Detection method, substrate processing system, and control program

Abstract

To provide a detection method and a substrate processing system for detecting an opening / closing state of a lid of a substrate accommodating container.SOLUTION: In a substrate processing system including an exhaust unit for exhausting the inside of a substrate accommodating container, the exhaust unit including a flow rate measuring unit for measuring an exhaust flow rate which is the flow rate of gas exhausted from the inside of the substrate accommodating container, a method for detecting opening / closing of a lid of the substrate accommodating container for accommodating a plurality of substrates to be processed in multiple stages includes a step of changing a first state to a second state in which the lid of the substrate accommodating container is closed, a step of releasing the abutment between a port door and the lid from the second state, and moving the substrate accommodating container in a direction away from the port door, and a step of continuously exhausting the inside of the substrate accommodating container and measuring the exhaust flow rate during the execution of the second step, thereby evaluating whether the lid of the substrate accommodating container has been closed normally.SELECTED DRAWING: Figure 11

Description

Technical Field

[0001] The present disclosure relates to a detection method, a substrate processing system, and a control program.

Background Art

[0002] Patent Document 1 discloses a wafer processing system provided with an optical sensor for detecting that a FOUP lid is in a state of being dropped off when loading and unloading a FOUP that houses a plurality of wafers from a load port.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technology according to the present disclosure detects the open / closed state of the lid of a substrate storage container.

Means for Solving the Problems

[0005] One aspect of the present disclosure is a detection method for detecting the opening and closing of a lid of a substrate storage container that stores a plurality of substrates to be processed in a substrate processing system in multiple stages. The substrate processing system includes a loader module that transfers the substrates to and from the substrate storage container. The loader module includes a load port on which the substrate storage container is placed. The load port includes a port door, and the lid of the substrate storage container is abutted against and locked to the port door. In a first state in which the lid of the substrate storage container is opened, the interior of the substrate storage container and the interior of the loader module are configured to communicate with each other. The load port includes an exhaust portion that exhausts the interior of the substrate storage container in a state where the substrate storage container is locked. The exhaust portion includes a flow rate measurement unit that measures an exhaust flow rate, which is the flow rate of gas exhausted from the interior of the substrate storage container. The detection method includes: (a) a step of changing from the first state to a second state in which the lid of the substrate storage container is closed; (b) a step of releasing the abutment between the port door and the lid and moving the substrate storage container in a direction away from the port door from the second state; and (c) a step of continuously exhausting the interior of the substrate storage container and measuring the exhaust flow rate during the execution of steps (a) and (b) to evaluate whether the lid of the substrate storage container is normally closed.

Effect of the Invention

[0006] According to the present disclosure, the opening and closing state of the lid of the substrate storage container can be detected.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0008] In the manufacturing process of semiconductor devices, it is required to maintain the cleanliness of semiconductor wafers (hereinafter referred to as "wafers") and various wafer processing apparatuses for processing wafers. For this purpose, when transporting wafers from the outside to the wafer processing apparatus, a technique is adopted to maintain a high cleanliness inside a so-called front-opening unified pod (FOUP), which is a substrate storage container that houses a plurality of wafers.

[0009] The above-described substrate storage container can accommodate a plurality of wafers in multiple stages in a parallel state, and is configured to be able to transfer wafers through an opening formed on one surface of the substrate storage container. Inside this substrate storage container, highly clean nitrogen gas or the like is enclosed to prevent the intrusion of contaminants such as particles into the substrate storage container.

[0010] Such a substrate storage container has an openable and closable lid for inserting and removing wafers. When the substrate storage container abuts (docks) against the load port, the lid is opened, and in this state, the loader module and the wafer are transferred. Further, when the substrate storage container is detached (undocked) from the load port, the lid is closed in advance.

[0011] When the substrate storage container is undocked, the lid may not be closed sufficiently due to distortion of the substrate storage container or looseness of the latch key for latching the lid to the main body of the substrate storage container in a locked state. Patent Document 1 discloses providing an optical sensor for detecting that the lid has fallen off when the substrate storage container is undocked and then unloaded.

[0012] However, the configuration of providing a sensor at the load port increases the device cost. Also, in a state where the lid is closed incompletely but still closed, since the lid does not fall, it is difficult to detect with an optical sensor. Therefore, there is room for improvement in conventional wafer transfer devices.

[0013] From such a perspective, the inventors of the present invention intensively studied and came up with a method of a reference example in which, prior to undocking the substrate storage container, after latching the lid of the substrate storage container, the opening / closing mechanism (port door) on the load port side is retracted to detect opening / closing. In the method of such a reference example, when the port door is retracted in a state where the latch of the lid is not performed normally and the lid is incompletely closed, the latch key catches on the lid and the lid falls, so that the incomplete closing of the lid can be detected. When using another hoop that does not have a configuration capable of supplying N2 gas in the hoop 31 of the embodiment described later, the detection method according to the embodiment described later cannot be implemented. Therefore, from the viewpoint of being able to detect incomplete closing of the lid, in the opening / closing detection of the other hoop, although there are problems regarding cleanliness maintenance when the lid falls into the loader module, it is effective to use the method of the reference example.

