Method for manufacturing semiconductor device, substrate processing apparatus, substrate processing method, and recording medium

Abstract

The present invention includes (a) a process of supplying a processing gas to a substrate arranged in a processing chamber to process the substrate, and (b) a process of supplying a cleaning gas to the processing chamber to remove deposits adhering to components in the processing chamber, and makes a period T2 from when the execution of (b) is completed to when the execution of (a) is started for the n+1th time shorter than a period T1 from when the execution of (a) for the nth time is completed to when the execution of (b) is started.

Description

Technical Field

[0001] This disclosure relates to methods for manufacturing semiconductor devices, substrate processing apparatus, substrate processing methods, and recording media. Background Technology

[0002] As a step in the manufacturing process of semiconductor devices, a process is sometimes performed where a processing gas is supplied to a substrate disposed in a processing chamber to process the substrate. After this process is performed multiple times, resulting in deposits adhering to components in the processing chamber, cleaning is sometimes performed at a predetermined time (see, for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-243677 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] The purpose of this disclosure is to ensure consistent substrate processing quality across different substrate processing processes.

[0008] Methods for solving problems

[0009] According to one aspect of this disclosure, the following technologies are provided, including:

[0010] (a) A step of processing the substrate by supplying processing gas to the substrate disposed in the processing chamber; and,

[0011] (b) A process of supplying clean gas to the aforementioned processing chamber to remove deposits adhering to the components within the aforementioned processing chamber.

[0012] Wherein, the period T2 from the completion of the execution of (b) above to the start of the execution of (a) above for the (n+1)th time is shorter than the period T1 from the completion of the execution of (a) above for the nth time to the start of the execution of (b) above.

[0013] The effects of the invention

[0014] According to this disclosure, it is possible to ensure consistent substrate processing quality between substrate processing processes. Attached Figure Description

[0015] [ Figure 1 [This is a schematic diagram of a vertical processing furnace of a substrate processing apparatus preferred in one embodiment of the present disclosure, and is a diagram showing the furnace portion in longitudinal section.]

[0016] [ Figure 2[This is a schematic diagram of a vertical processing furnace of a substrate processing apparatus preferred in one embodiment of this disclosure, and is based on...] Figure 1 The AA-line cross-sectional view shows the processing furnace section.

[0017] [ Figure 3 [This is a schematic diagram of the controller of a substrate processing apparatus preferred in one embodiment of the present disclosure, and a block diagram showing the control system of the controller.]

[0018] [ Figure 4 [A diagram illustrating the details of the processing steps within a processing chamber in one embodiment of this disclosure.]

[0019] [ Figure 5 (a) is a graph showing the temperature changes in a processing room in one embodiment of this disclosure, and (b) is a graph showing the temperature changes in a processing room in a reference example. Detailed Implementation

[0020] <One way of publishing this text>

[0021] The following mainly uses Figures 1-5 Chinese figure (a) illustrates one way of presenting this disclosure.

[0022] (1) Composition of substrate processing device

[0023] like Figure 1 As shown, the processing furnace 202 has a heater 207 as a heating mechanism (temperature control unit). The heater 207 is cylindrical and is vertically mounted by being supported on a retaining plate. The heater 207 also functions as an activation mechanism (activation unit) that uses heat to activate (excite) the gas.

[0024] Inside the heater 207, a reaction tube 203 is arranged concentrically with the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed into a cylindrical shape that is closed at the top and open at the bottom. Below the reaction tube 203, a manifold 209 is arranged concentrically with the reaction tube 203. The manifold 209 is made of a metal material such as stainless steel (SUS) and is formed into a cylindrical shape that is open at both the top and bottom. The upper end of the manifold 209 is configured to engage with the lower end of the reaction tube 203, supporting the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a sealing component. The reaction tube 203 is also vertically mounted, just like the heater 207. The processing container (reaction container) is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed in the hollow portion of the processing container. The processing chamber 201 is configured to accommodate a wafer 200, which serves as a substrate. Processing of the wafer 200 is performed within the processing chamber 201.

[0025] Inside the processing chamber 201, nozzles 249a and 249b, serving as the first and second supply units respectively, are each installed through the side wall of the manifold 209. Nozzles 249a and 249b are also referred to as the first nozzle and the second nozzle, respectively. Nozzles 249a and 249b are each made of a non-metallic material such as quartz or SiC, which are heat-resistant. Nozzles 249a and 249b are configured as shared nozzles for supplying multiple gases.

[0026] Gas supply pipes 232a and 232b, serving as first and second piping respectively, are connected to nozzles 249a and 249b. Gas supply pipes 232a and 232b are configured as shared piping for supplying multiple gases. Mass flow controllers (MFCs) 241a and 241b, serving as flow controllers (flow control units), and valves 243a and 243b, serving as on / off valves, are sequentially installed on gas supply pipes 232a and 232b, starting from the upstream side of the gas flow. Gas supply pipes 232c and 232d are connected to gas supply pipe 232a downstream of valve 243a. MFCs 241c and 241d, and valves 243c and 243d, are sequentially installed on gas supply pipes 232c and 232d, starting from the upstream side of the gas flow. Gas supply pipe 232e is connected to gas supply pipe 232b downstream of valve 243b. On the gas supply pipe 232e, MFC 241e and valve 243e are sequentially installed from the upstream side of the gas flow. The gas supply pipes 232a to 232e are made of metal materials such as SUS.

