Method of manufacturing semiconductor device, substrate processing apparatus, and recording medium

Abstract

The invention relates to a method of manufacturing a semiconductor device, a substrate processing apparatus, and a recording medium. It is possible to provide a technique for removing by-products before the accumulation of the by-products in the exhaust section develops. The provided technology includes a substrate processing step of processing a substrate while maintaining a processing pressure of a processing chamber by opening and closing a pressure adjusting valve, and an atmospheric pressure recovery step of changing the processing pressure of the processing chamber from the processing pressure to atmospheric pressure. A supply step of supplying a predetermined gas to the downstream side of a pressure regulation valve by bypassing a processing chamber is performed in parallel.

Description

[0001] This application is a divisional application of an invention patent application with an application date of May 22, 2020, an application number of 202010445863.5, an earliest priority date of May 28, 2019, and an invention name of “Manufacturing method of semiconductor device, substrate processing device and recording medium”. Technical Field

[0002] The present invention relates to a method for manufacturing a semiconductor device, a substrate processing apparatus and a recording medium. Background Art

[0003] In the past, the influence of the conductance of the exhaust pipe was not so great, but in recent years, in the process related to large-area 3D devices, the improvement of exhaust performance has received attention.

[0004] For example, Patent Document 1 discloses a technique for supplying a cleaning gas into an exhaust portion without passing through a processing chamber to clean an exhaust pipe. In addition, Patent Document 2 discloses a configuration for executing a cleaning process for removing the accumulated film thickness accumulated in the exhaust pipe when the accumulated film thickness accumulated in the exhaust pipe reaches a threshold value.

[0005] However, since these cleaning techniques are performed after the exhaust section becomes abnormal, the operating rate of the device may be reduced due to the maintenance of the exhaust section.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2013-153159

[0009] Patent Document 2: International Publication No. 2013 / 146595 Pamphlet Summary of the invention

[0010] Problems to be solved by the invention

[0011] An object of the present invention is to provide a technology for removing by-products before the by-products accumulate in an exhaust section.

[0012] Solutions to Solve Problems

[0013] One scheme of the present invention provides the following technology: a substrate processing step for processing a substrate while opening and closing a pressure regulating valve to maintain a processing pressure in a processing chamber, and an atmospheric pressure recovery step for changing the processing chamber from the processing pressure to atmospheric pressure, wherein when executing the atmospheric pressure recovery step, a supply step for bypassing the processing chamber and supplying a prescribed gas to a downstream side of the pressure regulating valve is executed in parallel.

[0014] The present invention includes the following technical solutions.

[0015] (1) A method for manufacturing a semiconductor device, comprising a substrate processing step of processing a substrate while maintaining a processing pressure in a processing chamber by opening and closing a pressure regulating valve, and an atmospheric pressure recovery step of returning the processing chamber from the processing pressure to atmospheric pressure,

[0016] When the atmospheric pressure restoring step is performed, a supplying step of supplying a predetermined gas to the downstream side of the pressure regulating valve while bypassing the processing chamber is performed in parallel.

[0017] (2) In the method for manufacturing a semiconductor device described in (1) above, when the atmospheric pressure recovery step and the supply step are performed in parallel,

[0018] The total time of the supply process is shorter than the total time of the atmospheric pressure recovery process.

[0019] (3) In the method for manufacturing a semiconductor device described in (1) above, when the atmospheric pressure recovery step and the supply step are performed in parallel,

[0020] The atmospheric pressure recovery step is started earlier than the supply step.

[0021] (4) In the method for manufacturing a semiconductor device described in (1) above, when the atmospheric pressure recovery step and the supply step are performed in parallel,

[0022] The pressure regulating valve is configured to be closed.

[0023] (5) In the method for manufacturing a semiconductor device described in (1) above, the predetermined gas used in the supply step and the gas used in the atmospheric pressure restoration step are different in gas type.

[0024] (6) In the method for manufacturing a semiconductor device described in (1) above, the predetermined gas is a cleaning gas or a purge gas.

[0025] (7) In the method for manufacturing a semiconductor device described in (4) above, the cleaning gas is a halogen-containing gas or a chlorine-containing gas.

[0026] (8) In the method for manufacturing a semiconductor device described in (6) above, the purge gas is an inert gas.

[0027] (9) In the method for manufacturing a semiconductor device described in (1) above, the concentration of the gas supplied in the supplying step can be changed.

[0028] (10) In the method for manufacturing a semiconductor device described in (1) above, the supply step is performed every time the substrate processing step is performed.

[0029] (11) The method for manufacturing a semiconductor device described in (1) above further comprises a preparation step of adjusting the processing chamber to the processing pressure before the substrate processing step.

[0030] When an abnormality occurs in the device data in the preparation process, the flow rate of the predetermined gas is adjusted.

[0031] (12) In the method for manufacturing a semiconductor device described in (1) above, there is further provided an exhaust device provided on the downstream side of the pressure regulating valve,

[0032] The device data is data of at least one of a current value, a rotation speed, and a back pressure of the exhaust device.

[0033] (13) The method for manufacturing a semiconductor device according to (11) above, further comprising:

[0034] a step of accumulating the device data collected in the preparation step; and

[0035] An average value of the acquired device data is calculated based on the accumulated device data, and the calculated average value is compared with the average value of the device data in a specified step calculated when executing the previous process, and a change in the average value is determined. If the change in the average value reaches a predetermined number of times, a process is performed to change the set flow rate of the specified gas.

[0036] (14) In the method for manufacturing a semiconductor device described in (13) above, the supply process is corrected by changing the flow rate of the prescribed gas and / or the time for which the prescribed gas is made to flow, thereby changing the set flow rate of the prescribed gas.

[0037] (15) A substrate processing apparatus comprising:

[0038] a processing chamber for processing a substrate;

[0039] a supply unit for supplying a prescribed gas;

[0040] Valves for pressure regulation; and

[0041] a control unit configured to cause the supply unit and the pressure regulating valve to perform substrate processing for processing a substrate while maintaining a processing pressure in the processing chamber by opening and closing the pressure regulating valve, and atmospheric pressure recovery processing for returning the processing chamber from the processing pressure to atmospheric pressure,

[0042] The control unit is configured to execute, while executing the atmospheric pressure recovery process, a supply process of bypassing the process chamber and supplying the predetermined gas to the downstream side of the pressure regulating valve in parallel.

[0043] (16) A computer-readable recording medium recording a program for causing a controller to cause a substrate processing apparatus to execute a process recipe, the process recipe comprising at least a substrate processing step of processing a substrate while maintaining a process pressure in a process chamber of the substrate processing apparatus by opening and closing a pressure regulating valve, and an atmospheric pressure recovery step of returning the process pressure in the process chamber to an atmospheric pressure from the process pressure,

[0044] The computer-readable recording medium records a program for causing, when the atmospheric pressure restoring step is executed, a supplying step of bypassing the processing chamber and supplying a predetermined gas to the downstream side of the valve to be executed in parallel.

[0045] Effects of the Invention

[0046] According to the present invention, by-products can be removed before they are deposited in the exhaust section. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a perspective view showing a substrate processing apparatus preferably used in one embodiment of the present invention.

[0048] Figure 2 It is a longitudinal sectional view showing a processing furnace of a substrate processing apparatus according to one embodiment of the present invention.

[0049] Figure 3 This is a block diagram showing a control configuration used in a substrate processing apparatus according to an embodiment of the present invention.

[0050] Figure 4 It is a diagram showing the current value, the rotation speed, and the back pressure of the assist pump during execution of the process recipe according to one embodiment of the present invention.

[0051] Figure 5 FIG. 1 is a diagram showing an exhaust system of a substrate processing apparatus according to an embodiment of the present invention.

[0052] Figure 6 It is a diagram showing the exhaust gas cleaning process according to one embodiment of the present invention.

[0053] Figure 7 It is shown Figure 6 FIG. 2 is a diagram of an experimental example of exhaust gas cleaning treatment shown in FIG.

[0054] Figure 8 A diagram showing a control flow during execution of a process recipe used in a substrate processing apparatus according to an embodiment of the present invention.

[0055] Fig. 9 (A) shows Figure 8 FIG. 2 is a diagram showing a control flow of a cleaning gas set flow rate change process. Fig. 9 (B) is a diagram showing an example of data stored in the storage unit.

[0056] Fig.10 It is shown Figure 8 , Fig. 9 (A) and Fig. 9 (B) is a diagram showing the back pressure of the auxiliary pump during the process execution.

[0057] Description of Reference Numerals

[0058] 100…Substrate processing device

[0059] 200…Wafer (substrate)

[0060] 217 ... Boat (substrate holder)

[0061] 244…Auxiliary pump (pump) DETAILED DESCRIPTION

[0062] <One embodiment of the present invention>

[0063] Hereinafter, one embodiment of the present invention will be described.

[0064] (1) Configuration of substrate processing apparatus

[0065] Reference Figure 1 and Figure 2 , a structure of a substrate processing apparatus 100 according to an embodiment of the present invention will be described.

[0066] like Figure 1 As shown, the substrate processing apparatus 100 includes a housing 111 configured as a pressure-resistant container. An opening is provided on the front wall of the housing 111 to enable maintenance, and a pair of front maintenance doors 104 are provided at the opening as an entry mechanism for opening and closing the opening. A wafer box 110 containing wafers such as silicon (hereinafter also referred to as substrates) 200 is used as a carrier for transporting the wafers 200 into and out of the housing 111.

