Wafer storage container cleaning apparatus and wafer storage container cleaning method

Abstract

To inspect wafer storage containers and to efficiently clean them. [Solution] The wafer storage container cleaning apparatus according to the embodiment includes a first inspection unit for inspecting the state of the gripping portion of the wafer storage container, a cleaning unit for cleaning at least the storage space for storing wafers in the wafer storage container, a second inspection unit for inspecting the state of the storage space, and a control unit for controlling a robot that transports the wafer storage container. The control unit controls the robot to transport the wafer storage container from the first inspection unit to the cleaning unit if it determines, based on the inspection results by the first inspection unit, that the wafer storage container is in a usable state, and controls the robot to transport the wafer storage container from the first inspection unit to a location different from the cleaning unit if it determines, based on the inspection results by the first inspection unit, that the wafer storage container is not in a usable state.

Description

Technical Field

[0001] Embodiments of the present invention relate to a wafer storage container cleaning device and a wafer storage container cleaning method.

Background Art

[0002] Conventionally, there is a wafer storage container cleaning device for cleaning and drying wafer storage containers such as FOUP (Front Opening Unified Pod) and FOSB (Front Opening Shipping Box) that store (accommodate) semiconductor wafers.

[0003] In the wafer storage container cleaning device, the wafer storage container is transported into the device, and the robot transports the wafer storage container to the cleaning tank while gripping it. Then, the cleaning tank performs a cleaning process on the wafer storage container. After the cleaning process, the dried wafer storage container is carried out of the wafer storage container cleaning device.

[0004] There is also an inspection device for inspecting the inside of the wafer storage container.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Here, in the wafer storage container cleaning device, there is a user's desire to inspect the wafer storage container and efficiently clean the wafer storage container.

[0007] The present invention was made to solve the above-mentioned problems, and its objective is to provide a wafer storage container cleaning apparatus and a wafer storage container cleaning method that can inspect wafer storage containers and efficiently clean wafer storage containers. [Means for solving the problem]

[0008] To solve the above-mentioned problems and achieve the objective, a wafer storage container cleaning apparatus according to one aspect of the present invention comprises: a first inspection unit for inspecting the state of the gripping portion of the wafer storage container; a cleaning unit for cleaning at least the storage space for storing wafers in the wafer storage container; a second inspection unit for inspecting the state of the storage space; a robot for transporting the wafer storage container from the first inspection unit to the cleaning unit and from the cleaning unit to the second inspection unit; and a control unit for controlling the robot. The control unit controls the robot to transport the wafer storage container from the first inspection unit to the cleaning unit if it is determined that the wafer storage container is in a usable state based on the inspection results of the first inspection unit, and controls the robot to transport the wafer storage container from the first inspection unit to a location different from the cleaning unit if it is determined that the wafer storage container is not in a usable state based on the inspection results of the first inspection unit.

[0009] Furthermore, a wafer storage container cleaning method according to one aspect of the present invention comprises the steps of: performing a first inspection to check the condition of the gripping portion of the wafer storage container; cleaning the storage space of the wafer storage container after the first inspection; and performing a second inspection to check the condition of the storage space of the wafer storage container after the cleaning of the storage space, wherein the step of cleaning the storage space is performed only for wafer storage containers that have been determined to be in a usable state based on the inspection results in the first inspection step. [Effects of the Invention]

[0010] According to one aspect of the present invention, it is possible to inspect a wafer storage container and to efficiently clean the wafer storage container. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a plan view showing an example of a schematic configuration of a wafer storage container cleaning apparatus according to an embodiment. [Figure 2] Figure 2 is a side view showing an example of a load port and a first inspection unit according to an embodiment. [Figure 3] Figure 3 shows an example of the configuration of the first inspection unit according to the embodiment. [Figure 4] Figure 4 shows an example of the configuration of the second inspection unit according to the embodiment. [Figure 5] Figure 5 shows an example of the configuration of the control unit according to the embodiment. [Figure 6] Figure 6 is a flowchart showing an example of the process performed by the wafer storage container cleaning apparatus according to this embodiment. [Modes for carrying out the invention]

[0012] Hereinafter, embodiments of the wafer storage container cleaning apparatus and wafer storage container cleaning method disclosed in this application will be described in detail with reference to the attached drawings. However, the wafer storage container cleaning apparatus and wafer storage container cleaning method disclosed in this application are not limited to the following embodiments. In the following embodiments, the case in which the wafer storage container to be cleaned is a FOUP will be described, but the wafer storage container to be cleaned is not limited to this. For example, the wafer storage container to be cleaned may be an FOSB.

[0013] (Embodiment) Figure 1 is a plan view showing an example of the schematic configuration of a wafer storage container cleaning apparatus 1 according to an embodiment. The wafer storage container cleaning apparatus 1 is installed, for example, in a factory that manufactures semiconductor wafers, and cleans wafer storage containers. As shown in Figure 1, the wafer storage container cleaning apparatus 1 includes a load port 2, a robot 3, a disassembly / connection stage 4, a cleaning tank 5, a vacuum tank 6, a first inspection unit 7, a second inspection unit 8, an unload port 9, and a control unit 10.

[0014] The robot 3, disassembly / combination stage 4, cleaning tank 5, vacuum chamber (vacuum drying tank) 6, first inspection unit 7, second inspection unit 8, and control unit 10 are located inside the casing 1a of the wafer storage container cleaning device 1. On the other hand, the load port 2 and unload port 9 are located across both the inside and outside of the casing 1a of the wafer storage container cleaning device 1.

[0015] Load port 2 loads the FOUP 20 to be cleaned, which is placed on the external part of casing 1a of load port 2, into the interior of casing 1a. FOUP 20 comprises a FOUP body 20a and a door (lid) 20b. Inside the FOUP body 20a, there is a space (storage space) for storing semiconductor wafers. The door 20b can be detached from and connected to the FOUP body 20a, and when connected, it is provided in a state that allows it to be opened and closed relative to the opening of the FOUP body 20a. The storage space of the FOUP body 20a communicates with the opening of the FOUP body 20a and is located inside the opening of the FOUP body 20a. Furthermore, the FOUP body 20a is provided with a flange 20c. The flange 20c is the part that grips (holds) the FOUP 20 when it is transported by an OHT (Overhead Hoist Transport) or robot 3, etc. Note that the OHT grips not only the flange 20c but also the bottom surface of the FOUP 20. Flange 20c is an example of a part to be gripped.