[0027] like Figure 2As shown, nozzles 249a and 249b are respectively provided vertically from the lower part of the inner wall of the reaction tube 203 towards the arrangement direction of the wafer 200 in a ring-shaped space between the inner wall of the reaction tube 203 and the wafer 200 in a top view. That is, nozzles 249a and 249b are respectively provided along the wafer arrangement area, in the area that horizontally surrounds the wafer arrangement area on the side of the wafer arrangement area where the wafer 200 is arranged. Gas supply holes 250a and 250b are respectively provided on the side of the nozzles 249a and 249b. Each gas supply hole 250a and 250b opens towards the center of the wafer 200 in a top view, and can supply gas to the wafer 200. Multiple gas supply holes 250a and 250b are provided in the area from the lower part to the upper part of the reaction tube 203.

[0028] A silane-based gas, such as silicon (Si), which is the main element constituting the film formed on the wafer 200, is supplied as a processing gas (raw material gas) from the gas supply pipe 232a through MFC 241a, valve 243a, and nozzle 249a into the processing chamber 201. The term "raw material gas" refers to a raw material in a gaseous state, such as a gas obtained by vaporizing a raw material that is liquid at room temperature and pressure, or a raw material that is gaseous at room temperature and pressure.

[0029] A gas, such as a fluorine-based gas, is supplied as a cleaning gas to the processing chamber 201 from the gas supply pipe 232b via MFC 241b, valve 243b, and nozzle 249b.

[0030] A nitrogen oxide-based gas, for example, is supplied as an additive gas to the treatment chamber 201 via gas supply pipe 232c, MFC 241c, valve 243c, gas supply pipe 232a, and nozzle 249a. The nitrogen oxide-based gas itself does not exert a cleaning effect, but it works by reacting with fluorine-based gases to generate active species such as halonitrosyl compounds, thereby enhancing the cleaning effect of the fluorine-based gases.

[0031] Nitrogen (N2) gas, for example, is supplied as an inactive gas from gas supply pipes 232d and 232e via MFCs 241d and 241e, valves 243d and 243e, gas supply pipes 232a and 232b, and nozzles 249a and 249b to the processing chamber 201. The N2 gas functions as a purge gas, carrier gas, dilution gas, etc.

[0032] The main components of the gas supply system (raw material gas supply system) consist of gas supply pipe 232a, MFC 241a, and valve 243a. The main components of the clean gas supply system consist of gas supply pipe 232b, MFC 241b, and valve 243b. The main components of the additive gas supply system consist of gas supply pipe 232c, MFC 241c, and valve 243c. The main components of the inactive gas supply system consist of gas supply pipes 232d and 232e, MFC 241d and 241e, and valves 243d and 243e.

[0033] Any or all of the aforementioned supply systems can be configured as an integrated supply system 248, which integrates valves 243a-243e, MFCs 241a-241e, etc. The integrated supply system 248 is configured such that it is connected to each of the gas supply pipes 232a-232e, and the supply of various gases into the gas supply pipes 232a-232e is controlled by the controller 121 (described later), i.e., by the opening and closing of valves 243a-243e and the flow regulation of MFCs 241a-241e, etc. The integrated supply system 248 is configured as an integral or separate integrated unit, and is configured such that it can be disassembled and assembled relative to the gas supply pipes 232a-232e, etc., and that the integrated supply system 248 can be maintained, replaced, or added to in an integrated unit manner.

[0034] An exhaust port 231a is provided below the side wall of the reaction tube 203 to exhaust the atmosphere of the processing chamber 201. The exhaust port 231a may also be provided from the lower part of the side wall of the reaction tube 203 along the upper part, that is, along the wafer arrangement area. An exhaust pipe 231 is connected to the exhaust port 231a. The exhaust pipe 231 is made of a metal material such as SUS. A vacuum pump 246, which is a vacuum exhaust device, is connected to the exhaust pipe 231 via a pressure sensor 245, which is a pressure detector (pressure detection unit) for detecting the pressure of the processing chamber 201, and an APC (Auto Pressure Controller) valve 244, which is a pressure regulator (pressure regulating unit). The APC valve 244 is configured to open and close the valve while the vacuum pump 246 is operating, thereby enabling vacuum exhaust and vacuum exhaust stop of the processing chamber 201. Furthermore, it is configured to adjust the pressure of the processing chamber 201 by adjusting the valve opening based on the pressure information detected by the pressure sensor 245 while the vacuum pump 246 is operating. The exhaust system mainly consists of an exhaust pipe 231, an APC valve 244, and a pressure sensor 245. Alternatively, a vacuum pump 246 could be included in the exhaust system.

[0035] Below the manifold 209, a sealing cover 219, serving as a furnace opening cover, is provided to airtightly seal the lower opening of the manifold 209. The sealing cover 219 is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220b, serving as a sealing component, is provided on the upper surface of the sealing cover 219 and abuts against the lower end of the manifold 209. Below the sealing cover 219, a rotation mechanism 267 is provided to rotate the crystal boat 217 (described later). The rotation shaft 255 of the rotation mechanism 267, made of a metal material such as SUS, passes through the sealing cover 219 and is connected to the crystal boat 217. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the crystal boat 217. The sealing cover 219 is configured to move vertically upwards and downwards via a crystal boat lift 115, which is a lifting mechanism located outside the reaction tube 203. The crystal boat lift 115 is configured as a transport system (transport mechanism) which moves the wafer 200 into the processing chamber 201 and moves the wafer 200 out of the processing chamber 201 by raising and lowering the sealing cover 219.

