Transport device and wafer container cleaning device

Abstract

To enable processing to be efficiently performed.SOLUTION: A transport device includes a posture adjusting device including a transport robot for transporting a wafer container to a mounting table, a detector for detecting the posture of the wafer container transported by the transport robot, and a controller for adjusting the posture of the wafer container based on a detection result from the detector. The transport robot includes a gripping unit for gripping the wafer container, and transports the wafer container to the mounting table on which the wafer container is to be placed while gripping the wafer container with the gripping unit. The controller adjusts the posture of the gripping unit based on the detection result from the detector such that the mounting targe surface of the wafer container, which will be placed on the mounting surface of the mounting table, is parallel to the mounting surface before the wafer container is placed on the mounting surface.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] A wafer storage container such as a FOUP (Front Opening Unified Pod) is used when moving a wafer on which a semiconductor element is formed through various processing steps (for example, resist coating, exposure / development, etching (film formation), resist stripping, cleaning, etc.) between the processing steps. The FOUP is transported by a robot while the wafer is held inside the FOUP.

[0003] The FOUP includes a FOUP main body and a door, and a flange that is gripped by a robot is provided on the FOUP main body. When the robot hand of the robot holds the FOUP main body in a direction in which the opening of the FOUP main body (the side where the door of the FOUP is attached) faces downward via the flange, a part of the flange may bend, causing the FOUP main body to hang downward with the vicinity of the flange held by the robot hand as a fulcrum. In this case, when the robot grips the flange, the portion that becomes the lower end of the FOUP main body is inclined with respect to the horizontal plane. When the robot transports the FOUP main body in such an inclined state to place it on a substantially horizontal stage or the like, the portion that becomes the lower end of the FOUP main body does not match the positioning pins provided on the stage or the like, making it difficult to place the FOUP main body.

[0004] In the case as described above, the process needs to be interrupted to unload the FOUP, resulting in a problem of poor processing efficiency.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The present invention has been made to solve the above-described problems, and an object thereof is to provide a transfer device and a wafer storage container cleaning device capable of efficiently performing processing.

Means for Solving the Problems

[0007] In order to solve the above-described problems and achieve the object, a transfer device according to an aspect of the present invention includes a transfer robot that transfers a wafer storage container to a mounting table, a detection unit that detects the posture of the wafer storage container transferred by the transfer robot, and a control unit that adjusts the posture of the wafer storage container based on a detection result by the detection unit. The transfer robot includes a gripping unit that grips the wafer storage container, and transports the wafer storage container to the mounting table on which the wafer storage container is placed while gripping the wafer storage container with the gripping unit. The control unit adjusts the posture of the gripping unit based on the detection result by the detection unit so that a mounting target surface of the wafer storage container to be mounted on the mounting surface of the mounting table becomes parallel to the mounting surface before being mounted on the mounting surface.

[0008] Further, in order to solve the above-described problems and achieve the object, a wafer storage container cleaning device according to an aspect of the present invention includes the above-described transfer device and a cleaning tank having the mounting table and a cleaning nozzle that cleans the wafer storage container while the wafer storage container is placed on the mounting surface of the mounting table.

Effects of the Invention

[0009] According to an aspect of the present invention, it is possible to provide a transfer device and a wafer storage container cleaning device capable of efficiently performing processing.

Brief Description of the Drawings

[0010]

Figure 1

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Figure 13

DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, with reference to the accompanying drawings, embodiments of the transfer device and the wafer storage container cleaning device disclosed in the present application will be described in detail. Note that the transfer device and the wafer storage container cleaning device disclosed in the present application are not limited to the following embodiments. Also, each embodiment and each modification can be appropriately combined within a range where no contradiction occurs.

[0012] (First Embodiment) FIG. 1 is a plan view showing an example of the schematic configuration of a wafer storage container cleaning device 100 according to the first embodiment. FIG. 2 is a cross-sectional view taken along line X-X of FIG. 1. The wafer storage container cleaning device 100 is provided, for example, in a factory for manufacturing semiconductor wafers and cleans wafer storage containers. As shown in FIGS. 1 and 2, the wafer storage container cleaning device 100 includes a transfer robot 1, a disassembling / connecting stage 2, a cleaning tank 3, a vacuum treatment tank 7, a control unit 8, a first loading / unloading port 9a, a second loading / unloading port 9b, a third loading / unloading port 9c, an input interface 10, and a housing 6.

