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

Abstract

To provide a substrate processing device, a manufacturing method for a semiconductor device, a substrate processing method, and a program to shorten the cooling time of an insulation part.SOLUTION: The substrate processing device includes a processing chamber 21 for processing a substrate, a lid that closes a lower opening of the processing chamber, an elevator for moving the lid up and down, a heat insulating part 33 that is installed between the lid and the substrate and has a cylindrical part formed in the shape of a tube with a closed upper end, and a cooling gas supply part 44 that supplies purge gas from a discharge port in the cylindrical part to purge the inside of the insulation part while the lid is closing the opening and supplies cooling gas from the discharge port when the lid is not blocking the opening to cool the insulation part.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In some semiconductor device manufacturing methods, vertical substrate processing apparatuses are used to process substrates. Also, there are substrate processing apparatuses that include a boat for holding substrates and processing chambers for processing the substrates, and the boat is sequentially loaded and unloaded from each processing chamber to process the substrates.

[0003] The boat has a cylindrical heat insulating section at the bottom to maintain the temperature inside the processing chamber. During the substrate cooling process, cooling gas is sometimes sprayed onto the boat to cool the substrate and the heat insulating section. Because the heat insulating section has a larger heat capacity than the substrate, the cooling time during the cooling process must be set to match the cooling time of the heat insulating section. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-49853 Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure provides a technique that enables the cooling time of a heat insulating portion to be shortened. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, there is provided a technology comprising: a processing vessel for processing a substrate; a lid for closing a lower opening of the processing vessel; an elevator for moving the lid up and down; an insulating section installed between the lid and the substrate and having a cylindrical section formed in a cylindrical shape with a closed upper end; and a cooling gas supply section for supplying a purge gas from an outlet in the cylindrical section when the lid is closing the opening to purge the inside of the insulating section, and supplying a cooling gas from the outlet when the lid is not closing the opening to cool the insulating section. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to reduce the cooling time of the heat insulating section. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view illustrating an example of a substrate processing apparatus according to an embodiment of the present disclosure. [Figure 2] FIG. 1 is a vertical cross-sectional view illustrating an example of a processing furnace according to an embodiment of the present disclosure. [Figure 3] FIG. 2 is a longitudinal cross-sectional view illustrating an example of a heat insulating section according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is a block diagram illustrating a control system of a controller of the substrate processing apparatus according to an embodiment of the present disclosure. [Figure 5] 1 is a flowchart illustrating a substrate processing method according to an embodiment of the present disclosure. [Figure 6] FIG. 10 is a perspective view illustrating a modified example of a supply pipe according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, one embodiment of the present disclosure will be described mainly with reference to Figures 1 to 5. Note that all drawings used in the following description are schematic, and the dimensional relationships between elements, the ratios of elements, etc. shown in the drawings do not necessarily correspond to the actual ones. Furthermore, the dimensional relationships between elements, the ratios of elements, etc. do not necessarily correspond between multiple drawings. Note that the same or corresponding components in all drawings are denoted by the same or corresponding reference numerals, and redundant explanations will be omitted.

[0010] In this embodiment, the substrate processing apparatus is configured as a vertical substrate processing apparatus (hereinafter referred to as the substrate processing apparatus) 1 that performs substrate processing processes such as heat treatment as one step in a manufacturing method for a semiconductor device.

[0011] 1, the substrate processing apparatus 1 includes a processing module 2, which has a housing or body having an outline of a roughly rectangular parallelepiped. The processing module 2 is composed of a processing furnace 4 and a transfer chamber 5.

[0012] A transfer chamber 5 is disposed below the processing furnace 4, and a transfer chamber 11 is disposed adjacent to the front side of the transfer chamber 5. The transfer chamber 11 has a roughly rectangular parallelepiped outer casing and is equipped with a transfer machine 9 for transferring wafers 8 as substrates. A storage chamber 13 is connected to the front side of the transfer chamber 11, and stores pods (FOUPs) 12 that store multiple wafers 8. The storage chamber 13, processing module 2, and transfer chamber 11 each have a polyhedral outer shape composed of mutually orthogonal faces, and are detachably configured, with their connections having appropriate airtightness. An I / O port 14 is disposed in front of the storage chamber 13, and pods 12 are loaded and unloaded into and from the substrate processing apparatus 1 via the I / O port 14. A loading table 16 is disposed adjacent to the transfer chamber 11, and wafers 8 are transferred from the pods 12 placed on the loading table 16.

[0013] A gate valve 15 is installed on the boundary wall (adjacent surface) between the transfer chamber 5 and the transfer chamber 11 to allow substrates to be loaded between them. Pressure detectors are installed in the transfer chamber 11 and the transfer chamber 5, respectively, and the pressure within the transfer chamber 11 is set to be lower than the pressure within the transfer chamber 5. Oxygen concentration detectors are also installed in the transfer chamber 11 and the transfer chamber 5, respectively, and the oxygen concentrations within the transfer chamber 11 and the transfer chamber 5 are maintained lower than the oxygen concentration in the atmosphere. A clean unit 17 is installed on the ceiling of the transfer chamber 11 to supply clean air into the transfer chamber 11, and is configured to circulate, for example, an inert gas as the clean air within the transfer chamber 11. By circulating and purging the transfer chamber 11 with an inert gas, the transfer chamber 11 can be kept clean. This configuration makes it possible to prevent particles and the like from the transport chamber 5 from entering the transfer chamber 11, and to prevent a natural oxide film from forming on the wafer 8 in the transfer chamber 11 and the transport chamber 5.

[0014] 2, the processing furnace 4 includes a cylindrical processing vessel 18 (reaction tube 18) and a heater 19 as a heating means (heating mechanism) installed on the outer periphery of the reaction tube 18. The reaction tube 18 is formed of, for example, quartz (SiO2) or silicon carbide (SiC). A processing chamber 21 is formed inside the reaction tube 18 to process wafers 8 as substrates. In addition, a temperature detector 22 as a temperature detector is installed in the reaction tube 18 along the inner wall thereof.