[0016] For example, on the external part of the casing 1a of the load port 2, the FOUP 20 carried while being gripped by the flange 20c by the OHT is placed. When the FOUP 20 is placed on the load port 2 in this way, the shutter 2a provided at the opening 1b of the casing 1a rises. As a result, the FOUP 20 can be carried into the inside of the casing 1a from the opening 1b. That is, the FOUP 20 can be carried into the inside of the wafer storage container cleaning device 1. FIG. 2 is a side view showing an example of the load port 2 and the first inspection unit 7 according to the embodiment. And, as shown in FIG. 2, the FOUP 20 is slid in the direction indicated by the arrow 2b by the slide device 20d of the load port 2. As a result, the FOUP 20 is carried into the inside of the casing 1a. An example of the slide by the slide device 20d will be described. For example, a pin provided in the slide device 20d is inserted into a hole provided in the bottom (mounting surface) 20e of the FOUP 20, whereby the mounting surface 20e of the FOUP 20 is fixed to the slide device 20d. And, in such a state, when the slide device 20d is slid in the direction of the arrow 2b, the FOUP 20 is also slid along with it. As a result, the FOUP 20 is placed on a predetermined portion inside the casing 1a of the load port 2. When the FOUP 20 is carried into the inside of the casing 1a in this way, the shutter 2a descends and the opening 1b of the casing 1a is closed. The slide device 20d descends to a position lower than the lower end of the shutter 2a (the mounting surface 20e of the FOUP 20) together with the pin and returns to the original position outside the casing 1a.

[0017] The robot 3 conveys the FOUP 20 to each part while gripping the flange 20c of the FOUP 20. The robot 3 includes a robot arm 3a and a robot hand 3b. The robot 3 conveys the FOUP 20 to each part by expanding and contracting or rotating the robot arm 3a while the robot hand 3b grips the flange 20c.

[0018] The disassembly / connection stage 4 disassembles the FOUP 20 into the FOUP body 20a and the door 20b, or connects the FOUP body 20a and the door 20b. A latch key 4a is provided on the disassembly / connection stage 4. When this latch key 4a is inserted into a latch hole provided in the door 20b of the FOUP 20 and rotated, the FOUP 20 is disassembled (separated) into the FOUP body 20a and the door 20b, or the FOUP body 20a and the door 20b are connected.

[0019] The cleaning tank 5 is a tank for cleaning the FOUP 20. For example, the cleaning tank 5 cleans at least the storage space containing the wafers within the entire FOUP 20. The cleaning tank 5 is an example of a cleaning unit. For example, the cleaning tank 5 comprises a cleaning tank body and a lid. The cleaning tank body has an opening at the top, through which the FOUP body 20a is brought into the interior of the cleaning tank body. Inside the cleaning tank body, there is a first holding part for holding the brought-in FOUP body 20a. The lid is located above the cleaning tank body and opens and closes relative to the opening of the cleaning tank body by the operation of an air cylinder. Inside the lid, there is a second holding part capable of holding the door 20b.

[0020] In addition, inside the cleaning tank body, nozzles for supplying a liquid used when cleaning the FOUP body 20a and the door 20b are provided. Also, inside the cleaning tank body, a rotating part for rotating the FOUP body 20a and the door 20b held by the first holding part and the second holding part is provided. By injecting the liquid from the nozzles onto the FOUP body 20a and the door 20b rotated by the rotating part, the FOUP 20 is cleaned. Further, an air blow nozzle for injecting gas is provided inside the cleaning tank body. After the cleaning process with the liquid, by injecting the gas from the air blow nozzle onto the FOUP body 20a and the door 20b, the FOUP body 20a and the door 20b are dried. Note that even during the drying process with the gas from the air blow nozzle, the FOUP body 20a and the door 20b are rotated by the rotating part. Also, it is possible to dry the liquid adhering to the FOUP body 20a and the door 20b by rotation by the rotating part without injecting gas from the air blow nozzle.

[0021] The vacuum chamber 6 is a chamber for vacuum-drying the FOUP 20. Inside the vacuum chamber 6, a holding part for holding the FOUP body 20a and the door 20b conveyed into the vacuum chamber 6, a halogen lamp, and a turbo pump capable of evacuating the inside of the vacuum chamber 6 are provided. The vacuum chamber 6 vacuum-dries the FOUP body 20a and the door 20b by heating them with a halogen lamp while evacuating the inside of the vacuum chamber 6 with a turbo pump in a state where the FOUP body 20a and the door 20b are held by the holding part.

[0022] The first inspection unit 7 inspects the condition of the flange 20c of the FOUP 20 to be cleaned, which has been brought into the casing 1a of the load port 2. For example, the camera 7f and illumination 7g of the first inspection unit 7, which will be described later, are located above the interior part of the casing 1a of the load port 2. As shown in Figure 2, the illumination 7g is positioned to illuminate the entire flange 20c of the FOUP 20 placed on the load port 2. The illumination 7g illuminates the entire flange 20c through a measurement window 7j formed in a predetermined part of the top plate 7i. For example, a ring illumination is used as the illumination 7g. The camera 7f is also positioned to have a field of view of the entire flange 20c of the FOUP 20 placed on the load port 2, as shown in Figure 2, and images the flange 20c through the measurement window 7j.

[0023] The inspection performed by the first inspection unit 7 as described above is referred to as the first inspection. For example, in the first inspection, the first inspection unit 7 determines whether the flange 20c is usable by determining whether the shape of the flange 20c is within the standard. In this context, if the flange 20c is usable, it means, for example, that the shape of the flange 20c is within the standard and that the flange 20c can be gripped by the robot 3 or OHT without falling off. On the other hand, if the flange 20c is not usable, it means that the shape of the flange 20c is not within the standard. In such a state, for example, the flange 20c cannot be properly gripped by the robot 3 or OHT (including cases where it can be gripped but is tilted), or if it deviates significantly from the standard (including cases where damage such as cracks have occurred in part of the flange 20c), it may fall off the robot 3 or OHT even if it can be gripped.