[0036] Below the manifold 209, a gate 219s serving as a furnace opening cover is provided. This gate 219s can airtightly seal the lower opening of the manifold 209 after the sealing cover 219 has been lowered and the crystal boat 217 has been removed from the processing chamber 201. The gate 219s is made of a metal material such as SUS and is formed in a disc shape. On the upper surface of the gate 219s, an O-ring 220c serving as a sealing component is provided, which abuts against the lower end of the manifold 209. The opening and closing actions (lifting, rotating, etc.) of the gate 219s are controlled by the gate opening and closing mechanism 115s.

[0037] The crystal boat 217, serving as a substrate support, is configured to hold multiple wafers 200, for example, 25 to 200 wafers 200 arranged horizontally with their centers aligned in the vertical direction and supported in a multi-layered manner, i.e., arranged with gaps between them. The crystal boat 217 is made of a heat-resistant material such as quartz or SiC. A heat-insulating plate 218, also made of a heat-resistant material such as quartz or SiC, is supported in multiple layers at the bottom of the crystal boat 217.

[0038] A temperature sensor 263, serving as a temperature detector, is installed inside the reaction tube 203. By adjusting the energization to the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature of the processing chamber 201 is adjusted to achieve the desired temperature distribution. The temperature sensor 263 is disposed along the inner wall of the reaction tube 203.

[0039] like Figure 3As shown, the controller 121, which serves as the control unit (control means), is configured as a computer equipped with a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, storage device 121c, and I / O port 121d are configured to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122, such as a touch panel, is connected to the controller 121.

[0040] The storage device 121c is configured with, for example, flash memory or an HDD (Hard Disk Drive). The storage device 121c stores, in a readable manner, a control program that controls the operation of the substrate processing apparatus, a process flow describing the film formation steps and conditions (described later), and a cleaning process describing the cleaning steps and conditions (described later). The process flow is a combination of methods that cause the controller 121 to execute each step in the film formation process (described later) and obtain a predetermined result, and functions as a program. The cleaning process is a combination of methods that cause the controller 121 to execute each step in the cleaning process (described later) and obtain a predetermined result, and functions as a program. Hereinafter, the process flow, cleaning process, control program, etc., will all be referred to as a program. Additionally, the process flow and cleaning process will be referred to as a process. In this specification, the term "program" is used in cases where only a process is included, cases where only a control program is included, or cases where both are included. RAM 121b is configured as a storage area (working area) for temporarily holding programs, data, etc., read by the CPU 121a.

[0041] I / O port 121d is connected to the aforementioned MFC241a~241e, valves 243a~243e, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotating mechanism 267, crystal boat elevator 115, gate opening and closing mechanism 115s, etc.

[0042] CPU 121a is configured to read and execute control programs from storage device 121c, and to read processes from storage device 121c based on inputs such as operation commands from input / output device 122. CPU 121a is configured to control the following actions according to the read processes: flow regulation of various gases using MFCs 241a-241e, opening and closing of valves 243a-243e, opening and closing of APC valve 244 and pressure regulation using APC valve 244 based on pressure sensor 245, starting and stopping of vacuum pump 246, temperature regulation of heater 207 based on temperature sensor 263, rotation and rotation speed regulation of crystal boat 217 using rotating mechanism 267, lifting and lowering of crystal boat 217 using crystal boat elevator 115, opening and closing of gate 219s using gate opening and closing mechanism 115s, etc.

[0043] The controller 121 is configured to install the aforementioned program stored in the external storage device 123 into a computer. The external storage device 123 includes, for example, a hard disk such as an HDD, an optical disk such as a CD, a CD-ROM such as an MO disk, or a semiconductor memory such as a USB flash drive. The storage device 121c and the external storage device 123 are configured in the form of a recording medium that can be read by a computer. Hereinafter, they will also be referred to collectively as recording media. In this specification, the term "recording medium" is used in cases where only the storage device 121c is included, cases where only the external storage device 123 is included, or cases where both are included. It should be noted that providing a program to a computer may also be done without using the external storage device 123, but using communication means such as the Internet or a dedicated line.

[0044] (2) Substrate processing process

[0045] An example of a substrate processing sequence will be described, which is a step in the manufacturing process of a semiconductor device, in which the substrate processing apparatus described above is used to process the wafer 200 by supplying processing gas into a processing container containing the wafer 200 as a substrate. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

[0046] In this specification, the term "wafer" is used to refer to both the wafer itself and a laminate of the wafer and a specified layer or film formed on its surface. The term "surface of the wafer" is used to refer to both the surface of the wafer itself and the surface of a specified layer or film formed on the wafer. The phrase "forming a specified layer on the wafer" includes both forming the specified layer directly on the surface of the wafer itself and forming the specified layer on top of a layer or film formed on the wafer. The term "substrate" is used in the same way as "wafer."

[0047] [Substrate treatment]

[0048] Here, as an example of substrate processing, a film formation process is described in which a film formation raw material gas, which is supplied as a processing gas, to the wafer 200 to form a film on the wafer 200.