[0015] Gases used for substrate processing are supplied into the processing chamber 21 by a gas supply mechanism 23 serving as a gas supply system. The gases supplied by the gas supply mechanism 23 are changed depending on the type of film to be formed. Here, the gas supply mechanism 23 includes a source gas supply unit, a reactive gas supply unit, and an inert gas supply unit. The gas supply mechanism 23 is housed in a supply box 24 (gas box 24) described below.

[0016] The source gas supply unit includes a gas supply pipe 25a, which is provided with, in order from the upstream direction, a mass flow controller (MFC) 26a, which is a flow rate controller (flow rate control unit), and a valve 28a, which is an on-off valve. The gas supply pipe 25a is connected to a nozzle 29a which penetrates a side wall of a manifold 27. The nozzle 29a is erected in the vertical direction within the reaction tube 18, and has a plurality of supply holes which open toward the wafers 8 held in a boat 31, which serves as a substrate holder. The source gas is supplied to the wafers 8 through the supply holes of the nozzle 29a.

[0017] In the following, with a similar configuration, reactive gas is supplied to wafer 8 from the reactive gas supply unit via gas supply pipe 25b, MFC 26b, valve 28b, and nozzle 29b. Inert gas is supplied to wafer 8 from the inert gas supply unit via gas supply pipes 25c and 25d, MFCs 26c and 26d, valves 28c and 28d, and nozzles 29a and 29b. Note that gas supply pipes 25a to 25d are collectively referred to as gas supply pipe 25, MFCs 26a to 26d are collectively referred to as MFC 26, valves 28a to 28d are collectively referred to as valve 28, and nozzles 29a and 29b are collectively referred to as nozzle 29.

[0018] A cylindrical manifold 27 is connected to the lower opening of the reaction tube 18 via a sealing member such as an O-ring, and supports the lower end of the reaction tube 18. The lower opening of the manifold 27 is disposed corresponding to the ceiling of the transfer chamber 5, and the lower opening communicates with the transfer chamber 5 and is opened and closed by a disk-shaped lid 32. A sealing member such as an O-ring is installed on the upper surface of the lid 32, thereby airtightly sealing the reaction tube 18 from the outside air. An insulating member 33 is placed on the lid 32. The reaction tube 18 and the manifold 27 are collectively referred to as the reaction tube (processing vessel) 18. In this case, the lower opening of the reaction tube 18 is closed by the lid 32.

[0019] The manifold 27 has an exhaust port 30 extending perpendicular to the axis, i.e., perpendicular to the axis of the reaction tube 18. An exhaust pipe 34 is attached via the exhaust port 30. The exhaust pipe 34 is connected to a booster pump 38, which serves as a vacuum exhaust device, via a pressure sensor 35 serving as a pressure detector (pressure detection unit) that detects the pressure inside the process chamber 21 and a conductance variable valve 36 serving as a pressure regulator (pressure adjustment unit). The conductance variable valve 36 is a two-stage valve consisting of two valves, an APC (Auto Pressure Controller) valve and a gate valve, connected in series. The APC valve is a butterfly valve that can open with a flow path cross-sectional area equal to or greater than the cross-sectional area of ​​the exhaust pipe 34. This configuration allows the pressure inside the process chamber 21 to be adjusted to a processing pressure appropriate for the process. An exhaust system 39 is mainly composed of the exhaust pipe 34, the pressure sensor 35, and the conductance variable valve 36. The booster pump 38 may be included in the exhaust system 39.

[0020] The processing chamber 21 accommodates a boat 31 serving as a substrate holder for vertically supporting a plurality of wafers 8, e.g., 10 to 150 wafers 8, in a shelf-like fashion. The boat 31 is supported above the heat insulating section 33 by a rotation shaft 41 that penetrates the lid section 32 and the heat insulating section 33, and holds the wafers 8 within the reaction tube 18. The rotation shaft 41 is hollow and rotatably supported by a rotation mechanism 42 installed below the lid section 32. The rotation shaft 41 is configured to be rotatable while hermetically sealing the interior of the reaction tube 18. The lid section 32 is driven vertically by a boat elevator 43, which serves as an elevator mechanism (elevator) installed in the transfer chamber 5. As a result, the boat 31 and the lid section 32 are raised and lowered together, and the boat 31 is loaded into and unloaded from the reaction tube 18. The lowered boat 31 is accommodated in the transfer chamber 5, and the wafers 8 are transferred to and from the boat 31 in the transfer chamber 5.

[0021] The heat insulating section 33 is configured so that a cooling gas and a purge gas are introduced through a cooling gas supply section 44. The cooling gas supply section 44 includes an inlet 45, a supply pipe 46 connected to the inlet 45, a gas supply pipe 47a connected to the supply pipe 46, and a gas supply pipe 47b branching off from the gas supply pipe 47a.

[0022] Gas supply pipe 47a is provided with, in order from the upstream direction, a mass flow controller (MFC) 48a which is a flow rate controller (flow rate control section) and a valve 49a which is a control valve. Gas supply pipe 47b is provided with, in order from the upstream direction, a mass flow controller (MFC) 48b which is a flow rate controller (flow rate control section) and a valve 49b which is a control valve. Gas supply pipes 47a, 47b, MFCs 48a, 48b, and valves 49a, 49b are housed in gas box 24. Cooling gas supply unit 44 may be part of gas supply mechanism 23. Note that gas supply pipes 47a, 47b will also be referred to collectively as gas supply pipes 47, MFCs 48a, 48b will also be referred to collectively as MFC 48, and valves 49a, 49b will also be referred to collectively as valve 49.