[0024] Furthermore, in the first inspection, the determination of whether or not the wafer is usable may be made not only by whether or not it conforms to a predetermined standard, but also by whether or not it is smaller than a predetermined arbitrary size. In other words, in the first inspection, if the wafer is smaller than a predetermined size (reference data), it is determined to be "unusable" because it may not be possible to grasp it with the robot 3 or OHT, or there is a possibility of it falling off. This predetermined size may be set for each type of FOUP 20 that is processed by the wafer storage container cleaning device 1, or it may be set in common for all types of FOUP 20 that are processed by the wafer storage container cleaning device 1.

[0025] Figure 3 shows an example of the configuration of the first inspection unit 7 according to the embodiment. As shown in Figure 3, the first inspection unit 7 includes a CPU (Central Processing Unit) 7a, a ROM (Read Only Memory) 7b, a RAM (Random Access Memory) 7c, an HDD (Hard Disk Drive) 7d, a communication interface 7e, a camera 7f, lighting 7g, and an ID reading unit 7h. These are connected via an internal bus.

[0026] The CPU 7a executes various processes while using the RAM 7c memory area as a temporary storage area for data used in various processes. The ROM 7b and HDD 7d store programs for executing various processes, as well as various databases and tables used when executing these processes.

[0027] The communication interface 7e is an interface for communicating with the communication interface 10e of the control unit 10, which will be described later. For example, the communication interface 7e is a network interface card or the like.

[0028] The lighting 7g is positioned to illuminate the flange 20c of the FOUP 20, which is placed on a predetermined part inside the casing 1a of the load port 2, from directly above (see Figure 2). The camera 7f is also positioned to photograph the flange 20c of the FOUP 20, which is placed on a predetermined part inside the casing 1a of the load port 2, from directly above (see Figure 2). The camera 7f photographs the flange 20c and transmits the image data obtained by photographing the flange 20c to the CPU 7a. The CPU 7a performs the first inspection described above by performing image processing on this image data. Note that since image processing is performed on image data obtained by photographing the flange 20c of the FOUP 20, which is placed on a predetermined part inside the casing 1a of the load port 2, the first inspection unit 7 may include "a predetermined part inside the casing 1a of the load port 2" as a component of the first inspection unit 7. The image processing performed by the CPU 7a will be described later.

[0029] The ID reading unit 7h reads the ID (Identification) of the FOUP20, which is the identification information of the FOUP20. The ID reading unit 7h is an example of a reading unit. For example, the ID reading unit 7h is a barcode scanner (barcode reader) that reads the barcode showing the individual identification number of the FOUP20 as the ID of the FOUP20 and transmits the individual identification number shown by the read barcode to the CPU 7a. Alternatively, for example, the ID reading unit 7h may be a reader that reads the individual identification number of the FOUP20 output as the ID of the FOUP20 from the RF tag provided on the FOUP20. The ID reading unit 7h then transmits the read individual identification number to the CPU 7a. When the CPU 7a receives the individual identification number, it controls the communication interface 7e to transmit the received individual identification number to the communication interface 10e of the control unit 10. As a result, the communication interface 7e transmits the individual identification number to the communication interface 10e of the control unit 10.

[0030] Returning to the explanation of Figure 1, the second inspection unit 8 inspects the condition of the storage space of the FOUP 20, which has been cleaned and vacuum-dried by the cleaning tank 5 and the vacuum tank 6.

[0031] The inspection performed by the second inspection unit 8 as described above is referred to as the second inspection. For example, in the second inspection, the second inspection unit 8 determines whether the storage space of the FOUP20 is usable by determining whether the shape of the storage space of the FOUP20 is within specifications. The case in which the storage space of the FOUP20 is usable means, for example, that the bump positions provided in the storage space of the FOUP20 and the shape of the shelves on which wafers are placed are within specifications, and that wafers can be stored normally in the storage space of the FOUP20. On the other hand, the case in which the storage space of the FOUP20 is not usable means, for example, that the bump positions provided in the storage space of the FOUP20 and the shape of the shelves on which wafers are placed are not within specifications, and that wafers cannot be stored normally in the storage space of the FOUP20, or that even if they can be stored, there is a possibility that the wafers will fall off the shelves. Alternatively, it means that the shape of the shelves is not within specifications (for example, the pitch between adjacent shelves above and below is too narrow), and there is a possibility that wafers above and below may come into contact with each other.

[0032] Furthermore, in the second inspection, the determination of whether a wafer is usable may be made not only by whether it meets the prescribed standards, but also by whether the amount of deviation from a predetermined arbitrary reference value (reference data) is within the allowable range. In other words, in the second inspection, if, for example, the amount of deviation of the bump position from a predetermined reference position exceeds the allowable range, the wafer may not be able to be stored, or even if it can be stored, it may fall out or come into contact with other wafers, so it is determined to be "unusable". These predetermined reference values ​​and allowable ranges may be set for each type of FOUP 20 to be processed by the wafer storage container cleaning device 1, or they may be set in common for all types of FOUP 20 to be processed by the wafer storage container cleaning device 1.

[0033] Figure 4 shows an example of the configuration of the second inspection unit 8 according to the embodiment. As shown in Figure 4, the second inspection unit 8 comprises a CPU 8a, a ROM 8b, a RAM 8c, an HDD 8d, a communication interface 8e, two cameras 8f and 8g, and an inspection stage 8h. Of these, the CPU 8a, ROM 8b, RAM 8c, HDD 8d, the communication interface 8e, and the two cameras 8f and 8g are connected via an internal bus.

[0034] The CPU 8a executes various processes while using the RAM 8c memory area as a temporary storage area for data used in various processes. The ROM 8b and HDD 8d store programs for executing various processes, as well as various databases and tables used when executing these processes.

[0035] The communication interface 8e is an interface for communicating with the communication interface 10e of the control unit 10, which will be described later. For example, the communication interface 8e is a network interface card.

[0036] As shown in Figure 1, cameras 8f and 8g are positioned opposite the opening of the FOUP body 20a placed on the inspection stage 8h. Cameras 8f and 8g are also positioned to capture images of the storage space of the FOUP body 20a placed on the inspection stage 8h. Cameras 8f and 8g capture images of the storage space of the FOUP 20 and transmit the image data obtained by capturing images of the storage space of the FOUP body 20a to the CPU 8a. The CPU 8a performs the second inspection described above by executing image processing on this image data. The image processing performed by the CPU 8a will be described later.