[0014] In view of the above problems and the methods of the reference examples, the technology according to the present disclosure detects the open / closed state of the lid of the substrate storage container. The open / closed state of the lid includes not only the detachment of the lid but also an incomplete closed state of the lid.

[0015] Hereinafter, a wafer processing system as a substrate processing system according to the present embodiment and a method for detecting the opening and closing of a lid will be described with reference to the drawings. In the present specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

[0016] <Configuration of Wafer Processing System> First, the configuration of a wafer processing system as a substrate processing system according to the present embodiment will be described. FIG. 1 is a plan view showing an outline of the configuration of the wafer processing system 1. In the wafer processing system 1, desired processes such as a film forming process and an etching process are performed on a wafer W as a substrate in a reduced pressure atmosphere (vacuum atmosphere). Note that the configuration of the wafer processing system 1 of the present disclosure is not limited to this and can be arbitrarily selected.

[0017] As shown in FIG. 1, the wafer processing system 1 has a configuration in which an atmospheric pressure section 10 and a reduced pressure section 11 are integrally connected via load lock modules 20a and 20b. In the atmospheric pressure section 10, a FOUP 31 (described later), which is a substrate storage container capable of accommodating a plurality of wafers W in an atmospheric pressure atmosphere (atmospheric atmosphere), is conveyed, and the wafer W is further conveyed to the load lock modules 20a and 20b. In the reduced pressure section 11, a desired process is performed on the wafer W in a reduced pressure atmosphere (vacuum atmosphere), and the wafer W is further conveyed to the load lock modules 20a and 20b.

[0018] Inside the load lock module 20a, a stage 21a for placing the wafer W is provided. The load lock module 20a temporarily holds the wafer W on the stage 21a in order to deliver the wafer W conveyed from a loader module 30 (described later) in the atmospheric pressure section 10 to a transfer module 40 (described later) in the reduced pressure section 11.

[0019] The load lock module 20a is connected to a loader module 30, which will be described later, via a gate valve 22a. The load lock module 20a is also connected to a transfer module 40, which will be described later, via a gate valve 23a. The gate valves 22a and 23a ensure airtightness between the load lock module 20a and the loader module 30 and the transfer module 40, and enable communication between them.

[0020] An air supply unit (not shown) for supplying gas and an exhaust unit (not shown) for discharging gas are connected to the load lock module 20a, and the interior thereof is configured to be switchable between a normal pressure atmosphere and a reduced pressure atmosphere by the air supply unit and the exhaust unit. That is, the load lock module 20a is configured to be able to appropriately transfer the wafer W between the normal pressure section 10 of the normal pressure atmosphere and the reduced pressure section 11 of the reduced pressure atmosphere.

[0021] The load lock module 20b has the same configuration as the load lock module 20a. That is, the load lock module 20b includes a stage 21b on which the wafer W is placed, a gate valve 22b on the loader module 30 side, and a gate valve 23b on the transfer module 40 side.

[0022] Note that the number and arrangement of the load lock modules 20a and 20b are not limited to those in this embodiment and can be arbitrarily set.

[0023] The normal pressure section 10 includes a loader module 30 provided with a wafer transfer device 33 and a load port 32 on which a hoop 31 capable of storing a plurality of wafers W is placed. Note that the loader module 30 is also referred to as an EFEM (Equipment Front End Module).

[0024] The loader module 30 is composed of a housing with a substantially rectangular shape inside, and the inside of the housing is maintained at a pressure higher than the peripheral atmosphere outside the wafer processing system 1. On one side surface constituting the long side of the housing of the loader module 30, a plurality of, for example, three load ports 32 are arranged side by side. In FIG. 1, hoops 31 are placed on the left load port 32 and the central load port 32 on the drawing surface, and the state where the hoop 31 is not placed on the right load port 32 is shown. On the other side surface constituting the long side of the housing of the loader module 30, load lock modules 20a and 20b are arranged side by side. Further, the loader module 30 has a wafer transfer device 33 that can move in the longitudinal direction inside the housing. The wafer transfer device 33 can transfer the wafer W between the hoop 31 placed on the load port 32 and the load lock modules 20a and 20b. The details of the configurations of the hoop 31 and the load port 32 will be described later.

