Substrate processing apparatus, furnace port assembly, substrate processing method, method for manufacturing semiconductor device, and recording medium

Abstract

The present invention relates to a substrate processing apparatus, a port assembly, a substrate processing method, a manufacturing method of a semiconductor device, and a recording medium, and can reduce corrosion of a port baffle. The present invention provides a substrate processing apparatus having a processing container provided with an opening through which a substrate holder holding a substrate is allowed to enter and exit and a first seal surface formed around the opening, and a port baffle provided with a second seal surface facing the first seal surface and capable of occluding the opening in a state where the substrate holder is not accommodated in the processing container; the port baffle has a protection plate arranged on an inner surface side facing the processing container and larger than the opening, and a cover arranged on an outer surface side and holding the protection plate, the second seal surface is formed from an outer peripheral portion of the protection plate and the cover, and a purge gas is supplied to a gap between the first seal surface and the second seal surface from a more outer peripheral side than the protection plate.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a substrate processing apparatus, a furnace port assembly, a substrate processing method, a manufacturing method of a semiconductor device, and a recording medium. BACKGROUND

[0002] As one of the processes of manufacturing a semiconductor device, for example, there is a thin film formation process of forming a thin film on a substrate such as a semiconductor wafer. The thin film formation process is performed by supplying a processing gas into a processing chamber after the substrate is carried in. The purpose of the thin film formation process is to form a thin film on the surface of the substrate, but in fact, a deposit including the thin film is sometimes attached to, for example, the inner wall of the processing chamber and the like, other than the surface of the substrate. This deposit is accumulated and attached every time the thin film formation process is performed, and if it reaches a certain thickness or more, it is peeled off from the inner wall of the processing chamber and the like, becoming a cause of generating foreign matter (particles) in the processing chamber. Therefore, every time the thickness of the deposit reaches a certain thickness, the inside of the processing chamber and the members inside the processing chamber need to be cleaned by removing the deposit. As a method of removing the deposit, a dry cleaning method of carrying an empty wafer boat into the processing chamber and supplying an etching gas (cleaning gas) to remove the deposit by dry etching is known.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT DOCUMENTS

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-185662 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] Sometimes, the wafer boat is not cleaned, and therefore, generally, cleaning is performed using a furnace port shutter that is closed for the purpose of heat retention in the furnace at the time of landing of the wafer boat and heat insulation of the transfer chamber. However, in the cleaning, since a gas having high metal corrosiveness is used, there is a case where the furnace port shutter is corroded.

[0008] An object of the present disclosure is to provide a technology capable of reducing corrosion of a furnace port shutter.

[0009] METHOD FOR SOLVING PROBLEMS

[0010] According to one embodiment of the present disclosure, there is provided a substrate processing apparatus including a processing container and a furnace port baffle. The processing container has an opening through which a substrate holder holding a substrate is allowed to enter and exit, and a first sealing surface formed around the opening. The furnace port baffle has a second sealing surface facing the first sealing surface and is capable of closing the opening in a state in which the substrate holder is not accommodated in the processing container. The furnace port baffle has a protection plate disposed on an inner surface side facing the processing container and larger than the opening, and a cover disposed on an outer surface side and holding the protection plate. The second sealing surface is formed by an outer peripheral portion of the protection plate and the cover. A purge gas is supplied to a gap between the first sealing surface and the second sealing surface from an outer peripheral side farther than the protection plate.

[0011] Effects of Invention

[0012] According to the present disclosure, it is possible to reduce corrosion of the furnace port baffle. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a schematic configuration view of a vertical processing furnace of a substrate processing apparatus suitable for use in one embodiment of the present disclosure, and is a view showing a portion of the processing furnace 202 in a longitudinal sectional view.

[0014] Figure 2 is a schematic configuration view of a vertical processing furnace of a substrate processing apparatus suitable for use in one embodiment of the present disclosure, and is a view showing a portion of the processing furnace 202 in a longitudinal sectional view. Figure 1 of the processing furnace 202 in a longitudinal sectional view.

[0015] Figure 3 is a schematic configuration view of a controller 121 of a substrate processing apparatus suitable for use in one embodiment of the present disclosure, and is a view showing a control system of the controller 121 in a block diagram.

[0016] Figure 4 is a schematic configuration view of a processing container of a substrate processing apparatus suitable for use in one embodiment of the present disclosure, and is a view showing a portion of a furnace port baffle 219s in a sectional view.

[0017] Figure 5 is a schematic configuration view of a furnace port baffle 219s of a substrate processing apparatus suitable for use in one embodiment of the present disclosure, and is a view showing a portion of the furnace port baffle 219s in a top perspective view.

[0018] Figure 6 is a schematic configuration view of a cooling water system of a substrate processing apparatus suitable for use in one embodiment of the present disclosure, and is a view showing a portion of the processing furnace 202 in a schematic view.

[0019] Figure 7 is a flowchart showing a manufacturing method of a semiconductor device in one embodiment of the present disclosure.

[0020] Symbol Explanation

[0021] 200··· wafer (substrate),

[0022] 217···Wafer Cell (Substrate Holder),

[0023] 219s··· Furnace opening baffle,

[0024] 219t··· Cover body,

[0025] 219w protection board. Detailed Implementation

[0026] The following description, regarding one aspect of this disclosure, will primarily refer to the accompanying drawings. It should be noted that the drawings used in the following description are schematic diagrams, and the dimensional relationships and ratios of the elements shown in the drawings need not be consistent with reality. Furthermore, the dimensional relationships and ratios of elements in multiple drawings need not be identical.

[0027] (1) Composition of substrate processing device

[0028] like Figure 1 As shown, the processing furnace 202 has a heater 207 that functions as a temperature regulator (heating unit). The heater 207 is cylindrical in shape and is vertically mounted, supported by a retaining plate. The heater 207 also functions as an activation mechanism (activation unit) that uses heat to activate (excite) the gas.