[0013] Also, as shown in FIG. 3, in the first embodiment, the transfer robot 1, the control unit 8, and the distance sensor 20 (to be described in detail later) constitute an attitude adjustment device 30. That is, the attitude adjustment device 30 is provided inside the wafer storage container cleaning device 100 and includes the transfer robot 1, the control unit 8, and the distance sensor 20 (detection unit). The attitude adjustment device 30 adjusts the attitude of the transfer robot 1. A device including the attitude adjustment device 30 is also called a transfer device. The processing executed by the attitude adjustment device 30 will be described later. Note that FIG. 3 is a diagram showing an example of the configuration of the attitude adjustment device 30 according to the first embodiment.

[0014] In this embodiment, the wafer storage container 200 is, for example, a FOUP, a FOSB, etc., and includes a container body (shell) 201 and a door (lid) 202. The container body 201 has a hexahedral outer shape. And the container body 201 has a rectangular opening on one surface. Also, the container body 201 has a storage space for storing semiconductor wafers. The storage space exists inside the opening and communicates with the opening. The door 202 can be disassembled / connected to the container body 201, and the door 202 is detachable from the opening of the container body 201. When the door 202 is attached to the opening of the container body 201, the end of the container body 201 forming the opening is configured to coincide with the surface of the door 202 attached to the container body 201. Further, a flange 203 is provided on the container body 201. For example, the container body 201 has a flange 203 on another surface orthogonal (intersecting) to the surface having the opening. The flange 203 is a portion that is gripped (held) when the wafer storage container 200 is transported by an OHT (Overhead Hoist Transport), a transfer robot 1, etc., and is formed in a rectangular plate shape.

[0015] The transfer robot 1, the disassembly / connection stage 2, the cleaning tank 3, the cover part 5, the vacuum processing tank 7, the control part 8, and the distance sensor 20 are provided inside the housing 6. On the other hand, the first loading / unloading port 9a, the second loading / unloading port 9b, and the third loading / unloading port 9c are provided straddling the inside and outside of the housing 6.

[0016] The first loading / unloading port 9a loads the wafer storage container 200 to be cleaned, which is placed on the external portion of the housing 6 at the first loading / unloading port 9a, into the housing 6.

[0017] For example, on the external portion of the housing 6 at the first loading / unloading port 9a, a wafer storage container 200 that has been transported with the flange 203 gripped by the OHT is placed. For example, as shown in FIG. 1, when the wafer storage container 200 is placed on the first loading / unloading port 9a, the door 202 of the wafer storage container 200 faces the housing 6. When the wafer storage container 200 is thus placed on the first loading / unloading port 9a, the shutter provided at the opening 6a of the housing 6 rises. As a result, the wafer storage container 200 can be carried into the housing 6 from the opening 6a. Then, the wafer storage container 200 is slid in the inward direction by the slide device of the first loading / unloading port 9a and carried into the housing 6.

[0018] Also, the first loading / unloading port 9a unloads the washed and vacuum-dried wafer storage container 200 placed by the transfer robot 1 on the internal portion of the housing 6 at the first loading / unloading port 9a to the outside of the housing 6.

[0019] For example, on the internal portion of the housing 6 at the first loading / unloading port 9a, after vacuum drying, the wafer storage container 200 in which the container body 201 and the door 202 are connected at the disassembling / connecting stage 2 is transported and placed by the transfer robot 1. When the wafer storage container 200 is thus placed on the first loading / unloading port 9a, the shutter provided at the opening 6a of the housing 6 rises. As a result, the wafer storage container 200 can be unloaded from the opening 6a to the outside of the housing 6. Then, the wafer storage container 200 is slid in the outward direction by the slide device of the first loading / unloading port 9a and unloaded to the outside of the housing 6.

[0020] Similar to the first loading / unloading port 9a, the second loading / unloading port 9b can load and unload the wafer storage container 200 through the opening 6b of the housing 6. Also, the third loading / unloading port 9c can be configured to load and unload the wafer storage container 200 in the same manner as the first loading / unloading port 9a through the opening 6c of the housing 6.