[0023] The introduction section 45 has an introduction pipe 45a erected along the vertical direction of the rotation mechanism 42, and a port 45b formed on the side of the rotation mechanism 42 and connected to the introduction pipe 45a. Therefore, the introduction pipe 45a is fixedly provided with respect to the rotation mechanism 42, and is configured to move vertically together with the lid section 32 by the boat elevator 43. The introduction pipe 45a may also be fixedly provided to the lid section 32.

[0024] The introduction pipe 45a and the interior of the rotation mechanism 42 are in communication with each other via the port 45b, and the rotation mechanism 42 is in communication with the interior of the heat insulating unit 33 via a hole 45c that passes through the rotation shaft in the vertical direction. The introduction section 45 is formed by the introduction pipe 45a, the port 45b, the space between the interior of the rotation mechanism 42 and the rotation shaft 41, and the hole 45c that passes through the rotation shaft 41, so that the rotation shaft 41 constitutes a part of the introduction section 45. Therefore, the interior of the rotation shaft 41 (hole 45c) is in fluid communication with the interior of the heat insulating unit 33, and the heat insulating unit 33 is in fluid communication with the interior of the rotation mechanism 42 via the hole 45c.

[0025] The supply pipe 46 is made of, for example, a synthetic resin containing fluorine and is flexible. The supply pipe 46 has a predetermined length and is connected to the inlet pipe 45a and the gas supply pipe 47a in a bent state. The supply pipe 46 has a length that allows it to maintain a connection with the inlet pipe 45a and the gas supply pipe 47a regardless of the position of the boat 31. Therefore, even if the inlet 45 moves up and down together with the boat 31, fluid communication is maintained between the inlet 45, the supply pipe 46, and the gas supply pipe 47a. In this case, the end of the supply pipe 46 on the gas supply pipe 47a side (upstream side) is a fixed end that does not move, and the end on the inlet pipe 45a side (downstream side) is a moving end that moves up and down together with the boat 31.

[0026] The gas supply pipe 47a is connected to a cooling gas supply source, and supplies cooling gas into the heat insulating section 33 via the gas supply pipe 47a, the supply pipe 46, and the introduction section 45. The gas supply pipe 47b is connected to a purge gas supply source, and supplies purge gas into the heat insulating section 33 via the gas supply pipe 47b, the gas supply pipe 47a, the supply pipe 46, and the introduction section 45. Therefore, by opening and closing the valves 49a and 49b as control valves, it is possible to turn on and off the supply of the cooling gas and the purge gas, that is, to switch between supply and stop, and also to selectively supply the cooling gas and the purge gas into the heat insulating section 33.

[0027] As the cooling gas, for example, industrial nitrogen gas or air (artificial air) at room temperature can be used. Furthermore, pure nitrogen gas for semiconductor processes or ordinary nitrogen gas can be used as the purge gas. Therefore, since gas heating or cooling is not required, it can be applied inexpensively. Industrial nitrogen gas can be prepared by vaporizing industrial liquefied nitrogen, and such gas can also be used as a purge gas due to its high purity.

[0028] The introduction pipe 45a may be configured as a part of the supply pipe 46. In this case, the supply pipe 46 is a flexible part having flexibility, and the introduction pipe 45a is a non-flexible part having no flexibility for connecting the moving end of the supply pipe 46 and the rotation mechanism 42.

[0029] A controller 51 (described later) that controls the rotation mechanism 42, boat elevator 43, MFCs 26a to 26d of the gas supply mechanism 23, valves 28a to 28d, conductance variable valve 36, and MFCs 48a and 48b and valves 49a and 49b of the cooling gas supply unit 44 is connected to these components. The controller 51 has, for example, a microprocessor (computer) equipped with a CPU, and is configured to control the operation of the processing module 2.

[0030] The heat insulating unit 33 and the rotation mechanism 42 will be described in detail with reference to Figure 4. The rotation mechanism 42 includes a casing 53 formed in a generally cylindrical shape with an open upper end and a closed lower end, and the casing 53 is disposed on the underside of the lid unit 32. An elongated cylindrical inner shaft 54 ​​is disposed inside the casing 53. An outer shaft 55 formed in a cylindrical shape with a larger diameter than the outer diameter of the inner shaft 54 ​​is disposed inside the casing 53, and the outer shaft 55 is rotatably supported by a pair of upper and lower inner bearings 56a, 56b interposed between the outer shaft 55 and the inner shaft 54, and a pair of upper and lower outer bearings 57a, 57b interposed between the outer shaft 55 and the casing 53.

[0031] The inner bearing 56a and the outer bearing 57a are respectively provided with magnetic fluid seals 58a, 58b as sealing parts. A cap 59 that seals the lower end of the outer shaft 55 is fixed to the underside of the closed wall of the casing 53. The magnetic fluid seals 58a, 58b maintain airtightness between the rotating shaft 41 and the lid part 32, and the magnetic fluid seals 58a, 58b and the cap 59 give the casing 53 a sealed structure. A worm wheel 61 is fixed between the outer bearing 57a and the outer bearing 57b on the outer periphery of the outer shaft 55. A worm shaft 63 that is rotated by an electric motor 62 is engaged with the worm wheel 61.

[0032] A port 45b is formed on the processing chamber 21 side of the magnetic fluid seals 58a, 58b of the casing 53. Therefore, a space 45d between the casing 53 and the rotating shaft 41 communicates with the introduction pipe 45a via the port 45b on the processing chamber 21 side of the magnetic fluid seals 58a, 58b. Also, the space 45d communicates with the inside of the heat insulating part 33 via a hole 45c formed in the rotating shaft 41.

[0033] A sub-heater 64, which is a heater serving as a second heating means (heating mechanism) for heating the wafers 8 from below within the processing chamber 21, is inserted vertically inside the inner shaft 54. The sub-heater 64 includes a vertically extending support column 65 and a heat generating section 66 connected horizontally to the support column 65. The support column 65 is supported at the upper end of the inner shaft 54 ​​by a support column 68 made of heat-resistant resin. The lower end of the support column 67 is supported by the support column 68, which serves as a vacuum joint, via an O-ring, at a position below the lower surface of the closing wall of the casing 53.