[0049] (Wafer filling, crystal boat loading)

[0050] If multiple wafers 200 are loaded (wafer filling) into the crystal boat 217, the gate opening and closing mechanism 115s moves the gate 219s, opening the lower end of the current collector 209 (gate opening). Then, as... Figure 1 As shown, a crystal boat 217 supporting multiple wafers 200 is lifted by a crystal boat lift 115 and moved into the processing chamber 201 (crystal boat loading). In this state, the sealing cover 219 seals the lower end of the manifold 209 by means of an O-ring 220b.

[0051] (Pressure and temperature regulation)

[0052] After the crystal boat 217 is moved into the processing chamber 201, vacuum pump 246 is used to perform vacuum exhaust (pressure reduction exhaust) to bring the processing chamber 201, i.e., the space where the wafer 200 exists, to the desired pressure (vacuum level). At this time, the pressure of the processing chamber 201 is measured by pressure sensor 245, and the APC valve 244 is controlled by feedback (pressure regulation) based on the measured pressure information. In addition, the wafer 200 in the processing chamber 201 is heated by heater 207 to bring it to the desired temperature. At this time, the power supply to heater 207 is controlled by feedback (temperature regulation) based on the temperature information detected by temperature sensor 263 to bring the processing chamber 201 to the desired temperature distribution. In addition, the rotation of crystal boat 217 and wafer 200 using rotation mechanism 267 is started. The operation of vacuum pump 246, heating of wafer 200, and rotation are all carried out continuously at least until the processing of wafer 200 is completed.

[0053] (film formation)

[0054] After the pressure and temperature of the processing chamber 201 are regulated, raw material gas is supplied to the wafer 200 in the processing chamber 201.

[0055] Specifically, valve 243a is opened, allowing raw material gas to flow into gas supply pipe 232a. The flow rate of the raw material gas is regulated by MFC 241a, supplied to processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, raw material gas is supplied to wafer 200. Additionally, valves 243d and 243e can be opened at this time, supplying N2 gas to processing chamber 201 via nozzles 249a and 249b respectively.

[0056] As a processing condition in this step, an example can be provided.

[0057] Feed gas supply flow rate: 0.1~5slm

[0058] Raw material gas supply time: 1–180 minutes

[0059] N2 gas supply flow rate (per gas supply pipe): 0-5 slm

[0060] Processing chamber 201 temperature (film formation temperature): 400~650℃

[0061] Pressure in processing chamber 201 (film formation pressure): 1~1330Pa.

[0062] The numerical range stated as "400~650℃" in this specification refers to the lower and upper limits being included within this range. Therefore, for example, "400~650℃" means "above 400℃ and below 650℃". The same applies to other numerical ranges.

[0063] By supplying a raw material gas to the wafer 200 under the above-described processing conditions, a specified film can be deposited on the surface of the wafer 200.

[0064] As feedstock gases, monosilane (SiH4, abbreviated as MS), disilane (Si2H6), trisilane (Si3H8), and tetrasilane (Si4H6) can be used. 10 ) gas, pentasilane (Si5H) 12 ) gas, hexasilane (Si6H 14 ) gas, such as silicon hydride gas.

[0065] As inert gases, N2 gas, as well as rare gases such as Ar, He, Ne, and Xe gas, can be used. This point also applies to the cleaning process described later.

[0066] (Post-purge and atmospheric pressure recovery)

[0067] After the specified film formation on wafer 200 is completed, valve 243a is closed to stop the supply of raw material gas to processing chamber 201. Then, processing chamber 201 is evacuated to remove any remaining gases. At this time, valves 243d and 243e are opened, and N2 gas, used as purging gas, is supplied to processing chamber 201 through nozzles 249a and 249b, and exhausted from exhaust port 231a. Thus, processing chamber 201 is purged, and any remaining gases and reaction byproducts are removed (post-purging). Then, the atmosphere in processing chamber 201 is replaced with an inactive gas (inactive gas replacement), and the pressure in processing chamber 201 is restored to atmospheric pressure (atmospheric pressure restoration).

[0068] (Crystal boat unloading, wafer removal)

[0069] Then, the sealing cover 219 is lowered using the crystal boat lift 115, opening the lower end of the manifold 209. The processed wafer 200, supported by the crystal boat 217, is then moved from the lower end of the manifold 209 to the outside of the reaction tube 203 (crystal boat unloading). After unloading, the gate 219s moves, sealing the lower opening of the manifold 209 by means of an O-ring 220c (gate closing). The processed wafer 200 is then removed from the crystal boat 217 after being moved to the outside of the reaction tube 203 (wafer removal).

[0070] (3) Cleaning treatment

[0071] During the film-forming process described above, deposits containing the thin film accumulate inside the processing container, such as on the inner wall of the reaction tube 203, the surfaces of nozzles 249a and 249b, and the surface of the crystal boat 217. That is, the deposits containing the thin film adhere to the surfaces of components within the processing chamber 201, which are heated to the film-forming temperature. In this method, when the amount of deposits accumulated in the processing container, i.e., the accumulated film thickness, reaches a predetermined amount (thickness) before the deposits peel off and fall off, a cleaning process to remove the deposits is performed.

[0072] In this cleaning process, a cleaning gas is supplied into the processing container to remove deposits adhering to components and other parts inside the container. It should be noted that the process of removing these deposits may also be included in one step of the semiconductor device manufacturing process described above. In the following description, the operation of each part constituting the substrate processing apparatus is also controlled by the controller 121.