[0067] A wafer box loading and unloading port is provided on the front wall of the frame 111 so as to communicate with the inside and outside of the frame 111. The wafer box loading and unloading port is provided with a loading port 114. The wafer box 110 is placed on the loading port 114 and the wafer box 110 is aligned.

[0068] A rotary cassette rack 105 is provided at an upper portion substantially in the center of the housing 111. The rotary cassette rack 105 is configured to store a plurality of cassettes 110.

[0069] A wafer box transfer device 118 is provided between the load port 114 and the rotary wafer box rack 105 in the housing 111. The wafer box transfer device 118 is configured to transfer the wafer box 110 between the load port 114, the rotary wafer box rack 105, and the wafer box opener 121 by continuously operating a wafer box elevator 118a and a wafer box transfer mechanism 118b that can be raised and lowered while holding the wafer box 110.

[0070] A sub-frame 119 is provided in the lower part of the frame 111 from the substantially center to the rear end of the frame 111. A pair of wafer box openers 121 for transferring wafers 200 into and out of the sub-frame 119 are provided on the front wall of the sub-frame 119, respectively.

[0071] Each wafer box opener 121 includes a mounting table for mounting the wafer box 110 and a cover mounting and dismounting mechanism 123 for mounting and dismounting the cover of the wafer box 110. The wafer box opener 121 is configured to mount and dismount the cover of the wafer box 110 mounted on the mounting table through the cover mounting and dismounting mechanism 123 to open and close the wafer inlet and outlet of the wafer box 110.

[0072] A transfer chamber 124 is formed in the sub-frame 119, which is isolated from the transfer space fluid in which the wafer box transfer device 118 and the like are provided. A wafer transfer mechanism 125 is provided in the front area of ​​the transfer chamber 124. The wafer transfer mechanism 125 is composed of a wafer transfer device 125a that can rotate and translate the wafer 200 in the horizontal direction and a wafer transfer device elevator 125b that can lift and lower the wafer transfer device 125a. The wafer 200 can be loaded (filled) and unloaded (taken out) relative to the boat 217 as a substrate holder by the continuous operation of the wafer transfer device elevator 125b and the wafer transfer device 125a.

[0073] like Figure 1 and Figure 2 As shown, a boat elevator 115 for raising and lowering a boat 217 is provided in a sub-frame 119. A processing furnace 202 is provided above a standby portion 126 for accommodating the boat 217 and making it standby. An arm is connected to the lifting platform of the boat elevator 115. A cover 219 is horizontally assembled on the arm. The cover 219 is configured to vertically support the boat 217 and to be able to block the lower end of the processing furnace 202.

[0074] (2) Composition of treatment furnace

[0075] like Figure 2As shown, the processing furnace 202 is provided with a processing tube 203 as a reaction tube. The processing tube 203 is provided with an inner tube 204 as an internal reaction tube and an outer tube 205 as an external reaction tube provided outside the inner tube 204. A processing chamber 201 for processing a wafer 200 is formed in a hollow portion of the inner tube 204 which is formed in a cylindrical shape with an upper end and a lower end opened. The processing chamber 201 is configured to accommodate a boat 217.

[0076] A heater 206 is provided outside the processing tube 203 so as to surround the side wall surface of the processing tube 203. The heater 206 is configured in a cylindrical shape. The heater 206 is supported by a heater base 251 as a holding plate and is vertically assembled.

[0077] A manifold 209 as a furnace opening is disposed below the outer tube 205 in a concentric manner with the outer tube 205. In addition, the manifold 209 is formed in a cylindrical shape with an upper end and a lower end opened. It should be noted that an O-ring 220a as a sealing member is provided between the manifold 209 and the outer tube 205. The manifold 209 is supported on the heater base 251, so that the processing tube 203 is in a vertically assembled state. The processing tube 203, the manifold 209 and the cover 219 form a reaction container, and the processing chamber 201 is formed in the reaction container.

[0078] An O-ring 220 b serving as a sealing member that abuts against the lower end of the manifold 209 is provided on the upper surface of the cover 219 .

[0079] A rotating mechanism 254 for rotating the boat 217 is provided near the center of the cover 219 and on the opposite side to the processing chamber 201. The rotating mechanism 254 is configured to rotate the wafer 200 by rotating the boat 217.

[0080] The cover 219 is configured to be raised and lowered in the vertical direction by the boat elevator 115 provided outside the processing tube 203. The boat 217 can be transported in and out of the processing chamber 201 by raising and lowering the cover 219.

[0081] The transfer mechanism of this embodiment is mainly composed of the rotary wafer cassette rack 105, the boat elevator 115, the wafer cassette transfer device 118, the wafer transfer mechanism 125, the boat 217 and the rotation mechanism 254. These transfer mechanisms are electrically connected to the transfer controller 11.

[0082] The boat 217 is configured to hold a plurality of wafers 200 in multiple layers. A plurality of heat insulating plates 216 as heat insulating members are disposed in multiple layers in a horizontal posture at the bottom of the boat 217 .

[0083] A temperature sensor 263 as a temperature detector is provided in the processing tube 203. The heating mechanism of this embodiment is mainly composed of the heater 206 and the temperature sensor 263. The temperature controller 12 is electrically connected to these heater 206 and the temperature sensor 263.

[0084] The manifold 209 is connected to a nozzle 230a, a nozzle 230b, and a nozzle 230c so as to communicate with the processing chamber 201. Gas supply pipes 232a, 232b, and 232e are connected to the nozzles 230a, 230b, and 230c, respectively.

[0085] The gas supply pipes 232a and 232b are provided with a gas supply source (not shown), valves 245a and 245b, MFC241a and 241b, and valves 243a and 243b in order from the upstream side of the gas flow. Gas supply pipes 232c and 232d are connected to the gas supply pipes 232a and 232b on the downstream side of the valves 243a and 243b. The gas supply pipes 232c and 232d are provided with a purge gas supply source (not shown), valves 245c and 245d, MFC241c and 241d, and valves 243c and 243d in order from the upstream side of the gas flow.

[0086] The gas supply pipe 232e is provided with a clean gas supply source (not shown), a valve 245e, an MFC 241e, and a valve 243e in order from the upstream side of the gas flow. In addition, a gas supply pipe 232f is connected to the gas supply pipe 232e on the upstream side of the valve 245e. The gas supply pipe 232f is provided with a valve 245f, an MFC 241f, and a valve 243f in order from the upstream side of the gas flow, and the downstream side of the gas supply pipe 232f is connected to the upstream side of the auxiliary pump 244 (hereinafter also referred to as the pump) as the exhaust device of the exhaust unit 310 as the exhaust system and to the downstream side of the APC (Auto Pressure Contoroller: automatic pressure controller) valve 242 as the pressure regulating part (for pressure regulation). The gas supply pipes 232e and 232f are connected to the downstream side of the valves 243e and 243f, respectively. The gas supply pipes 232g and 232h are provided with a purge gas supply source (not shown), valves 245g and 245h, MFCs 241g and 241h, and valves 243g and 243h in order from the upstream side of the gas flow.

[0087] It should be noted that, not limited to the present embodiment, although not shown in the figure, the gas supply pipe 232f can also be set on the upstream side of the APC valve 242. In addition, the gas supply pipe 232f1 can also be set on the upstream side of the APC valve 242, and the gas supply pipe 232f2 can be set on the downstream side of the APC valve 242 and on the upstream side of the pump 244.

[0088] The processing gas supply system of this embodiment mainly includes a gas supply source (not shown), valve 245a, MFC241a, valve 243a, gas supply pipe 232a and nozzle 230a. The reaction gas supply system of this embodiment mainly includes a gas supply source (not shown), valve 245b, MFC241b, valve 243b, gas supply pipe 232b and nozzle 230b. The purge gas supply system of this embodiment mainly includes a purge gas supply source (not shown), valves 245c, 245d, 245g, 245h, MFC241c, 241d, 241g, 241h, valves 243c, 243d, 243g, 243h, gas supply pipes 232c, 232d, 232g, 232h and nozzles 230a, 230b. The cleaning gas supply system of this embodiment is mainly composed of a cleaning gas supply source (not shown), a valve 245e, an MFC241e, a valve 243e, a gas supply pipe 232e and a nozzle 230c. The exhaust cleaning gas supply system of this embodiment is mainly composed of a cleaning gas supply source (not shown), a valve 245f, an MFC241f, a valve 243f and a gas supply pipe 232f. The gas supply unit 300 as the gas supply system of this embodiment is mainly composed of a processing gas supply system, a reaction gas supply system, a purge gas supply system, a cleaning gas supply system and an exhaust cleaning gas supply system. The gas supply controller 14 is electrically connected to the MFC241a~241h, the valves 243a~243h and the valves 245a~245h.

[0089] An exhaust pipe 231 for exhausting the atmosphere of the processing chamber 201 is provided on the manifold 209. The exhaust pipe 231 is arranged at the lower end of the cylindrical space 250 formed by the gap between the inner tube 204 and the outer tube 205. A pressure sensor 245 as a pressure detection unit, an APC valve 242, a pump 244, a pressure sensor 247 and a main pump (not shown) as a second exhaust device are provided on the exhaust pipe 231 in sequence from the upstream side of the air flow (the processing chamber 201 side). The pump 244 is used to accelerate the exhaust speed of the atmosphere of the processing chamber 201 and assist the operation of the main pump (not shown). As the pump 244, for example, a booster pump can be used. The pressure sensor 247 measures the back pressure of the pump 244. For example, it is configured so that if the pump 244 and the exhaust pipes 231 before and after it are blocked, it can be detected immediately based on the change in the detected pressure value. The sensor disposed on the downstream side of the pump 244 in this manner may be any sensor capable of detecting an abnormality in the pump 244 , and is not limited to the pressure sensor 247 .