[0025] The decompression unit 11 has a transfer module 40 that transports the wafer W and a processing module 41 as a substrate processing device that performs a desired process on the wafer W. The inside of the transfer module 40 and the inside of the processing module 41 are each maintained in a decompressed atmosphere. A plurality of, for example, four processing modules 41 are provided for the transfer module 40. The transfer module 40 is also referred to as a VTM (Vacuum Transfer Module).

[0026] The transfer module 40 has a housing that is polygonal in plan view, hexagonal in the illustrated example, and is connected to the load lock modules 20a and 20b via the gate valves 23a and 23b as described above. That is, on each side surface of the transfer module 40, the load lock modules 20a and 20b and the four processing modules 41 are arranged. Then, the transfer module 40 sequentially transfers the wafer W transported to the load lock module 20a to one processing module 41 to perform a desired process, and then unloads it to the normal pressure unit 10 via the load lock module 20b.

[0027] Inside the transfer module 40, a wafer transfer device 50 for transferring the wafer W between the load lock modules 20a and 20b, the transfer module 40, and the processing module 41 is provided.

[0028] Inside the processing module 41, a stage 42 for placing the wafer W is provided. The processing module 41 performs a desired process such as a film forming process or an etching process on the wafer W placed on the stage 42. Note that an air supply unit (not shown) for supplying a processing gas, a purge gas, etc. and an exhaust unit (not shown) for discharging the gas are connected to the processing module 41.

[0029] Further, the processing module 41 is connected to the transfer module 40 via a gate valve 43. This gate valve 43 achieves both ensuring airtightness and mutual communication between the transfer module 40 and the processing module 41.

[0030] Note that the number, arrangement, and type of processes of the processing module 41 provided in the transfer module 40 are not limited to this embodiment and can be arbitrarily set.

[0031] The above wafer processing system 1 is provided with a control unit 60. The control unit 60 processes computer-executable instructions for causing the wafer processing system 1 to execute various processes described in the present disclosure. The control unit 60 can be configured to control each element of the wafer processing system 1 so as to execute the various processes described herein. In one embodiment, part or all of the control unit 60 may be included in the wafer processing system 1. The control unit 60 may include a processing unit, a storage unit, and a communication interface. The control unit 60 is realized by, for example, a computer. The processing unit can be configured to read a program from the storage unit and perform various control operations by executing the read program. This program may be stored in the storage unit in advance, or may be acquired via a medium when necessary. The acquired program is stored in the storage unit and read from the storage unit by the processing unit and executed. The medium may be various storage media readable by a computer, or may be a communication line connected to the communication interface. The processing unit may be a CPU (Central Processing Unit). The storage unit may be temporary or non-temporary, and may include a RAM (Random Access Memory), a ROM (Read Only Memory), an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination thereof. The communication interface may communicate with the wafer processing system 1 via a communication line such as a LAN (Local Area Network).

[0032] <Hoop and Load Port>

[0033] FIG. 2 is a perspective view showing a configuration example of the hoop 31 and the load port 32. FIG. 3 is a cross-sectional view taken in a direction perpendicular to the longitudinal direction of the loader module, and shows an example of a state where the hoop 31 abuts (docks) against the wafer transfer port 70 at the load position. FIG. 4 is a plan view showing a configuration example of the bottom of the hoop 31. FIG. 5 is a plan view showing a configuration example of the base 71 and the stage 72 in the load port 32.

[0034] As shown in FIG. 2, each load port 32 includes a wafer transfer port 70, a base 71, a stage (mounting table) 72 on which a hoop 31 provided thereon is placed, and a port door 73 that closes the wafer transfer port 70. The stage 72 is adapted to move forward and backward along a rail 74 extending in the front-rear direction by a stage moving mechanism (not shown). By the forward and backward movement of the stage 72, the hoop 31 moves between an unload position which is the backward position and a load position which is the forward position. A state where the hoop 31 is placed at the unload position is shown. The hoop 31 is transported onto the stage 72 at the unload position while being gripped by a gripping portion (not shown) by an appropriate transport device. Then, the stage 72 moves forward, and at the load position, the hoop 31 is connected to the loader module 30, enabling the transfer of the wafer W by the wafer transfer device 33. The wall surface of the loader module 30 excluding the wafer transfer port 70 is referred to as a partition wall 75. The port door 73 includes a latch key 76 that latches the hoop 31 and a lid 80 as will be described later.

[0035] As shown in FIG. 3, the hoop 31 has a box-like shape with an open front and includes a lid 80 that seals the opening. In the following description, when the hoop 31 is docked to the wafer transfer port 70, the lid 80 is docked to the port door 73. The bottom 31a of the hoop 31 is configured to be supported by the stage 72.