[0073] (Empty Crystal Boat Loading)

[0074] The gate 219s is moved by the gate opening and closing mechanism 115s, opening the lower end of the manifold 209 (gate open). Then, the empty manifold 217, i.e., the manifold 217 without wafers 200, is lifted by the crystal boat elevator 115 and moved into the processing chamber 201. In this state, the sealing cover 219 seals the lower end of the manifold 209 by means of the O-ring 220b.

[0075] (Pressure and temperature regulation)

[0076] After the crystal boat 217 is moved into the processing chamber 201, vacuum exhaust (pressure regulation) is performed using the vacuum pump 246 to bring the processing chamber 201 to the desired pressure. Additionally, the processing chamber 201 is heated using the heater 207 (temperature regulation) to bring it to the desired temperature (first temperature). At this time, the components inside the processing chamber 201, namely the inner wall of the reaction tube 203, the surfaces of the nozzles 249a and 249b, and the surface of the crystal boat 217, are also heated to the first temperature. Furthermore, the rotation of the crystal boat 217, performed using the rotation mechanism 267, is initiated. The operation of the vacuum pump 246, the heating of the processing chamber 201, and the rotation of the crystal boat 217 continue at least until the cleaning process described later is completed. It should be noted that the crystal boat 217 may not be rotated.

[0077] (clean)

[0078] After the pressure and temperature of the processing chamber 201 are regulated, clean gas is supplied to the heated processing chamber 201, which does not contain the wafer 200. Specifically, valve 243b is opened, allowing clean gas to flow into the gas supply pipe 232b. The clean gas flow rate is regulated by MFC 241b, and it is supplied to the processing chamber 201 via the gas supply pipe 232b and nozzle 249b, and exhausted from the exhaust port 231a. At this time, valves 243d and 243e can be opened simultaneously, supplying N2 gas to the processing chamber 201 via nozzles 249a and 249b.

[0079] As a processing condition in this step, an example can be given:

[0080] Clean gas supply flow rate: 0.1~5slm

[0081] N2 gas supply flow rate (per gas supply pipe): 0-50 slm

[0082] Gas supply time: 0.5–60 minutes, preferably 5–20 minutes

[0083] Processing temperature (chamber cleaning temperature): 100–600℃, preferably 350–450℃

[0084] Processing pressure (chamber cleaning pressure): 1–30000 Pa, preferably 1000–5000 Pa.

[0085] By supplying a cleaning gas to the processing chamber 201 under the aforementioned processing conditions, active species such as free radicals can be generated within the processing chamber 201. The cleaning gas comes into contact with components within the processing chamber 201, such as the inner wall of the reaction tube 203, the surfaces of nozzles 249a and 249b, and the surface of the crystal boat 217. At this time, through a thermochemical reaction (etching reaction), deposits on the surfaces of the components within the processing chamber 201 can be removed.

[0086] (Post-purging and atmospheric pressure recovery steps)

[0087] After a specified time, the cleaning of the treatment chamber 201 is completed. Then, valve 243b is closed, stopping the supply of cleaning gas to the treatment chamber 201. Next, the treatment chamber 201 is purged using the same procedures as the post-purging process for film formation (post-purging). At this time, the purging of the treatment chamber 201 can be performed intermittently by repeatedly opening and closing valve 243b (circular purging). Then, the atmosphere in the treatment chamber 201 is replaced with N2 gas (inactive gas replacement), and the pressure in the treatment chamber 201 is restored to atmospheric pressure (atmospheric pressure restoration).

[0088] (Jingzhou Unloading)

[0089] Then, the sealing cover 219 is lowered using the crystal boat lift 115, opening the lower end of the manifold 209, and the empty crystal boat 217 is moved from the lower end of the manifold 209 to the outside of the reaction tube 203 (crystal boat unloading). After the crystal boat is unloaded, the gate 219s is moved, and the lower end opening of the manifold 209 is sealed by the gate 219s via the O-ring 220c. When this series of processes is completed, the above-mentioned film formation process is started again (see...). Figure 4 ).

[0090] (4) The start time of cleaning treatment

[0091] The following section will explain the start time of the cleaning process in this method, while comparing it with the reference example.

[0092] Figure 5 The reference example shown in Figure (b) is a common example of operation of conventional substrate processing apparatus, which shows the following situation: when the cumulative film thickness in the processing furnace reaches the specified thickness in the nth film deposition process (n is an integer greater than or equal to 1) and becomes a state that requires cleaning, the cleaning process will start automatically immediately after the nth film deposition process is completed.

[0093] like Figure 5 As shown in the reference example in Figure (b), when cleaning is performed immediately after film formation, Figure 5 A large temperature difference was observed between the (n+1)th film-forming process after the cleaning treatment shown in Figure (b) and the (n+1)th film-forming process without the cleaning treatment. In particular, the temperature difference at the beginning of the film-forming process resulted in different temperature histories during the film-forming process, which is considered to be the reason for the difference in processing quality between the film-forming processes.

[0094] When the nth film deposition process is completed but the (n+1)th film deposition process has not yet begun, the substrate processing apparatus is configured to enter an "idle state" until the (n+1)th film deposition process should begin. In the idle state, to reduce operating and maintenance costs, it is preferable to keep the heater 207 in a non-operating state (heater output power is zero) or to significantly reduce the heater output power. Therefore, the substrate processing apparatus is sometimes configured to control the heater 207 in such a manner.

