Wafer housing container cleaning device

Abstract

To provide a wafer housing container cleaning device which suppresses contamination of a wafer housing container cleaned by a cleaning tank.SOLUTION: A wafer housing container cleaning device comprises: a cleaning tank main body 5a that has an open part on an upper surface, and can house a wafer housing container 20 therein; a lid part 5b that opens / closes the open part of the cleaning tank main body 5a; a mounting part 5c that can mount a shell 20a thereon in a state where a shell open part of the shell 20a is directed below; a first cleaning liquid discharge part 5d that discharges a cleaning liquid to an inner surface of the shell 20a in a shell mounting state; and a second cleaning liquid discharge part 5e that is provided on an outside of the shell 20a, and discharges the cleaning liquid to an outer surface of the shell 20a. A discharge port of a nozzle 5m for discharging the cleaning liquid in a horizontal direction of the first cleaning liquid discharge part 5d and a discharge port of a nozzle 5o of the second cleaning liquid discharge part 5e face each other so as to be able to discharge the cleaning liquid toward the other discharge port from one discharge port in a shell non-mounting state that is a state where the shell 20a is not mounted on the mounting part 5c.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE An embodiment of the present invention relates to a wafer container cleaning apparatus. [Background technology]

[0002] There are wafer storage containers such as FOUPs (Front Opening Unified Pods) and FOSBs (Front Opening Shipping Boxes) that store wafers (semiconductor wafers). For example, a FOUP has a shell with an opening and a door attached to the opening. Inside the shell, multiple shelves are formed to hold multiple wafers.

[0003] Semiconductor devices are formed on wafers through various processes. When moving between processes, the wafers are transported in a wafer container. When a wafer container is used repeatedly in multiple processes, particles and chemical contaminants may adhere to the inside of the wafer container (e.g., inside the shell). If these contaminants re-adhere to the wafers stored in the wafer container, the result will be a lower yield of semiconductor devices. For this reason, after a wafer container has been used several times, it is necessary to clean the wafer container and return it to a clean state.

[0004] For example, one proposed technology for cleaning FOUPs is to house the shell and door in a single cleaning tank, where the shell and door are cleaned and dried. The cleaned and dried shell and door are then removed from the cleaning tank, and the next shell and door are then loaded into the cleaning tank. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2005-109523 A Summary of the Invention [Problem to be solved by the invention]

[0006] As described above, contaminants are attached to the inside of the wafer container. Therefore, when the inside of the wafer container is being cleaned, the contaminants may adhere to the cleaning liquid supply unit that supplies cleaning liquid to the inside of the wafer container. If the next wafer container is cleaned with the cleaning liquid supply unit still having contaminants attached to it, the contaminants attached to the cleaning liquid supply unit may adhere to the wafer container and contaminate the wafer container.

[0007] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a wafer container cleaning apparatus capable of suppressing contamination of a wafer container. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems and achieve the object, a wafer storage container cleaning apparatus according to one aspect of the present invention is a wafer storage container cleaning apparatus for cleaning a wafer storage container having a shell with a shell opening and a door attached to the shell opening, the apparatus comprising: a cleaning tank body which is a container having an opening on an upper surface and capable of accommodating the wafer storage container therein; a lid part which is provided on the opening side of the cleaning tank body and which opens and closes the opening of the cleaning tank body; and a mounting part which is provided inside the cleaning tank body and on which the shell can be placed with the shell opening facing downward. a first cleaning liquid discharge portion provided inside the shell in a shell-placed state in which the shell is placed by the placement portion and discharges cleaning liquid onto the inner surface of the shell, and a second cleaning liquid discharge portion provided outside the shell in the shell-placed state and discharges cleaning liquid onto the outer surface of the shell, wherein the discharge outlet of the first cleaning liquid discharge portion and the discharge outlet of the second cleaning liquid discharge portion face each other so that cleaning liquid can be discharged from one outlet to the other outlet in a shell-unplaced state in which the shell is not placed by the placement portion. Effect of the Invention

[0009] According to one aspect of the present invention, it is possible to provide a wafer container cleaning apparatus capable of suppressing contamination of a wafer container. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a plan view showing an example of a schematic configuration of a wafer container cleaning apparatus according to an embodiment. [Diagram 2] FIG. 2 is a diagram illustrating an example of the configuration of the cleaning tank 5 according to the embodiment. [Figure 3A] FIG. 3A is a view for explaining an example of a position of a third cleaning liquid supply unit when the shell is carried out, carried in, and dried according to the embodiment. [Figure 3B] FIG. 3B is a view for explaining an example of a position of a third cleaning liquid supply unit during cleaning of the shell according to the embodiment. [Figure 4] FIG. 4 is a diagram illustrating an example of the configuration of the control unit according to the first embodiment. [Diagram 5] FIG. 5 is a flow chart showing the flow of the self-cleaning process in the cleaning tank 5 executed by the wafer container cleaning apparatus according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, with reference to the attached drawings, an embodiment of the wafer storage container cleaning apparatus disclosed in the present application will be described in detail. Note that the wafer storage container cleaning apparatus disclosed in the present application is not limited to the following embodiment. Also, each embodiment and each modified example can be appropriately combined within a range where no contradiction occurs. Note that in the following embodiment, the wafer storage container to be cleaned is described as a FOUP, but the wafer storage container to be cleaned is not limited to this. For example, the wafer storage container to be cleaned may be a FOSB.

[0012] (Embodiment) 1 is a plan view showing an example of a schematic configuration of a wafer container cleaning apparatus 1 according to an embodiment. The wafer container cleaning apparatus 1 is installed, for example, in a factory that manufactures semiconductor wafers, and cleans wafer containers. As shown in FIG. 1, the wafer 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, an unload port 7, and a control unit 8.