[0037] The robot 3 places the FOUP body 20a on the inspection stage 8h so that the flange 20c of the FOUP body 20a faces upward and the opening faces the cameras 8f and 8g. At this time, the FOUP body 20a is positioned by positioning pins provided on the inspection stage 8h and placed on the inspection stage 8h.

[0038] The inspection stage 8h can be raised and lowered by a lifting mechanism (not shown), which changes the relative positional relationship between the opening of the FOUP body 20a and the cameras 8f and 8g. As a result, the field of view of cameras 8f and 8g moves sequentially relative to the entire storage space of the FOUP body 20a, which is the target of imaging, and images are captured sequentially.

[0039] Returning to the explanation of Figure 1, the unload port 9 transports the cleaned and vacuum-dried FOUP 20, which has been placed inside the casing 1a of the unload port 9 by the robot 3, to the outside of the casing 1a.

[0040] For example, the FOUP 20, transported by the robot 3, is placed inside the casing 1a of the unload port 9. When the FOUP 20 is placed in the unload port 9 in this way, the shutter 9a provided at the opening 1c of the casing 1a rises. This makes it possible to transport the FOUP 20 out of the casing 1a through the opening 1c. In other words, the FOUP 20 becomes ready to be transported out of the wafer storage container cleaning device 1. Then, the FOUP 20 is slid out of the casing 1a by the sliding device of the unload port 9 (which has the same mechanism as the load port 2) in the direction indicated by the arrow 9b. Once the FOUP 20 has been transported out of the casing 1a in this way, the shutter 9a descends and the opening 1c of the casing 1a is closed.

[0041] Here, based on the determination results from the first inspection unit 7 and the second inspection unit 8, the control unit 10 sends a signal to an external device (a server that centrally manages all FOUPs, as described later) indicating that if the FOUP 20 is usable, it should be transported to the "usable FOUP stocker". Based on this signal, transport devices such as OHTs in the factory are controlled, and the FOUP 20 is transported to the "usable FOUP stocker". On the other hand, based on the determination results from the first inspection unit 7 and the second inspection unit 8, the control unit 10 sends a signal to an external device indicating that if the FOUP 20 is not usable, it should be transported to the "unusable FOUP stocker". Based on this signal, transport devices in the factory are controlled, and the FOUP 20 is transported to the "unusable FOUP stocker". As a result, only usable FOUPs 20 are transported to the "usable FOUP stocker", and only unusable FOUPs 20 are transported to the "unusable FOUP stocker". The "usable FOUP stocker" is an example of the first stocker. Furthermore, "unusable FOUP storage containers" are an example of a second type of storage container.

[0042] Alternatively, the control unit 10 may rewrite the RF tag information on the FOUP 20 based on the determination results of the first inspection unit 7 and the second inspection unit 8, and assign information to each FOUP 20 indicating whether it should be transported to the aforementioned "usable FOUP stocker" or to the "unusable FOUP stocker," and based on this, transport devices within the factory may transport the FOUPs to the respective stockers.

[0043] Here, the control unit 10 transmits a signal to an external device indicating which stocker the FOUP 20 should be transported to. In this case, the external device directly controls the transport of the FOUP 20, but transmitting a transport instruction for the FOUP 20 to another control unit (transmitting a signal indicating the destination) is equivalent to controlling the transport of the FOUP (wafer storage container) 20 to either the first stocker or the second stocker.

[0044] The control unit 10 controls the operation of the entire wafer storage container cleaning apparatus 1. For example, the control unit 10 controls the load port 2, robot 3, disassembly / combination stage 4, cleaning tank 5, vacuum tank 6, first inspection unit 7, second inspection unit 8, and unload port 9, thereby operating the load port 2, robot 3, disassembly / combination stage 4, cleaning tank 5, vacuum tank 6, first inspection unit 7, second inspection unit 8, and unload port 9 as described above.

[0045] Figure 5 shows an example of the configuration of the control unit 10 according to the embodiment. As shown in Figure 5, the control unit 10 includes a CPU 10a, a ROM 10b, a RAM 10c, an HDD 10d, and a communication interface 10e. These are connected via an internal bus.

[0046] The CPU 10a executes various processes while using the memory area of ​​RAM 10c as a temporary storage area for data used in various processes. The processes executed by CPU 10a will be described later. ROM 10b and HDD 10d store programs for executing various processes, as well as various databases and tables used when executing these processes.

[0047] In this embodiment, for example, ROM10b or HDD10d pre-stores an inspection table in which records are registered for each ID, in which a FOUP ID (individual identification number), a first inspection data corresponding to the FOUP indicated by the ID, and a second inspection data corresponding to the FOUP indicated by the ID are associated.

[0048] The contents of the inspection table will be explained in detail. For example, the standard data regarding the flange shape differs depending on the type of FOUP. The standard data regarding the flange shape is data that indicates the shape of the flange, has a certain width, and conforms to standards. In this embodiment, the standard data regarding the flange shape corresponding to the type of FOUP indicated by the ID is registered in the inspection table as the first inspection data, associated with the ID. The first inspection data is used in the first inspection by the first inspection unit 7.

[0049] Furthermore, for example, the standard data regarding the shape of the storage space of a FOUP differs depending on the type of FOUP. The standard data regarding the shape of the storage space of a FOUP is data that indicates the shape of the storage space of a FOUP, has a certain width, and conforms to standards. In this embodiment, the standard data regarding the shape of the storage space of a FOUP corresponding to the type of FOUP indicated by the ID is registered in the inspection table as second inspection data, associated with the ID. The second inspection data is used in the second inspection by the second inspection unit 8.

[0050] The communication interface 10e communicates with the aforementioned communication interfaces 7e and 8e, as well as with external devices connected to the wafer storage container cleaning device 1 via a network. For example, the communication interface 10e is a network interface card.

[0051] Next, an example of a process performed by the wafer storage container cleaning apparatus 1 will be described. Figure 6 is a flowchart showing an example of the flow of a process performed by the wafer storage container cleaning apparatus 1 according to this embodiment. The process shown in Figure 6 is performed when a FOUP 20 to be cleaned is placed on the external part of the casing 1a of the load port 2. Note that the process shown in Figure 6 is a process performed by each part under the control of, for example, the control unit 10.