[0029] Inside the heater 207, a reaction tube 203 is arranged concentrically with the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed into a cylindrical shape with a closed upper end and an open lower end. Below the reaction tube 203, a manifold 209 is arranged concentrically with the reaction tube 203. The manifold 209 is made of a metal material such as stainless steel (SUS) and is formed into a cylindrical shape with open upper and lower ends. The upper end of the manifold 209 is connected to the lower end of the reaction tube 203 to support the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a sealing member. The reaction tube 203 is installed vertically, just like the heater 207. The processing container (reaction container) is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed in the hollow part of the cylindrical part of the processing container. The processing chamber 201 is configured to accommodate the wafer 200, which serves as a substrate. The wafer 200 is processed within the processing chamber 201.

[0030] In the processing chamber 201, nozzles 249a to 249c as first to third supply portions are provided to penetrate the side wall of the header 209, respectively. The nozzles 249a to 249c can also be referred to as first to third nozzles, respectively. The nozzles 249a to 249c are composed of a heat-resistant material such as quartz or SiC, for example. The nozzles 249a to 249c are connected to the gas supply pipes 232a to 232c, respectively. The nozzles 249a to 249c are different nozzles from each other, and the nozzles 249a, 249b are provided adjacently.

[0031] In the gas supply pipes 232a to 232c, mass flow controllers (MFCs) 241a to 241c as flow controllers (flow control portions) and valves 243a to 243c as on-off valves are provided in this order from the upstream side of the gas flow. The gas supply pipes 232d, 232e are connected to the downstream side of the valve 243a of the gas supply pipe 232a, respectively. The gas supply pipes 232f, 232h are connected to the downstream side of the valve 243b of the gas supply pipe 232b, respectively. The gas supply pipe 232g is connected to the downstream side of the valve 243c of the gas supply pipe 232c. In the gas supply pipes 232d to 232h, MFCs 241d to 241h and valves 243d to 243h are provided in this order from the upstream side of the gas flow, respectively. The gas supply pipes 232a to 232h are composed of a metal material such as SUS, for example.

[0032] As Figure 2As shown, the nozzles 249a, 249b are respectively provided in a space in the form of a circular ring in a plan view between the inner wall of the reaction tube 203 and the wafer 200, and stand upward toward the upper side of the arrangement direction of the wafer 200 along the lower portion to the upper portion of the inner wall of the reaction tube 203. That is, the nozzles 249a, 249b are respectively provided along the wafer arrangement region in a region horizontally surrounding the wafer arrangement region on the side of the wafer arrangement region. The nozzle 249c is different from the nozzles 249a, 249b, and extends in the horizontal direction without standing upward. In a plan view, the nozzle 249b is arranged so as to oppose the exhaust port 231a in line with the center of the wafer 200 carried into the processing chamber 201. The nozzles 249b, 249c are arranged so as to sandwich a straight line L passing through the center of the nozzle 249a and the exhaust port 231a from both sides along the inner wall of the reaction tube 203 (the outer peripheral portion of the wafer 200). The straight line L is also a straight line passing through the center of the nozzle 249b and the wafer 200. Gas supply holes 250a to 250c are respectively provided on the side surfaces of the nozzles 249a to 249c. The gas supply holes 250a, 250b respectively open in a manner so as to oppose (face) the exhaust port 231a in a plan view, and the gas supply holes 250a, 250b are capable of supplying gas toward the wafer 200. The gas supply holes 250a, 250b are provided in a plurality from the lower portion to the upper portion of the reaction tube 203. The gas supply hole 250c is provided in the circumferential direction.

[0033] The reaction gas is supplied from the gas supply pipe 232a to the processing chamber 201 via the MFC 241a, the valve 243a, and the nozzle 249a.

[0034] The source gas is supplied from the gas supply pipe 232b to the processing chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b.

[0035] The cleaning gas is supplied from the gas supply pipe 232c to the processing chamber 201 via the MFC 241c, the valve 243c, and the nozzle 249c.

[0036] The cleaning gas is supplied from the gas supply pipe 232d to the processing chamber 201 via the MFC 241d, the valve 243d, the gas supply pipe 232a, and the nozzle 249a.

[0037] The non-active gas is supplied from the gas supply pipes 232e to 232g to the processing chamber 201 via the MFCs 241e to 241g, the valves 243e to 243g, the gas supply pipes 232a to 232c, and the nozzles 249a to 249c, respectively.

[0038] The silicon or nitrogen containing substance is supplied from the gas supply pipe 232h to the processing chamber 201 via the MFC 241h, the valve 243h, the gas supply pipe 232b, and the nozzle 249b.

[0039] The reaction gas supply system is mainly composed of the gas supply pipe 232a, the MFC 241a, and the valve 243a. The source gas supply system is mainly composed of the gas supply pipe 232b, the MFC 241b, and the valve 243b. The cleaning gas supply system is mainly composed of the gas supply pipe 232c, the MFC 241c, and the valve 243c. The cleaning gas supply system is mainly composed of the gas supply pipe 232d, the MFC 241d, and the valve 243d. The non-reactive gas supply system is mainly composed of the gas supply pipes 232e to 232g, the MFCs 241e to 241g, and the valves 243e to 243g. The silicon or nitrogen supply system is mainly composed of the gas supply pipe 232h, the MFC 241h, and the valve 243h.

[0040] Here, the source gas and the reaction gas function as a film formation gas, and therefore, the source gas supply system and the reaction gas supply system can be referred to as a film formation gas supply system.