[0013] The robot 3, the disassembly / connection stage 4, the cleaning tank 5, the vacuum tank 6 and the control unit 8 are provided inside the casing 1a of the wafer container cleaning apparatus 1. On the other hand, the load port 2 and the unload port 7 are provided across both the inside and the outside of the casing 1a of the wafer container cleaning apparatus 1.

[0014] The load port 2 carries the FOUP 20 to be cleaned, which is placed on the outside of the casing 1a of the load port 2, into the inside of the casing 1a. The FOUP 20 includes a shell (FOUP body) 20a and a door (lid) 20b. The shell 20a has an opening (shell opening) and a storage space for storing semiconductor wafers. The storage space is located inside the shell opening and communicates with the shell opening. The door 20b can be disassembled and connected to the shell 20a, and when connected to the shell 20a, the door 20b is attached in a state in which it can be opened and closed relative to the shell opening. In addition, the shell 20a is provided with a flange 20c. The flange 20c is a portion that is grasped (held) when the FOUP 20 is transported by an OHT (Overhead Hoist Transport), a robot 3, or the like.

[0015] For example, the FOUP 20, which is transported with the flange 20c being gripped by the OHT, is placed on the outside of the casing 1a of the load port 2. For example, as shown in FIG. 1, the FOUP 20 is placed so that the door 20b of the FOUP 20 faces the shutter 2a provided at the opening 1b of the casing 1a. When the FOUP 20 is placed on the load port 2 in this manner, the shutter 2a rises. This allows the FOUP 20 to be carried into the inside of the casing 1a from the opening 1b. That is, the FOUP 20 is allowed to be carried into the inside of the wafer container cleaning device 1. Then, the FOUP 20 is slid in the direction of the arrow 2b by the slide device of the load port 2. This allows the FOUP 20 to be carried into the inside of the casing 1a. Sliding by the slide device will be described. For example, a pin provided on the slide device is inserted into a hole provided on the bottom (mounting surface) of the FOUP 20, and the mounting surface of the FOUP 20 is fixed to the slide device. In this state, the slide device is slid in the direction of the arrow 2b, causing the FOUP 20 to slide 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 thus carried into the casing 1a, the shutter 2a descends, closing the opening 1b of the casing 1a. The slide device descends together with the pin to a position lower than the bottom end of the shutter 2a (the surface on which the FOUP 20 is placed) and returns to its original position outside the casing 1a.

[0016] The robot 3 transports the FOUP 20 to each section 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 transports the FOUP 20 to each section by extending and retracting the robot arm 3a and rotating it while the robot hand 3b grips the flange 20c.

[0017] The disassembly / connection stage 4 disassembles the FOUP 20 into a shell 20a and a door 20b, and connects the shell 20a and the door 20b. A latch key 4a is provided on the disassembly / connection stage 4. The latch key 4a is inserted into a key hole formed in the door 20b of the FOUP 20 and rotates, whereby the FOUP 20 is disassembled (separated) into the shell 20a and the door 20b, and the shell 20a and the door 20b are connected. For example, the FOUP 20 carried into the casing 1a is transported by the robot 3 to the disassembly / connection stage 4. In this case, the disassembly / connection stage 4 disassembles the FOUP 20 into the shell 20a and the door 20b. Note that disassembly can be rephrased as unlocking, and connection can be rephrased as locking.

[0018] The cleaning tank 5 is a tank for cleaning the FOUP 20. The cleaning tank 5 is an example of a cleaning unit. FIG. 2 is a diagram illustrating an example of the configuration of the cleaning tank 5 according to the embodiment. As illustrated in FIG. 2, for example, the cleaning tank 5 includes a cleaning tank body 5a, a lid portion 5b, a placement portion 5c, a first cleaning liquid supply portion (first cleaning liquid discharge portion) 5d, a second cleaning liquid supply portion (second cleaning liquid discharge portion) 5e, a drying portion 5f, a first discharge portion 5g, a second discharge portion 5h, a third cleaning liquid supply portion (third cleaning liquid discharge portion) 5p, a fixing portion 5s, and a hollow portion 5t.

[0019] The cleaning tank body 5a is a container capable of accommodating the FOUP 20 therein. The cleaning tank body 5a has an opening (main body opening) at the top and a cleaning space communicating with the main body opening. The cleaning space is a space present inside the main body opening. The shell 20a is carried into the cleaning space through the main body opening by the robot 3. In this manner, the shell 20a is carried into the inside of the cleaning tank body 5a. The carried shell 20a is then placed on the placement part 5c provided in the cleaning space of the cleaning tank body 5a. The placement part 5c is provided inside the cleaning tank body 5a, and is a platform (placement platform) on which the shell 20a can be placed with the shell opening of the shell 20a facing downward as shown in FIG. 2. The placement part 5c is provided with a positioning pin. The placement position of the shell 20a is determined by the positioning pin. As shown in FIG. 2, the placement part 5c is formed with a plurality of through holes 5c_1. The through hole 5c_1 communicates (connects) with the first discharge portion 5g. Also, an opening is provided at the center of the placement portion 5c.

[0020] The hollow portion 5t is connected to an opening provided at the center of the mounting portion 5c, and is configured to be rotatable around the fixed portion 5s with an axis 5l extending in the vertical direction as a rotation axis. When the hollow portion 5t rotates, the mounting portion 5c also rotates in conjunction with the rotation. The fixed portion 5s is a member fixed to the cleaning tank main body 5a. The fixed portion 5s is provided to penetrate the hollow portion 5t in the vertical direction, and supports the hollow portion 5t so that the hollow portion 5t can rotate. The fixed portion 5s includes a fixed base 5s_1 and a fixed shaft 5s_2.