[0021] The transfer robot 1 is a vertically articulated robot, and transfers the wafer storage container 200 to each part while gripping the flange 203 of the wafer storage container 200. FIG. 4 is a schematic diagram showing an example of the configuration of the transfer robot 1 according to the first embodiment. As shown in FIGS. 2 and 4, the transfer robot 1 includes a robot arm 1a, a robot hand 1b, a base portion 1c, a moving device 1d, and a wrist portion 1e. The transfer robot 1 supports the robot arm 1a by the base portion 1c, and extends and contracts or rotates the robot arm 1a while the robot hand 1b provided at the tip of the robot arm 1a grips the flange 203, thereby transferring the wafer storage container 200 to each part.

[0022] The moving device 1d includes a servo motor (not shown) and a ball screw mechanism, and can move the base portion 1c in the vertical direction in FIG. 1. That is, the moving device 1d moves the robot arm 1a and the robot hand 1b by moving the base portion 1c.

[0023] As shown in the example of FIG. 4, the robot arm 1a of the transfer robot 1 includes a rotation support member 1a1, a first arm 1a2, and a second arm 1a3.

[0024] The swing support member 1a1 is supported at the upper part of the base part 1c at the lower end part of the swing support member 1a1 in a rotatable state around a shaft (vertical axis) 11 extending in the vertical direction. Further, the first arm 1a2 is connected to the upper end side part of the swing support member 1a1 at one end side part of the first arm 1a2 in a rotatable state around a shaft (horizontal axis) 12 extending in the horizontal direction. Further, the second arm 1a3 is connected to the other end side part of the first arm 1a2 at one end side part of the second arm 1a3 in a rotatable state around the horizontal axis 13. Further, the wrist part 1e is connected to the other end side part of the second arm 1a3 in a rotatable state around the horizontal axis 15. Further, a robot hand 1b is connected to the tip part of the wrist part 1e in a rotatable state around a shaft 14 orthogonal to the horizontal axis 15. With the configuration as described above, the transfer robot 1 can move the robot hand 1b to various positions.

[0025] In the disassembling / connecting stage 2, a disassembling process of disassembling the wafer storage container 200 into the container body 201 and the door 202, and a connecting process of connecting the container body 201 and the door 202 are performed. FIG. 5 is a plan view showing an example of the disassembling / connecting stage 2 according to the first embodiment. FIG. 6 is a cross-sectional view taken along the line Y - Y (side cross-sectional view) in FIG. 5. Note that FIG. 6 shows a state where the door 202 is placed on the placement surface 2a1 on which the wafer storage container 200 of the disassembling / connecting stage 2 is placed, and FIG. 5 shows a state where the door 202 is not placed on the placement surface 2a1 of the disassembling / connecting stage 2.

[0026] As shown in FIGS. 5 and 6, the disassembling / connecting stage 2 includes a substantially square mounting table 2a, a plurality (four) of positioning members 2b, and a plurality (two) of pins 2c. The four positioning members 2b are provided at the four corners of the substantially square mounting surface 2a1 of the mounting table 2a. The positioning member 2b is provided with a step so that when the door 202 attached to the container body 201 is placed on the mounting surface 2a1, the corners of the lower surface of the container body 201 coincide. That is, the positioning member 2b is provided at a position corresponding to the four corners of the mounting target surface 201a (see FIG. 9) on the mounting table 2a. Therefore, the positioning member 2b can position the container body 201 and also position the door 202 placed on the mounting surface 2a1.

[0027] Two hole portions 2a2 are formed at the center of the mounting table 2a. The latch key 2d provided on the mounting table 2a is inserted into the hole portion 2a2 and rotates while being inserted into the key hole 202a formed in the door 202, thereby executing the disassembly process and the connection process of the wafer storage container 200. That is, when the latch key 2d rotates while being inserted into the key hole 202a, the locking / unlocking between the door 202 and the container body 201 is performed. The size of the door 202 and the position of the latch key 2d are defined by SEMI (Semiconductor Equipment and Materials International standards). Therefore, the positions where the positioning member 2b and the hole portion 2a2 are provided are determined according to the size of the door 202 and the position of the latch key 2d.

[0028] The pin 2c is provided on the mounting surface 2a1 so as to coincide with the recess 202b provided in the door 202. Since the position of the recess 202b is defined by the SEMI standard, the pin 2c is provided at a position corresponding to the position of the recess 202b.