[0041] Any one or all of the above-described gas supply systems can also be configured as an integrated gas supply system 248 integrated by the valves 243a to 243h, the MFCs 241a to 241h, and the like. The integrated gas supply system 248 is configured to be connected to each of the gas supply pipes 232a to 232h and to be controlled by the controller 121 described later to control the supply of the various gases into the gas supply pipes 232a to 232h, that is, the opening and closing of the valves 243a to 243h, the flow rate adjustment by the MFCs 241a to 241h, and the like. The integrated supply system 248 is configured as an integrated unit of a unitary type or a split type, and is configured to be able to be attached to and detached from the gas supply pipes 232a to 232h and the like as a unit, and to be able to perform maintenance, replacement, addition, and the like of the integrated supply system 248 as a unit.

[0042] Below the side wall of the reaction pipe 203, an exhaust port 231a for exhausting the atmosphere in the processing chamber 201 is provided. As shown in FIG. 1, the exhaust port 231a is connected to the exhaust pipe 231b, and the exhaust pipe 231b is connected to the exhaust system 231c. Figure 2As shown, the exhaust port 231a is provided at a position sandwiching the wafer 200 and opposing (facing) the nozzles 249a to 249c (gas supply holes 250a to 250c) in a plan view. The exhaust port 231a can be provided along the lower portion to the upper portion of the side wall of the reaction tube 203, that is, along the wafer arrangement region. The exhaust port 231a is connected to an exhaust pipe 231. The exhaust pipe 231 is connected to a vacuum pump 246 as a vacuum exhaust device via a pressure sensor 245 as a pressure detector (pressure detection portion) that detects the pressure in the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 as a pressure regulator (pressure regulation portion). The APC valve 244 is configured in such a manner that, by opening and closing the valve in a state in which the vacuum pump 246 is operating, vacuum exhaust and stop of vacuum exhaust can be performed in the processing chamber 201, and further, by adjusting the valve opening degree based on the pressure information detected by the pressure sensor 245 in a state in which the vacuum pump 246 is operating, the pressure in the processing chamber 201 can be regulated. The exhaust system is mainly composed of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. It is also conceivable to include the vacuum pump 246 in the exhaust system.

[0043] Below the header 209, a seal cap 219 as a furnace port cap that can airtightly occlude the lower end opening of the header 209 is provided. The seal cap 219 is composed of, for example, a metal material such as SUS and is formed in a disc shape. On the upper surface of the seal cap 219, an O-ring 220b as a sealing member that abuts against the lower end of the header 209 is provided. Below the seal cap 219, a rotation mechanism 267 that rotates the wafer cassette 217 described later is provided. A rotation shaft 255 of the rotation mechanism 267 penetrates the seal cap 219 and is connected to the wafer cassette 217. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the wafer cassette 217. The rotation mechanism 267 is configured to have a ring-shaped groove not shown, and a purge gas supplied via the ring-shaped groove is supplied to the periphery of the rotation shaft 255. Thereby, corrosion of the rotation shaft 255 by the processing gas in the processing chamber 201 can be suppressed. The seal cap 219 is configured to be raised and lowered in the vertical direction by a wafer cassette elevator 115 as a lifting mechanism provided outside the reaction tube 203. The wafer cassette elevator 115 is configured as a conveyance device (conveyance mechanism) that carries the wafer 200 into and out of the processing chamber 201 by raising and lowering the seal cap 219.

[0044] A furnace opening baffle 219s is provided below the manifold 209. After the sealing cap 219 is lowered and the wafer cassette 217 is removed from the processing chamber 201, the furnace opening baffle 219s serves as a furnace opening cover capable of airtightly sealing the lower opening of the manifold 209. The furnace opening baffle 219s is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220c is provided on the upper surface of the furnace opening baffle 219s as a sealing member that abuts against the lower end of the manifold 209. Furthermore, the opening and closing action (lifting, rotating, etc.) of the furnace opening baffle 219s is controlled by a baffle opening mechanism 115s. Unlike the sealing cap 219, the furnace opening baffle 219s does not require consideration of film-forming quality or mirror polishing to reduce particle size. The furnace opening baffle 219s will be described in detail later.

[0045] The wafer cassette 217, serving as a substrate support, is configured to support multiple wafers (e.g., 25 to 200) 200 in a horizontal orientation, aligned center-to-center, arranged in multiple segments in the vertical direction, i.e., with intervals between them. The wafer cassette 217 is made of heat-resistant materials such as quartz or SiC. At the bottom of the wafer cassette 217, heat-insulating plates 218 made of heat-resistant materials such as quartz or SiC are supported in multiple segments.

[0046] A temperature sensor 263, serving as a temperature detector, is installed inside the reaction tube 203. The energizing of the heater 207 is adjusted based on the temperature information detected by the temperature sensor 263, thereby achieving the desired temperature distribution within the processing chamber 201. The temperature sensor 263 is disposed along the inner wall of the reaction tube 203.

[0047] like Figure 3 As shown, the controller 121, serving as the control unit (control unit), is configured as a computer having a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, a storage device 121c, and an I / O interface 121d. The RAM 121b, storage device 121c, and I / O interface 121d are configured to exchange data with the CPU 121a via an internal bus 121e. The controller 121 is connected to an input / output device 122, such as a touch panel.

[0048] The storage device 121c is constituted by, for example, a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), or the like. In the storage device 121c, a control program for controlling the operation of the substrate processing apparatus, a process recipe in which a process, a condition, and the like of the substrate processing described later are recorded, and the like are stored and can be read out. The process recipe is a program that functions to combine each process in the substrate processing described later so as to be executed by the controller 121 and obtain a predetermined result. Hereinafter, the process recipe, the control program, and the like are simply referred to as a program. Further, the process recipe is simply referred to as a recipe. In the present specification, when the term "program" is used, only the recipe is included at times, only the control program is included at times, and both of them are included at times. The RAM 121b is constituted as a storage area (work area) in which the program, data, and the like read out by the CPU 121a are temporarily stored.