[0021] The outer shape of the fixed base 5s_1 is larger than the outer shape of the hollow portion 5t. In this way, the cleaning liquid that cleans the inside of the shell 20a and flows to the upper surface of the fixed base 5s_1 can be prevented from flowing into the hollow portion of the hollow portion 5t. In addition, in the self-cleaning process in the cleaning tank 5 described later, the cleaning liquid that cleans the first cleaning liquid supply unit 5d or the third cleaning liquid supply unit 5p and flows to the upper surface of the fixed base 5s_1 can be prevented from flowing into the hollow portion of the hollow portion 5t.

[0022] Also, a convex portion extending downward may be provided on the outer periphery of the fixed base 5s_1. In this case, it is preferable to provide the upper end of the hollow portion 5t at a position higher than the upper surface of the mounting portion 5c. In this way, a labyrinth structure can be formed between the convex portion of the fixed base 5s_1 and the upper end of the hollow portion 5t. As a result, it is possible to further prevent the cleaning water used to clean the inside of the shell 20a or the cleaning water used during the self-cleaning process from flowing into the hollow portion 5t. When the hollow portion 5t is connected to the lower surface of the mounting portion 5c, a convex portion may be provided around the opening of the mounting portion 5c so as to surround the opening. In that case, the outer shape of the fixed base 5s_1 may be larger than the outer shape of the convex portion.

[0023] Lid 5b is provided on the upper side (main body opening side) of cleaning tank main body 5a, and opens and closes with respect to the main body opening of cleaning tank main body 5a by the operation of an air cylinder. A holding part (holding mechanism) 5i capable of adsorbing and holding door 20b is provided on the inside of lid 5b.

[0024] In this embodiment, when cleaning of the FOUP 20 is performed in the cleaning tank 5, the robot 3 transports the shell 20a and the door 20b on the disassembly / connection stage 4 separately to the cleaning tank 5. For example, the robot 3 transports the shell 20a from the opening of the cleaning tank body 5a to the inside of the cleaning tank body 5a with the opening of the shell 20a facing downward. Then, as shown in FIG. 2, the shell 20a is placed on the placement part 5c with the opening of the shell 20a facing downward. In addition, the robot 3 transports the door 20b to the holding part 5i so that the outer surface of the door 20b is held by the holding part 5i of the lid part 5b. As a result, when the lid part 5b is closed, the inner surface (inner surface) of the door 20b faces downward as shown in FIG. 2.

[0025] In addition, a first cleaning liquid supply unit 5d, a second cleaning liquid supply unit 5e, and a third cleaning liquid supply unit 5p are provided in the cleaning space of the cleaning tank main body 5a. The first cleaning liquid supply unit 5d, the second cleaning liquid supply unit 5e, and the third cleaning liquid supply unit 5p are supplied with a cleaning liquid (e.g., pure water such as DI water (deionized water)) used in cleaning the shell 20a and the door 20b. The first cleaning liquid supply unit 5d supplies (discharges) the cleaning liquid to the storage space (inner surface of the shell 20a) of the shell 20a, thereby cleaning the inside of the storage space (inner surface of the shell 20a). The second cleaning liquid supply unit 5e supplies (discharges) the cleaning liquid to the outer side surface of the shell 20a, thereby cleaning the outer side surface of the shell 20a. In addition, the third cleaning liquid supply unit 5p cleans the outer upper surface of the shell 20a and the inner surface of the door 20b by supplying (discharging) cleaning liquid to the outer upper surface of the shell 20a and the inner surface of the door 20b held by the holding portion 5i of the lid portion 5b.

[0026] The first cleaning liquid supply unit 5d is provided at a position where it can supply the cleaning liquid to the storage space of the shell 20a placed on the placement unit 5c. For example, the first cleaning liquid supply unit 5d includes at least one rod-shaped pipe extending upward from the upper surface of the base 5s_1 in the fixed unit 5s, at least one rod-shaped pipe extending horizontally, and a plurality of nozzles 5m provided on each pipe. The nozzle 5m is, for example, a two-fluid nozzle. When the nozzle 5m is a two-fluid nozzle, the nozzle 5m mixes air (an example of gas) with the cleaning liquid, atomizes the cleaning liquid by the air flow, and supplies the atomized cleaning liquid to the storage space of the shell 20a. Note that such a nozzle 5m can supply the cleaning liquid to the storage space without mixing the air with the cleaning liquid. That is, the nozzle 5m can supply the non-atomized cleaning liquid to the storage space without atomizing the cleaning liquid. The air and cleaning liquid are supplied to the nozzle 5m through piping provided in the fixed shaft 5s_2 and connected to a rod-shaped pipe extending upward from the upper surface of the base 5s_1 of the fixed part 5s.

[0027] As shown in Fig. 2, the first cleaning liquid supply unit 5d has a nozzle 5m that discharges cleaning liquid horizontally and a nozzle 5m that discharges cleaning liquid upward. The nozzle 5m that discharges cleaning liquid horizontally cleans the inner side surface of the shell 20a. The nozzle 5m that discharges cleaning liquid upward cleans the inner upper surface of the shell 20a. That is, the first cleaning liquid supply unit 5d is provided inside the shell 20a in a shell placed state in which the shell 20a is placed by the placement unit 5c, and discharges cleaning liquid onto the inner surface of the shell 20a.