[0036] The stage 72 is provided with a desired locking member (not shown), and by this locking member, the stage 72 and the hoop 31 can be locked (clamped) at a desired position. The hoop 31 is provided with a support mechanism corresponding to the mechanism of the locking member. That is, when the hoop 31 is "clamped" to the stage 72, it means that the control of the locking by the action of the mechanism of the locking member of the stage 72 on the support mechanism of the hoop 31 is completed. Also, "unclamped" means, conversely, that the control of the release of the locking by the action of the mechanism of the locking member of the stage 72 on the support mechanism of the hoop 31 is completed. The stage 72 may be provided with a desired positioning pin (not shown) and may be configured to guide the hoop 31 to an accurate position by the positioning pin during clamping.

[0037] The lid 80 is provided with a fitting member (not shown), and is configured to be airtightly closable in a state where the lid 80 and the hoop 31 are in close contact. The lid 80 is provided with a keyhole (not shown) at a position facing the latch key 76 in a state where the lid 80 is docked to the port door 73. The lid 80 and the hoop 31 are provided with a desired locking mechanism (not shown), and when the latch key 76 is fitted into the keyhole, the fitting member moves by the operation of the latch key 76, so that the lid 80 is configured to be in a locked state (latched) with respect to the hoop 31. That is, when the lid 80 is "latched" with respect to the hoop 31, it means that the control of a series of operations for moving the fitting member and making the lid 80 in a locked state with respect to the hoop 31 is completed. Also, "unlatched" means, conversely, that the control of a series of operations for moving the fitting member and releasing the locked state of the lid 80 with respect to the hoop 31 is completed. Further, the port door 73 is configured to be openable and closable by a drive mechanism (not shown). Therefore, by docking the port door 73 and the lid 80 and operating the port door 73 to open and close in a state where the latch key 76 is fitted into the keyhole, the lid 80 can be opened and closed.

[0038] Inside the hoop 31, for example, 25 wafers W to be processed by a wafer processing apparatus are accommodated. Each wafer W is arranged horizontally and at equal intervals in multiple stages inside the hoop 31.

[0039] As shown in Fig. 4, three gas supply ports 90 and one gas exhaust port 91 are provided at the bottom 31a of the hoop 31. In the present embodiment, two of the gas supply ports 90 are arranged on the side opposite to the lid 80, and one is arranged on the lid 80 side. The gas exhaust port 91 is arranged on the lid 80 side.

[0040] As shown in Fig. 5, through holes 100 are provided in the stage 72 at positions corresponding to the gas supply port 90 and the gas exhaust port 91 provided in the hoop 31. Gas supply connectors 101 are provided on the base 71 at positions corresponding to the gas supply ports 90 of the hoop 31. Flexible gas supply pipes 102 are connected to the gas supply connectors 101. The other end side of the gas supply pipe 102 is connected to a gas supply source (not shown), and is configured to supply dried purge gas, for example, N2 gas through the gas supply pipe 102. Further, an exhaust connector 104 is provided on the base 71 at a position corresponding to the gas exhaust port 91 of the hoop 31. A flexible exhaust pipe 105 is connected to the exhaust connector 104.

[0041] The gas supply connector 101 and the exhaust connector 104 are configured to be able to move up and down by a lifting mechanism (not shown) such as an air cylinder. Ring-shaped seal members (not shown) are provided at the tips of the gas supply connector 101 and the exhaust connector 104. With such a configuration, by raising the gas supply connector 101, the gas supply connector 101 can communicate with the gas supply port 90 of the hoop 31 to supply purge gas into the hoop 31. Also, by raising the exhaust connector 104, the exhaust connector 104 can communicate with the gas exhaust port 91 of the hoop 31 to exhaust the inside of the hoop 31.

[0042] 6 is an explanatory diagram showing an example of the configuration of a gas system configured to supply purge gas to the FOUP 31 according to this embodiment and exhaust gas from the FOUP 31. A gas supply source 110 that supplies, for example, dry nitrogen as a purge gas is connected to the gas supply port 90 via a gas supply pipe 102. The gas supply pipe 102 is provided with a valve V1 that controls the supply and stop of gas from the gas supply source 110. The gas supply pipe 102 branches into two on the downstream side of the valve V1. Each of the branched gas supply pipes 102 is provided with a shutoff valve V2, V3. Each of the branched gas supply pipes 102 is provided with a flow rate controller 111 that is controlled to supply purge gas to each gas supply port 90 at a desired flow rate.

[0043] An exhaust mechanism 112 is connected to the gas exhaust port 91 via an exhaust pipe 105, and can exhaust the gas supplied from each gas supply port 90. A flow meter 120 is provided as a flow rate measuring unit, and is capable of measuring the flow rate of exhaust gas flowing through the exhaust pipe 105. The flow rate measured by the flow meter 120 is transmitted to the control unit 60, for example.