[0049] The I / O interface 121d is connected to the MFCs 241a to 241h, the valves 243a to 243h, the pressure sensor 245, the APC valve 244, the vacuum pump 246, the temperature sensor 263, the heater 207, the rotation mechanism 267, the wafer cassette elevator 115, the shutter switching mechanism 115s, and the like described above.

[0050] The CPU 121a is constituted so as to be able to read out the control program from the storage device 121c and execute it, and simultaneously read out the recipe from the storage device 121c in response to an input of an operation instruction from the input / output device 122 or the like. The CPU 121a is also constituted so as to be able to control the flow rate adjustment operation of each gas by the MFCs 241a to 241h, the opening / closing operation of the valves 243a to 243h, the opening / closing operation of the APC valve 244, the pressure adjustment operation by the APC valve 244 based on the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the rotation and rotation speed adjustment operation of the wafer cassette 217 by the rotation mechanism 267, the raising and lowering operation of the wafer cassette 217 by the wafer cassette elevator 115, the opening / closing operation of the furnace port shutter 219s by the shutter switching mechanism 115s, and the like in accordance with the content of the recipe read out.

[0051] The controller 121 can be configured by installing the above-described program stored in the external storage device 123 into the computer. The external storage device 123 includes, for example, a magnetic disk such as an HDD, an optical disk such as a CD, an optical-magnetic disk such as an MO, a USB memory, a semiconductor memory such as an SSD, and the like. The storage device 121c and the external storage device 123 are configured as a recording medium that is readable by the computer. Hereinafter, these will be simply collectively referred to as a recording medium. In the present specification, when the term "recording medium" is used, only the storage device 121c is included at times, only the external storage device 123 is included at times, or only both of them are included at times. Note that the program can be provided to the computer without using the external storage device 123, but can be performed using a communication method such as the Internet or a dedicated line.

[0052] Next, the use of the Figure 4 The port baffle 219s has a protection plate 219w disposed on the side facing the header 209 inside and larger than the lower end opening of the header 209, and a cover 219t disposed on the outer surface side and holding the protection plate 219w. Here, the outer surface of the port baffle means the surface in the direction of the outside of the process container when viewed from the port, and the inner surface means the surface in the direction of the inside of the process container when viewed from the port. The protection plate 219w disposed on the inner surface side is made of a material having higher corrosion resistance than the cover 219t, such as quartz glass, and is also called a baffle glass or a quartz plate. The port baffle has an outer peripheral surface (second sealing surface) facing the lower surface (first sealing surface) of the header 209. The second sealing surface is located Figure 4 and Figure 5 The outer periphery A of the cover 219t and the inner periphery B of the header 209 are formed by the outer peripheral portion of the protection plate 219w and the cover 219t. There is a gap 219u between the lower surface of the header 209 and the second sealing surface. On the outer side of the cover 219t in the second sealing surface, an O-ring 220c is provided, on the entire circumference of the cover 219t on the inner side thereof, a groove 219v is provided, and on the upper surface of the cover 219t on the inner side of the groove 219v, the outer peripheral portion of the protection plate 219w is provided.

[0053] In the lower flange of the manifold 209, a hole 249i as a gas introduction portion is formed in a position opposite to the groove 219v to communicate with the processing chamber 201. The hole 249i is connected to a purge gas supply pipe 232i that supplies a purge gas into the processing chamber 201. The upstream side of the purge gas supply pipe 232i opposite to the side connected to the hole 249i is connected to a purge gas supply source (not shown) via a valve 243i and an MFC 241i as a gas flow controller. The purge gas is supplied from the hole 249i to the groove 219v in the gap 219u between the lower surface of the manifold 209 and the second sealing surface, and to the inner peripheral side of the protection plate 219w through the gap 219u between the lower surface of the manifold 209 and the outer peripheral side of the protection plate 219w. The purge gas is supplied from the groove 219v during the supply of the cleaning gas into the processing container. The flow rate of the purge gas supplied from the groove 219v when the cleaning gas is supplied into the processing container is smaller than when the cleaning gas is not supplied into the processing container. The temperature in the processing container during cleaning can be set to be higher than the temperature of the wafer 200. Note that the groove 219v can also be provided on the lower surface side of the lower flange of the manifold 209. Further, the gap 219u can be provided continuously around the entire circumference or discontinuously.

[0054] The protection plate 219w is large enough to reach below the manifold 209, and is purged from the entire circumference through the groove 219v provided in the outer peripheral portion of the cover 219t. By purging from the entire circumference, the cleaning gas can be prevented from entering between the cover 219t and the protection plate 219w (the back surface of the protection plate 219w). Thus, the corrosion of the cover 219t can be prevented.

[0055] Further, the cover 219t has a flow path 219x for cooling water as a cooling medium. The flow path 219x is formed on the center side of the cover 219t, and is arranged along the circumferential direction in the radial central portion of the cover 219t, and is arranged along the circumferential direction on the inner side in the radial direction of the central portion. By flowing the cooling water in the flow path 219x, the cover 219t can be maintained in a predetermined temperature range (for example, 160 to 200°C).

[0056] Next, the use of the cleaning gas will be described. Figure 6 The cooling water system for maintaining the cover 219t in a predetermined temperature range will be described. If the surface temperature of the furnace port baffle 219s is below a predetermined temperature (for example, 150°C), the speed of the cleaning reaction can sometimes decrease, the cleaning gas can condense, and the detachment of the by-products can deteriorate. In order to reach the target temperature for effective cleaning, temperature control is performed by turning the cooling water on and off. Further, the cooling water used in other systems (for example, the heater 207 and the surrounding thereof) is used again, and the surface temperature of the furnace port baffle 219s is maintained by using the heated cooling water.