[0090] The exhaust unit 310 is composed of the exhaust pipe 231, the pressure sensor 245, the APC valve 242, the pump 244 and the pressure sensor 247. It should be noted that the exhaust unit 310 may also include a main pump (not shown). Figure 2 As shown, the diameter of the exhaust pipe 231 on the upstream side of the pump 244 is larger than the diameter of the exhaust pipe 231 on the downstream side of the pump 244 .

[0091] The pressure controller 13 is electrically connected to the APC valve 242 and the pressure sensor 245. The exhaust controller 15 is electrically connected to the pressure sensor 247, the pump 244, and the main pump (not shown).

[0092] That is, the substrate processing apparatus 100 is as follows Figure 2 As shown, the structure includes at least a frame 111 , a gas supply unit 300 , and an exhaust unit 310 .

[0093] like Figure 2 As shown, the controller 240 as a control unit is connected to the transport controller 11, the temperature controller 12, the pressure controller 13, the gas supply controller 14, and the exhaust controller 15, respectively.

[0094] (3) Configuration of controller 240

[0095] Reference Figure 3 The control structure of the controller 240 will be described.

[0096] The controller 240 is mainly composed of a main control unit 25 such as a CPU (Central Processing Unit), a storage unit 28 such as a memory (RAM) and a hard disk, an input unit 29 such as a mouse and a keyboard, and a display unit 31 such as a monitor. It should be noted that the main control unit 25, the storage unit 28, the input unit 29 and the display unit 31 constitute an operation unit capable of setting various data.

[0097] The storage unit 28 includes a data storage area 32 for storing various processing data such as device data and a program storage area 33 for storing various programs. Here, the processing data is data related to substrate processing such as processing temperature, processing pressure, and flow rate of processing gas when the substrate processing apparatus 100 processes the wafer 200, data related to the quality of the manufactured product substrate (for example, the film thickness of the formed film and the cumulative value of the film thickness, etc.), component data related to the components of the substrate processing apparatus 100 (quartz reaction tube, heater, valve, MFC, etc.), and data generated by operating each component when the substrate processing apparatus 100 processes the wafer 200. It should be noted that the device data will be described later.

[0098] The program storage area 33 stores various programs required for controlling the device, including process recipes and cleaning recipes.

[0099] Here, the process is a process including a plurality of steps, and at least includes a substrate processing step (hereinafter also referred to as a film forming step) of processing the wafer 200 while opening and closing the valve to maintain the processing pressure and an atmospheric pressure recovery step (hereinafter also referred to as an atmospheric pressure recovery step) of changing the processing chamber 201 from the processing pressure to the atmospheric pressure, and the process is defined in the process including the processing conditions, processing steps, etc. for processing the wafer 200. In addition, in the present embodiment, a cleaning step (hereinafter also referred to as an exhaust cleaning step) may be configured to include a supply step of supplying a cleaning gas as a prescribed gas to the downstream side of the APC valve 242 while bypassing the processing chamber 201.

[0100] Various parameters associated with the process file are stored in the data storage area 32. In addition, the various processing data mentioned above are stored in the data storage area 32. In the present embodiment, the device data, especially the device data indicating the state of the exhaust unit 310 during the execution of the process, are accumulated and stored among the various processing data. Specifically, the current value, rotation speed, and back pressure of the pump 244 are stored as device data. In particular, the average value of the device data of the group consisting of the current value, rotation speed, and back pressure of the pump 244 in the predetermined specific steps of each step constituting the process is stored. In addition, in the data storage area 32, the device data types of the group consisting of at least the current value, rotation speed, and back pressure of the pump 244, the abnormal tendency of each device data type, and the monitoring parameters defined by the set value (number of times) set for each device data type are stored. In addition, as monitoring parameters, threshold values ​​are set for each device data type.

[0101] In addition, in the data storage area 32, for each device data type, a pre-set number of times (set value), the number of alarms that occur when there is a tendency to continuously indicate abnormalities, the set flow rate of the cleaning gas when performing the exhaust cleaning process described later corresponding to the number of alarms (hereinafter also referred to as the initial flow rate), and the limit number of alarms are saved as device data.

[0102] In addition, in the recipe file, set values ​​(control values) and transmission timings to be sent to the transport controller 11, the temperature controller 12, the pressure controller 13, the gas supply controller 14, the exhaust controller 15, etc. are set for each step.

[0103] A touch panel is provided on the display unit 31. The touch panel is configured to display an operation screen for receiving input of operation commands for the substrate transport system, substrate processing system, etc. It should be noted that the operation unit is an operation terminal (terminal device) such as a personal computer or a mobile phone, and it only needs to include at least the display unit 31 and the input unit 29.

[0104] The main control unit 25 has the function of controlling the temperature and pressure of the processing chamber 201, the flow rate of the processing gas introduced into the processing chamber 201, etc., so as to perform a predetermined process on the wafer 200 loaded in the processing chamber 201. In addition, after a predetermined specific step among the steps constituting the process recipe is completed, the main control unit 25 executes a process of bypassing the processing chamber 201 and directly supplying a predetermined gas to the components including the exhaust pipe 231 in the exhaust unit 310. For example, in this process, the components constituting the exhaust unit 310 including the exhaust pipe 231 are cleaned.

[0105] That is, the main control unit 25 executes the control program stored in the storage unit 28, and executes the process (for example, a process as a substrate processing process, a cleaning process, etc.) stored in the storage unit 28 according to the input from the input unit 29 or the instruction from the upper controller such as the host device located outside. In addition, the main control unit 25 controls in a manner of acquiring device data during the execution of the process and storing it in the data storage area 32 of the storage unit 28. It should be noted that the cleaning process is a process that defines the processing conditions, processing steps, etc. for cleaning the components of the processing chamber 201 constituting the processing wafer 200 or the components arranged in the processing chamber 201.

[0106] Specifically, the device data in the predetermined specific step constituting the process recipe is data associated with the exhaust unit 310 for exhausting the atmosphere of the processing chamber 201, and can be appropriately selected from the group consisting of the current value, rotation speed, and back pressure of the pump 244. At least one device data of the current value, rotation speed, and back pressure of the pump 244 is selected and set as the monitoring parameter. In addition, as the device data, multiple data can be selected from the group consisting of the current value, rotation speed, and back pressure of the pump 244, and multiple device data of the current value, rotation speed, and back pressure of the pump 244 can be selected.

[0107] In addition, the main control unit 25 adds at least one device data in the group consisting of the current value, the rotation speed, and the back pressure of the pump 244 in the specific step of the process at a certain interval. In addition, the main control unit 25 compares the average value of the device data calculated by the addition with the average value of the device data of the pump 244 in the specific step of the previous process, and determines whether the change in the average value of the device data is a tendency indicating abnormality defined for each device data type in the monitoring parameters.

[0108] Here, as a trend indicating an abnormality, the main control unit 25 compares the average value of the device data in the specific step preset in the previous process recipe with the average value of the device data, and determines that there is an upward trend when the average value of the device data in the specific step of the current process recipe rises to a preset value (threshold), for example, an increase of more than 10%. In addition, when the average value of the device data in the specific step of the current process recipe drops by a preset value (threshold), for example, a decrease of more than 10%, compared with the average value of the device data in the specific step preset in the previous process recipe, it is determined that there is a downward trend. In addition, when the average value of the device data in the specific step of the current process recipe is lower than the preset value (threshold), for example, when there is a change of ±10%, compared with the average value of the device data in the specific step preset in the previous process recipe, it is determined that there is no change.

[0109] Furthermore, for the main control unit 25, when the change in the average value does not indicate an abnormal tendency, or when the abnormal tendency continues and does not reach the set value, that is, when the preset abnormal tendency is less than the preset number of times, the main control unit 25 performs the following exhaust cleaning process, wherein the atmosphere of the processing chamber 201 after the film forming process in the process is replaced with an inert gas (inert gas replacement), and the cleaning gas is set to a preset initial value (initial flow rate) in the process of returning the pressure in the processing chamber 201 to normal pressure (atmospheric pressure recovery) and supplied to the components constituting the exhaust unit 310. In addition, the type of the cleaning gas and the initial flow rate are appropriately determined, for example, based on the type and amount of byproducts estimated to be attached to the exhaust pipe 231 or the pump 244 in the film forming process described later. It should be noted that when the tendency indicating an abnormality is lower than a pre-set number of times (lower than a set value), if the change in the average value of the device data in a specific step is judged to be normal (no change), the main control unit 25 sets the counter (Japanese: カウンタ) that counts the tendency of the change in the average value of the device data to indicate an abnormality to 0.

