collides with the processing gas flowing horizontally at the ends of the first fin 300 and the second fin 400. This allows the exhaust gas discharged from the plurality of first exhaust ports 41 (first exhaust port 41a and plurality of first exhaust ports 41b) to rapidly change its path towards the second exhaust port 91 after passing through the first fin 300 and the second fin 400 a predetermined distance in the horizontal direction. According to this embodiment, the length of exhaust path A and the lengths of the plurality of exhaust paths B can be controlled in a way that keeps them stable. Moreover, the lengths of exhaust path A and the plurality of exhaust paths B can be made more reliably consistent. As a result, the thickness of the SiN film formed on the wafer 200 can be made more reliably consistent between the wafers 200.

[0106] (f) In this embodiment, the third fin 500 is positioned at a predetermined distance from both ends of the first fin 300 and the second fin 400 along the outer periphery of the sidewall of the inner tube 21. Specifically, the distance D1 between the end of the first fin 300 along the outer periphery of the sidewall of the inner tube 21 and the third fin 500 is larger than the distance D2 between the first fin 300 and the second fin 400 adjacent to the first fin 300 along the aforementioned arrangement direction (here, the vertical direction). In this way, by appropriately ensuring the gaps between the multiple fins, local stagnation of exhaust gas in the exhaust buffer space can be avoided, such as the concentration of exhaust gas between the first fin 300 and the third fin 500, and the resulting stagnation of exhaust gas. As a result, uniform pressure adjustment can be achieved throughout the entire area of ​​the processing chamber 23, and consequently, the film thickness of the SiN film formed on the wafers 200 can be made more reliably consistent between the wafers 200.

[0107] (g) In this method, by providing the third fin 500, the exhaust gas is less likely to come into contact with the temperature sensor 11 located along the outer wall of the inner tube 21, thereby enabling accurate temperature detection throughout the entire area of ​​the substrate storage region 65. As a result, the quality of substrate processing can be improved.

[0108] <Another way of this disclosure>

[0109] The above describes one method of this disclosure, but this disclosure is not limited to the above method and various changes can be made without departing from its main purpose.

[0110] For example, in the above description, the second fin 400 and the third fin 500 are also disposed within the exhaust buffer space in addition to the first fin 300, but this disclosure is not limited to this. For example, either or both of the second fin 400 and the third fin 500 may be omitted from the exhaust buffer space. In these cases, at least some of the effects described in the above description can still be obtained.

[0111] Furthermore, for example, the above description illustrates an example where all three fins—the first fin 300, the second fin 400, and the third fin 500—are disposed on the outer wall of the inner tube 21, but this disclosure is not limited to this. For instance, any one or all of the first fin 300, the second fin 400, and the third fin 500 may be disposed on the inner wall of the outer tube 22. In these cases, the same effect as described above can also be obtained.

[0112] Furthermore, for example, in the above description, an example was given in which the second fin 400 is respectively disposed in each of the plurality of first exhaust ports 41b, but this disclosure is not limited thereto. For example, the second fin 400 may be disposed at intervals of several (e.g., 2 to 5 intervals) relative to the plurality of first exhaust ports 41b. In this case, the same effect as described above can also be obtained.

[0113] Furthermore, for example, the above description illustrates an example where the third fin 500 is inclined relative to the arrangement direction (vertical direction), but this disclosure is not limited to this. For example, the third fin 500 may also be arranged parallel to the arrangement direction (vertical direction). Furthermore, the shape of the third fin 500 is not limited to being straight; it may also be curved. In these cases, the same effect as described above can be obtained.

[0114] Furthermore, for example, in the above description, an example was given where each of the plurality of first exhaust ports 41 is positioned opposite the gas supply port 31 in the substrate receiving area 65, which is separated from the sidewall of the inner tube 21. However, this disclosure is not limited to this. For example, the first exhaust ports 41 may be positioned so that they are offset circumferentially from the positions on the sidewall of the inner tube 21 opposite the gas supply port 31, separated from the substrate receiving area 65. In these cases, the same effect as described above can also be obtained.