[0057] Here, in order to detect the temperature of the cooling water in the flow path 219x, a temperature sensor 301 is provided in the vicinity of the flow path 219x. In Figure 6 One temperature sensor 301 is shown, but a plurality of temperature sensors 301 can be provided. Further, a cooling medium supply pipe 311 that supplies cooling water is connected to the heater 207, and a discharge pipe 312 that discharges cooling water that has been heated by the heater 207 is connected to the heater 207 and the flow path switching device 302. A cooling medium supply pipe 313 that supplies cooling water discharged from the flow path switching device 302 is connected to the inlet of the flow path 219x of the lid 219t, and a discharge pipe 315 that discharges cooling water that has been heated by the lid 219t is connected to the outlet of the flow path 219x and the flow meter 303. The flow path switching device 302 is configured to switch the flow path based on the temperature sensor 301, to cause cooling water to flow to the port baffle 219s via the cooling medium supply pipe 313 when the temperature of the cooling water measured by the temperature sensor 301 reaches a predetermined temperature or more, and to reduce or stop the flow of cooling water to the lid 219t by discharging cooling water via the discharge pipe 314 when the temperature is less than the predetermined temperature. The flow meter 303 is configured by, for example, a Karman flow meter. The predetermined temperature is below the heat resistance temperature of the Karman flow meter, and is preferably 85°C.

[0058] (2) Substrate processing step

[0059] Hereinafter, the description will be made with reference to Figure 7 An example in which a predetermined film is formed on the wafer 200 will be described. Note that in the following description, the operation of each part that constitutes the substrate processing apparatus is controlled by the controller 121.

[0060] In the film formation processing of the present embodiment, a film of a metal oxide is formed on the wafer 200 by performing a cycle in which the following processes are not performed simultaneously for a predetermined number of times (one or more times): a process of supplying a raw material gas to the wafer 200 in the processing chamber 201 (S941), a process of removing the raw material gas (residual gas) from the processing chamber 201 (S942), a process of supplying a reaction gas to the wafer 200 in the processing chamber 201 (S943), and a process of removing the reaction gas (residual gas) from the processing chamber 201 (S944).

[0061] In the present specification, when the term "wafer" is used, the case in which the meaning of "the wafer itself (blank wafer)" is included, and the case in which the meaning of "a laminate (composite) of the wafer and a predetermined layer, film, or the like formed on the surface thereof" is included. Similarly, when the term "wafer surface" is used, the case in which the meaning of "the surface of the wafer itself" is included, and the case in which the meaning of "the surface of a predetermined layer, film, or the like formed on the wafer, that is, the outermost surface of the wafer as a laminate" is included. The term "substrate" is explained in the same manner as "wafer".

[0062] (S901: wafer loading and wafer boat mounting)

[0063] First, a plurality of wafers 200 are loaded into a wafer boat 217 (wafer loading), and then the furnace door shutter 219s is moved by the shutter opening and closing mechanism 115s to open the lower end opening of the manifold 209 (shutter opening). Then, as shown in FIG. 2, the wafer boat 217 supporting the plurality of wafers 200 is lifted by the wafer boat elevator 115 and carried into the processing chamber 201 (wafer boat mounting). In this state, the seal cap 219 becomes a state of sealing the lower end of the manifold 209 via the O-ring 220b. Figure 1

[0064] (S902: pressure adjustment)

[0065] Then, vacuum evacuation (depressurization evacuation) is performed by the vacuum pump 246 so that the processing chamber 201, i.e., the space in which the wafers 200 exist, reaches a desired pressure (degree of vacuum). At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and feedback control is performed on the APC valve 244 based on the measured pressure information. The evacuation in the processing chamber 201 is continued at least until the end of the processing of the wafers 200 (from the temperature rise S903 to the temperature decrease S905). During the evacuation, the valves 243e to 243g are opened, and a small amount of flow of the inactive gas controlled by the MFCs 241e to 241g can be continuously supplied to predetermined portions in the processing chamber 201. The seal cap 219 can distribute the purge gas supplied from the purge gas supply pipe 232i to the rotation mechanism 267 for the purge of the rotation mechanism 267, and the supply amount at this time is in the order of 100 to 1000 seem.

[0066] (S903: temperature rise)

[0067] Further, heating is performed by the heater 207 so that the wafers 200 in the processing chamber 201 reach a desired processing temperature. At this time, the energization of the heater 207 is feedback controlled based on the temperature information detected by the temperature sensor 263 so that the processing chamber 201 is stabilized at a desired temperature distribution. The processing temperature is 100 to 650°C, and when it is preferred to set a temperature that does not affect the impurity concentration of the channel region and the metal wiring and the like, for example, it is 100 to 350°C. Further, the rotation of the wafers 200 is started by the rotation mechanism 267. The heating and rotation of the wafers 200 in the processing chamber 201 are continued at least until the end of the processing of the wafers 200.

[0068] (S904: film formation processing)

[0069] ​After the temperature in the processing chamber 201 is stabilized at the preset processing temperature, the following four sub-steps, i.e., S941, S942, S943, and S944, are sequentially implemented. Note that during this period, the wafer boat 217 is rotated via the rotation shaft 255 by the rotation mechanism 267, so that the wafer 200 is also rotated.

[0070] (S941: Supply of raw material gas)

[0071] In this step, the raw material gas is supplied to the wafer 200 in the processing chamber 201, so that a first layer is formed on the outermost surface of the wafer 200. Specifically, the valve 243b is opened, and the raw material gas is flowed into the gas supply pipe 232b. The raw material gas is adjusted in flow rate by the MFC 241b, supplied to the processing region in the processing chamber 201 via the gas supply holes 250b of the nozzle 249b, and exhausted from the exhaust pipe 231 via the exhaust port 231a. At the same time, the valve 243f is opened, and the non-reactive gas is flowed into the gas supply pipe 232f. The non-reactive gas is adjusted in flow rate by the MFC 241f, supplied to the processing region in the processing chamber 201 via the gas supply holes 250b of the nozzle 249b together with the raw material gas, and exhausted from the exhaust pipe 231 via the exhaust port 231a. At the same time, the non-reactive gas is supplied to the processing region in the processing chamber 201 via the gas supply holes 250a, 250c of the nozzles 249a, 249c, and exhausted from the exhaust pipe 231 via the exhaust port 231a. At this time, the controller 121 performs pressure control with the first pressure as the target pressure. As the raw material gas, a gas containing metal elements such as Al, Zr, Hf, Ti, and the like can be used.