[0044] Returning to FIG. 3, the two gas supply ports 90 provided on the opposite side to the lid 80 are provided with distribution pipes 121 extending vertically upward inside the FOUP 31. The distribution pipes 121 have, for example, slit-shaped openings (not shown) formed on the surface facing the wafers W at a height corresponding to the gaps between the wafers W, and can distribute the gas supplied from the gas supply ports 90 evenly between the wafers W. This makes it possible to form a gas flow inside the FOUP 31 that flows from inside the FOUP 31 toward the lid 80 and flows evenly between the wafers W. As a result, even when the lid 80 is open, this gas flow can prevent the air inside the loader module 30 from flowing into the inside of the FOUP 31.

[0045] Note that matters such as the arrangement of the gas supply port 90 and the gas exhaust port 91, and the necessity of installing the distribution pipe 121 are not limited to this embodiment. For example, it is possible to arbitrarily set, such as providing two gas supply ports 90 and two gas exhaust ports 91 respectively.

[0046] Also, the number and arrangement of the load ports 32 are not limited to this embodiment and can be arbitrarily set. Further, in the normal pressure section 10, a processing module that performs a desired process on the wafer W in a normal pressure atmosphere, for example, a module that performs an alignment process for adjusting the horizontal orientation of the wafer W, may be provided.

[0047] FIG. 7 and FIG. 8 are cross-sectional views schematically showing an example of the state when the lid of the hoop 31 having the above configuration is opened and closed. When the lid 80 of the hoop 31 is opened, as shown in FIG. 7, first, the latch of the lid 80 with respect to the hoop 31 is released (unlatched), and then, by a moving mechanism (not shown), the composite body in which the port door 73 and the lid 80 are docked moves horizontally. Thereafter, as shown in FIG. 8, the composite body in which the port door 73 and the lid 80 are docked moves downward along the partition wall 75. Thereby, the wafer transfer device 33 of the loader module 30 becomes accessible to the wafer W inside the hoop 31. When the lid 80 of the hoop 31 is closed, the composite body in which the port door 73 and the lid 80 are docked moves in the reverse direction to that at the time of the above release.

[0048] FIG. 9 is a cross-sectional view schematically showing an example of a state when the hoop 31 is loaded or unloaded with respect to the load port 32. When the hoop 31 is unloaded, from the state where the hoop 31 is docked to the load port 32 and the lid 80 is opened as shown in FIG. 3, first, the lid 80 is closed and latched. Thereafter, the hoop 31 is undocked from the wafer transfer port 70, and the stage 72 moves in a direction away from the port door 73, whereby the hoop 31 is moved to the unloading position which is the retracted position. When the hoop 31 is loaded, it is moved in the reverse direction. Further, as shown in FIG. 9, the gas supply pipe 102 and the exhaust pipe 105 which are flexibly configured are moved following the movement of the hoop 31 while maintaining the state of being connected to the gas supply connector 101 and the exhaust connector 104 respectively.

[0049] <Method for Detecting Opening and Closing of Lid of Substrate Containing Container> Next, a method for detecting opening and closing of the lid 80 of the hoop 31 according to the present embodiment will be described. FIG. 10 is a timing chart showing a configuration example of the detection method according to the present embodiment and a schematic graph of the exhaust flow rate measured during each process. In the timing chart, the horizontal axis represents time, and the vertical axis represents the state of each device. Also, in the graph of the exhaust flow rate, the horizontal axis represents time, and the vertical axis represents the exhaust flow rate.

[0050] In the detection method according to the present embodiment, the opening and closing state of the lid 80 is detected during a continuous period from the state where the hoop 31 is loaded into the load port 32 and the lid 80 is opened to the state where the lid 80 is closed and the hoop 31 is unloaded from the load port.

[0051] In the initial state ST0 before the start of process ST1, the hoop 31 is loaded onto the load port 32 and the lid 80 is open, and the interior of the hoop 31 communicates with the interior of the loader module 30. The state of the hoop 31 is referred to as the first state. For example, the states in FIGS. 7 or 8 are the first state. In the first state, the gas supply connector 101 communicates with the gas supply pipe 102, and the exhaust connector 104 communicates with the exhaust pipe 105. Further, purge gas is supplied into the hoop 31 at a desired supply flow rate via the gas supply connector 101 and the gas supply port 90, and the gas in the hoop 31 is discharged via the gas exhaust port 91 and the exhaust connector 104. Further, the flow meter 120 provided in the exhaust pipe 105 measures the flow rate of the exhaust gas flowing through the exhaust pipe 105 (hereinafter referred to as the "exhaust flow rate"). The exhaust flow rate measured in the initial state ST0 is the first flow rate Q1.