[0110] When the change in the average value of the device data indicates an abnormal tendency defined for each device data type, and the abnormal tendency occurs continuously and continuously for a predetermined number of times (when the set value is reached), the main control unit 25 controls the set flow rate of the clean gas to be changed relative to the initial value before supplying the clean gas to the components constituting the exhaust unit 310. That is, the main control unit 25 determines that the exhaust pipe 231, the pump and other exhaust devices begin to be blocked and increase the amount of the clean gas. In this case, the main control unit 25 controls so that the flow rate of the clean gas is changed by changing the flow rate of the clean gas and / or the supply time of the clean gas. In addition, the main control unit 25 controls so that when the change in the average value indicates an abnormal tendency and the abnormal tendency continues for a predetermined number of times, an alarm is issued, and a message is notified to the main device and the display unit 31 and the number of occurrences of the alarm is counted. In addition, the cleaning process (cleaning process) described later can also be performed after the process is completed.

[0111] In addition, the main control unit 25 controls so that the number of occurrences of the alarm is accumulated and counted until the replacement, inspection, or other maintenance of the components constituting the exhaust unit 310 is performed, and the set flow rate of the cleaning gas in the cleaning step is changed according to the number of occurrences of the alarm. It should be noted that after the maintenance is performed, the alarm counter, which is the accumulated value of the number of occurrences of the alarm, is cleared to 0.

[0112] As described above, the main control unit 25 is configured to execute a cleaning step of supplying a cleaning gas at a preset initial flow rate to the components constituting the exhaust unit 310 in a step (in parallel with the step) in which the atmosphere of the processing chamber 201 is replaced with an inert gas (inert gas replacement) and the pressure in the processing chamber 201 is restored to normal pressure (atmospheric pressure restoration) after the film forming process in the process. In addition, the main control unit 25 is configured to fully close the APC valve 242 and start the cleaning step when the atmospheric pressure restoration step and the cleaning step are executed in parallel.

[0113] In addition, the main control unit 25 is configured to control so that an alarm is issued when an abnormality is detected, the set flow rate of the cleaning gas is changed from the initial value according to the number of occurrences of the alarm, and the cleaning step is performed in parallel with the atmospheric pressure recovery process according to the changed set flow rate. In addition, the main control unit 25 is configured to control so that an alarm is issued and a message is notified to the main device and the display unit 31 when the counter of the accumulated number of occurrences of the alarm reaches a preset limit number, and the execution of the next process is prohibited.

[0114] It should be noted that, for example, the device data type of the monitoring parameter, the tendency indicating abnormality as a predefined tendency, and the set value (number of times) as a predefined number of times can be set independently for each device data in the operation unit. In addition, it is configured so that each parameter such as the above-mentioned device data type defined in the monitoring parameter can be set not only by the operation unit of the main control unit 25, but also by remote setting by an external computer.

[0115] The transport controller 11 is configured to notify the controller 240 of the corresponding contents when the sensors attached to the respective transport mechanisms indicate a predetermined value, an abnormal value, or the like.

[0116] The temperature controller 12 is configured to adjust the temperature in the processing furnace 202 by controlling the temperature of the heater 206 of the processing furnace 202, and to notify the controller 240 of the corresponding contents when the temperature sensor 263 indicates a predetermined value, an abnormal value, etc.

[0117] The pressure controller 13 is configured to control the APC valve 242 based on the pressure value detected by the pressure sensor 245 so that the pressure of the processing chamber 201 becomes the desired pressure at the desired time, and to notify the controller 240 of the corresponding content when the pressure sensor 245 shows a specified value, an abnormal value, etc.

[0118] The gas supply controller 14 is configured to control the MFCs 241a to 241h so that the flow rate of the gas supplied into the processing chamber 201 becomes a desired flow rate at a desired timing. In addition, the gas supply controller 14 is configured to control the opening and closing of the valves 243a to 243h and the valves 245a to 245h.

[0119] The exhaust controller 15 is configured to control the pump 244 and the main pump (not shown) and to control so that the atmosphere of the processing chamber 201 is exhausted to the outside of the processing chamber 201. In addition, the exhaust controller 15 is configured to monitor the current value and rotation speed of the pump 244 and the back pressure of the pump 244 detected by the pressure sensor 247 and send the changes thereof to the controller 240. It should be noted that the exhaust controller 15 is configured to monitor the current value, rotation speed, and back pressure of the main pump (not shown) in the same manner.

[0120] (4) Operation of substrate processing apparatus

[0121] Next, refer to Figure 1 to Figure 3 The operation of each component constituting the substrate processing apparatus 100 will be described. It should be noted that the operation of each component constituting the substrate processing apparatus 100 is controlled by the controller 240 .

[0122] like Figure 1As shown, when the wafer cassette 110 is supplied to the load port 114 , the wafer cassette 110 on the load port 114 is carried into the housing 111 from the wafer cassette carrying-in / out port by the wafer cassette transfer device 118 .

[0123] The wafer cassette 110 loaded into the housing 111 is automatically transferred to the shelf of the rotary cassette rack 105 by the cassette transfer device 118 and temporarily stored. Thereafter, the wafer cassette 110 is transferred from the shelf to a mounting table of a cassette opener 121 .

[0124] The cover of the wafer box 110 placed on the stage is removed by the cover installation and removal mechanism 123, and the wafer access port is opened. After that, the wafer 200 is picked up from the wafer box 110 through the wafer access port by the tweezers of the wafer transfer device 125a and loaded (filled) into the boat 217 after the orientation is matched by the notch matching device (not shown). The wafer transfer device 125a loaded with the wafer 200 on the boat 217 returns to the stage on which the wafer box 110 is placed, takes out the next wafer 200 from the wafer box 110, and loads it into the boat 217.

[0125] During the loading operation of the chip 200 into the boat 217 by the chip transfer mechanism 125 in the one (upper or lower) chip box opener 121, another chip box 110 is transferred to the loading table of another (lower or upper) chip box opener 121, and the opening operation of the chip box 110 based on the chip box opener 121 is performed at the same time.

[0126] When a predetermined number of wafers 200 are loaded into the boat 217 (wafer filling), a substrate processing step described below is performed. When the film forming process is completed, the processed wafers 200 are taken out of the boat 217 and stored in the wafer cassette 110 (wafer taking out).

[0127] After the wafer is taken out, the wafer cassette 110 storing the processed wafers 200 is carried out of the frame 111 in a substantially reverse process to the above process except for the matching process using the notch alignment device.

[0128] (5) Substrate processing step

[0129] Next, the substrate processing step will be described in detail. When the substrate processing step is performed, the main control unit 25 executes the process recipe stored in the program storage area 33 of the storage unit 28 .

[0130] Here, an example is described in which hexachlorodisilane (Si2Cl6, abbreviated as: HCDS) gas is used as a raw material gas and ammonia (NH3) gas is used as a reaction gas to form a silicon nitride film (Si3N4 film, hereinafter also referred to as SiN film) on a wafer 200. It should be noted that in the following description, the operations of the various parts constituting the substrate processing apparatus 100 are controlled by the controller 240.

[0131] In the substrate processing step in this embodiment, a SiN film is formed on the chip 200 by non-simultaneously performing a process of supplying HCDS gas to the chip 200 in the processing chamber 201, a process of removing HCDS gas (residual gas) from the processing chamber 201, a process of supplying NH3 gas to the chip 200 in the processing chamber 201, and a process of removing NH3 gas (residual gas) from the processing chamber 201 for a predetermined number of times (more than once) to cycle.

[0132] In this specification, the word "substrate" has the same meaning as the word "wafer".

[0133] (Boat loading process)

[0134] After a plurality of wafers 200 are loaded into the boat 217 (wafer filling), the boat 217 is carried into the processing chamber 201 (boat loading) by the boat elevator 115. At this time, the lid 219 is in a state of hermetically sealing the lower end of the manifold 209 via the O-ring 220b.

[0135] (Preparation process)

[0136] The processing chamber 201 is evacuated from atmospheric pressure to a predetermined pressure by the pump 244 and the main pump (not shown). At this time, the pressure of the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 242 is feedback-controlled based on the measured pressure information. In addition, the back pressure of the pump 244 is measured by the pressure sensor 247. The pump 244 and the main pump (not shown) are always kept in an operating state until at least the processing of the wafer 200 is completed.

[0137] In addition, the heater 206 heats the wafer 200 in the processing chamber 201 to a predetermined temperature. At this time, the power supply status of the heater 206 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the processing chamber 201 has a predetermined temperature distribution. The heating of the processing chamber 201 by the heater 206 is continuously performed at least until the processing of the wafer 200 is completed.

[0138] In addition, the rotation of the boat 217 and the wafer 200 by the rotation mechanism 254 is started. The boat 217 rotates by the rotation mechanism 254, thereby rotating the wafer 200. The rotation of the boat 217 and the wafer 200 by the rotation mechanism 254 is continued at least until the processing of the wafer 200 is completed.

[0139] (Purge process)

[0140] Then, valves 245c, 243c, 245d, 243d, 245g, and 243g are opened, and N2 gas is supplied from gas supply pipes 230a, 230b, and 230c to the processing chamber 201 and exhausted from the exhaust unit 310. The N2 gas functions as a purge gas, and the processing chamber 201 is purged.

[0141] (Film Forming Process)

[0142] If the temperature of the processing chamber 201 is stabilized at the preset processing temperature, the following two steps, ie, steps 1 and 2, are sequentially performed.

[0143] [Step 1]

[0144] In this step, HCDS gas is supplied to the wafer 200 in the process chamber 201 .