[0028] The second cleaning liquid supply unit 5e is provided at a position where it can supply cleaning liquid to the outer side surface of the shell 20a. For example, the second cleaning liquid supply unit 5e includes at least one rod-shaped pipe extending in the vertical direction and a plurality of nozzles 5o provided on the pipe. The nozzle 5o is, for example, a single-fluid nozzle. When the nozzle 5o is a single-fluid nozzle, the nozzle 5o supplies cleaning liquid to the outer side surface of the shell 20a. That is, the second cleaning liquid supply unit 5e is provided outside the shell 20a in the above-mentioned shell-mounted state, and ejects cleaning liquid onto the outer surface of the shell 20a.

[0029] In this embodiment, in a shell non-placed state in which the shell 20a is not placed by the placement unit 5c (the shell 20a is not present in the cleaning tank 5), the outlet of the nozzle 5m that ejects the cleaning liquid in the horizontal direction of the first cleaning liquid supply unit 5d faces the outlet of the nozzle 5o of the second cleaning liquid supply unit 5e. That is, in the shell non-placed state described above, the outlet of the first cleaning liquid supply unit 5d and the outlet of the second cleaning liquid supply unit 5e face each other so that the cleaning liquid can be ejected from one outlet to the other.

[0030] The third cleaning liquid supply unit 5p is provided at a position capable of supplying cleaning liquid to the outer upper surface of the shell 20a and the inner surface of the door 20b held by the holding portion 5i of the lid portion 5b. For example, the third cleaning liquid supply unit 5p includes at least one rod-shaped pipe that extends horizontally and is rotatable, and a plurality of nozzles 5r or nozzles 5n provided on the pipe. The nozzle 5n is, for example, a two-fluid nozzle similar to the nozzle 5m that is provided so as to discharge toward the inner surface of the door 20b. When the nozzle 5n is a two-fluid nozzle, the nozzle 5n supplies atomized cleaning liquid to the inner surface of the door 20b. Also, the nozzle 5r is, for example, a one-fluid nozzle. When the nozzle 5r is a one-fluid nozzle, the nozzle 5r supplies cleaning liquid to the outer upper surface of the shell 20a. In this way, when the door 20b is in the door holding state in which the shell is placed as described above and the door 20b is held by the holding portion 5i of the lid portion 5b, the third cleaning liquid supply portion 5p ejects cleaning liquid onto the upper surface of the outer surface of the shell 20a and onto the inner surface of the door 20b that faces the upper surface of the shell 20a.

[0031] FIG. 3A is a diagram for explaining an example of the position of the third cleaning liquid supply unit 5p when the shell 20a according to the embodiment is taken out, taken in, and dried. FIG. 3B is a diagram for explaining an example of the position of the third cleaning liquid supply unit 5p when the shell 20a according to the embodiment is washed. In FIG. 3A, the drying unit 5f shows the position when the shell 20a according to the embodiment is taken out and taken in. For example, the nozzle 5r of the third cleaning liquid supply unit 5p arranged between the shell 20a and the door 20b in FIG. 2 is retracted to a position (retracted position) that does not interfere with the shell 20a when the shell 20a is taken out, taken in, and dried, as shown in FIG. 3A. Then, after the shell 20a is carried into the cleaning space and the lid 5b is closed with the door 20b held by the holder 5i, the nozzle 5r of the third cleaning liquid supply unit 5p rotates and moves to a position (cleaning position) above the shell 20a placed on the placement unit 5c and below the door 20b held by the holder 5i, as shown in FIG. 3B. When cleaning is completed, the nozzle 5r of the third cleaning liquid supply unit 5p rotates and returns to the retreated position. Although the nozzle 5n is not shown in FIGS. 3A and 3B, it moves in the same manner as the nozzle 5r.

[0032] In this embodiment, in the above-mentioned shell unplaced state and in the door unheld state in which the door 20b is not held by the holder 5i, when the nozzle 5r of the third cleaning liquid supply unit 5p is located at the cleaning position, the outlet of the nozzle 5r faces the outlet of the nozzle 5m that discharges the cleaning liquid upward. That is, in the above-mentioned shell unplaced state and in the above-mentioned door unheld state, the outlet of the first cleaning liquid supply unit 5d and the outlet of the third cleaning liquid supply unit 5p face each other so that the cleaning liquid can be discharged from one outlet to the other.

[0033] The drying section 5f is provided at a position where it can supply hot air (hot blow) to the inner surface of the shell 20a, the outer surface of the shell 20a, and the inner surface of the door 20b. For example, the drying section 5f includes at least two rod-shaped pipes extending in the vertical direction, at least two rod-shaped pipes extending in the horizontal direction, and a plurality of hot blow nozzles provided on each pipe. In this embodiment, at least one pipe extending upward from the upper surface of the base 5s_1 in the fixing section 5s and at least one pipe connected to the upper surface of the base 5s_1 in the fixing section 5s and extending in the horizontal direction are provided to supply hot air to the inner surface of the shell 20a when the shell 20a is placed. In addition, at least one pipe extending in the vertical direction and at least one pipe extending in the horizontal direction and rotatable are provided to supply hot air to the outer portion of the shell 20a. The hot blow nozzles provided on these pipes supply hot air to the inner surface of the shell 20a, the outer surface of the shell 20a, and the inner surface of the door 20b.

[0034] For example, in Fig. 2, the drying unit 5f disposed between the shell 20a and the door 20b is retracted to a position (retracted position) where it does not interfere with the shell 20a when the shell 20a is taken out, taken in, or washed. Then, when washing is completed, it rotates and moves to a position (drying position) above the shell 20a placed on the placement unit 5c and below the door 20b held by the holding unit 5i. When drying is completed, the drying unit 5f rotates and returns to the retracted position.