[0072] (S942: Exhaust of raw material gas)

[0073] After the first layer is formed, the valve 243b is closed, and the supply of the raw material gas is stopped, and at the same time, the APC valve 244 is controlled to be fully open. Thus, the processing chamber 201 is vacuum-exhausted, and the unreacted or remaining raw material gas in the processing chamber 201 after the formation of the first layer is exhausted from the processing chamber 201. Note that the state of opening the valve 243f can be maintained, and the non-reactive gas supplied to the processing chamber 201 can be used to purge the remaining gas. The flow rate of the purge gas from the nozzle 249b is set so that the partial pressure of the low-vapor-pressure gas in the exhaust path is lower than the saturated vapor pressure, or so that the flow rate in the reaction pipe 203 is higher than the diffusion speed.

[0074] (S943: Supply of reaction gas)

[0075] After the step S942, the wafer 200 in the processing chamber 201, i.e., the first layer formed on the wafer 200 is supplied with a reaction gas. The reaction gas after heat activation is reacted with at least a part of the first layer formed on the wafer 200 by the step S941, and is changed into a second layer (modification). The switching control of the valves 243a, 243e is performed in the same manner as the switching control of the valves 243b, 243f in the step S941. The reaction gas is supplied from the MFC 241a at a regulated flow rate, into the processing region in the processing chamber 201 through the gas supply hole 250a of the nozzle 249a, and is exhausted from the exhaust pipe 231 through the exhaust port 231a. At the same time, the non-active gas is supplied into the processing region in the processing chamber 201 through the gas supply holes 250a-250c of the nozzles 249a-249c, and is exhausted from the exhaust pipe 231 through the exhaust port 231a. At this time, the controller 121 performs the constant pressure control with the second pressure as the target pressure. The first pressure and the second pressure are, for example, 100-5000 Pa, and preferably 100-500 Pa. As the reaction gas, for example, oxygen (O2) gas, ozone (O3) gas, plasma-excited O2 gas (O2 ＊ ), O2 gas + hydrogen (H2) gas, water vapor (H2O gas), hydrogen peroxide (H2O2) gas, nitrous oxide (N2O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, carbon monoxide (CO) gas, carbon dioxide (CO2) gas, and the like oxygen (O) -containing gas can be used.

[0076] (S944: Reaction gas exhaust)

[0077] After the second layer is formed, the valve 243a is closed, and the supply of the reaction gas is stopped, and the constant pressure control with the target pressure of 0 (i.e., full opening control) is performed. Thus, the processing chamber 201 is vacuum-exhausted, and the unreacted or remaining reaction gas in the processing chamber 201 after the formation of the second layer is exhausted from the processing chamber 201. At this time, as in the step S942, a predetermined amount of the non-active gas can be supplied as a purge gas into the processing chamber 201. The pressure reached in the raw material gas exhaust or the reaction gas exhaust is 100 Pa or less, and preferably 10-50 Pa. The pressure in the processing chamber 201 differs by 10 times or more between the supply and the exhaust.

[0078] (S945: Execution of predetermined number of times)

[0079] The steps of S941 to S944 described above are sequentially performed in time without overlapping, as one cycle, and this cycle is performed a predetermined number of times (n times), whereby a film of a predetermined composition and a predetermined film thickness can be formed on the wafer 200. The thickness of the first layer and the second layer formed in S941 and S943 is not necessarily self-limiting, and in this case, in order to obtain a stable film quality, it is necessary to precisely control the gas concentration and the time during which exposure to the gas is performed with good reproducibility.

[0080] Note that, in the repeated cycle, S941 and S942 or S943 and S944 can be further repeated a plurality of times.

[0081] (S905: Temperature reduction)

[0082] In this step, the temperature adjustment of step S903, which is continuously performed during the film formation processing, is stopped or is re-set to a lower temperature as necessary, and the temperature in the processing chamber 201 is slowly reduced.

[0083] (S906: Purging and atmospheric pressure recovery)

[0084] After the film formation processing is completed, the non-active gas is supplied from the nozzles 249a to 249c into the processing chamber 201, and the exhaust port 231a is used for exhaust. The non-active gas supplied from the nozzles 249a to 249c functions as a purging gas, whereby the processing chamber 201 is purged, and the gas, reaction by-products, and the like remaining in the processing chamber 201 are removed from the processing chamber 201 (post-purging). Then, the atmosphere in the processing chamber 201 is replaced with the non-active gas (non-active gas replacement), and the pressure in the processing chamber 201 is recovered to the normal pressure (atmospheric pressure recovery).

[0085] (S907: Wafer boat unloading and wafer release)

[0086] Then, the sealed cap 219 is lowered by the wafer boat elevator 115, and the lower end of the manifold 209 is opened. Then, the processed wafer 200 is carried out from the lower end of the manifold 209 to the outside of the reaction tube 203 in a state of being supported by the wafer boat 217 (wafer boat unloading). After the wafer boat is unloaded, the furnace port shutter 219s is moved, and the lower end opening of the manifold 209 is sealed (closed shutter) by the furnace port shutter 219s via the O-ring 220c. After the processed wafer 200 is carried out to the outside of the reaction tube 203, the wafer 200 is removed from the wafer boat 217 (wafer release).

[0087] (S908: Pressure adjustment)

[0088] Then, vacuum evacuation (depressurization evacuation) is performed by the vacuum pump 246 so that the desired pressure (degree of vacuum) is reached in the processing chamber 201. At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and feedback control is performed on the APC valve 244 based on the measured pressure information. The evacuation in the processing chamber 201 is continued at least until the end of the cleaning process. During this period, the valves 243e to 243g can be opened, and a small flow rate of non-reactive gas can be supplied.