[0145] The valves 245a and 243a are opened to allow the HCDS gas to flow to the gas supply pipe 232a. The HCDS gas is supplied to the processing chamber 201 through the nozzle 230a and exhausted from the exhaust unit 310 after the flow rate is adjusted by the MFC 241a. At this time, the HCDS gas is supplied to the wafer 200. At this time, the valves 245c and 243c are opened at the same time, and the N2 gas is supplied to the processing chamber 201 together with the HCDS gas through the MFC 241c and exhausted from the exhaust pipe 231. By supplying the HCDS gas to the wafer 200, a silicon (Si)-containing layer having a thickness of, for example, several atomic layers is formed as the first layer on the outermost surface of the wafer 200.

[0146] After the first layer is formed, the valves 245a and 243a are closed to stop the supply of HCDS gas. At this time, the APC valve 242 is kept open, and the processing chamber 201 is vacuum-exhausted by the pump 244 and the main pump (not shown), and the HCDS gas remaining in the processing chamber 201 that has not reacted or participated in the formation of the first layer is discharged from the processing chamber 201. At this time, the valves 245c and 243c are kept open to maintain the supply of N2 gas to the processing chamber 201. The N2 gas acts as a purge gas, thereby improving the effect of discharging the gas remaining in the processing chamber 201 from the processing chamber 201.

[0147] [Step 2]

[0148] After step 1 is completed, NH 3 gas is supplied to the wafer 200 in the processing chamber 201, that is, the first layer formed on the wafer 200. The NH 3 gas is activated by heat and supplied to the wafer 200.

[0149] In this step, the opening and closing control of valves 245b, 243b, 245d, and 243d is performed in the same procedure as the opening and closing control of valves 245a, 243a, 245c, and 243c in step 1. The NH3 gas is flow-regulated by MFC241b, supplied to the processing chamber 201 through nozzle 230b, and exhausted from exhaust pipe 231. At this time, NH3 gas is supplied to the wafer 200. The NH3 gas supplied to the wafer 200 reacts with at least a portion of the first layer, i.e., the Si-containing layer, formed on the wafer 200 in step 1. As a result, the first layer is changed into the second layer, i.e., the silicon nitride layer (SiN layer) (modified) by non-plasma thermal nitridation.

[0150] After the second layer is formed, valves 245b and 243b are closed to stop the supply of NH3 gas. Then, the NH3 gas and reaction byproducts remaining in the processing chamber 201 that have not reacted or participated in the formation of the second layer are exhausted from the processing chamber 201 through the same processing steps as step 1. At this time, the gas remaining in the processing chamber 201 may not be completely exhausted as in step 1.

[0151] (Specified number of implementations)

[0152] By performing the above two steps non-simultaneously or asynchronously for a predetermined number of times (n), a SiN film of a predetermined thickness can be formed on the wafer 200. It should be noted that it is preferred that the thickness of the second layer (SiN layer) formed when the above cycle is performed once is smaller than the predetermined thickness and the above cycle is repeated a plurality of times until the thickness of the SiN film formed by stacking the second layer (SiN layer) reaches the predetermined thickness.

[0153] (Purge process)

[0154] After the film forming process is completed, valves 245c, 243c, 245d, 243d, 245g, and 243g are opened, and N2 gas is supplied to the processing chamber 201 from the gas supply pipes 230a, 230b, and 230c and exhausted from the exhaust pipe 231. N2 gas acts as a purge gas. Thus, the processing chamber 201 is purged, and the residual gas and reaction by-products in the processing chamber 201 are removed from the processing chamber 201 (purge). Afterwards, a process is performed in which the atmosphere of the processing chamber 201 is replaced with an inert gas (inert gas replacement) while the pressure in the processing chamber 201 is restored to normal pressure (atmospheric pressure recovery). The above-mentioned cleaning step is performed in parallel with the above-mentioned atmospheric pressure recovery step. The details of this cleaning step are described later.

[0155] (Boat unloading and wafer removal)

[0156] The cover 219 is lowered by the boat elevator 115, and the lower end of the processing tube 203 is opened. Then, the processed wafers 200 are carried out from the lower end of the processing tube 203 to the outside of the processing tube 203 while being supported by the boat 217 (boat unloading). The processed wafers 200 are taken out of the boat 217 (wafer taking out).

[0157] (6) Cleaning process

[0158] The cleaning process is performed to remove byproducts attached to components constituting the processing chamber 201. When the cleaning process is performed, the main control unit 25 executes a cleaning recipe stored in the program storage area 33 of the storage unit 28.

[0159] A method of cleaning the processing chamber 201 using a cleaning gas in the cleaning step of this embodiment will be described. Fluorine (F2) gas, hydrogen fluoride (HF) gas, or the like can be used as the cleaning gas.

[0160] Specifically, the lower end of the processing furnace 202 is blocked by the furnace gate when the empty boat 217 is carried into the processing chamber 201 or the boat 217 is not carried into the processing chamber 201. Then, the processing chamber 201 is vacuum-exhausted by the APC valve 242 to reach a predetermined cleaning pressure, and the processing chamber 201 is heated by the heater 206 to reach a predetermined cleaning temperature.

[0161] Then, while the processing chamber 201 is maintained at a predetermined cleaning temperature and a predetermined cleaning pressure, supply of the cleaning gas to the processing chamber 201 is started.

[0162] Specifically, when valves 243a to 243d, 243g, 243h, 245a to 245d, 245g, and 245h are closed to stop the supply of processing gas, reaction gas, and inactive gas to the processing chamber 201, valves 243e and 245e are opened to allow the cleaning gas to flow to the gas supply pipe 232e. In addition, the cleaning gas is flow-regulated by MFC241e, supplied to the processing chamber 201 via the nozzle 230c, and exhausted from the exhaust unit 310. At this time, valves 245f and 243f are closed. It should be noted that valves 245c, 243c, 245d, and 243d can also be opened at the same time to allow N2 gas to flow into the gas supply pipes 232a and 232b. The N2 gas is flow-regulated by MFC241c and 241d, supplied to the processing chamber 201 together with the cleaning gas, and exhausted from the exhaust pipe 231.

[0163] That is, the cleaning gas supplied to the processing chamber 201 rises in the processing chamber 201 and flows out from the upper end opening of the inner tube 204 into the cylindrical space 250, flows down in the cylindrical space 250, and is exhausted from the exhaust unit 310. When the cleaning gas passes through the processing chamber 201, it contacts the by-products attached to the processing chamber 201 and etches them away. When the removal of the by-products is completed after a preset processing time, the valves 245e and 243e are closed to stop the supply of the cleaning gas to the processing chamber 201.

[0164] (7) Exhaust cleaning process

[0165] In the exhaust cleaning process (cleaning step) of this embodiment, the atmosphere of the processing chamber 201 after the film forming process in the process is replaced with an inert gas (inert gas replacement), and as described later, Figure 6 As shown, in the process of returning the pressure in the processing chamber 201 to normal pressure (recovery to atmospheric pressure), the cleaning gas is supplied to the components constituting the exhaust unit 310 at a preset initial value. Figure 6 As shown, since the exhaust cleaning process is added to the process, the atmospheric pressure recovery process in the process is configured to be executed in parallel with the cleaning step. Thus, each time the process is executed, a predetermined amount (initial flow rate) of clean gas can be supplied to the components constituting the exhaust unit 310, so that by-products in the exhaust unit 310 can be removed. In addition, in the case where an abnormal tendency is detected at the components constituting the exhaust unit 310 during the process, the set flow rate of the clean gas can be changed from the initial value to supply the clean gas to the components constituting the exhaust unit 310.

[0166] In addition, the controller 240 in this embodiment, when detecting abnormal trends such as closure of the piping and stoppage of the pump caused by the attachment of byproducts to the components constituting the exhaust unit 310, issues an alarm and changes the set flow rate of the clean gas, that is, increases it. At this time, by setting an appropriate amount of clean gas corresponding to the number of occurrences of the alarm, the maintenance cycle of the components constituting the exhaust unit 310 is extended and the operating rate of the device is improved. In addition, compared with the case of implementing with a constant amount of clean gas, the total amount of clean gas in the cleaning step can be suppressed, and the byproducts can be removed before they accumulate in the exhaust pipe 231, the pump 244, the main pump (not shown) and other components constituting the exhaust unit 310.

[0167] Specifically, the main control unit 25 controls to obtain device data indicating the state of the exhaust unit 310 in a predetermined specific step during the execution of the process, and issues an alarm when an abnormal tendency (sign) in the exhaust unit 310 is detected based on the current value, rotation speed, and back pressure of the pump 244, and notifies the main device and the display unit 31. In addition, each time the number of alarms increases, the set flow rate of the cleaning gas increases. In other words, the main control unit 25 can change the set flow rate of the cleaning gas in accordance with the number of alarms, and automatically execute the cleaning step in parallel with the atmospheric pressure recovery process of the process according to the changed set flow rate of the cleaning gas.

[0168] For example, the main control unit 25 performs the exhaust cleaning process at the initial value of the cleaning gas flow rate in parallel with the atmospheric pressure recovery process after the film forming process. Figure 4 As shown, during the process execution, the device data consisting of the current value, rotation speed, and back pressure of the pump 244 are acquired, and when, for example, an abnormal tendency of blockage of the exhaust pipe 231 or clogging of the pump is detected during the film forming process, the main control unit 25 increases the flow rate of the cleaning gas to perform the exhaust cleaning process to prevent the device from stopping due to the blockage of the exhaust pipe 231 or the clogging of the pump. It should be noted that the acquisition of the device data consisting of the current value, rotation speed, and back pressure of the pump 244 is preferably performed in a process (such as a preparation step) in which the pump 244 is subjected to a load.