[0052] As shown in Figure 6, first, the load port 2 loads the FOUP 20, which is placed on the outside of the casing 1a of the load port 2, into the inside of the casing 1a (step S101).

[0053] Next, the ID reading unit 7h of the first inspection unit 7 reads the ID (individual identification number) of the FOUP 20 placed on a predetermined part inside the casing 1a of the load port 2 (step S102). The read individual identification number is transmitted to the control unit 10 as described above. Then, when the communication interface 10e of the control unit 10 receives the individual identification number, it transmits the received ID to the CPU 10a.

[0054] Then, when the CPU 10a of the control unit 10 receives an ID, it refers to the registered contents of the inspection table described above, identifies the first inspection data and the second inspection data associated with the received ID, and acquires the identified first inspection data and the second inspection data (step S103). The CPU 10a controls the communication interface 10e to transmit the acquired first inspection data to the first inspection unit 7. The CPU 10a also controls the communication interface 10e to transmit the acquired second inspection data to the second inspection unit 8. As a result, the CPU 7a of the first inspection unit 7 can perform processing in the first inspection using the first inspection data transmitted from the communication interface 10e. The CPU 8a of the second inspection unit 8 can also perform processing in the second inspection using the second inspection data transmitted from the communication interface 10e.

[0055] Next, the CPU 7a of the first inspection unit 7 performs image processing on the image data obtained when the flange 20c is photographed by the camera 7f, and uses the first inspection data to determine whether or not the flange 20c is usable (step S104).

[0056] Let's explain an example of the specific processing in step S104. For example, in step S104, the CPU 7a performs image processing on the image data obtained by the camera 7f to obtain the shape of the flange 20c depicted in the image data. Then, the CPU 7a determines whether the flange 20c is usable by determining whether the shape of the flange 20c obtained by the image processing falls within the specifications for the flange shape indicated in the first inspection data.

[0057] If it is determined that flange 20c is unusable (step S104: No), the CPU 10a of the control unit 10 controls the transport of FOUP 20 to the "unusable FOUP stocker" (step S105).

[0058] Let's describe an example of the specific processing in step S105. For example, in step S105, the CPU 10a controls the robot 3 to transport the FOUP 20, which is placed on a predetermined part inside the casing 1a of the load port 2, to a predetermined part inside the casing 1a of the unload port 9. As a result, the FOUP 20 is placed on a predetermined part inside the casing 1a of the unload port 9 by the robot 3. Then, the CPU 10a controls the unload port 9 so that the FOUP 20 is transported to the outside of the casing 1a. At this time, the CPU 10a sends a signal to an external device to transport the FOUP 20 to an "unavailable FOUP stocker". As a result, a transport device such as an OHT in the factory, which is controlled by the external device, transports the FOUP 20 to an "unavailable FOUP stocker".

[0059] Next, the CPU 10a associates the ID with the result of the first inspection and stores it in the HDD 10d (step S106). If the results of past first inspections are stored in the HDD 10d in association with the ID, the CPU 10a stores the result of the current first inspection in the HDD 10d as history, associated with the ID. The results of the first inspection include the shape of the flange 20c obtained by image processing, and information indicating whether the flange 20c is usable or not. When this information stored in the HDD 10d is displayed on the display, the user can easily grasp the time-series changes in the state of the flange 20c of the FOUP 20 indicated by the ID. Therefore, according to this embodiment, information that allows the user to easily grasp the time-series changes in the state of the flange 20c of the FOUP 20 indicated by the ID can be stored in the HDD 10d. By understanding the changes in the flange 20c, which is the object of inspection, over time, it is possible to determine the average lifespan for each type of FOUP, for example, and to perform cleaning treatment on FOUPs that are in a reliably usable condition, as well as to transport them to a "stocker for usable FOUPs."

[0060] The CPU 10a then controls the communication interface 10e to output information associating the ID with the result of the first inspection to an external device (step S107), and terminates the process shown in Figure 6. Here, the external device is, for example, a server that centrally manages all FOUP 20s in the factory. When such an external device receives information associating the ID with the result of the first inspection, it stores the result of the first inspection as a history, associated with the ID, in a storage unit such as an HDD. The external device then displays this information stored in the HDD on a display. At this time, the user can easily understand the state of the flange 20c of the FOUP 20 indicated by the ID displayed on the display. The information associating the ID with the result of the first inspection is an example of the first information.

[0061] On the other hand, if it is determined that the flange 20c is usable (step S104: Yes), the CPU 10a of the control unit 10 controls the robot 3 to transport the FOUP 20 from the first inspection unit 7 to the cleaning tank 5 via the disassembly / connection stage 4 (step S108).

[0062] An example of the specific processing in step S108 will be described. In step S108, first, the CPU 10a controls the robot 3 to transport the FOUP 20, which is placed on a predetermined part inside the casing 1a of the load port 2, to the disassembly / connection stage 4. As a result, the FOUP 20 transported to the disassembly / connection stage 4 is disassembled into the FOUP body 20a and the door 20b by the disassembly / connection stage 4. Then, the CPU 10a controls the robot 3 to transport the FOUP body 20a into the inside of the cleaning tank body of the cleaning tank 5. The CPU 10a also controls the robot 3 to transport the door 20b to the lid of the cleaning tank 5. As a result, the first holding part provided inside the cleaning tank body of the cleaning tank 5 holds the FOUP body 20a, and the second holding part provided inside the lid of the cleaning tank 5 holds the door 20b. Furthermore, the height of the cleaning tank body of the cleaning tank 5 is such that when the door 20b is provided on the second holding part on the inside of the lid of the cleaning tank 5, and the first holding part of the cleaning tank body holds the FOUP body 20a and the lid is closed, the FOUP body 20a and the door 20b do not come into contact.

[0063] Then, the cleaning tank 5 cleans and dries the FOUP 20 (step S109). Specifically, in step S109, the FOUP 20 is cleaned by spraying liquid from a nozzle onto the FOUP body 20a and door 20b, which are rotated by the rotating part. Furthermore, after the cleaning process, the FOUP body 20a and door 20b are dried by spraying gas from an air blow nozzle onto them.