[0034] The heating part 66 is formed in a generally annular shape with a diameter smaller than the outer diameter of the wafer 8, and is connected and supported by support parts 65 so as to be parallel to the wafer 8. A heater wire constituting a heating element 69, which is a coil-shaped resistance heating element, is enclosed inside the heating part 66. The heating element 69 is made of, for example, an Fe-Cr-Al alloy, molybdenum disilicide, or the like.

[0035] A cylindrical rotating shaft 41 having a flange at its lower end is fixed to the upper surface of the outer shaft 55. A through-hole is formed in the center of the rotating shaft 41, through which the sub-heater 64 passes. A disk-shaped receiving portion 71, which has a through-hole formed in its center for passing the sub-heater 64, is fixed to the upper end of the rotating shaft 41 with a predetermined distance h1 from the lid portion. h1 is preferably set to 2 to 10 mm. If h1 is less than 2 mm, components may come into contact with each other during boat rotation, or the gas exhaust speed within the cylindrical portion 70, which is a tubular portion described below, may decrease due to a decrease in conductance. If h1 is greater than 10 mm, a large amount of processing gas may enter the cylindrical portion 70.

[0036] The receiving portion 71 is formed of a metal such as stainless steel. A holding portion 73, which serves as an insulator holder for holding the insulator 72, and the cylindrical portion 70 are placed on the upper surface of the receiving portion 71. The receiving portion 71, the holding portion 73, the cylindrical portion 70, and the insulator 72 constitute the insulator 33. The cylindrical portion 70 is formed in a cylindrical shape with a closed upper end so as to house the sub-heater 64 therein. As shown in FIG. 3 , in a plan view, an exhaust hole 74 with a hole diameter h2 for exhausting the inside of the cylindrical portion 70 is formed in the area between the holding portion 73 and the cylindrical portion 70. The exhaust holes 74 are formed, for example, at equal intervals along a concentric circle of the receiving portion 71. It is preferable to set h2 to 10 to 40 mm. If h2 is less than 10 mm, the conductance may decrease, resulting in a decrease in the gas exhaust speed inside the cylindrical portion 70. If h2 is greater than 40 mm, the load-bearing strength of the receiving portion 71 may decrease, potentially resulting in damage.

[0037] 3, the holding part 73 is configured in a cylindrical shape having a through-hole 75 at its center through which the sub-heater 64 passes. The introduction pipe 45a is connected to a port 45b provided on the side surface of the casing 53, and the port 45b communicates with the penetrating light that passes through the lid part 32 (rotating shaft 41) and the receiving part 71, and opens to the through-hole 75 via the through-hole. In other words, the introduction part 45 and the through-hole 75 are in fluid communication.

[0038] The lower end of the holding portion 73 has an outward flange shape with an outer diameter smaller than that of the receiving portion 71. The upper end of the holding portion 73 is formed with a diameter larger than the diameter of the pillar portion between the upper and lower ends, and forms an outlet port 76 for the purge gas and the cooling gas. The diameter of the through hole 75 is configured to be larger than the diameter of the outer wall of the support portion 65 of the sub-heater 64. With this configuration, an annular space is formed between the holding portion 73 and the support portion 65, and this cylindrical space can be used as a first gas supply path that supplies the cooling gas and the purge gas into the heat insulating portion 33.

[0039] The holding portion 73 is made of a heat-resistant material such as quartz or SiC. The holding portion 73 is formed so that the connection surface between the flange at the lower end and the column is curved. This configuration prevents stress from concentrating on the connection surface, increasing the strength of the holding portion 73. Furthermore, by making the connection surface smooth, stagnation of the purge gas within the cylindrical portion 70 can be prevented without impeding the flow of the purge gas.

[0040] For example, a purge gas is supplied from the discharge port 76 toward the upper interior of the cylindrical portion 70. By forming the discharge port 76 as a circular opening, the purge gas can be uniformly supplied to the upper end of the cylindrical portion 70 and the entire circumferential direction of the circular plane. Furthermore, by making the diameter of the discharge port 76 larger than the diameter of the columnar portion, the purge gas can be supplied over a wide area toward the radial direction within the cylindrical portion 70 and toward the upper space within the cylindrical portion 70. In this way, by actively purging the cylindrical portion 70, particularly the vicinity of the upper end (ceiling portion) where the heat generating portion 66 is installed, with the purge gas, exposure of the process gas to the heat generating portion 66 can be suppressed. The purge gas supplied from the discharge port 76 is exhausted to the outside of the cylindrical portion 70 via a second flow path, which is the space between the holding portion 73 and the inner wall of the cylindrical portion 70.

[0041] A reflector plate 72A and a heat insulating plate 72B are installed on the pillars of the holding portion 73 as the heat insulator 72. The reflector plate 72A is fixedly held at the top of the holding portion 73, for example, by welding. The heat insulating plate 72B is fixedly held at the middle of the holding portion 73, for example, by welding. Retention shelves 77 are formed on the holding portion 73 above and below the heat insulating plate 72B, allowing additional heat insulating plates 72B to be held. The retention shelves 77 are configured to extend horizontally outward from the outer wall of the pillars of the holding portion 73. This configuration allows the heat insulating plates 72B to be held in multiple stages, horizontally aligned with their centers. A predetermined gap h3 is formed between the reflector plate 72A and the heat insulating plate 72B. It is preferable to set h3 to 50 to 300 mm.

[0042] The reflectors 72A are disk-shaped with a diameter smaller than that of the wafer 8, and are made of, for example, opaque quartz. They are held on an upper holding shelf 77 at a predetermined interval h4. h4 is preferably set to 2 to 10 mm. If h4 is smaller than 2 mm, gas may remain between the reflectors 72A. If h4 is larger than 10 mm, the heat reflection performance may be reduced.