[0169] Here, use Figure 2 The exhaust cleaning process in the present embodiment is described. First, after the film forming process in the above-mentioned process is completed and the purge process is completed, an atmospheric pressure recovery process is performed. At this time, the main control unit 25 opens the valves 245c, 243c, 245d, 243d, 245g, and 243g, and supplies N2 gas from the gas supply pipes 230a, 230b, and 230c to the processing chamber 201. It should be noted that N2 gas can be supplied to the processing chamber 201 from any one of the gas supply pipes 230a, 230b, and 230c. At this time, the APC valve 242 becomes fully closed, and while the processing chamber 201 is made into an N2 gas atmosphere, it is gradually increased from the processing pressure (prescribed reduced pressure), and N2 gas is supplied until it becomes atmospheric pressure. It should be noted that the atmospheric pressure recovery process takes about several minutes, for example, 5 minutes.

[0170] Then, in parallel with the above-mentioned atmospheric pressure recovery process, the main control unit 25 opens valves 245f and 243f to allow the clean gas to flow to the gas supply pipe 232f while closing valves 245a, 243a, 245b, 243b, 245e, 243e, 245h, and 243h to stop the supply of the processing gas, the reaction gas, and the clean gas to the processing chamber 201 and the supply of the inactive gas to the exhaust unit 310. The clean gas is adjusted to, for example, a predetermined flow rate (initial flow rate) by MFC241f, and is supplied to the exhaust unit 310 while bypassing the processing chamber 201. It should be noted that the above-mentioned valve action remains unchanged even when the average value of the device data changes and an abnormality is detected, but the flow rate adjusted by MFC241f is different. Alternatively, the supply time may be changed without changing the flow rate adjusted by MFC241f.

[0171] That is, Figure 2 As shown, the cleaning gas is exhausted to the outside of the frame 111 via the gas supply pipe 232f and the exhaust pipe 231, the pump 244, the pressure sensor 247 and the main pump not shown. That is, when the cleaning gas passes through the exhaust unit 310, it contacts the by-products attached to the exhaust unit 310 and etches them away. If the pre-set processing time has passed and the removal of the by-products is completed, the valves 245f and 243f are closed to stop the supply of the cleaning gas to the exhaust unit 310. Here, the processing time is set to a time so that the exhaust cleaning process must end in the atmospheric pressure recovery process. In other words, the total time of the exhaust cleaning process is shorter than the total time of the atmospheric pressure recovery process. In addition, the start time of the atmospheric pressure recovery process is set to be earlier than the start time in the exhaust cleaning process, and the end time of the atmospheric pressure recovery process is set to be later than the end time in the exhaust cleaning process.

[0172] In addition, use Figure 5 to Figure 7 The exhaust gas cleaning process in this embodiment will be described specifically.

[0173] Figure 5 It is dedicated to Figure 2 FIG. 2 is a diagram of an exhaust system (exhaust line) in FIG. Here, it is configured so that a clean gas (e.g., F2 gas, HF gas, etc., which is a fluorine-containing gas) can be directly supplied from a clean gas supply source to an exhaust pipe 231 on the exhaust side of the APC valve 242 and the supply side of the pump 244 through a bypass line while the APC valve 242 is closed, bypassing the process chamber 201. Furthermore, a gas concentration detector (e.g., FT-IR) is provided on the exhaust pipe 231 on the exhaust side of the pump 244, which can detect at least the gas concentration in the exhaust pipe 231 when the clean gas is supplied.

[0174] Figure 6This is a diagram showing an example of adding an exhaust gas cleaning step to the atmospheric pressure recovery step of the process. Of course, the method of adding the exhaust gas cleaning step to the process in this embodiment is not limited to the above method.

[0175] like Figure 6 As shown, the configuration is such that the supply of the cleaning gas starts and ends within the atmospheric pressure recovery process. In addition, with this configuration, the exhaust cleaning process can be performed each time a process is performed.

[0176] Below, use Figure 5 , Figure 6 Explain the exhaust cleaning process. Figure 6 In the figure, the atmospheric pressure recovery process is divided into an atmospheric pressure recovery process 1 to an atmospheric pressure recovery process 4, but this is only for the sake of convenience in order to easily explain the exhaust gas cleaning process of the four steps.

[0177] First, when the atmospheric pressure recovery process begins, the APC valve 242 is closed (fully closed) and the valve 245e is closed. It should be noted that, in this embodiment, the APC valve 242 and the valve 245e are closed until the atmospheric pressure recovery process and the next boat unloading process are completed. At about the same time, the valve 243f is opened, and the exhaust pipe 231 on the exhaust side of the gas supply pipe 232f and the APC valve 242 is decompressed by the pump 244 (atmospheric pressure recovery process 1). In other words, this process is a process for decompressing and exhausting the gas supply pipe 232f and the exhaust pipe 231 as a preparation before supplying the clean gas, and it is performed for 1 minute in this embodiment. At this time, the valves 245h and 243h can also be set to open, and inactive gas is supplied from the purge gas supply source to the gas supply pipe 232f and the exhaust pipe 231 as a purge gas. It should be noted that the meaning of "at about the same time" not only refers to at the same time, but also means less than 1 second. In this case, it means that the opening of the valve 243f is slightly delayed because the pump 244 is always in action. It should be noted that, needless to say, when the atmospheric pressure recovery process starts, the valve 245f is in a closed state.

[0178] Next, while keeping the APC valve 242 closed, valves 245f and 243f are opened, and while the pressure is reduced by the pump 244, the clean gas whose flow rate is controlled by the MFC 241 is supplied to the gas supply pipe 232f and the exhaust pipe 231 on the exhaust side of the APC valve 242 (atmospheric pressure recovery process 2). Figure 5 In the state shown, the cleaning gas is supplied to the gas supply pipe 232f and the exhaust pipe 231 on the exhaust side of the APC valve 242. Figure 6The process is shown as a 10-minute process. The total time of the exhaust cleaning process is not a problem as long as it is shorter than the atmospheric pressure recovery process time, so it is of course not limited to the above time. In other words, 10 minutes is just an example. At this time, valves 245h and 243h can also be set to open, and purge gas can be supplied from the purge gas supply source to the gas supply pipe 232f and the exhaust pipe 231.

[0179] Here, during the supply step, the gas concentration in the exhaust pipe 231 is detected by a gas concentration detector provided on the exhaust side of the pump 244. The gas to be detected is set in advance according to the type of the cleaning gas.

[0180] Next, while the APC valve 242 is kept closed, the valve 245f is closed and the valve 243f is opened, and the pressure is reduced by the pump 244 to exhaust the clean gas in the gas supply pipe 232f and the exhaust pipe 231 on the exhaust side of the APC valve 242 (atmospheric pressure recovery process 3). In other words, this process is a process of decompressing and exhausting the gas supply pipe 232f and the exhaust pipe 231 in order to remove the residue and unreacted gas of the supplied clean gas, and in this embodiment, it is 2 minutes and 10 seconds. At this time, the valves 245h and 243h can also be opened to supply the purge gas from the purge gas supply source to the gas supply pipe 232f and the exhaust pipe 231.

[0181] While the APC valve 242 is still closed, a process of purging the gas supply pipe 232f and the exhaust pipe 231 on the exhaust side of the APC valve 242 with an inert gas is performed. Next, the valve 245f is kept closed, and the valves 245h and 243h are opened, and the purge gas is supplied from the purge gas supply source to the gas supply pipe 232f and the exhaust pipe 231, and the APC valve 242 is kept closed and 243f is opened, and the gas supply pipe 232f and the exhaust pipe 231 on the exhaust side of the APC valve 242 are exhausted by the pump 244 (atmospheric pressure recovery process 4). That is, this process is a purge process of supplying purge gas to the gas supply pipe 232f and the exhaust pipe 231 to purge the gas supply pipe 232f, the exhaust pipe 231 and the pump 244, respectively, and in this embodiment, it is performed for 1.5 minutes. The type of purge gas is not particularly limited as long as it is an inert gas.

[0182] It should be noted that, when the above-mentioned purging process is completed, valves 245f, 243f, 245h, and 243h are all closed, and the exhaust cleaning process is completed. Figure 6 In the process, the exhaust cleaning step and the atmospheric pressure recovery step are completed at approximately the same time, but the atmospheric pressure recovery step must be completed after the exhaust cleaning step is completed.

[0183] Here, a time is set for each process, but in practice, it is preferred that each process be completed before the set machine room.

[0184] On the other hand, as for the atmospheric pressure recovery process, since the APC valve 242 and the valve 245e are in a fully closed state, it is performed completely independently from the above-mentioned exhaust cleaning process. That is, the process of restoring the processing chamber 201 to atmospheric pressure and replacing it with an inert gas is performed in parallel and independently from the above-mentioned exhaust cleaning process. Here, for example, even if the atmospheric pressure is reached at the moment of the atmospheric pressure recovery process 2, the inert gas is stopped or the pressure regulator (not shown) is operated to exhaust the pressure of the processing chamber 201 through the pressure regulator to finely adjust the pressure of the processing chamber 201 so as to prevent the processing chamber 201 from being over-pressurized, so it will not be a problem even if the APC valve 242 is fully closed.