[0052] In process ST1, as shown in FIG. 7, the composite body in which the port door 73 and the lid 80 are docked is moved to close the hoop 31. Thereafter, the above-described locking mechanism by the latch key 76 is actuated to latch the lid 80 and the hoop 31. Also, the exhaust flow rate is continuously measured from before the execution of process ST1. After being closed by the lid 80, the state of the latched hoop 31 is referred to as the second state. In process ST1, the exhaust flow rate measured in the hoop 31 after it becomes the second state is the second flow rate Q2. The second flow rate Q2 gradually decreases with the first flow rate Q1 as the initial value in the state example of FIG. 10 where the closing and latching of the lid 80 are properly performed, and then asymptotically approaches the third flow rate Q3 which is a stable value. Note that although the second flow rate Q2 is shown as a linear graph with a constant slope in FIG. 10, it is not limited thereto, and includes cases where it becomes a non-linear graph due to a non-uniform decrease. Also, when it asymptotically approaches a value sufficiently close to the third flow rate Q3, it is defined that "the exhaust flow rate has reached the third flow rate Q3". The significance of the first to third flow rates Q1 to Q3 will be described later.

[0053] In step ST2, the lid 80 is undocked from the port door 73, and the hoop 31 is moved to the unload position in a direction away from the wafer transfer port 70. Also, the exhaust flow rate is continuously measured from step ST1. The exhaust flow rate measured in step ST3 is the third flow rate Q3.

[0054] In step ST3, the measurement of the exhaust flow rate is terminated, and the communication between the gas supply connector 101 and the gas supply pipe 102 and the communication between the exhaust connector 104 and the exhaust pipe 105 are disconnected. Thereafter, the locking between the hoop 31 and the stage 72 is released (unclamped).

[0055] Thereafter, the hoop 31 may be removed from the stage 72 and transported to another processing apparatus that performs other processing steps on the wafer W.

[0056] Here, the significance of the first to third flow rates Q1 to Q3, which are the exhaust flow rates measured during the execution from the initial state ST0 to step ST2, will be described. In the initial state ST0, the inside of the hoop 31 communicates with the inside of the loader module 30. As described above, the inside of the loader module 30 is maintained at a pressure higher than the ambient atmosphere outside the wafer processing system 1. Therefore, based on such a pressure gradient, gas flows from the loader module 30 into the hoop 31, and the flow rate of the gas exhausted from the hoop 31 becomes the relatively large first flow rate Q1.

[0057] In step ST1, the communication between the loader module 30 and the hoop 31 is blocked by closing the lid 80. Therefore, the inflow of gas from the loader module 30 into the hoop 31 stops, and the gas remaining inside the hoop 31 immediately after the lid 80 is closed is sequentially exhausted. For this reason, the remaining amount of gas inside the hoop 31 decreases, and accordingly, the second flow rate Q2 as the exhaust flow rate decreases. Thereafter, as the gas pressure inside the hoop 31 approaches equilibrium with the suction pressure for exhaust in the exhaust mechanism 112, the exhaust flow rate reaches the third flow rate Q3, which is a stable value.

[0058] In the state example shown in FIG. 10, during the execution of steps ST1 to ST3, after the exhaust flow rate once falls below a certain flow rate threshold Qt, it does not exceed the threshold Qt again until the end of step ST3. In such a case, it is evaluated that the hoop 31 is normally closed by the lid 80.

[0059] On the other hand, in other state examples, during the execution of steps ST1 to ST3, after the exhaust flow rate once falls below a certain flow rate threshold Qt, it may exceed the threshold Qt again. FIG. 11 is a schematic graph of the exhaust flow rate measured during each step in such a state example. In FIG. 11, the horizontal axis represents time and the vertical axis represents the exhaust flow rate.

[0060] In the state example shown in FIG. 11, after the exhaust flow rate reaches the third flow rate Q3 in step ST1, in step ST2, the exhaust flow rate increases and exceeds the threshold Qt. The reason for such a flow rate change is considered as follows. First, in this state example, after the hoop 31 is closed by the lid 80 in step ST1, due to the play of the latch key or the like, the latch between the lid 80 and the hoop 31 is not properly performed. In this state, then, when the lid 80 is undocked from the port door 73 in step ST2 and the hoop 31 moves for a while, the latch key 76 catches on a keyhole or the like in the lid 80, causing the lid 80 to come off and the hoop 31 to be released from the closed state. When the hoop 31 is opened in the undocked state, the inside of the hoop 31 communicates with the surrounding atmosphere outside the wafer processing system 1. The surrounding atmosphere is lower than the pressure inside the loader module 30, but higher than the pressure inside the hoop 31 when the exhaust flow rate from the hoop 31 is the third flow rate Q3. Further, the surrounding atmosphere is higher than the pressure inside the hoop 31 when the exhaust flow rate from the hoop 31 is the threshold Qt. Therefore, when the inside of the hoop 31 communicates with the surrounding atmosphere, the exhaust flow rate turns to increase, and as a result, it becomes higher than the threshold Qt.