[0043] The heat insulating plates 72B are disk-shaped with an outer diameter smaller than that of the wafers 8, and are preferably made of a material with low heat capacity and thermal conductivity, such as quartz, silicon (Si), or SiC. Here, four heat insulating plates 72B are held at a predetermined interval h5 on the lower holding shelf 77. h5 is preferably set to 2 mm or more. If h5 is smaller than 2 mm, gas may remain between the heat insulating plates 72B.

[0044] The number of reflecting plates 72A and insulating plates 72B held is not limited to the above numbers, and it is sufficient that the number of insulating plates 72B held is at least equal to or greater than the number of reflecting plates 72A. By placing reflecting plate 72A above and insulating plate 72B below in this manner, radiant heat from sub-heater 64 is reflected by reflecting plate 72A, and radiant heat from heater 19 and sub-heater 64 is insulated by insulating plate 72B at a location away from wafer 8, thereby improving the temperature responsiveness of wafer 8 and shortening the temperature rise time.

[0045] The boat 31 is placed on the upper surface of the cylindrical portion 70. A groove is formed around the entire outer periphery of the upper surface of the cylindrical portion 70, and the ring-shaped bottom plate of the boat 31 is placed in this groove. With this configuration, it becomes possible to rotate the cylindrical portion 70 and the boat 31 without rotating the sub-heater 64.

[0046] The upper end of the cylindrical portion 70 is formed in a convex shape. The inner periphery (inner wall) of the upper end of the cylindrical portion 70 is formed by a horizontal surface S1 that protrudes inward from the inner periphery of the side surface, an inclined surface S2 that is continuous with the horizontal surface S1, a vertical surface S3 that is continuous with the inclined surface S2 in the vertical direction, and a horizontal surface S4 that is continuous with the vertical surface S3. That is, the connecting portion (corner) between the convex horizontal surface S1 and the vertical surface S3 is tapered, and the cross-sectional area in a plan view gradually decreases toward the top of the cylindrical portion. Furthermore, the connecting portion between the vertical surface S3 and the horizontal surface S4 is formed into a curved surface. This configuration improves the flow of gas within the cylindrical portion 70 and prevents gas from accumulating in the convex portion. Furthermore, the purge gas supplied from the discharge port 76 collides with the inner wall of the upper surface of the cylindrical portion 70 and flows in the circumferential direction, and then flows from top to bottom along the side wall inside the cylindrical portion 70, making it easier to form a downflow of purge gas inside the cylindrical portion 70. In other words, a downflow can be formed in the second flow path. Furthermore, the horizontal surface S1 allows the thickness of the lower side of the boat mounting portion to be thicker than the thickness of the columnar portion of the cylindrical portion 70, thereby increasing the strength of the cylindrical portion 70.

[0047] The heat generating unit 66 is installed in the region between the upper end of the support 65 and the inner wall of the upper surface of the cylindrical unit 70, and is preferably installed so that at least a portion of the heat generating unit 66 is contained within the height position of the inclined surface S2. That is, the heat generating unit 66 is installed so that it is contained in the region in the height direction between the tangent point of the horizontal surface S1 and the inclined surface S2 and the tangent point of the inclined surface S2 and the vertical surface S3.

[0048] In the above description, for convenience, the cylindrical portion 70 is included in the heat insulating portion 33. However, since the area that is primarily insulated is the area below the sub-heater 64, i.e., the area of ​​the heat insulator 72, the heat insulator 72 can also be called the heat insulating portion. In this case, it can be said that the sub-heater 64 is provided between the boat 31 and the heat insulating portion.

[0049] As shown in FIG. 4 , the controller 51 is electrically connected to and automatically controls each of the components, such as the MFCs 26a-26d, 48a, and 48b, the valves 28a-28d, and 49a and 49b, the pressure sensor 35, the conductance variable valve 36, the booster pump 38, the heater 19, the sub-heater 64, the temperature detection unit 22, the rotation mechanism 42, and the boat elevator 43. The controller 51 is configured as a computer including a CPU (Central Processing Unit) 78, a RAM (Random Access Memory) 79, a storage device 81, and an I / O port 82. The RAM 79, the storage device 81, and the I / O port 82 are configured to be able to exchange data with the CPU 78 via an internal bus 83. The I / O port 82 is connected to each of the components described above. The controller 51 is connected to an input / output device 84, such as a touch panel.

[0050] The storage device 81 is configured with, for example, a flash memory, an HDD (Hard Disk Drive), etc. Control programs for controlling the operation of the substrate processing apparatus 1 and programs (recipes such as process recipes and cleaning recipes) for causing each component of the substrate processing apparatus 1 to perform a film formation process or the like according to processing conditions are readably stored in the storage device 81. The RAM 79 is configured as a memory area (work area) in which programs, data, etc. read by the CPU 78 are temporarily stored.

[0051] The CPU 78 reads out and executes a control program from the storage device 81, and also reads out a recipe from the storage device 81 in response to an input of an operation command from the input / output device 84, and controls each component in accordance with the recipe.

[0052] The controller 51 can be configured by installing the above-mentioned program, which is permanently stored in an external storage device (for example, a semiconductor memory such as a USB memory or a memory card, an optical disk such as a CD or a DVD, or a HDD) 85, into a computer. The storage device 81 and the external storage device 85 are configured as computer-readable tangible media. Hereinafter, these will be collectively referred to simply as recording media. Note that the program may be provided to the computer using a communication means such as the Internet or a dedicated line, without using the external storage device 85.