[0185] Figure 7 The cumulative film thickness is 6 nm. Figure 6 Here, an experimental example of a case where HF gas as gas A is used as the cleaning gas and 2 L is supplied in 10 minutes is shown. Figure 7 , so that the concentration of the by-product gas B, i.e., SiF4 gas, is reduced to nearly 0 ppm in about 4 minutes, and the removal of the by-product can be confirmed by the concentration of SiF4 gas in the gas concentration detector. In this way, the exhaust cleaning step is added to the process, and the clean gas is supplied to the exhaust pipe 231 and the pump 244 under this condition every time the process is executed, so that the maintenance cycle (maintenance period) of the pump 244 can be increased by more than 2 times.

[0186] In the case of the above experimental example, the clean gas is supplied to the exhaust pipe 231 and the pump 244 in a state without byproducts for about 6 minutes, but the maintenance cycle of the pump 244 can be increased by more than 2 times, and if the cleaning conditions can be changed, further improvement in the maintenance cycle can be expected. For example, in the case of the above experimental example, if the flow rate of the clean gas can be reduced from 2L to 1L or the time for supplying the clean gas can be shortened from 10 minutes to 5 minutes, the maintenance cycle of the pump 244 can be further improved. In this way, if the cleaning conditions can be changed, further effects can be expected.

[0187] Next, based on Figure 8 to Figure 10 The execution operation of the exhaust cleaning process by the controller 240 will be described. The main control unit 25 is configured to Fig.10 The atmospheric pressure recovery process shown in FIG. 1 is performed in parallel with the exhaust cleaning process. Fig.10 As shown, only different gases are supplied, that is, the cleaning gas is supplied in the exhaust cleaning process and the inert gas is supplied in the purge process, and the back pressure of the auxiliary pump is made substantially the same pressure by vacuum suction by the main pump (not shown).

[0188] In the process, in the preparation step of vacuum suction from atmospheric pressure, the back pressure of the pump 244 rises suddenly, and a load is applied to the pump 244. The following describes an example in which the preparation step is set as the above-mentioned specific step.

[0189] like Figure 8 As shown, the main control unit 25 acquires device data during the process execution from the start of the process (step S10). Specifically, as device data, data indicating the current value, rotation speed, and back pressure of the pump 244 during the process execution are acquired at least at predetermined intervals.

[0190] Then, it is determined whether the process being executed is a specific step set in advance (step S11). Fig.10 The preparation process (Slow Pump process) shown.

[0191] If it is determined to be a non-specific step ("No" in step S11), the process returns to step S10. If it is determined to be a specific step ("Yes" in step S11), the device data acquired at a predetermined interval in the specific step is added (step S12). It should be noted that only the device data in the specific step may be acquired.

[0192] In addition, it is determined whether the specific step has been completed (step S13). When it is determined that the specific step has not been completed ("No" in step S13), the process returns to step S11.

[0193] When it is determined that the specific step is completed ("Yes" in step S13), the main control unit 25 calculates the average value of the device data obtained by addition and stores it in the storage unit 28 (step S14). Specifically, the current value, rotation speed and back pressure of the pump 244 in the preparation process are acquired in a cycle of, for example, 1 second and added respectively. Then, the cumulative value of the added data is divided by the number of additions, and the average value is calculated and stored in the storage unit 28.

[0194] Then, the main control unit 25 compares the average value of the data calculated this time with the average value of the data calculated when the previous process was executed (step S15). Specifically, the average values ​​of the current value, rotation speed and back pressure of the pump 244 in the current preparation process are compared with the average values ​​of the current value, rotation speed and back pressure of the auxiliary pump 244 in the preparation process of the previous process.

[0195] Then, the monitoring parameters stored in the storage unit 28 are checked. If it is determined that the average value of this time has not increased (or decreased) relative to the previous average value (no abnormal trend) ("No" in step S15), the continuous number counter that counts the continuous number of abnormal trends is cleared (set to 0) (step S19), and the processing ends. Specifically, if it is determined whether the average value of the current value of the pump 244 in the preparation process has increased relative to the average value of the current value of the pump 244 in the preparation process of the previous process and it is determined that it has not increased, the continuous number counter is cleared. In addition, the average value of the rotation speed of the pump 244 and the average value of the back pressure of the pump 244 are also compared in the same way.

[0196] And, when it is determined that the current average value has increased (decreased) relative to the previous average value (there is an abnormal tendency) ("Yes" in step S15), the continuous number counter starts counting (counter increment) (step S16). Then, it is determined whether it has continuously increased (or decreased) a preset number of times (step S17).

[0197] If it is determined that the flow rate has not continuously increased (decreased) (there is no abnormal tendency) for a preset number of times ("No" in step S17), the process is terminated. If it is determined that the flow rate has continuously increased (decreased) (there is an abnormal tendency) for a preset number of times ("Yes" in step S17), the cleaning gas set flow rate change process described later is performed (step S18). Then, the continuous number counter is cleared (S19), and the process is terminated.

[0198] Specifically, when it is determined that the average value of the current value of the pump 244 in the preparation process has increased relative to the average value of the current value of the pump 244 obtained when the previous process was executed, the counting of the continuous number counter is started, and when the current value of the pump 244 has an increasing trend for a predetermined number of times, for example, 5 times in a row, which is the setting value of the monitoring parameter, an alarm is issued, and the set flow rate of the cleaning gas in the exhaust cleaning process is changed. For example, when the average value of the current value of the pump 244 in the preparation process increases for 5 consecutive times (rotation speed 6.879 krpm, back pressure 1.000 kPa), such as 14.421A for the 47th batch, 14.528A for the 48th batch, 14.596A for the 49th batch, 14.660A for the 50th batch, and 15.063A for the 51st batch), an alarm is issued, and the set flow rate of the cleaning gas in the exhaust cleaning process is changed. It should be noted that it is not limited to this number, and it can be configured as long as the trend of the monitoring parameter can be captured, for example, it is set to 3 times or more and 7 times or less.

[0199] In addition, similarly, for the average value of the back pressure of the pump 244 and the average value of the rotation speed of the pump 244 in the preparation process, when the set value as the monitoring parameter shows a trend pre-defined as an abnormal trend for a specified number of consecutive times, an alarm is issued and the set flow rate of the cleaning gas in the exhaust cleaning process is changed.

[0200] That is, at least any one of the average values ​​of the current value, rotational speed and back pressure of the pump in the preparation process is compared with the average values ​​of the current value, rotational speed and back pressure of the pump in the previous preparation process. When an increase or decrease pre-defined as an abnormal trend occurs continuously for a pre-set number of times, an abnormal tendency of closure of the piping constituting the exhaust unit 310 or pump stop is detected and an alarm is issued, and the set flow rate of the cleaning gas in the exhaust cleaning process is changed.

[0201] It should be noted that in the present embodiment, an example of changing the set flow rate of the clean gas in the exhaust cleaning process is described when at least one of the average values ​​of the current value, rotation speed, and back pressure of the pump 244 continuously increases or decreases by a predetermined number of times relative to the previous average value, but it is not limited to this. It can also be configured to issue an alarm when the average values ​​of the current value, rotation speed, and back pressure of the pump 244 continuously increase or decrease by a predetermined number of times relative to the previous average value, or issue an alarm when any two or more (multiple) of the average values ​​of the current value, rotation speed, and back pressure of the pump 244 continuously increase or decrease by a predetermined number of times relative to the previous average value, and change the set flow rate of the clean gas in the exhaust cleaning process. In addition, it is also possible to issue an alarm when the average value of at least one device data in the group consisting of the current value, rotation speed, and back pressure of the pump 244 continuously deviates from the threshold value by a predetermined number of times, and change the set flow rate of the clean gas in the exhaust cleaning process. In addition, it is also possible to issue an alarm when the average value of each device data in the current value, rotation speed, and back pressure of the pump 244 continuously deviates from the threshold value by a predetermined number of times, and change the set flow rate of the clean gas in the exhaust cleaning process. With these configurations, it is possible to grasp the tendency of device data in the exhaust device, and detect the tendency of abnormality of components constituting the exhaust unit 310 .

[0202] Next, use Fig. 9 (A) and Fig. 9 (B) explains the cleaning gas set flow rate change process in step S18 described above. The cleaning gas set flow rate change process is changed according to the number of occurrences of the alarm in which the abnormal tendency is detected.

[0203] First, if the main control unit 25 detects an abnormal tendency of the exhaust unit 310, an alarm is issued (step S20). Then, the alarm counter for counting the number of alarm occurrences is added (step S21). The alarm is issued by displaying the content of the signs of the closure of the pipe and the blockage of the pump on the display unit, prompting the maintenance of the exhaust unit 310, and notifying these messages to the main device. Then, it is determined whether the added alarm counter is a preset limit number of times (step S22). Then, when the alarm counter reaches the limit number of times ("yes" in step S22), a final warning of the closure of the exhaust pipe and the blockage of the pump is issued (step S25) and the processing is terminated. As a final warning, the display unit displays that the next process is prohibited, and maintenance such as replacement and inspection of the exhaust device should be carried out as soon as possible, or a message is notified to the main device. That is, when the abnormality of the device data exceeds the threshold, a final warning prohibiting the execution of the next process is issued. And, after the maintenance is implemented, the alarm counter is reset. In addition, the set flow rate of the clean gas in the exhaust cleaning process returns to the initial value.