[0095] Here, according to the implementation process of the film deposition process (semiconductor device manufacturing process), the idle state sometimes lasts for a relatively long time. Therefore, when starting the (n+1)th film deposition process after a long idle state, the temperature of the processing chamber sometimes drops significantly compared to the case where film deposition is performed continuously without long idle periods. It takes a longer time to raise the temperature of the processing chamber 201, which has dropped so significantly, to a temperature suitable for film deposition, compared to the case where film deposition is performed continuously without idle periods.

[0096] Therefore, the thermal history of the wafer 200 after cleaning, experiencing a long period of idle time, and then undergoing the (n+1)th substrate treatment tends to be longer than that of the wafer 200 without cleaning, i.e., continuously undergoing film formation without any interval of idle time.

[0097] In order to solve the above-mentioned new problems, Figure 5 In the method shown in Figure (a), when the accumulated film thickness reaches a specified thickness during the nth substrate treatment, i.e., when cleaning is required, the cleaning process is performed just before the (n+1)th film deposition treatment begins, rather than immediately after the nth film deposition treatment. Figure 5 In Figure (a), the temperature during the cleaning process is the same as the temperature during the film formation process, but this is an example used to illustrate stabilizing the temperature at the start of the film formation process. That is, it is not necessary to make the temperature during the cleaning process the same as the temperature during the film formation process. What is important is to keep the temperature inside the processing furnace 202 constant at the start of the film formation process.

[0098] Specifically, the substrate processing apparatus of this method is configured such that, after n film deposition processes have been performed but the situation has not yet become the case where the (n+1)th film deposition process should begin, i.e., before the execution command for the (n+1)th film deposition process has been received, the cleaning process is not started, but the process is transferred to a "new idle state" where the situation is waiting for the (n+1)th film deposition process to begin.

[0099] It can be said that the idle state in this method is similar to the following aspects: Figure 5 The idle state of the reference example shown in Figure (b) is completely different: although it is in a state where cleaning should be performed, the process is not started, that is, although there is a process that should be performed, the process is not started, and the heater 207 is not operated or its output power is reduced, waiting for the start command of the n+1th film formation process.

[0100] Furthermore, regarding the idle state in this method, when a start command for the (n+1)th film-forming process is received, the film-forming process that has already received the command does not begin; instead, the film-forming process is performed after the cleaning process has been completed. Therefore, in Figure 5 In the reference example shown in Figure (b), it is assumed that the temperature at the start of the film formation process is completely different due to the time spent in the idle state (or film formation processing room), but as... Figure 5 In the method shown in Figure (a), the temperature at the start of the film deposition process can be stabilized regardless of the idle time. Furthermore, the condition under which the film deposition process should begin is described as the moment an execution command for the film deposition process is received, but it could also be, for example, the moment when all the substrates to be processed are placed into the apparatus.

[0101] In this method, control is performed such that the period T2 from the completion of the cleaning process to the start of the (n+1)th film deposition process is shorter than the period T1 from the completion of the nth film deposition process to the start of the cleaning process. Therefore, at the start of the (n+1)th film deposition process, the heat generated during the cleaning process can be utilized efficiently. This ensures that the thermal history of the wafer 200 in the (n+1)th film deposition process is consistent with the thermal history of the wafer 200 in continuous film deposition processes. As a result, the processing conditions (e.g., temperature) at the start of the film deposition process can be stabilized regardless of the standby time between film deposition processes, thus enabling uniform processing quality of the wafer 200. It should be noted that in this case, it is not necessary for the processing conditions to be completely consistent; a certain degree of error within a specified range is acceptable, as long as it does not affect the processing of the wafer 200.

[0102] It should be noted that the configuration is preferably as follows: when transitioning to a new idle state, until the execution command for the (n+1)th film deposition process is received, the operation restricting the cleaning process is not controlled by the operator, but is autonomously and automatically controlled by the controller 121. In this case, even if a start command for the cleaning process is input to the substrate processing apparatus by the operator, the interlocking device will automatically operate to restrict the start of the cleaning process until the execution command for the (n+1)th process is received.

[0103] As mentioned earlier, in this method, even if the process changes to a state requiring cleaning during the nth substrate processing, cleaning does not automatically begin after the nth substrate processing is completed. Instead, it waits for an instruction to perform the (n+1)th substrate processing after the nth substrate processing is completed, and only begins cleaning after receiving the instruction. Then, after cleaning is completed (because the instruction for the (n+1)th substrate processing has been received), the (n+1)th substrate processing can begin immediately. In this way, by performing cleaning just before the (n+1)th substrate processing is about to begin, the temperature drop in the processing chamber at the start of the substrate processing can be suppressed.

[0104] (5) Effects of this method

[0105] According to this method, one or more of the effects shown below can be obtained.

[0106] (a) Since a cleaning process is performed before the start of the (n+1)th film deposition process, the heat generated during the cleaning process can be utilized efficiently at the start of the (n+1)th film deposition process. This ensures that the thermal history of the wafer 200 in the (n+1)th film deposition process is consistent with the thermal history of the wafer 200 in the other film deposition processes (1st to nth). As a result, the processing quality between film deposition processes can be homogenized.