[0035] The cleaning tank body 5a also includes a first rotating unit including a motor 5k. The first rotating unit rotates the placement unit 5c by rotating the hollow portion 5t around an axis 5l extending in the vertical direction as a rotation axis during cleaning and drying of the shell 20a. The shell 20a placed on the placement unit 5c also rotates with the rotation of the placement unit 5c. The lid unit 5b also includes a second rotating unit including a motor 5j. The second rotating unit rotates the holding unit 5i around the axis 5l as a rotation axis during cleaning and drying of the door 20b. The door 20b held by the holding unit 5i also rotates with the rotation of the holding unit 5i. Thus, the cleaning liquid is evenly supplied to the FOUP 20 during cleaning of the FOUP 20. The hot blow is evenly supplied to the FOUP 20 during drying of the FOUP 20. Furthermore, liquid adhering to the shell 20a and the door 20b may be dried by rotation by the first rotating part and the second rotating part without supplying hot blow from the hot blow nozzle.

[0036] The first discharge part 5g discharges the cleaning liquid supplied (discharged) to the storage space of the shell 20a. As described above, the first discharge part 5g communicates (connects) with the through hole 5c_1. Therefore, the cleaning liquid supplied to the storage space of the shell 20a flows into the first discharge part 5g via the through hole 5c_1.

[0037] The second discharge section 5h discharges the cleaning liquid that has passed through the outside of the shell 20a. The cleaning liquid that has passed through the outside of the shell 20a is the cleaning liquid that has been supplied (discharged) to the outer surface of the shell 20a and the inner surface of the door 20b. For example, the second discharge section 5h is a discharge port provided at the bottom of the cleaning tank body 5a.

[0038] When cleaning of the FOUP 20 is completed in the cleaning tank 5, the robot 3 transports the shell 20a and the door 20b in the cleaning tank 5 to the vacuum tank 6 separately.

[0039] Returning to the explanation of Fig. 1, the vacuum chamber 6 is a chamber for vacuum-drying the FOUP 20. Inside the vacuum chamber 6, a holding unit for holding the shell 20a and door 20b transferred into the inside of the vacuum chamber 6, a halogen lamp, and a vacuum pump such as a dry pump or a mechanical booster pump capable of evacuating the inside of the vacuum chamber 6. With the shell 20a and door 20b held by the holding unit, the vacuum chamber 6 heats with the halogen lamp while evacuating the inside of the vacuum chamber 6 with the vacuum pump, thereby vacuum-drying the shell 20a and the door 20b.

[0040] When the vacuum drying of the FOUP 20 is completed in the vacuum chamber 6, the robot 3 transports the shell 20a and the door 20b separately from within the vacuum chamber 6 onto the disassembly / connection stage 4. Then, the disassembly / connection stage 4 connects the shell 20a and the door 20b together.

[0041] The unload port 7 carries out the cleaned and vacuum-dried FOUP 20 placed by the robot 3 in the portion of the unload port 7 inside the casing 1a to the outside of the casing 1a.

[0042] For example, the FOUP 20, whose shell 20a and door 20b are connected at the disassembly / connection stage 4 after vacuum drying, is transported and placed by the robot 3 in the inside of the casing 1a of the unload port 7. When the FOUP 20 is placed on the unload port 7 in this manner, the shutter 7a provided at the opening 1c of the casing 1a rises. This allows the FOUP 20 to be transported from the opening 1c to the outside of the casing 1a. That is, the FOUP 20 is transported to the outside of the wafer container cleaning apparatus 1. Then, the FOUP 20 is slid in the direction of the arrow 7b by the slide device of the unload port 7 (having the same mechanism as the slide device of the load port 2), and the FOUP 20 is transported to the outside of the casing 1a. When the FOUP 20 is transported to the outside of the casing 1a in this manner, the shutter 7a descends to close the opening 1c of the casing 1a.

[0043] The control unit 8 controls the overall operation of the wafer container cleaning apparatus 1. For example, the control unit 8 controls the load port 2, the robot 3, the disassembly / connection stage 4, the cleaning tank 5, the vacuum tank 6, and the unload port 7 to operate the load port 2, the robot 3, the disassembly / connection stage 4, the cleaning tank 5, the vacuum tank 6, and the unload port 7 as described above.

[0044] Fig. 4 is a diagram showing an example of the configuration of the control unit 8 according to the embodiment. As shown in Fig. 4, the control unit 8 includes a CPU (Central Processing Unit) 8a, a ROM (Read Only Memory) 8b, a RAM (Random Access Memory) 8c, a HDD (Hard Disk Drive) 8d, and a communication interface 8e. These are connected via an internal bus.

[0045] The CPU 8a executes various processes while using the storage area of ​​the RAM 8c as a temporary storage area for data used in the various processes. The processes executed by the CPU 8a will be described later. The ROM 8b and the HDD 8d store programs for executing the various processes, as well as various databases and tables used when executing the various processes. For example, the ROM 8b or the HDD 8d stores a program for executing a self-cleaning process in the cleaning tank 5.

[0046] The communication interface 8e is an interface for communicating with the above-mentioned components of the wafer container cleaning apparatus 1, and also for communicating with an external device connected via a network to the wafer container cleaning apparatus 1. For example, the communication interface 8e is a network interface card.