[0061] For the reasons described above, when the exhaust flow rate once falls below a certain flow rate threshold Qt and then rises above the threshold Qt again, it is evaluated that the lid 80 has not been closed properly. When it is evaluated that the lid 80 has not been closed properly, the control unit 60 issues an alarm, for example.

[0062] In one embodiment, the detection of the closing of the lid 80 is performed without providing a threshold Qt for the exhaust flow rate. In this case, as an example, when it is detected that the exhaust flow rate has changed from decreasing to increasing after the lid 80 has been undocked from the port door 73 in step ST2, it is evaluated that the lid 80 has not been closed properly.

[0063] Also, from a certain perspective, during the execution of steps ST1 to ST3, when it is measured that the exhaust flow rate has increased by a threshold value of a predetermined increase amount, it is evaluated that the lid 80 has not been closed properly.

[0064] Note that the threshold Qt or the threshold value of the increase amount of the exhaust flow rate can be determined in advance by experiments or simulations based on the pressure inside the loader module 30, the pressure of the surrounding atmosphere, the suction pressure for exhaust in the exhaust mechanism 112, or the volume inside the hoop 31. Also, the value determined in this way may be stored in the control unit 60 and read when each step is executed.

[0065] Also, in the present embodiment, the exhaust flow rate is monitored by providing the flow meter 120 in the exhaust pipe 105, but the present invention is not limited to such an example. For example, the flow meter 120 may be provided anywhere on the exhaust line, and may be provided in the exhaust mechanism 112, for example. Also, when the flow meter 120 has the function of measuring pressure, it may be possible to monitor such pressure.

[0066] According to the method for detecting the opening and closing of the lid 80 of the hoop 31 according to the present embodiment described above, the opening and closing of the lid 80 can be detected by a simple configuration in which the flow meter 120 is provided in the exhaust pipe 105 without separately providing a sensor for detecting the opening and closing such as an optical sensor.

[0067] Also, different from the method of retracting the port door 73 after latching the lid 80 as described above, after the port door 73 is fitted to the partition wall 75 and the lid 80 is unlatched, in order to detect the opening and closing of the lid 80, even if the lid 80 falls off during the process, there is no risk of the lid 80 falling inside the loader module 30. Therefore, when recovering the fallen lid 80, it is not necessary to open the loader module 30 to the surrounding atmosphere, and the cleanliness of the loader module 30 is not impaired. Also, since it is not necessary to open the loader module 30 to the surrounding atmosphere, the lid 80 and the hoop 31 that have been detected as abnormal from the surrounding atmosphere can be quickly recovered, and a decrease in the productivity of the entire wafer processing system 1 can be suppressed.

[0068] Also, since no additional process is required to retract the port door 73 after latching the lid 80, the time required for the process from undocking to unclamping can be shortened.

[0069] Also, since the opening and closing of the lid 80 can be detected at a desired point in time from the closing of the hoop 31 by the lid 80 to unclamping, the opening and closing can be detected even at a position outside the detection range of a sensor far from the load position.

[0070] The embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The above embodiments may be omitted, substituted, or changed in various forms without departing from the scope and gist of the appended claims. For example, the constituent elements of the above embodiments can be arbitrarily combined. From such an arbitrary combination, the actions and effects of each constituent element related to the combination can be naturally obtained, and other actions and other effects obvious to those skilled in the art from the description of this specification can be obtained.

[0071] Also, the effects described in this specification are merely illustrative or exemplary and not limiting. That is, the technology according to the present disclosure can exhibit other effects obvious to those skilled in the art from the description of this specification, together with or instead of the above effects.

Description of Symbols

[0072] 1 Wafer processing system 30 Loader module 31 Hoop 32 Load port 73 Port door 80 Lid 112 Exhaust mechanism 120 Flow meter W Wafer

Claims

1. A detection method for detecting the opening and closing of a lid of a substrate storage container that stores a plurality of substrates to be processed in a substrate processing system in multiple stages, comprising: The substrate processing system includes a loader module that transfers the substrates to and from the substrate storage container. The loader module includes a load port on which the substrate storage container is placed. The load port includes a port door, and the lid of the substrate storage container abuts against and is locked to the port door. In a first state where the lid of the substrate storage container is opened, the interior of the substrate storage container and the interior of the loader module are configured to communicate with each other. The load port includes an exhaust portion that exhausts the interior of the substrate storage container when the substrate storage container is locked. The exhaust portion includes a flow rate measurement portion that measures an exhaust flow rate, which is the flow rate of gas exhausted from the interior of the substrate storage container. The detection method includes: (a) a step of changing from the first state to a second state in which the lid of the substrate storage container is closed; (b) a step of releasing the abutment between the port door and the lid and moving the substrate storage container in a direction away from the port door from the second state; (c) a step of continuously exhausting the interior of the substrate storage container and measuring the exhaust flow rate during the execution of steps (a) and (b) to evaluate whether the lid of the substrate storage container is closed normally; A detection method including the above steps.