[0053] Next, a process (film formation process) for forming a film on a substrate using the above-described substrate processing apparatus 1 will be described with reference to the flowchart in Fig. 5. Here, an example will be described in which a silicon oxide (SiO2) film is formed on a wafer 8 by supplying DCS (SiH2Cl2: dichlorosilane) gas as a source gas and O2 (oxygen) gas as a reactive gas to the wafer 8. Note that in this specification, the process temperature refers to the temperature of the wafer 8 or the temperature of the process chamber 21, and the process pressure refers to the pressure inside the process chamber 21. In the following description, the operation of each component of the substrate processing apparatus 1 is controlled by a controller 51.

[0054] (Wafer charge and boat load) The gate valve 15 is opened, and the wafers 8 are transferred to the boat 31 (STEP: 01). When a plurality of wafers 8 are loaded into the boat 31 (wafer charge), the gate valve 15 is closed. The boat 31 is carried into the processing chamber 21 (boat load) by the boat elevator 43, and the lower opening of the reaction tube 18 is airtightly closed (sealed) by the lid 32 (STEP: 02).

[0055] (Pressure and temperature adjustment) The booster pump 38 evacuates (decompresses) the processing chamber 21 to a predetermined pressure (vacuum level). The atmosphere in the processing chamber 21 flows linearly or approximately linearly through the exhaust pipe 34 and is exhausted through the booster pump 38. The pressure in the processing chamber 21 is measured by the pressure sensor 35, and the conductance variable valve 36 is feedback-controlled based on this measured pressure information. Furthermore, the heater 19 heats the processing chamber 21 from the surroundings, and the sub-heater 64 heats the processing chamber 21 from below, so that the wafers 8 in the processing chamber 21 reach a predetermined temperature. Heating from both the surroundings and below allows the processing chamber 21 to be heated efficiently. At this time, the power supply to the heater 19 and the sub-heater 64 is feedback-controlled based on temperature information detected by the temperature detector 22 so that the processing chamber 21 achieves a predetermined temperature distribution. Furthermore, the rotation mechanism 42 starts to rotate the boat 31 and the wafers 8.

[0056] (film formation process) [Source gas supply process] When the temperature inside the processing chamber 21 stabilizes at a preset processing temperature, DCS gas is supplied to the wafers 8 inside the processing chamber 21. The DCS gas is controlled to a desired flow rate by the MFC 26a and supplied into the processing chamber 21 via the gas supply pipe 25a and the nozzle 29a. In parallel with the supply of DCS gas, i.e., with the lid 32 closing the opening of the reaction tube 18, the cooling gas supply unit 44 supplies purge gas, controlled to a desired flow rate by the MFC 48b, through the gas supply pipe 47b, the gas supply pipe 47a, the supply piping 46, the introduction unit 45, the through-hole 75, and the discharge port 76 into the heat insulating unit 33. The purge gas is sprayed directly onto the ceiling (the closed portion at the upper end) of the cylindrical unit 70, then diffuses circumferentially along the ceiling, descends along the circumferential surface, and is exhausted into the processing chamber 21 via the exhaust hole 74.

[0057] [Raw gas exhaust process] Next, the supply of DCS gas is stopped, and the inside of the processing chamber 21 is evacuated to a vacuum by the booster pump 38. The DCS gas in the processing chamber 21 flows linearly or approximately linearly through the exhaust pipe 34, and is exhausted via the booster pump 38. At this time, N2 gas may be supplied as an inert gas from the inert gas supply unit into the processing chamber 21 (inert gas purge).

[0058] [Reaction gas supply process] Next, O2 gas is supplied to the wafers 8 in the processing chamber 21. The O2 gas is controlled to a desired flow rate by the MFC 26b and is supplied into the processing chamber 21 via the gas supply pipe 25b and the nozzle 29b.

[0059] [Reaction gas exhaust process] Next, the supply of O2 gas is stopped, and the processing chamber 21 is evacuated to a vacuum using the booster pump 38. The O2 gas in the processing chamber 21 flows linearly or approximately linearly through the exhaust pipe 34 and is exhausted via the booster pump 38. At this time, N2 gas may be supplied as an inert gas from the inert gas supply unit into the processing chamber 21 (inert gas purge). Note that the supply of purge gas into the heat insulating unit 33 continues even during the source gas exhaust process, the reaction gas supply process, and the reaction gas exhaust process.

[0060] By repeating the cycle of the above four steps a predetermined number of times (one or more times), an SiO 2 film with a predetermined composition and a predetermined film thickness can be formed on the wafer 8 (STEP: 03).

[0061] (Boat unloading and wafer discharging) After forming a film of a predetermined thickness, N2 gas is supplied from the inert gas supply unit, the inside of the processing chamber 21 is replaced with N2 gas, and the pressure inside the processing chamber 21 is returned to normal pressure. Then, the boat elevator 43 lowers the lid 32, and the boat 31 is unloaded from the reaction tube 18 (boat unloading). Then, the processed wafers 8 are removed from the boat 31 (wafer discharge) (STEP: 04).

[0062] After the boat 31 is removed, i.e., while the lid 32 is not closing the opening of the reaction tube 18, a cooling process is performed on the wafers 8 and the heat insulating section 33 (STEP: 05). A cooling gas is supplied to the wafers 8 from a cooling gas supply mechanism (not shown). Concurrently with the cooling of the wafers 8, the cooling gas supply unit 44 supplies cooling gas, controlled to a desired flow rate by the MFC 48a, through the gas supply pipe 47a, the supply piping 46, the introduction section 45, the through-hole 75, and the discharge port 76 into the heat insulating section 33. The cooling gas is sprayed directly onto the closed section (ceiling) at the upper end of the cylindrical section 70, then diffuses circumferentially along the ceiling and descends along the circumferential surface, cooling the heat insulating body 72 and the cylindrical section 70, and is then exhausted into the transfer chamber 5 through the exhaust hole 74.

[0063] The cooling gas supplied into the heat insulating section 33 is, for example, N2 gas at room temperature, and has a flow rate equivalent to that of the purge gas. On the other hand, the flow rate of the cooling gas can be increased to the extent that it does not stir up particles in the transfer chamber 5. In this case, the mass flow rate of the cooling gas is greater than the mass flow rate of the purge gas.