[0089] (S909: Temperature increase)

[0090] Further, heating is performed by the heater 207 so that the desired processing temperature is reached in the processing chamber 201. At this time, feedback control is performed on the power supply to the heater 207 based on the temperature information detected by the temperature sensor 263 so that the desired temperature distribution is reached in the processing chamber 201. The heating in the processing chamber 201 is continued at least until the end of the cleaning process.

[0091] (S910: Cleaning)

[0092] After the temperature in the processing chamber 201 is stabilized at the pre-set processing temperature, a cleaning gas is supplied into the processing chamber 201. Specifically, at least one of the valve 243c and the valve 243d is opened. The cleaning gas is adjusted in flow rate by the MFCs 241c, 241d, flows through the gas supply pipes 232c, 232d, is supplied into the processing chamber 201 via the gas supply holes 250c, 250a of the nozzles 249c, 249a, and is evacuated from the exhaust pipe 231 via the exhaust port 231a. At this time, the controller 121 performs constant pressure control with the third pressure as the target pressure. The APC valve 244 is almost fully closed before the pressure in the processing chamber 201 is raised to the third pressure. Further, the non-reactive gas supplied into the processing chamber 201 can be reduced to the minimum necessary.

[0093] As the cleaning gas, a gas containing a halogen atom, first, as a compound having a carbonyl group and a halogen atom in the molecule, COF2(carbonyl fluoride), COCl2(carbonyl chloride), COBr2(carbonyl bromide), COClF(carbonyl chloride fluoride), COBrF(carbonyl fluoride bromide), COIF(carbonyl iodine fluoride), and the like can be used. Further, the number of carbonyl groups in the molecule is not limited to one, and, for example, a compound having two carbonyl groups such as C2O2F2(oxalyl fluoride), C2O2Cl2(oxalyl chloride), C2O2Br2(oxalyl bromide), and the like can also be used. As a compound having a sulfinyl group and a halogen atom in the molecule, SOF2(sulfinyl fluoride), SOCl2(sulfinyl chloride), SOBr2(sulfinyl bromide), SOF4(tetrafluorosulfinyl), SOClBr(sulfinyl chloride bromide), and the like can be used. As a compound having a sulfonyl group and a halogen atom in the molecule, SO2Cl2(sulfonyl chloride), SO2ClF(sulfonyl chloride fluoride), SO2BrF(sulfonyl bromide fluoride), and the like can be used. As a compound having a nitrosyl group and a halogen atom in the molecule, NOF(nitrosyl fluoride), NOCl(nitrosyl chloride), NOCl2(nitrosyl dichloride), NOCl3(nitrosyl trichloride), NOBr(nitrosyl bromide), NOBr2(nitrosyl dibromide), NOBr3(nitrosyl tribromide), and the like can be used. Further, as a compound having a nitro group and a halogen atom in the molecule, NO2F(nitryl fluoride), NO2Br(nitryl bromide), and NO2Cl(nitryl chloride) can be used.

[0094] The oxide of Al, Hf, Zr, or the like formed by the film formation process S904 is a known high-k material, and is also a difficult-to-etch material. If these materials are converted into a chloride or a bromide having a high vapor pressure, etching can be performed without using plasma. Note that the cleaning process temperature is higher than the film formation process temperature, for example, 400 to 750°C. The third pressure is, for example, on the order of 10 kPa to 16,600 kPa.

[0095] In the cleaning S910, the controller 121 can maintain the temperature on the inner surface side of the furnace port shutter 219s at around the target temperature by the following control. That is, if the temperature of the cooling water measured by the temperature sensor 301 exceeds a first predetermined temperature, the supply to the flow path 219x is forcibly turned on, and is turned off after a predetermined time tl or after a predetermined amount w of cooling water has flowed. The amount of the cooling water that has flowed is obtained from the value of the cumulative flow meter 303, and the predetermined amount w is determined in correspondence with the volume of the flow path 219x. After the turning off, the turning off is maintained for a predetermined time t2 regardless of the temperature of the temperature sensor 301. Then, standby is performed until the temperature of the cooling water exceeds the predetermined temperature again. Further, a second temperature sensor for measuring the temperature on the inner surface side of the cover 219t is added, and if the second temperature sensor exceeds a second predetermined temperature, the process of forcibly turning on the supply to the flow path 219x can also be performed in parallel.

[0096] (S911: Purging and Atmospheric Restoration)

[0097] After the cleaning, non-active gas is supplied from the nozzles 249a to 249c into the processing chamber 201, and exhaust is performed from the exhaust port 231a. The non-active gas supplied from the nozzles 249a to 249c functions as a purge gas, whereby the processing chamber 201 is purged, and gases, reaction by-products, and the like remaining in the processing chamber 201 are removed from the processing chamber 201 (post-purge). Then, the atmosphere in the processing chamber 201 is replaced with non-active gas (non-active gas replacement), and the pressure in the processing chamber 201 is restored to the normal pressure (atmospheric restoration).

[0098] The present disclosure is not limited to the above-described embodiments, and various modifications can be made within the scope of the gist thereof. The above-described embodiments can be widely applied to the heat treatment of a substrate under reduced pressure by those skilled in the art. For example, the present disclosure is not limited to a hot-wall type reaction tube, and can also be applied to a cold-wall type tube with lamp heating, induction heating, and the like, and to various shapes of reaction tubes including a single-layer tube, a tube with a buffer (air pipe), and a double-layer tube. Figure 1 Such a single-layer tube, a tube with a buffer (air pipe), and a double-layer tube can also be applied.