[0064] Then, the CPU 10a controls the robot 3 to transport the FOUP body 20a and door 20b from the cleaning tank 5 to the vacuum tank 6 (step S110). As a result, the FOUP body 20a and door 20b are transported into the vacuum tank 6 by the robot 3.

[0065] Then, the vacuum chamber 6 vacuum-dries the FOUP body 20a and door 20b (step S111). The vacuum chamber 6 is heated with a halogen lamp while being vacuumed by a turbo pump, vacuum-drying the FOUP body 20a and door 20b placed inside the vacuum chamber 6, and removing any water droplets or remaining deposits that could not be dried by drying with the air blow nozzle in the cleaning tank 5.

[0066] The CPU 10a then controls the robot 3 to transport the FOUP body 20a from the vacuum chamber 6 to the inspection stage 8h of the second inspection unit 8 (step S112). As a result, the FOUP body 20a is positioned relative to the inspection stage 8h by the robot 3 and placed on the inspection stage 8h. At this time, the door 20b is placed by the robot 3 so that its latch hole contacts the disassembly / connection stage 4.

[0067] Next, the CPU 8a of the second inspection unit 8 performs image processing on the image data obtained by cameras 8f and 8g capturing images of the storage space of the FOUP main unit 20a, and uses the second inspection data to determine whether or not the storage space of the FOUP main unit 20a is usable (step S113).

[0068] Let's explain an example of the specific processing in step S113. For example, in step S113, the CPU 8a performs image processing on the image data obtained by cameras 8f and 8g to obtain the shape of the storage space of the FOUP main unit 20a depicted in the image data. Then, the CPU 8a determines whether the storage space of the FOUP main unit 20a is usable by determining whether the shape of the storage space obtained by the image processing falls within the specifications for the shape of the storage space indicated by the second inspection data.

[0069] If it is determined that the storage space for the FOUP body 20a is unavailable (step S113: No), the CPU 10a proceeds to step S105 and executes processing in each step from step S105 onward. However, if a negative determination is made in step S113 (step S113: No), in step 105, the CPU 10a controls the robot 3 to transport the FOUP body 20a, which is placed on the inspection stage 8h, to the disassembly / connection stage 4. As a result, the door 20b, which was already placed on the disassembly / connection stage 4, and the FOUP body 20a, which was transported to the disassembly / connection stage 4 after the completion of the second inspection, are connected by the disassembly / connection stage 4. Then, the CPU 10a controls the robot 3 to transport the FOUP 20, which is located on the disassembly / connection stage 4, to a predetermined part inside the casing 1a of the unload port 9. As a result, the FOUP 20 is placed by the robot 3 on a predetermined part inside the casing 1a of the unload port 9. The CPU 10a then controls the unload port 9 so that the FOUP 20 is discharged to the outside of the casing 1a. At this time, the CPU 10a sends a signal to an external device to transport the FOUP 20 to an "unavailable FOUP stocker". As a result, a transport device such as an OHT in the factory, which is controlled by the external device, transports the FOUP 20 to the "unavailable FOUP stocker".

[0070] Furthermore, if a negative result is obtained in step S113 (step S113: No), in step 106, the CPU 10a performs the following additional processing in addition to the processing in step S106 described above. For example, the CPU 10a associates the ID with the result of the second inspection and stores it in the HDD 10d. If the results of past second inspections are stored in the HDD 10d and associated with the ID, the CPU 10a stores the result of the current second inspection in the HDD 10d as history and associated with the ID. The results of the second inspection include the shape of the storage space of the FOUP main unit 20a obtained by image processing, and information indicating whether the storage space of the FOUP main unit 20a is usable or not. When this information stored in the HDD 10d is displayed on the display, the user can easily grasp the time-series changing state of the storage space of the FOUP main unit 20a of the FOUP 20 indicated by the ID. Therefore, according to this embodiment, information that allows the user to easily grasp the time-series changes in the storage space of the FOUP body 20a of the FOUP 20 indicated by the ID can be stored in the HDD 10d. By grasping the changes over time of the FOUP body 20a that is the subject of inspection, it is possible to grasp, for example, the average lifespan for each type of FOUP, and to reliably perform cleaning processing on FOUPs that are in a usable state, and to transport them to a "stocker for usable FOUPs". Alternatively, if the inspection result changes due to processing in a process before being brought into the wafer storage container cleaning apparatus 1, the processing content performed in the wafer storage container cleaning apparatus 1 can be changed when the next FOUP that has undergone similar processing is brought into the wafer storage container cleaning apparatus 1, such as changing the cleaning processing time or the type of cleaning solution in the cleaning tank 5, or changing the vacuum drying processing time in the vacuum tank 6.

[0071] Furthermore, if a negative result is obtained in step S113 (step S113: No), in step 107, the CPU 10a performs the following processing in addition to the processing in step S107 described above. For example, the CPU 10a controls the communication interface 10e to output information associating the ID with the result of the second inspection to an external device. When the external device receives the information associating the ID with the result of the second inspection, it stores the result of the second inspection as a history, associated with the ID, in a storage unit such as an HDD. The external device then displays this information stored in the HDD on a display. At this time, the user can easily grasp the state of the storage space of the FOUP body 20a of the FOUP 20 indicated by the ID displayed on the display. The information associating the ID with the result of the second inspection is an example of the second information.

[0072] As mentioned above, the first and second inspection results are stored on an external server that centrally manages all FOUPs. The transport equipment within the factory may be controlled based on the data stored on this server. In other words, FOUPs determined to be "usable" and those determined to be "unusable" based on the first and second inspection results are transported to a common stocker without distinction, and the transport equipment within the factory is controlled so that only FOUPs determined to be "usable" are used. In this case, the first and second stockers are virtually provided within the server. That is, the control unit 10 controls the transport of "usable" FOUPs to a virtually provided first stocker and "unusable" FOUPs to a virtually provided second stocker, based on the results of the first and second inspections. Alternatively, as mentioned above, the first and second information, including the RF tag rewriting results, may be stored within the server, and the data may be stored separately in virtual first and second stockers within the server. In this case as well, it would be acceptable to physically transport all FOUPs to a common stocker.