[0115] Furthermore, for example, the above description illustrates an example of providing a gas supply port 31 and a first exhaust port 41 for each of the plurality of wafers 200 housed within the substrate housing region 65, but this disclosure is not limited to this. For example, at least one of the gas supply port 31 and the first exhaust port 41 may be provided every few wafers (e.g., every 2 to 5 wafers) relative to the plurality of wafers 200 housed within the substrate housing region 65. In these cases, the same effect as described above can also be obtained.

[0116] Furthermore, while the above description illustrates the formation of a SiN film on wafer 200, this disclosure is not limited to this. For example, this disclosure can also be appropriately applied when forming silicon films (Si films), silicon oxide films (SiO films), silicon oxynitride films (SiON films), etc., on wafer 200. Additionally, this disclosure can also be appropriately applied when forming metallic thin films such as titanium films (Ti films), titanium oxide films (TiO films), titanium nitride films (TiN films), aluminum films (Al films), aluminum oxide films (AlO films), and hafnium oxide films (HfO films) on wafer 200. In these cases, the same effects as described above can be obtained.

[0117] This disclosure is not limited to the process of forming films on multiple wafers 200 respectively. It can also be appropriately applied when each of the multiple wafers 200 is etched, annealed, or subjected to plasma modification. In these cases, the same effect as described above can be obtained.

[0118] Symbol Explanation

[0119] 21—Inner tube; 22—Outer tube; 31, 31a, 31b—Gas supply port; 41, 41a, 41b—First exhaust port; 65—Substrate storage area; 91—Second exhaust port; 200—Wafer (substrate); 300—First fin; 400—Second fin; 500—Third fin; R—Rectifying mechanism.

Claims

1. A substrate processing apparatus, characterized in that, have: The inner tube has a substrate storage area inside which multiple substrates are arranged in a horizontal posture along a predetermined arrangement direction to form multiple layers and are stored therein. An outer tube, which is disposed on the outside of the inner tube; Gas supply ports are provided in multiple locations along the arrangement direction on the side wall of the inner tube; The first exhaust port has multiple outlets arranged along the arrangement direction on the side wall of the inner tube; A second exhaust port is disposed at one end of the outer pipe along the arrangement direction; and A rectifier mechanism controls the gas flow within the annular space between the inner and outer tubes. The rectifier has a first fin near the first exhaust port closest to the second exhaust port among a plurality of first exhaust ports, namely exhaust port A between exhaust port A and the second exhaust port, and also has a second fin near the first exhaust port B, which is different from exhaust port A, between exhaust port B and the second exhaust port. The second fin is arranged along the outer periphery of the side wall of the inner tube with a predetermined length larger than the inner diameter of exhaust port B in the horizontal direction, and its length is shorter than the length of the first fin.

2. The substrate processing apparatus according to claim 1, characterized in that, The first fin is arranged along the outer periphery of the side wall of the inner tube at a predetermined length larger than the inner diameter in the horizontal direction of the exhaust port A.

3. The substrate processing apparatus according to claim 1, characterized in that, The rectifier has a plurality of second fins along the arrangement direction.

4. The substrate processing apparatus according to claim 3, characterized in that, The length of the multiple second fins gradually decreases as the distance from the second exhaust port increases.

5. The substrate processing apparatus according to claim 1, characterized in that, The device has a plurality of exhaust ports B, and the rectifier mechanism provides the second fin for each of the plurality of exhaust ports B.

6. The substrate processing apparatus according to claim 1, characterized in that, The first exhaust port is located on the side wall of the inner tube, opposite the gas supply port, across the substrate storage area.

7. The substrate processing apparatus according to claim 1, characterized in that, The first vent is provided for each substrate housed within the substrate housing area.

8. The substrate processing apparatus according to claim 1, characterized in that, The rectifier also includes a third fin, which is configured to face a direction different from the direction along the outer periphery of the sidewall of the inner tube.

9. The substrate processing apparatus according to claim 8, characterized in that, The end of the third fin extends to the position where the gas flowing horizontally at the end of the first fin collides with the gas, such that the gas flowing horizontally at the end of the first fin is directed toward the second exhaust port.