[0064] When the wafers 8 and the heat insulating section 33 have been cooled to a predetermined temperature, the transfer machine 9 transfers the processed wafers 8 loaded in the boat 31 to the pod 12 (STEP: 06). The wafers 8 stored in the pod are then transported out of the substrate processing apparatus 1, and the film formation process is completed.

[0065] In the series of processes using the substrate processing apparatus 1 described above, if the substrate processing apparatus 1 is stopped in an emergency or if the maintenance door of the transfer chamber 5 is opened, the valves 49a and 49b may be interlocked to forcibly stop the supply of cooling gas or purge gas. In this case, the controller 51 functions as an interlock control unit. By forcibly stopping the supply of cooling gas or purge gas, leakage of gas to the outside of the substrate processing apparatus 1 and an increase in pressure in the processing chamber 21, etc. are prevented.

[0066] The processing conditions for forming an SiO2 film on the wafer 8 are, for example, as follows: Processing temperature (wafer temperature): 300℃~700℃ Processing pressure (pressure inside the processing chamber): 1 Pa to 4000 Pa, DCS gas: 100sccm to 10,000sccm, O2 gas: 100sccm~10000sccm, N2 gas: 100sccm to 10,000sccm, By setting each processing condition to a value within the respective range, the film formation process can be carried out appropriately. Note that the expression of a numerical range such as "1 Pa to 4000 Pa" above means that the lower limit and upper limit are included in the range. For example, "1 Pa to 4000 Pa" means "1 Pa or more and 4000 or less." The same applies to other numerical ranges.

[0067] According to this aspect, one or more of the following effects can be obtained.

[0068] In this embodiment, in the cooling process after forming a thin film on the wafer 8, cooling gas is supplied from the outlet 76 to the inside of the insulating section 33 via the inlet 45 and the through hole 75, and the cooling gas is circulated, making it possible to cool the insulating body 72 and the cylindrical section 70 from the inside.

[0069] Therefore, the cooling time of the heat insulating portion 33, which has a larger heat capacity than the wafer 8, can be reduced, thereby reducing the time required for the cooling process and the entire substrate processing process, and improving throughput.

[0070] Furthermore, the cooling gas is directly sprayed onto the closed portion at the upper end of the cylindrical portion 70, which is greatly affected by radiant heat from the processing chamber 21, thereby further improving the cooling efficiency of the heat insulating portion 33. Furthermore, the mass flow rate of the cooling gas can be made larger than the mass flow rate of the purge gas, thereby further improving the cooling efficiency of the heat insulating portion 33.

[0071] Furthermore, during the film formation process, i.e., while the boat 31 is loaded into the processing chamber 21, a purge gas is supplied into the heat insulating section 33 to purge the inside of the heat insulating section 33. This prevents the source gas and the reaction gas from flowing into the heat insulating section 33, and prevents a film from being formed on the heat insulator 72 or the sub-heater 64.

[0072] Furthermore, the supply pipe 46 is flexible, and in a bent state, the gas supply pipe 47a can be connected to the introduction pipe 45a fixed to the rotation mechanism 42 via the supply pipe 46. Therefore, the supply pipe 46 can move following the elevation of the boat 31, and therefore, fluid communication between the gas supply pipe 47a and the introduction part 45 can be ensured regardless of the position of the boat 31.

[0073] In this embodiment, the supply pipe 46 is made of a synthetic resin containing fluorine. However, the structure of the supply pipe 46 is not limited to this. For example, as in the modified example shown in Fig. 6, a supply pipe 88 having a portion that is flexible may be configured by alternately connecting inflexible metal pipes 86 and flexible metal bellows 87.

[0074] When the supply pipe 88 is used, the same effects as when the supply pipe 46 is used can be obtained, and durability can be improved compared to the supply pipe 46 .

[0075] Although the embodiments of the present disclosure have been specifically described above, the present disclosure is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit and scope of the present disclosure.

[0076] For example, in the above-described embodiment, an example in which DCS gas is used as the source gas has been described, but the present disclosure is not limited to such an embodiment. For example, as the source gas, in addition to DCS gas, inorganic halosilane source gases such as HCDS (SiCl: hexachlorodisilane) gas, MCS (SiHCl: monochlorosilane) gas, and TCS (SiHCl: trichlorosilane) gas, halogen-free amino (amine-based) silane source gases such as 3DMAS (Si[N(CH)]H: trisdimethylaminosilane) gas and BTBAS (SiH[NH(CH)]: bis(tertiarybutylaminosilane) gas, and halogen-free inorganic silane source gases such as MS (SiH: monosilane) gas and DS (SiH: disilane) gas can be used.

[0077] For example, in the above-described embodiments, an example of forming an SiO2 film has been described. However, the present disclosure is not limited to such an embodiment. For example, other than or in addition to these, a nitrogen (N)-containing gas (nitride gas) such as ammonia (NH3) gas, a carbon (C)-containing gas such as propylene (C3H6) gas, or a boron (B)-containing gas such as boron trichloride (BCl3) gas can be used to form a SiN film, SiON film, SiOCN film, SiOC film, SiCN film, SiBN film, SiBCN film, etc. When forming these films, the film formation can be performed under the same processing conditions as in the above-described embodiments, and the same effects as in the above-described embodiments can be obtained.

[0078] Furthermore, for example, the present disclosure can also be suitably applied to the case of forming a film containing a metal element such as titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), niobium (Nb), aluminum (Al), molybdenum (Mo), tungsten (W), or the like, i.e., a metal-based film, on a wafer 8.

[0079] In the above-described embodiment, an example has been described in which a film is deposited on the wafer 8. However, the present disclosure is not limited to such an embodiment. For example, the present disclosure can also be suitably applied to cases in which the wafer 8 or a film formed on the wafer 8 is subjected to an oxidation process, a diffusion process, an annealing process, an etching process, or the like.