[0099] The film formation is not limited to be performed on a substrate such as a wafer, and also includes being performed on the inner wall of a chamber (processing container) for the purpose of protection of the chamber, prevention of particle generation, and the like, and the furnace port baffle of the present disclosure can also be used for such (re)coating, removal of an existing protective film before coating.

Claims

1. A substrate processing apparatus having a processing container provided with an opening through which a substrate holder holding a substrate is allowed to pass in and out and a first seal surface formed around the opening, and a furnace port shutter provided with a second seal surface facing the first seal surface and capable of occluding the opening in a state where the substrate holder is not accommodated in the processing container, the furnace port shutter having a protection plate disposed on an inner surface side facing the processing container and larger than the opening, and a cover body disposed on an outer surface side and holding the protection plate, the second seal surface being formed by an outer peripheral portion of the protection plate and the cover body, purge gas being supplied to a gap between the first seal surface and the second seal surface from a more outer peripheral side than the protection plate.

2. The substrate processing apparatus according to claim 1, wherein the processing container or the furnace port shutter has a groove that supplies purge gas to the gap from a more outer peripheral side than the protection plate, the purge gas passing through the gap being supplied to an inner peripheral side of the protection plate.

3. The substrate processing apparatus according to claim 1 or claim 2, wherein the cover body is held within a predetermined temperature range.

4. The substrate processing apparatus according to claim 1, wherein the cover body has a flow path of a cooling medium that holds the cover body within a predetermined temperature range, and a temperature sensor that detects a temperature of the cooling medium in the flow path.

5. The substrate processing apparatus according to claim 4, configured in such a manner that the temperature of the cooling medium is supplied if it is a predetermined temperature or more, and the supply of the cooling medium is reduced or stopped if it is less than the predetermined temperature.

6. The substrate processing apparatus according to claim 4 or 5, further having a heating section that heats the substrate, the cooling medium being supplied to the flow path after being cooled by the heating section or its surroundings.

7. The substrate processing apparatus according to claim 4 or 5, wherein the flow path is configured on a center side of the cover body.

8. The substrate processing apparatus according to claim 2, wherein the purge gas is supplied from the groove during supply of a cleaning gas into the processing container.

9. The substrate processing apparatus according to claim 8, configured so that the temperature at the time of the gas cleaning is higher than the temperature at which the substrate is processed.

10. The substrate processing apparatus according to claim 2, wherein the flow rate of the purge gas supplied from the groove is reduced when a cleaning gas is supplied into the processing container than when no cleaning gas is supplied into the processing container.

11. The substrate processing apparatus according to claim 1, further having a seal cap that occludes the opening in a state where the substrate holder is rotatably supported in the processing container, and a rotation mechanism provided to the seal cap and rotating the substrate holder; the rotation mechanism supplying the purge gas supplied via the annular groove to the surroundings of a rotation shaft.

12. The substrate processing apparatus according to claim 4, wherein the predetermined temperature range is a range of 160°C or more and 200°C or less, and the cooling medium includes water. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 13. A furnace port assembly having a manifold and a furnace port shutter, the manifold constituting a furnace port portion of a processing vessel and having an opening through which a substrate holder holding a substrate is allowed to enter and exit and a first seal surface formed around the opening, the furnace port shutter having a second seal surface facing the first seal surface and occluding the opening in a state in which the substrate holder is not accommodated in the processing vessel; the furnace port shutter having a protection plate disposed on a side facing the inside of the processing vessel and larger than the opening and a cover body disposed on an outer surface side and holding the protection plate, the second seal surface being formed by an outer peripheral portion of the protection plate and the cover body, purge gas being supplied from a gap between the first seal surface and the second seal surface on an outer peripheral side farther than the protection plate.

14. A substrate processing method comprising: a process of carrying a substrate holder into a processing vessel via an opening, the processing vessel having a first seal surface formed around the opening; a process of processing a substrate held by the substrate holder in the processing vessel; a process of carrying the substrate holder out of the processing vessel; a process of occluding a furnace port shutter in a state in which the substrate holder is not accommodated in the processing vessel, the furnace port shutter having a protection plate configured to be larger than the opening and disposed on an inner surface side facing the inside of the processing vessel, a second seal surface facing the first seal surface, and a cover body holding the protection plate and disposed on an outer surface side; and a process of supplying purge gas to a gap between the first seal surface and the second seal surface from an outer peripheral side of the protection plate while cleaning the inside of the processing vessel.

15. A method of manufacturing a semiconductor device, comprising: a process of carrying a substrate holder into a processing vessel via an opening, the processing vessel having a first seal surface formed around the opening; a process of processing a substrate held by the substrate holder in the processing vessel; a process of carrying the substrate holder out of the processing vessel; a process of occluding a furnace port shutter in a state in which the substrate holder is not accommodated in the processing vessel, the furnace port shutter having a protection plate configured to be larger than the opening and disposed on an inner surface side facing the inside of the processing vessel, a second seal surface facing the first seal surface, and a cover body holding the protection plate and disposed on an outer surface side; and a process of supplying purge gas to a gap between the first seal surface and the second seal surface from an outer peripheral side of the protection plate while cleaning the inside of the processing vessel.

16. A computer-readable recording medium recording a program for causing a substrate processing apparatus to execute the following processes by a computer: a process of carrying a substrate holder into a processing vessel via an opening, the processing vessel having a first seal surface formed around the opening; a process of processing a substrate held by the substrate holder in the processing vessel; a process of carrying the substrate holder out of the processing vessel; A process of occluding a furnace port shutter with a shutter port in a state where the substrate holder is not accommodated in the processing container, the furnace port shutter including: a protection plate configured to be larger than the opening and disposed on an inner surface side facing the processing container; a second sealing surface facing the first sealing surface; and a cover body holding the protection plate and disposed on an outer surface side; and A process of supplying a purge gas to a gap between the first sealing surface and the second sealing surface from an outer peripheral side of the protection plate while cleaning the processing container.

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