[0073] On the other hand, if it is determined that the storage space for the FOUP unit 20a is available (step S113: Yes), the CPU 10a controls the transport of the FOUP 20 to an "available FOUP stocker" (step S114).

[0074] An example of the specific processing in step S114 will be described. For example, in step S114, first, the CPU 10a controls the robot 3 to transport the FOUP body 20a, which is placed on the inspection stage 8h, to the disassembly / connection stage 4. As a result, the door 20b, which was already placed on the disassembly / connection stage 4, and the FOUP body 20a, which was transported to the disassembly / connection stage 4 after the completion of the second inspection, are connected by the disassembly / connection stage 4. Then, the CPU 10a controls the robot 3 to transport the FOUP 20, which is located on the disassembly / connection stage 4, to a predetermined part inside the casing 1a of the unload port 9. As a result, the FOUP 20 is placed by the robot 3 on a predetermined part inside the casing 1a of the unload port 9. Then, the CPU 10a controls the unload port 9 so that the FOUP 20 is unloaded to the outside of the casing 1a. At this time, the CPU 10a transmits a signal to an external device to transport the FOUP 20 to a "stocker for usable FOUPs". This allows the conveying equipment, such as the OHT, to transport the FOUP20 to a "usable FOUP stocker".

[0075] Then, CPU 10a executes the processes in steps S115 and S116 and terminates the process shown in Figure 6. For example, in step S115, CPU 10a executes the same process as in step 106 when a negative result is obtained in step S113 (step S113: No). Also, in step S116, CPU 10a executes the same process as in step 107 when a negative result is obtained in step S113 (step S113: No).

[0076] The wafer storage container cleaning apparatus 1 according to the embodiment has been described above. In this embodiment, the robot 3 transports the FOUP 20 from the first inspection unit 7 to the cleaning tank 5, and transports the FOUP 20 from the cleaning tank 5 to the second inspection unit 8. The control unit 10 controls the robot 3 to transport the FOUP 20 from the first inspection unit 7 to the cleaning tank 5 if it determines, based on the results of the first inspection by the first inspection unit 7, that the FOUP 20 (specifically the flange 20c) is in a usable state. The control unit 10 also controls the robot 3 to transport the FOUP 20 from the first inspection unit 7 to a location other than the cleaning tank 5 if it determines, based on the results of the first inspection by the first inspection unit 7, that the FOUP 20 (specifically the flange 20c) is not in a usable state.

[0077] Therefore, the wafer storage container cleaning apparatus 1 cleans the FOUP 20 that is in a usable condition, without unnecessarily cleaning FOUP 20 whose flange 20c is not in a usable condition. Thus, according to the wafer storage container cleaning apparatus 1 of this embodiment, it is possible to inspect the FOUP 20 and clean the FOUP 20 efficiently.

[0078] Furthermore, as described above, the OHT grips not only the flange 20c but also the bottom surface of the FOUP 20. Therefore, even if the flange 20c is not in a usable state, it is rare for the FOUP 20 to fall off the OHT. However, in the wafer storage container cleaning apparatus 1 according to this embodiment, the robot 3 grips only the flange 20c when transporting the FOUP 20 or FOUP body 20a. Therefore, in the wafer storage container cleaning apparatus 1 according to this embodiment, the first inspection unit 7 inspects the condition of the flange 20c before the process in which the robot 3 transports the FOUP 20 or FOUP body 20a. If the flange 20c is not in a usable state, the FOUP 20 is transported to the "unusable FOUP stocker" without proceeding to the process in which the robot 3 transports the FOUP 20 or FOUP body 20a. Therefore, according to the wafer storage container cleaning apparatus 1 according to this embodiment, the transport of the FOUP 20 or FOUP body 20a by the robot 3 within the wafer storage container cleaning apparatus 1 can be performed more reliably and safely.

[0079] Furthermore, if the control unit 10 determines, based on the results of the second inspection by the second inspection unit 8, that the FOUP 20 (specifically, the storage space for the FOUP 20) is in a usable state, it controls the transport of the FOUP 20 to a "usable FOUP stocker". If the control unit 10 determines, based on the results of the second inspection by the second inspection unit 8, that the FOUP 20 (specifically, the storage space for the FOUP 20) is not in a usable state, it controls the transport of the FOUP 20 to a "non-usable FOUP stocker" that is different from the "usable FOUP stocker".

[0080] Therefore, according to the wafer storage container cleaning apparatus 1 of this embodiment, it is possible to physically / virtually separate FOUP20 that are in a usable state from FOUP20 that are not in a usable state. As a result, FOUP20 that are in a usable state can be provided to the process after the FOUP20 is removed from the wafer storage container cleaning apparatus 1, so that wafers can be properly stored in the FOUP20.

[0081] Furthermore, based on the ID, the control unit 10 identifies first inspection data that will be used as a criterion for determining whether the flange 20c of the FOUP 20 is usable or not when inspecting in the first inspection unit 7. Furthermore, based on the ID, the control unit 10 identifies second inspection data that will be used as a criterion for determining whether the storage space of the FOUP 20 is usable or not when inspecting in the second inspection unit 8.

[0082] Thus, according to the wafer storage container cleaning apparatus 1 of this embodiment, the first inspection data and the second inspection data are identified based on the ID. Therefore, the appropriate first inspection data and the second inspection data corresponding to the FOUP 20 to be cleaned can be identified more accurately.

[0083] Furthermore, the control unit 10 outputs to the outside information relating the ID to the result of the first inspection by the first inspection unit 7, and information relating the ID to the result of the second inspection by the second inspection unit 8.

[0084] Therefore, according to the wafer storage container cleaning apparatus 1 of this embodiment, information that allows for easy understanding of the state of the flange 20c and the state of the storage space can be output to the outside.

[0085] In addition, the first inspection unit 7 and the second inspection unit 8 each have a CPU 7a and a CPU 8a, respectively, and perform image processing and judgment. However, the system is not limited to this, and the first inspection unit 7 and the second inspection unit 8 may only perform detection (imaging) of the object to be inspected, while the control unit 10 performs the inspection (image processing and judgment). In this case, the communication interface 10e of the control unit 10 will function as an interface with an external device outside the wafer storage container cleaning apparatus 1.