[0080] The above-described embodiments and modifications may be used in combination as appropriate, and the processing conditions in this case may be the same as those in the above-described embodiments and modifications.

[0081] In the above-described embodiment, a film is formed using a substrate processing apparatus having a hot-wall type processing furnace. However, the aspects of the present disclosure can also be suitably applied to a case where a film is formed using a substrate processing apparatus having a cold-wall type processing furnace.

[0082] Even when a cold-wall type substrate processing apparatus is used, each process can be performed using the same process procedures and conditions as those of the above-mentioned embodiments and modifications, and the same effects as those of the above-mentioned embodiments and modifications can be obtained. [Explanation of symbols]

[0083] 1. Substrate processing equipment 8 wafers 18 Reaction tube 32 Lid 33 Insulation section 43 Boat Elevator 44 Cooling gas supply unit 76 Discharge port

Claims

1. a cooling gas supply unit that supplies a purge gas from an outlet in the cylindrical portion to purge the inside of the insulating unit when the lid is closing the opening, and supplies a cooling gas from the outlet to cool the insulating unit when the lid is not closing the opening.

2. 2. The substrate processing apparatus of claim 1, wherein the cooling gas supply unit comprises an inlet portion that penetrates the lid to introduce the purge gas and the cooling gas into the thermal insulation unit, a movable supply pipe that is fluidly connected to the inlet portion and supplies the purge gas to the inlet portion, and a control valve that turns the supply of the purge gas and the cooling gas on and off.

3. The substrate processing apparatus according to claim 2 , wherein at least a portion of the supply pipe is flexible.

4. 2. The substrate processing apparatus according to claim 1, wherein at least a part of the cooling gas supply unit is fixed to the lid and moves up and down together with the lid by the elevator.

5. The substrate processing apparatus of claim 1 , wherein the mass flow rate of the cooling gas is greater than the mass flow rate of the purge gas.

6. 2. The substrate processing apparatus according to claim 1, further comprising: a transport chamber communicating with the opening of the processing vessel, having the elevator disposed therein, and accommodating a lowered substrate holder; and an interlock control unit configured to forcibly stop the supply of the purge gas and the cooling gas when the substrate processing apparatus is stopped in an emergency or when a maintenance door of the transport chamber is opened.

7. 2. The substrate processing apparatus according to claim 1, wherein the purge gas is pure nitrogen gas, and the cooling gas is nitrogen gas having a purity lower than that of the pure nitrogen gas.

8. 2. The substrate processing apparatus according to claim 1, further comprising a substrate holder that can move up and down together with the lid to move in and out of the opening, and that holds the substrate within the processing vessel.

9. The substrate processing apparatus according to claim 1 , further comprising a heater disposed in the cylindrical portion for heating the inside of the processing vessel.

10. 2. The substrate processing apparatus according to claim 1, wherein the outlet is open so that the cooling gas directly hits a closed portion at the upper end of the cylindrical portion.

11. 3. The substrate processing apparatus of claim 2, further comprising: a hollow rotating shaft that supports the heat insulating section from below and constitutes at least a part of the introduction section; and a rotating mechanism that is provided on the lid and rotatably supports the rotating shaft, wherein the inside of the heat insulating section and the inside of the rotating shaft are fluidically connected.

12. 12. The substrate processing apparatus according to claim 11, wherein the rotation mechanism includes a casing having a sealed structure and a seal portion that maintains airtightness between the rotation shaft and the lid, and the supply pipe is connected to a port provided in the casing.

13. 13. The substrate processing apparatus according to claim 12, wherein the port is in communication with a space between the casing and the rotating shaft on the processing vessel side of the seal portion, and the rotating shaft has a hole that connects the outside to the inside of the rotating shaft.

14. The substrate processing apparatus of claim 11, wherein the supply pipe has a flexible portion having a fixed end on the upstream side that does not move and a movable end that moves up and down together with the lid by the elevator, and a non-flexible portion that connects the movable end to the rotation mechanism.

15. 4. The substrate processing apparatus according to claim 3, wherein the supply pipes are configured by alternately connecting flexible metal bellows and inflexible metal pipes.

16. 4. The substrate processing apparatus according to claim 3, wherein the supply pipe is made of a synthetic resin containing fluorine.

17. 3. The substrate processing apparatus according to claim 2, wherein the control valve is disposed in a gas box that houses a flow rate controller or a control valve for a processing gas for processing the substrate.

18. A method for manufacturing a semiconductor device, comprising: a step of supplying a purge gas from an outlet in a cylindrical portion of an insulating portion that is installed between a lid and a processing vessel for processing a substrate, the insulating portion having a cylindrical portion formed in a cylindrical shape with an upper end closed, while the lid is closing the lower opening of the processing vessel for processing the substrate, to purge the inside of the insulating portion; and a step of supplying a cooling gas from the outlet while the lid is not closing the opening, to cool the insulating portion.

19. A substrate processing method comprising the steps of: supplying a purge gas from an outlet in a cylindrical portion of an insulating portion that is installed between a lid and a processing vessel for processing a substrate and has a cylindrical portion formed in a cylindrical shape with an upper end closed, while the lid is closing a lower opening of the processing vessel for processing the substrate, to purge the inside of the insulating portion; and supplying a cooling gas from the outlet in a state where the lid is not closing the opening, to cool the insulating portion.

20. A program that causes a substrate processing apparatus to execute, by a computer, the following steps: when a lid is closing a lower opening of a processing vessel for processing a substrate, supplying a purge gas from an outlet in a thermal insulation section that is installed between the lid and the substrate and has a cylindrical portion formed in a cylindrical shape with a closed upper end, to purge the inside of the thermal insulation section; and when the lid is not closing the opening, supplying a cooling gas from the outlet to cool the thermal insulation section.

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