2. (d) further including a step of comparing the exhaust flow rate with a predetermined threshold value, and if the exhaust flow rate drops below the threshold value once and then exceeds the threshold value again, evaluating that the lid of the substrate storage container is not closed normally. The detection method according to Claim 1.

3. (d) further including a step of comparing the increase amount of the exhaust flow rate with a predetermined threshold value of the increase amount when the exhaust flow rate increases, and if the increase amount of the exhaust flow rate exceeds the threshold value of the increase amount, evaluating that the lid of the substrate storage container is not closed normally. The detection method according to Claim 1.

4. A substrate processing system, comprising: a substrate storage container that stores a plurality of substrates in multiple stages; a loader module that transfers the substrates to and from the substrate storage container; a control unit, and the substrate storage container includes a lid that hermetically closes the interior of the substrate storage container. The loader module includes a load port on which the substrate storage container is placed. The load port includes a port door, and the lid of the substrate storage container is abutted and locked to the port door. In a first state where the lid of the substrate storage container is opened, the inside of the substrate storage container and the inside of the loader module are configured to communicate with each other. The load port includes an exhaust portion that exhausts the inside of the substrate storage container in a state where the substrate storage container is locked. The exhaust portion includes a flow rate measurement portion that measures an exhaust flow rate, which is a flow rate of gas exhausted from the inside of the substrate storage container. The control unit (a) a step of changing from the first state to a second state in which the lid of the substrate storage container is closed; (b) a step of releasing the contact between the port door and the lid and moving the substrate storage container in a direction away from the port door from the second state; (c) a step of continuously exhausting the inside of the substrate storage container and measuring the exhaust flow rate during the execution of steps (a) and (b) to evaluate whether the lid of the substrate storage container is normally closed; A substrate processing system that executes control including the above.

5. The control unit (d) further includes a step of comparing the exhaust flow rate with a predetermined threshold value, and if the exhaust flow rate exceeds the threshold value again after once falling below the threshold value, evaluating that the lid of the substrate storage container is not normally closed. The substrate processing system according to claim 4, which executes control including the above.

6. The control unit (d) when the exhaust flow rate increases, compares the increase amount of the exhaust flow rate with a threshold value of a predetermined increase amount, and if the increase amount of the exhaust flow rate exceeds the threshold value of the increase amount, evaluates that the lid of the substrate storage container is not normally closed. The substrate processing system according to claim 4, which executes control including the above.

7. A control program for causing a computer to control a substrate processing system so as to detect opening and closing of a lid of a substrate storage container that stores a plurality of substrates to be processed by the substrate processing system in multiple stages, The substrate processing system includes a loader module that transfers the substrate to and from the substrate storage container. The loader module includes a load port on which the substrate storage container is placed. The load port includes a port door, and a lid of the substrate storage container is abutted and locked to the port door. In a first state where the lid of the substrate storage container is opened, the interior of the substrate storage container and the interior of the loader module are configured to communicate with each other. The load port includes an exhaust unit that exhausts the interior of the substrate storage container in a state where the substrate storage container is locked. The exhaust unit includes a flow rate measurement unit that measures an exhaust flow rate, which is the flow rate of gas exhausted from the interior of the substrate storage container. The control program (a) a step of changing from the first state to a second state in which the lid of the substrate storage container is closed; (b) a step of releasing the abutment between the port door and the lid from the second state and moving the substrate storage container in a direction away from the port door; (c) a step of continuously exhausting the interior of the substrate storage container and measuring the exhaust flow rate during the execution of steps (a) and (b) to evaluate whether the lid of the substrate storage container has been normally closed; A control program that causes the computer to control the substrate processing system to execute control including the above steps.

8. (d) further including a step of comparing the exhaust flow rate with a predetermined threshold value, and if the exhaust flow rate exceeds the threshold value again after once falling below the threshold value, evaluating that the lid of the substrate storage container has not been normally closed, and causing the computer to control the substrate processing system to execute control including the above steps. The control program according to claim 7.

9. (d) when the exhaust flow rate increases, comparing the increase amount of the exhaust flow rate with a predetermined threshold value of the increase amount, and if the increase amount of the exhaust flow rate exceeds the threshold value of the increase amount, evaluating that the lid of the substrate storage container has not been normally closed, and causing the computer to control the substrate processing system to execute control including the above steps. The control program according to claim 7.

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