[0107] (b) Since the cleaning process is performed before the (n+1)th film-forming process begins, the heat generated during the cleaning process can be utilized efficiently, regardless of the time elapsed until the start of the (n+1)th film-forming process. Therefore, the processing conditions at the start of the film-forming process can be made consistent regardless of the length of the standby time. As a result, the processing quality between film-forming processes can be homogenized.

[0108] (c) The actions of limiting the above cleaning process are controlled autonomously and automatically by the controller 121. Therefore, it is possible to prevent the cleaning process from starting at the wrong time due to the operator's operation, thereby making the processing quality of the film forming process uniform.

[0109] (d) According to this method, since the cleaning process is performed before the start of the (n+1)th film formation process, in the new idle state, by making the heater 207 not operate or reducing its output power, the power consumption can be reduced so that the processing furnace 202 can be made more durable. In addition, the processing quality between film formation processes can be made uniform.

[0110] <Another way of publishing this text>

[0111] The foregoing has provided a detailed description of the manner in which this disclosure is made. However, this disclosure is not limited to the manner described above and various changes may be made without departing from its spirit.

[0112] For example, it can also be suitably applied to the following situations: when a Si-based film such as a silicon film (Si film), a silicon oxide film (SiO film), a silicon nitride film (SiN film), or a silicon carbide film (SiC film) is formed on the wafer 200 as a specified film. Additionally, it can also be suitably applied to the situation where a titanium nitride film (TiN film) is formed on the wafer 200. Furthermore, it can also be suitably applied to the situation where a high-k dielectric insulating film such as an aluminum oxide film (AlO film) is formed on the wafer 200.

[0113] In addition, fluorine-based gases such as fluorine (F2), hydrogen fluoride (HF), and nitrogen fluoride (NF3), or mixtures thereof, can also be used as cleaning gases. Additionally, chlorine-based gases such as hydrogen chloride (HCl) can also be used appropriately.

[0114] In the above-described manner, the process used for each process is preferably prepared individually according to the processing content and stored in advance in the storage device 121c via an electrical communication line and an external storage device 123. Furthermore, it is preferable that when each process begins, the CPU 121a appropriately selects a suitable process from the multiple processes stored in the storage device 121c according to the processing content. This allows for the reproducible formation of films of various types, compositions, qualities, and thicknesses within a single substrate processing apparatus. Additionally, it reduces the operator's workload, avoids operational errors, and enables rapid initiation of each process.

[0115] Furthermore, it is preferable to establish a pre-association between the process and the cleaning process and store it in the storage device 121c, so that the cleaning gas can be appropriately selected according to the membrane type. Additionally, in this method, it is preferable to fix the execution time of the cleaning process. In short, it is preferable to keep the cleaning processing time (the supply time of the cleaning gas) constant. Therefore, by performing the cleaning process just before the process begins, the state within the processing furnace 202 at the start of the process can be stabilized.

[0116] The aforementioned process is not limited to newly manufactured cases; for example, it can also be prepared by modifying an existing process already installed in the substrate processing apparatus. In the case of a modified process, the modified process can also be installed in the substrate processing apparatus via an electrical communication line and a recording medium containing the modified process. Alternatively, the input / output device 122 of the existing substrate processing apparatus can be operated to directly modify the existing process already installed in the substrate processing apparatus.

[0117] The above method illustrates an example of determining whether a cleaning process should be performed based on whether the cumulative film thickness within the processing furnace 202 has reached a predetermined thickness; however, this disclosure is not limited to this. For example, it is also possible to determine whether a cleaning process should be performed based on whether the film-forming process has been performed a predetermined number of times. Alternatively, it is also possible to determine whether a cleaning process should be performed based on whether the operator has given instructions, rather than relying on these determinations. Furthermore, it is also possible to determine based on the number of times the component to be cleaned has been used or the usage time. Thus, the criteria (determination elements) for determining whether a cleaning process should be performed can be arbitrarily set.

[0118] In the above-described method, the substrate processing apparatus is configured to perform a film formation process. However, the film formation process can also be, for example, the formation of CVD, PVD, oxide films, nitride films, or the formation of films containing metals. Furthermore, the specific content of the substrate processing is not limited; it can include not only film formation but also annealing, oxidation, nitride, diffusion, and other processes. Additionally, it can be applied to other substrate processing apparatuses, such as exposure apparatuses, photolithography apparatuses, coating apparatuses, and plasma-based CVD apparatuses. Furthermore, while a semiconductor manufacturing apparatus is shown as an example of a substrate processing apparatus, it is not limited to semiconductor manufacturing apparatuses; it can also be an apparatus for processing glass substrates, such as an LCD apparatus.

[0119] The above method describes an example of forming a film using a batch substrate processing apparatus that processes multiple substrates at a time. This disclosure is not limited to the above method; for example, it can also be suitably applied when forming a film using a monolithic substrate processing apparatus that processes one or several substrates at a time. Furthermore, the above method describes an example of forming a film using a substrate processing apparatus with a hot-wall type furnace. This disclosure is not limited to the above method; it can also be suitably applied when forming a film using a substrate processing apparatus with a cold-wall type furnace.

[0120] When using the substrate processing apparatus described above, each process can be performed under the same processing steps and conditions as described above to obtain the same effect as described above.

[0121] Furthermore, the above methods can be used in appropriate combinations. The processing steps and conditions in this case can be the same as those in the methods described above.

[0122] Explanation of reference numerals in the attached figures

[0123] 200 wafers (substrates)

[0124] Processing Room 201.