10. The substrate processing apparatus according to claim 8, characterized in that, The distance (D1) between the end of the first fin and the third fin along the outer periphery of the sidewall of the inner tube is greater than the distance (D2) between the first fin and the second fin adjacent to the first fin along the arrangement direction.

11. The substrate processing apparatus according to claim 8, characterized in that, The plurality of third fins are respectively disposed at a predetermined distance from both ends of the first fin along the outer periphery of the inner tube sidewall.

12. A method for manufacturing a semiconductor device, characterized in that, have: The process of arranging multiple substrates horizontally in a predetermined arrangement direction into multiple layers and storing them in a substrate storage area inside an inner tube. The process of supplying gas into the inner tube from multiple gas supply ports arranged along the arrangement direction on the side wall of the inner tube; The process of discharging gas supplied to the inner tube from a plurality of first exhaust ports arranged along the arrangement direction on the side wall of the inner tube into an outer tube arranged on the outside of the inner tube; The process of venting air from a second exhaust port located at one end of the outer tube along the arrangement direction into the annular space between the inner tube and the outer tube; and The process of controlling the gas flow in the annular space using a rectifier mechanism having a first fin and a second fin, wherein the rectifier mechanism has the first fin near the first exhaust port closest to the second exhaust port among a plurality of first exhaust ports, i.e., exhaust port A between the second exhaust port and the second exhaust port, and has the second fin near the first exhaust port B, i.e., exhaust port B different from the exhaust port A, between the second exhaust port and the second exhaust port. The second fin is provided along the outer periphery of the side wall of the inner tube with a predetermined length larger than the inner diameter in the horizontal direction of the exhaust port B, and its length is shorter than the length of the first fin.

13. A storage medium that can be read by a computer, characterized in that, It stores a program that causes the computer to perform the following steps: The step of arranging multiple substrates horizontally in a predetermined arrangement direction into multiple layers and storing them in a substrate storage area inside an inner tube. The step of supplying gas into the inner tube from a plurality of gas supply ports arranged along the arrangement direction on the side wall of the inner tube; The step of discharging gas supplied to the inner tube from a plurality of first exhaust ports arranged along the arrangement direction on the side wall of the inner tube into an outer tube arranged on the outside of the inner tube; The step of venting air from a second exhaust port located at one end of the outer tube along the arrangement direction into the annular space between the inner tube and the outer tube; as well as The step of controlling the gas flow in the annular space using a rectifier mechanism having a first fin and a second fin, wherein the rectifier mechanism has the first fin near the first exhaust port closest to the second exhaust port among a plurality of first exhaust ports, i.e., exhaust port A between the second exhaust port and the second exhaust port, and has the second fin near the first exhaust port B, i.e., exhaust port B different from the exhaust port A, between the second exhaust port and the second exhaust port. The second fin is provided along the outer periphery of the side wall of the inner tube with a predetermined length larger than the inner diameter in the horizontal direction of the exhaust port B, and its length is shorter than the length of the first fin.

14. An inner tube having an internal substrate storage area for arranging and storing multiple substrates in a horizontal orientation along a predetermined arrangement direction, and disposed within an outer tube having a second vent at one end along the arrangement direction. The inner tube is characterized in that, Multiple gas supply ports are provided on the side wall of the inner tube along the arrangement direction. The inner tube has multiple first exhaust ports arranged along the arrangement direction on its side wall. On the sidewall of the inner tube, a first fin is provided near the first exhaust port closest to the second exhaust port among a plurality of first exhaust ports, i.e., exhaust port A between the second exhaust port and the first exhaust port. The first fin constitutes at least part of a flow-rectifying mechanism for controlling the gas flow in the annular space between the inner tube and the outer tube. A second fin is provided near the exhaust port B between the first exhaust port B, which is different from the exhaust port A, and the second exhaust port. The second fin is provided along the outer periphery of the sidewall of the inner tube with a predetermined length larger than the inner diameter of the exhaust port B in the horizontal direction, and its length is shorter than the length of the first fin.

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