[0047] Next, the self-cleaning process in the cleaning tank 5 executed by the wafer container cleaning apparatus 1 according to the present embodiment will be described. FIG. 5 is a flow chart showing the flow of the self-cleaning process in the cleaning tank 5 executed by the wafer container cleaning apparatus 1 according to the embodiment. The self-cleaning process shown in FIG. 5 is executed when a user inputs an instruction to execute the self-cleaning process to the control unit 8 via an input interface such as a mouse, keyboard, or touch panel provided in the control unit 8 during a period in which maintenance of the wafer container cleaning apparatus 1 is performed. Note that the self-cleaning process is executed in a state in which the shell 20a and the door 20b have been removed from the cleaning tank 5 and the shell 20a and the door 20b are not present in the cleaning tank 5.

[0048] 5, the CPU 8a of the control unit 8 moves the nozzle 5r of the third cleaning liquid supply unit 5p to the cleaning position (step S101). As a result, the outlet of the nozzle 5r faces the outlet of the nozzle 5m that ejects the cleaning liquid upward.

[0049] Next, the CPU 8a controls the first cleaning liquid supply unit 5d to start cleaning the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p with the first cleaning liquid supply unit 5d (step S102). As a result, the nozzle 5m of the first cleaning liquid supply unit 5d that ejects cleaning liquid in the horizontal direction starts cleaning the second cleaning liquid supply unit 5e. Also, the nozzle 5m of the first cleaning liquid supply unit 5d that ejects cleaning liquid in the upward direction starts cleaning the third cleaning liquid supply unit 5p.

[0050] In step S102, the CPU 8a controls the first cleaning liquid supply unit 5d so that the flow rate of the cleaning liquid discharged from the nozzle 5m when cleaning the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p is greater than the flow rate of the cleaning liquid discharged from the nozzle 5m when cleaning the shell 20a. The reason for this will be described. For example, when cleaning the shell 20a, it is sufficient that the cleaning liquid discharged from the nozzle 5m reaches the inner surface of the shell 20a. On the other hand, when cleaning the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p, the cleaning liquid discharged from the nozzle 5m needs to reach the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p, which are farther away than the shell 20a. For this reason, the flow rate is increased so that the cleaning liquid discharged from the nozzle 5m reaches the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p.

[0051] Next, the CPU 8a judges whether or not a first cleaning time has elapsed since the first cleaning liquid supply unit 5d started cleaning the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p in step S102 (step S103). The first cleaning time is a predetermined time determined by experiment or simulation for which the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p can be expected to be sufficiently cleaned.

[0052] If the first cleaning time has not elapsed since the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p were started to be cleaned (step S103: No), the CPU 8a performs the judgment of step S103 again. On the other hand, if the first cleaning time has elapsed since the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p were started to be cleaned (step S103: Yes), the CPU 8a controls the first cleaning liquid supply unit 5d to end the cleaning of the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p (step S104). That is, the CPU 8a controls the first cleaning liquid supply unit 5d to stop the discharge of the cleaning liquid from the nozzle 5m of the first cleaning liquid supply unit 5d. In this way, the first cleaning liquid supply unit 5d cleans the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p for the first cleaning time.

[0053] Next, the CPU 8a controls the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p to start cleaning the first cleaning liquid supply unit 5d with the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p (step S105). As a result, the nozzle 5o of the second cleaning liquid supply unit 5e starts cleaning a portion of the first cleaning liquid supply unit 5d that includes the nozzle 5m that ejects the cleaning liquid in the horizontal direction. Also, the nozzle 5r of the third cleaning liquid supply unit 5p starts cleaning a portion of the first cleaning liquid supply unit 5d that includes the nozzle 5m that ejects the cleaning liquid in the upward direction.

[0054] In step S105, the CPU 8a controls the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p so that the flow rate of the cleaning liquid discharged from the nozzles 5o, 5r when cleaning the first cleaning liquid supply unit 5d is greater than the flow rate of the cleaning liquid discharged from the nozzles 5o, 5r when cleaning the shell 20a. The reason for this is the same as the reason why the flow rate of the cleaning liquid discharged from the nozzle 5m when cleaning the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p is greater than the flow rate of the cleaning liquid discharged from the nozzle 5m when cleaning the shell 20a.

[0055] Next, the CPU 8a judges whether or not a second cleaning time has elapsed since the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p started cleaning the first cleaning liquid supply unit 5d in step S105 (step S106). The second cleaning time is a predetermined time that is expected to sufficiently clean the first cleaning liquid supply unit 5d through experiments or simulations.

[0056] If the second cleaning time has not elapsed since the first cleaning liquid supply unit 5d was started to be cleaned (step S106: No), the CPU 8a performs the judgment of step S106 again. On the other hand, if the second cleaning time has elapsed since the first cleaning liquid supply unit 5d was started to be cleaned (step S106: Yes), the CPU 8a controls the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p to end the cleaning of the first cleaning liquid supply unit 5d (step S107). That is, the CPU 8a controls the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p to stop the discharge of the cleaning liquid from the nozzle 5o of the second cleaning liquid supply unit 5e and the nozzle 5r of the third cleaning liquid supply unit 5p. In this way, the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p clean the first cleaning liquid supply unit 5d for the second cleaning time.

[0057] Then, the CPU 8a moves the nozzle 5r of the third cleaning liquid supply unit 5p to the retracted position (step S108), and ends the self-cleaning process.

[0058] The wafer container cleaning apparatus 1 according to this embodiment has been described above. In this embodiment, the control unit 8 controls the second cleaning liquid supply unit 5e to discharge the cleaning liquid to the first cleaning liquid supply unit 5d in the above-mentioned shell unplaced state in step S105. More specifically, the control unit 8 controls the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p to discharge the cleaning liquid to the first cleaning liquid supply unit 5d in the above-mentioned shell unplaced state and the above-mentioned door unheld state in step S105. This makes it possible to remove contaminants attached to the first cleaning liquid supply unit 5d from the first cleaning liquid supply unit 5d. Therefore, it is possible to suppress contamination of the FOUP 20 to be cleaned in the cleaning tank 5 after the self-cleaning process.