Claims

1. A method for manufacturing a semiconductor device, comprising: (a) A process of processing a substrate by supplying a processing gas to the substrate disposed in a processing chamber; and, (b) A process of removing deposits on components adhering to the processing chamber by supplying a cleaning gas to the processing chamber when the substrate is not present in the processing chamber. The process of stabilizing the temperature of the processing chamber during the execution of (a) when it is to begin, where n is an integer greater than 1, is a step where the period T2 from the completion of execution of (b) when it is to begin in the case where (a) should start for the (n+1)th time.

2. The method for manufacturing a semiconductor device as described in claim 1, wherein, When the state becomes such that (b) should be performed, (b) should begin at the moment when the state becomes such that (a) should begin for the (n+1)th time, rather than immediately after (a) has been performed n times without being accompanied by (b).

3. The method of manufacturing a semiconductor device as claimed in claim 2, further comprising step (c), which, after performing step (a) n times without becoming a situation where step (a) should begin for the (n+1)th time, transitions to an idle state waiting for the situation where step (a) should begin for the (n+1)th time, instead of starting step (b).

4. The method for manufacturing a semiconductor device as described in claim 3, wherein, In the idle state, when it becomes the case that the (n+1)th occurrence of (a) should begin, (a) is performed after (b).

5. The method for manufacturing a semiconductor device as described in claim 1, wherein, Execute (b) just before (a) is about to begin.

6. The method for manufacturing a semiconductor device as described in claim 1, wherein, Make the period T2 from the completion of execution (b) to the start of execution (a) for the (n+1)th time zero.

7. The method for manufacturing a semiconductor device as claimed in claim 1, wherein, Keep the processing conditions in (b) constant.

8. The method for manufacturing a semiconductor device as claimed in claim 1, wherein, In the processing conditions described in (b), the temperature of the processing chamber is kept within a specified range.

9. The method for manufacturing a semiconductor device as claimed in claim 1, wherein, Make the execution time of (b) constant.

10. The method for manufacturing a semiconductor device as claimed in claim 1, wherein, The supply time of the clean gas in (b) is kept constant.

11. The method for manufacturing a semiconductor device as claimed in claim 1, wherein, The processing gas is selected from monosilane (SiH4), disilane (Si2H6), trisilane (Si3H8), and tetrasilane (Si4H6). 10 ) gas, pentasilane (Si5H) 12 ) gas and hexasilane (Si6H 14 The group of gases contains silicon hydride gas.

12. The method for manufacturing a semiconductor device as claimed in claim 1, wherein, The cleaning gas is a fluorine-based gas selected from the group consisting of fluorine (F2), hydrogen fluoride (HF), and nitrogen fluoride (NF3), or a mixture thereof.

13. The method for manufacturing a semiconductor device as claimed in claim 1, wherein, In the process of processing the substrate, a film is formed, the film being selected from the group consisting of a Si-based film comprising at least any one of a silicon film (Si film), a silicon oxide film (SiO film), a silicon nitride film (SiN film), and a silicon carbide film (SiC film), a metal film comprising a titanium nitride film (TiN film), and a high-k insulating film comprising an aluminum oxide film (AlO film).

14. A substrate processing method, comprising: (a) A process of processing a substrate by supplying a processing gas to the substrate disposed in a processing chamber; and, (b) A process of removing deposits on components adhering to the processing chamber by supplying a cleaning gas to the processing chamber when the substrate is not present in the processing chamber. The process of stabilizing the temperature of the processing chamber during the execution of (a) when it is to begin, where n is an integer greater than 1, is a step where the period T2 from the completion of execution of (b) when it is to begin in the case where (a) should start for the (n+1)th time.

15. A substrate processing apparatus, comprising: A processing chamber for housing substrates; A processing gas supply system that supplies processing gas to the processing chamber; A clean gas supply system that supplies clean gas to the processing chamber; A heating mechanism that heats the processing chamber; The control unit is configured to control the processing gas supply system, the cleaning gas supply system, and the heating mechanism to perform the following processing: (a) Processing of supplying the processing gas to a substrate disposed in the processing chamber; (b) A process in which the cleaning gas is supplied to the heated processing chamber in the absence of the substrate in the processing chamber to remove deposits adhering to the components within the processing chamber. When performing (a) and (b), the period T2 from the completion of the execution of (b) when the (n+1)th execution of (a) should begin to the start of the execution of (a) is shorter than the period T1 from the completion of the nth execution of (a) to the start of the execution of (b) when the (n+1)th execution of (a) should begin, and the temperature of the processing chamber is stabilized when the (a) is executed when the (n+1)th execution of (a) should begin, where n is an integer greater than or equal to 1.

16. A computer-readable recording medium containing a program that enables a substrate processing apparatus to perform the following steps using a computer: (a) A step of processing the substrate by supplying processing gas to the substrate disposed in the processing chamber of the substrate processing apparatus; (b) The step of supplying a cleaning gas to the processing chamber in a state where the substrate is not present in the processing chamber to remove deposits adhering to the components inside the processing chamber; and, The step of stabilizing the temperature of the processing chamber during the execution of (a) when it is to begin is to make the period T2 from the completion of the execution of (b) when it should begin in the case of the (n+1)th execution of (a) shorter than the period T1 from the completion of the execution of (a) when it is to begin in the case of the (n+1)th execution of (a), where n is an integer greater than or equal to 1.

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