[0086] Furthermore, in the above embodiment, the cleaning section is exemplified as a cleaning tank 5 in which cleaning is performed with liquid followed by drying with gas from an air blow nozzle, but it is not limited to this, and cleaning with liquid only may be performed.

[0087] In the above embodiment, after the inspection by the second inspection unit 8 is completed, the FOUP body 20a and the door 20b are connected in the disassembly / connection stage 4 and transported from the wafer storage container cleaning device 1 to the stocker via the unload port 9, but the invention is not limited to this. Within the wafer storage container cleaning device 1, nitrogen gas may be injected into the interior (storage space) of the FOUP 20 with the FOUP body 20a and door 20b connected, through a purge hole provided in the bottom of the FOUP 20, to perform an inspection to confirm the airtightness of the FOUP 20. This may be done, for example, in the disassembly / connection stage, or in the unload port 9. Alternatively, it may be done on a temporary stand (not shown) provided inside the casing 1a.

[0088] Furthermore, the disassembly / connection stage does not necessarily have to be provided solely for the purpose of disassembling and connecting the FOUP body 20a and the door 20b. For example, multiple buffer tables may be provided for placing multiple FOUPs 20 that have finished processing by the wafer storage container cleaning device 1 and are waiting to be unloaded. These multiple buffer tables may be equipped with latch keys 4a so that they also function as a disassembly / connection stage.

[0089] Furthermore, while the example given shows that FOUP20s determined to be "not in a usable condition" in the first inspection are transported to the unload port 9, which is a different location from the washing tank 5, this is not limited to this, and other locations are also possible. For example, it could be any other location provided on the casing 1a, such as the multiple disassembly / connection stages 4 mentioned above, the temporary storage table, or the buffer table.

[0090] (modified version) Next, a modified version of the above-described embodiment will be explained. For example, in the above-described embodiment, the case was described in which the camera 7f photographs the flange 20c of the FOUP 20 placed on a predetermined part inside the casing 1a of the load port 2. However, in the modified version, the camera 7f may photograph the flange 20c of the FOUP 20 before the FOUP 20 is loaded into the casing 1a. That is, the camera 7f may photograph the flange 20c of the FOUP 20 placed on a predetermined part outside the casing 1a of the load port 2. If it is determined that the flange 20c is not usable (step S104: No), the CPU 10a of the control unit 10 may control the transport of the FOUP 20 to the "stocker for unusable FOUPs" without loading the FOUP 20 into the casing 1a. [Explanation of Symbols]

[0091] 1. Wafer storage container cleaning device 3 Robots 5. Washing tank 7. First Inspection Department 8. Second Inspection Department 10 Control Unit

Claims

1. A first inspection unit that inspects the condition of the gripping portion of the wafer storage container, A wafer storage container includes a cleaning unit that cleans at least the storage space in which wafers are stored, A second inspection unit for inspecting the condition of the storage space, At a minimum, a robot that transports wafer storage containers from the first inspection unit to the cleaning unit, and transports wafer storage containers from the cleaning unit to the second inspection unit, A control unit for controlling the robot, Equipped with, The control unit controls the robot to transport the wafer storage container from the first inspection unit to the cleaning unit if it determines, based on the results of the inspection by the first inspection unit, that the wafer storage container is in a usable state, and controls the robot to transport the wafer storage container from the first inspection unit to a location different from the cleaning unit if it determines, based on the results of the inspection by the first inspection unit, that the wafer storage container is not in a usable state. Wafer storage container cleaning device.

2. The control unit controls the transport of the wafer storage container to the first stocker if it determines, based on the results of the inspection by the second inspection unit, that the wafer storage container is in a usable state, and controls the transport of the wafer storage container to a second stocker different from the first stocker if it determines, based on the results of the inspection by the second inspection unit, that the wafer storage container is not in a usable state. A wafer storage container cleaning apparatus according to claim 1.

3. The wafer storage container is further equipped with a reading unit for reading identification information provided in the wafer storage container, The control unit identifies, based on the identification information, first inspection data used as a criterion for determining whether the gripping portion of the wafer storage container is usable when inspecting in the first inspection unit, and second inspection data used as a criterion for determining whether the storage space of the wafer storage container is usable when inspecting in the second inspection unit. A wafer storage container cleaning apparatus according to claim 1.

4. The wafer storage container is further equipped with a reading unit for reading identification information provided in the wafer storage container, The control unit outputs to the outside first information, which associates the identification information with the results of the inspection by the first inspection unit, and second information, which associates the identification information with the results of the inspection by the second inspection unit. A wafer storage container cleaning apparatus according to claim 1 or 2.

5. The wafer storage container further includes a disassembly / connection stage for disassembling and connecting the wafer storage container body and the door, The control unit, Prior to cleaning by the cleaning unit, the robot is controlled to transport the wafer storage container to the disassembly / connection stage, and the disassembly / connection stage is controlled to disassemble the wafer storage container into the wafer storage container body and the door. After cleaning by the cleaning unit, the robot is controlled to transport the door to the disassembly / connection stage; after inspection by the second inspection unit, the robot is controlled to transport the wafer storage container body to the disassembly / connection stage; and the disassembly / connection stage is controlled to connect the wafer storage container body and the door at the disassembly / connection stage. The wafer storage container cleaning apparatus according to claim 2, characterized in that the robot is controlled to temporarily place the wafer storage container awaiting transfer to the first stocker or the second stocker on the disassembly / connection stage.

6. The wafer storage container cleaning apparatus according to claim 5, characterized in that it is provided with a plurality of disassembly / connection stages.

7. A first inspection step is performed to inspect the condition of the gripping portion of the wafer storage container, A step of cleaning the storage space of the wafer storage container after the first inspection has been completed, The process includes a second step of performing an inspection to check the condition of the storage space in the wafer storage container after cleaning the storage space, A method for cleaning wafer storage containers, characterized in that the step of cleaning the storage space is performed only for wafer storage containers that have been determined to be in a usable state based on the inspection results in the first inspection step.

8. The wafer storage container cleaning method according to claim 7, characterized in that, in the step of performing the first inspection, if it is determined that the wafer storage container is not in a usable state, the wafer storage container is transported by a robot to a position different from the position in which the storage space of the wafer storage container is cleaned.

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