[0204] In addition, when the alarm counter has not reached the limit number of times ("No" in step S22), the set flow rate information of the cleaning gas is obtained from the storage unit 28 based on the alarm counter (the number of times the alarm occurs) (step S23). It should be noted that the flow rate of the cleaning gas corresponding to the alarm counter is stored in the storage unit 28 in advance. Then, the set flow rate of the cleaning gas in the exhaust cleaning process is changed (step S24), and the processing is terminated. It should be noted that the main control unit 25 is in the next step from the preparation process to the next step. Fig.10 In the step before the atmospheric pressure recovery step shown, the change in the average value of the acquired device data is determined. Therefore, in this embodiment, the exhaust cleaning step can be executed in parallel with the atmospheric pressure recovery step of the process recipe.

[0205] When an abnormal tendency of the device data is detected in this way, the flow rate of the cleaning gas and / or the supply time of the cleaning gas are changed during the execution of the process, thereby changing the set flow rate of the cleaning gas to correct the exhaust cleaning process, and the exhaust cleaning process can be executed by the corrected exhaust cleaning process (the changed set flow rate of the cleaning gas). As a result, the byproducts attached to the exhaust device can be removed at an appropriate time with an appropriate amount of cleaning gas, thereby suppressing the total amount of cleaning gas while avoiding the closure of the exhaust pipe and the stop of the pump rotor caused by the clogging of the pump, and the process can be continuously executed to improve the device operation rate.

[0206] (8) Effects of this embodiment

[0207] According to the present embodiment, one or more of the following effects can be obtained.

[0208] (a) By adding the exhaust cleaning step to the process, a cleaning gas at a preset flow rate can be supplied after each film forming process in the process, and by-products can be removed before they accumulate in the exhaust device.

[0209] (b) By performing the exhaust cleaning step in parallel with the atmospheric pressure recovery step after each film formation process in the process, byproducts adhering to the exhaust device can be removed at an appropriate timing, thereby improving the operating rate of the device.

[0210] (c) By efficiently capturing the trend of the parameter of the monitoring object related to the exhaust device to detect abnormality and increasing the set flow rate of the clean gas when the abnormality is detected, maintenance can be reliably performed before the abnormality occurs, thereby improving the operation rate of the device.

[0211] (d) By capturing the trend of monitoring parameters related to the exhaust system, it is possible to detect clogging caused by byproducts adhering to the exhaust system before the exhaust pipe is blocked or before the pump is clogged and the pump rotor stops, for example.

[0212] (e) It is possible to capture the sign of abnormality of the exhaust device to be monitored, and inform the user of the sign of blockage of the exhaust pipe or stop of the pump rotor due to pump blockage by issuing an alarm, displaying a message on the display unit 31, displaying the content of the alarm on the display unit 31, or notifying the main device of the message. Thus, it is possible to reliably perform maintenance such as replacement and inspection of the components constituting the exhaust device before the exhaust pipe is blocked or the pump rotor stops due to pump blockage.

[0213] (f) During the execution of the process, a clean gas can be supplied to the exhaust part to remove by-products in the exhaust device by bypassing the processing chamber. There is no need to perform pre-treatment processes such as pre-coating after the previous cleaning process is completed and before the process is restarted. Therefore, the device operation rate can be significantly improved.

[0214] (g) The average value of the device data in a pre-set specific step among each step constituting the process is compared with the average value of the device data in the specific step calculated when the process was previously executed, thereby detecting the blockage of the exhaust pipe and the sign of the pump rotor stopping due to the blockage of the pump, so that the threshold value may not be set before the final warning.

[0215] Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the gist of the present invention.

[0216] In addition, in the above embodiment, an example of film formation on the wafer 200 is described. However, the present invention is not limited to such a method. For example, in the above embodiment, a cleaning process in which a cleaning gas such as a halogen gas is supplied is described, but a purge gas process in which a purge gas such as an inert gas is supplied may also be used. In addition, a fluorine-containing gas is described as a halogen gas, but a chlorine-containing gas may also be used.

[0217] Furthermore, when a component constituting the exhaust unit 310 tends to be abnormal, the concentration or gas type of the cleaning gas in the exhaust cleaning step may be changed.

[0218] In addition, the flow rate of the cleaning gas may be set to a preset initial value and supplied to the components constituting the exhaust unit 310 during wafer removal after the atmospheric pressure recovery step and wafer filling in the next process.

[0219] In addition, in the above embodiment, an example of film formation using a batch type processing device as a vertical device that processes a plurality of substrates at a time is described, but the present invention is not limited thereto. In addition, in the above embodiment, an example of film formation using a substrate processing device having a hot wall type processing furnace is described, but the present invention is not limited thereto and is preferably applied when a thin film is formed using a substrate processing device having a cold wall type processing furnace.

[0220] Furthermore, the present invention is not limited to semiconductor manufacturing equipment that processes semiconductor wafers such as the substrate processing equipment of the present embodiment, and can also be applied to LCD (Liquid Crystal Display) manufacturing equipment that processes glass substrates.

Claims

1. A gas supply method comprising: a substrate processing step of processing a substrate while operating a valve provided in an exhaust pipe to maintain a processing pressure in a processing chamber; and a preparation step of adjusting the processing chamber to the processing pressure before the substrate processing step. In the preparation process, data of the exhaust device associated with the exhaust of the processing chamber is obtained, and changes in the data of the exhaust device are monitored. When the data of the exhaust device changes continuously for multiple times and is determined to be an abnormal trend, the supply amount of the specified gas directly supplied to the downstream of the valve is adjusted according to the changes in the data of the exhaust device.

2. The gas supply method according to claim 1, wherein: The method further comprises a step of restoring the processing chamber from the processing pressure to the atmospheric pressure. The configuration is such that the time for supplying the predetermined gas is shorter than the total time of the atmospheric pressure recovery step.

3. The gas supply method according to claim 1, wherein: The atmospheric pressure recovery step is started earlier than the supply of the predetermined gas.

4. The gas supply method according to claim 1, wherein: When the predetermined gas is supplied, the valve is configured to be closed.

5. The gas supply method according to claim 1, wherein: The predetermined gas is configured to be different in type from the gas used in the atmospheric pressure restoring step.

6. The gas supply method according to claim 1, wherein: The specified gas is a cleaning gas or a purge gas.

7. The gas supply method according to claim 6, wherein: The cleaning gas is a halogen-containing gas or a chlorine-containing gas.

8. The gas supply method according to claim 6, wherein: The purge gas is an inactive gas.

9. The gas supply method according to claim 1, wherein: The concentration of the predetermined gas is configured to be changeable.

10. The gas supply method according to claim 1, wherein: The supply step is configured to be performed every time the substrate processing step is performed.

11. The gas supply method according to claim 1, wherein: If an abnormality occurs in the exhaust device data during the preparation process, If it is less than the preset number, the supply amount of the specified gas remains unchanged. If the abnormality occurs continuously a preset number of times, the supply amount of the predetermined gas is adjusted.

12. The gas supply method according to claim 11, wherein: The data related to the exhaust device is one or more of a current value, a rotation speed, and a back pressure of the exhaust device.

13. The gas supply method according to claim 11, further comprising: a step of accumulating the data related to the exhaust device collected in the preparation step; and A process for determining a change in the average value of the acquired data associated with the exhaust device is performed by calculating the average value of the acquired data associated with the exhaust device based on the accumulated data associated with the exhaust device, and comparing the calculated average value with the average value of the data associated with the exhaust device in the preparation step calculated when executing the previous process. 14 . The gas supply method according to claim 13 , further comprising: modifying the supply step by changing a flow rate of the predetermined gas and / or a time for flowing the predetermined gas, thereby changing the supply amount of the predetermined gas. 15 . The gas supply method according to claim 13 , further comprising a configuration in which the gas type of the predetermined gas is changed according to a change in data related to the exhaust device. 16 . A method for manufacturing a semiconductor device, comprising the gas supply method according to claim 1 .

17. A computer-readable recording medium having a program for causing a controller to cause a substrate processing apparatus to execute a process recipe, the process recipe comprising at least a substrate processing step of processing a substrate while operating a valve provided in an exhaust pipe to maintain a process pressure in a process chamber, and a preparation step of adjusting the process chamber to the process pressure before the substrate processing step. In the preparation process, data of the exhaust device associated with the exhaust of the processing chamber is obtained, and changes in the data of the exhaust device are monitored. When the data of the exhaust device changes continuously for multiple times and is determined to be an abnormal trend, the supply amount of the specified gas directly supplied to the downstream of the valve is adjusted according to the changes in the data of the exhaust device.

18. A substrate processing apparatus comprising: a processing chamber for processing a substrate; a supply unit for supplying a predetermined gas; and a control unit configured to execute: a substrate processing step of processing a substrate while operating a valve provided in an exhaust pipe to maintain a processing pressure in a processing chamber, and a preparation step of adjusting the processing chamber to the processing pressure before the substrate processing step, The control unit is configured to obtain data of an exhaust device associated with exhaust of the processing chamber during the preparation process, monitor changes in the data of the exhaust device, and, when the data of the exhaust device changes continuously for multiple times and is determined to be an abnormal trend, adjust the supply amount of a specified gas directly supplied downstream of the valve according to the changes in the data of the exhaust device.

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