[0059] In this embodiment, the control unit 8 controls the first cleaning liquid supply unit 5d to discharge the cleaning liquid to the second cleaning liquid supply unit 5e in step S102 before controlling the second cleaning liquid supply unit 5e to discharge the cleaning liquid to the first cleaning liquid supply unit 5d. More specifically, the control unit 8 controls the first cleaning liquid supply unit 5d to discharge the cleaning liquid to the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p in step S102 before controlling the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p to discharge the cleaning liquid to the first cleaning liquid supply unit 5d. As a result, even if the cleaning liquid containing contaminants drips from the third cleaning liquid supply unit 5p located above the first cleaning liquid supply unit 5d onto the first cleaning liquid supply unit 5d and causes contaminants to adhere to the first cleaning liquid supply unit 5d, the first cleaning liquid supply unit 5d is subsequently cleaned, thereby preventing the first cleaning liquid supply unit 5d from being contaminated. Also from this point of view, contamination of the FOUP 20 cleaned in the cleaning tank 5 after the self-cleaning process can be prevented.

[0060] In addition, when cleaning the inside of the shell 20a, contaminants may also adhere to the drying unit 5f connected to the fixed unit 5s. Therefore, in the self-cleaning process, the CPU 8a may oscillate the third cleaning liquid supply unit 5p to clean the hot blow nozzle of the drying unit 5f connected to the fixed unit 5s described above in addition to the first cleaning liquid supply unit 5d. This makes it possible to prevent contaminants adhering to the hot blow nozzle from adhering to the FOUP 20. As a result, it is possible to prevent contamination of the FOUP 20.

[0061] In addition, in the self-cleaning process, when the CPU 8a oscillates the third cleaning liquid supply unit 5p, the first cleaning liquid supply units 5d may be provided near the outer edge of the base 5s_1 of the fixed part 5s. That is, the first cleaning liquid supply units 5d may be provided at positions separated from each other. By oscillating the third cleaning liquid supply unit 5p, the first cleaning liquid supply units 5d are cleaned by the third cleaning liquid supply unit 5p even if the first cleaning liquid supply units 5d are provided at positions separated from each other. In addition, by providing the first cleaning liquid supply units 5d near the outer edge of the base 5s_1 of the fixed part 5s, the distance between the first cleaning liquid supply units 5d and the second cleaning liquid supply unit 5e is shortened. Therefore, the increase in the flow rate of the cleaning liquid discharged from the nozzle 5m or the nozzle 5o during the self-cleaning process can be suppressed.

[0062] The vicinity of the outer edge of the base 5s_1 of the fixed part 5s refers to a range from a position inside the outer edge of the hollow part 5t by a length equal to the diameter of the rod-shaped pipe constituting the first cleaning liquid supply unit 5d to the outer edge of the base 5s_1 of the fixed part 5s. The rod-shaped pipe constituting the first cleaning liquid supply unit 5d may be shaped to extend not only upward but also horizontally. For example, even if the rod-shaped pipe constituting the first cleaning liquid supply unit 5d is not in the vicinity of the outer edge of the base 5s_1 of the fixed part 5s and the nozzle 5m is in the vicinity of the outer edge of the base 5s_1 of the fixed part 5s, this is also included in providing the multiple first cleaning liquid supply units 5d in the vicinity of the outer edge of the base 5s_1 of the fixed part 5s.

[0063] In addition, not only the first cleaning liquid supply unit 5d facing the second cleaning liquid supply unit 5e, but also the first cleaning liquid supply unit 5d facing the drying unit 5f supplying hot air to the outer side surface of the shell 20a may be provided on the fixing unit 5s. In this case, the drying unit 5f on the fixing unit 5s may be provided between the first cleaning liquid supply units 5d. In this way, the drying unit 5f supplying hot air to the outer side surface of the shell 20a can also be cleaned during the self-cleaning process.

[0064] A particle counter may be provided in a flow path through which the cleaning liquid flows as waste liquid after the first discharge part 5g. The particle counter measures the number of particles contained in a predetermined unit volume (e.g., 10 ml) of waste liquid at a predetermined time interval. Then, instead of the judgment in step S106, the CPU 8a may judge whether the number of particles is less than a threshold value each time the particle counter measures the number of particles contained in a predetermined unit volume of waste liquid. If the number of particles is not less than the threshold value, the CPU 8a again judges whether the number of particles is less than the threshold value. If the number of particles is less than the threshold value, the CPU 8a may proceed to step S107.

[0065] A case will be described in which the FOUPs 20 to be cleaned are successively carried into the wafer container cleaning apparatus 1. In this case, the CPU 8a compares the time (time) T1 at which vacuum drying starts in the vacuum tank 6 with the time T2 at which cleaning of the shell 20a and the door 20b ends in the cleaning tank 5, and if the time T3 (T1-T2) obtained by subtracting the time T2 from the time T1 is longer than the time T4 required for the self-cleaning process, the self-cleaning process may be automatically executed after the shell 20a and the door 20b are carried out of the cleaning tank 5. Note that the time T2 at which cleaning of the shell 20a and the door 20b ends in the cleaning tank 5 also includes the time at which the shell 20a and the door 20b are carried out of the cleaning tank 5.

[0066] As described above, when the self-cleaning process is automatically performed, the shell 20a and the door 20b carried out from the cleaning tank 5 are transported onto the disassembly / connection stage 4 and wait at the disassembly / connection stage 4 until the vacuum drying of another FOUP 20 in the vacuum tank 6 is completed. In this manner, the robot 3 can transport another FOUP 20 during the self-cleaning process. Note that although the robot 3 cannot be used to transport another FOUP 20, the door 20b carried out from the cleaning tank 5 may be transported onto the disassembly / connection stage 4 and the shell 20a carried out from the cleaning tank 5 may wait while being held by the robot 3. Alternatively, the shell 20a may be transported onto the disassembly / connection stage 4 and the door 20b may wait while being held by the robot 3.

[0067] The self-cleaning process may be executed by a user operating an input interface such as a mouse, a keyboard, or a touch panel to operate each component in the cleaning tank 5. In other words, the self-cleaning process may not be executed under the control of the control unit 8.

[0068] In step S102, the flow rate of the cleaning liquid discharged from the nozzle 5m may be the same as the flow rate of the cleaning liquid discharged from the nozzle 5m when cleaning the shell 20a. For example, the flow rate at which the cleaning liquid discharged from the nozzle 5m reaches the second cleaning liquid supply unit 5e and the third cleaning liquid supply unit 5p is calculated in advance. Then, the shell 20a may be cleaned at the calculated flow rate.

[0069] In step S105, the flow rate of the cleaning liquid discharged from the nozzles 5o, 5r when cleaning the first cleaning liquid supply unit 5d may be the same as the flow rate of the cleaning liquid discharged from the nozzles 5o, 5r when cleaning the shell 20a. For example, the flow rate at which the cleaning liquid discharged from the nozzles 5o, 5r reaches the first cleaning liquid supply unit 5d is calculated in advance. Then, the shell 20a may be washed at the calculated flow rate.

[0070] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0071] 1. Wafer container cleaning equipment 5. Cleaning tank 5a Cleaning tank body 5b Lid 5c Placement section 5d First cleaning liquid supply unit 5e Second cleaning liquid supply unit 5p Third cleaning solution supply unit

Claims

1. 1. A wafer container cleaning apparatus for cleaning a wafer container having a shell with a shell opening and a door attached to the shell opening, comprising: a cleaning tank body having an opening on an upper surface thereof and capable of housing the wafer storage container therein; a cover portion provided on the opening side of the cleaning tank body and configured to open and close the opening of the cleaning tank body; a placement portion provided inside the cleaning tank body, on which the shell can be placed with the shell opening facing downward; a first cleaning liquid discharger that is provided inside the shell in a shell placement state in which the shell is placed on the placement section and that discharges a cleaning liquid onto an inner surface of the shell; a second cleaning liquid discharger that is provided on the outside of the shell when the shell is placed and that discharges a cleaning liquid onto an outer surface of the shell; Equipped with a discharge port of the first cleaning liquid discharger and a discharge port of the second cleaning liquid discharger opposed to each other so that cleaning liquid can be discharged from one discharge port to the other discharge port.

2. Further comprising a control unit that controls the first cleaning liquid discharge unit and the second cleaning liquid discharge unit; 2. The wafer storage container cleaning apparatus of claim 1, wherein the control unit controls the second cleaning liquid discharge unit to discharge a cleaning liquid to the first cleaning liquid discharge unit in a shell non-placed state in which the shell is not placed on the placement unit.

3. A wafer storage container cleaning apparatus as described in claim 2, wherein the control unit controls the first cleaning liquid discharging unit to discharge cleaning liquid to the second cleaning liquid discharging unit before controlling the second cleaning liquid discharging unit to discharge cleaning liquid to the first cleaning liquid discharging unit.

4. The lid portion has a retention mechanism for retaining the door, a third cleaning liquid discharger that discharges a cleaning liquid onto an upper surface of an outer surface of the shell and onto an inner surface of the door facing the upper surface of the shell when the door is in a door holding state in which the shell is placed and the door is held by the holding mechanism, the discharge port of the first cleaning liquid discharger includes a discharge port that discharges the cleaning liquid onto an upper surface of an inner surface of the shell in the shell placed state, the third cleaning liquid discharger is rotatably provided between a cleaning position where the third cleaning liquid discharger discharges the cleaning liquid onto the upper surface of the shell and the inner surface of the door, and a retreated position where the third cleaning liquid discharger does not interfere with the shell when the shell is loaded into or unloaded from the cleaning tank body; 3. The wafer storage container cleaning apparatus according to claim 1, wherein the outlets of the first cleaning liquid discharge unit that discharges toward the upper surface and the outlets of the third cleaning liquid discharge unit are opposed to each other so that cleaning liquid can be discharged from one outlet to the other outlet when the wafer storage container is located at the cleaning position.

5. a control unit that controls the first cleaning liquid discharge unit, the second cleaning liquid discharge unit, and the third cleaning liquid discharge unit, 5. The wafer storage container cleaning apparatus of claim 4, wherein the control unit controls the second cleaning liquid discharging unit and the third cleaning liquid discharging unit to discharge cleaning liquid to the first cleaning liquid discharging unit when the shell is not placed in the door unheld state in which the door is not held by the holding mechanism.

6. 6. The wafer storage container cleaning apparatus of claim 5, wherein the control unit controls the first cleaning liquid discharging unit to discharge cleaning liquid to the second cleaning liquid discharging unit and the third cleaning liquid discharging unit before controlling the second cleaning liquid discharging unit and the third cleaning liquid discharging unit to discharge cleaning liquid to the first cleaning liquid discharging unit.

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