[0029] In the disassembling / connecting stage 2, the wafer storage container 200 carried into the interior of the housing 6 is conveyed by the transfer robot 1, and the disassembling process is executed in the disassembling / connecting stage 2. After the disassembling process is executed in the disassembling / connecting stage 2, the transfer robot 1 individually conveys the container body 201 and the door 202 to the cleaning tank 3. Further, when the temporary drying of the wafer storage container 200 is completed in the cleaning tank 3, the transfer robot 1 individually unloads the container body 201 and the door 202 from the cleaning tank 3, and individually conveys the container body 201 and the door 202 to the vacuum processing tank 7. Further, the transfer robot 1 conveys the vacuum-dried container body 201 and door 202 to the disassembling / connecting stage 2, and in the disassembling / connecting stage 2, the connecting process is executed.

[0030] In the wafer storage container cleaning apparatus 100 according to the present embodiment, the disassembling / connecting stage 2 is provided on a plate-shaped support member disposed at a position higher than the installation surfaces of the cleaning tank 3, the vacuum processing tank 7, etc. within the housing 6.

[0031] The cleaning tank 3 is a tank for cleaning the wafer storage container 200. For example, in the cleaning tank 3, the container body 201 and the door 202 are separately transported by the transfer robot 1. Then, the cleaning tank 3 performs a cleaning process on the wafer storage container 200 while separately holding the container body 201 and the door 202. For example, as shown in FIG. 2, the cleaning tank 3 includes a cleaning tank body 3a having an opening on the upper surface, an upper lid 3b capable of opening and closing the opening of the cleaning tank body 3a, and an upper lid opening / closing drive mechanism 3c for opening and closing the upper lid 3b. In the cleaning tank 3, the upper lid 3b holds the door 202, and the container body 201 is placed on a rotating table provided in the cleaning tank body 3a. Then, in the cleaning tank 3, while rotating the container body 201 and the door 202 by a rotating mechanism (not shown), the cleaning tank 3 discharges a cleaning liquid (for example, pure water) from the cleaning nozzles it has to each of the container body 201 and the door 202, thereby cleaning the wafer storage container 200. That is, the cleaning tank 3 has a rotating table which is a mounting table, and has cleaning nozzles for cleaning the wafer storage container 200 in a state where the wafer storage container 200 is placed on the mounting surface of the rotating table. In the interior of the cleaning tank 3, for example, considering the dischargeability of the cleaning liquid, the opening of the container body 201 is arranged downward.

[0032] When the cleaning of the wafer storage container 200 is completed in the cleaning tank 3, subsequently, the cleaning tank 3 rotates the container body 201 and the door 202 in the cleaning tank 3, and blows dry air onto the container body 201 and the door 202 to perform drying. The drying in the cleaning tank 3 here is a process (preliminary drying) for generally drying the cleaning liquid adhering to the wafer storage container 200. When the preliminary drying of the wafer storage container 200 is completed in the cleaning tank 3, the transfer robot 1 separately transports the container body 201 and the door 202 in the cleaning tank 3 to the vacuum processing tank 7.

[0033] As shown in FIG. 1, the wafer storage container cleaning apparatus 100 has four cleaning tanks 3.

[0034] FIG. 7 is a plan view showing an example of the rotary table (mounting table) 3a1 provided in the cleaning tank 3 according to the first embodiment. FIG. 8 is a view showing a part of the side surface of the rotary table 3a1 according to the first embodiment. Note that FIG. 7 shows a state in which the container body 201 is not placed on the placement surface 3a21 on which the container body of the rotary table 3a1 is placed, and FIG. 8 shows a state in which the container body 201 is placed on the placement surface 3a21 of the rotary table 3a1.

[0035] As shown in FIGS. 7 and 8, the rotary table 3a1 includes a substantially square table 3a2 and a plurality (eight) of positioning members (positioning pins) 3a3. Two positioning members 3a3 are provided at each of the four corners of the substantially square placement surface 3a21 of the table 3a2. That is, the rotary table 3a1 is provided with positioning members 3a3 at positions corresponding to the four corners of the placement target surface 201a. Specifically, a convex-shaped frame 3a22 is provided on the placement surface 3a21, and the positioning members 3a3 are provided so as to match the convex shape of the frame 3a22. The positioning member 3a3 is a so-called positioning pin in the shape of a pin. The edge portion of the container body 201 is placed on the horizontally extending plate-like portion 3a31 of the positioning member 3a3. In this way, the positioning member 3a3 can position the container body 201 placed on the placement surface 3a21. Note that, as described above, the container body 201 is placed on the placement surface 3a21 of the rotary table 3a1 of the cleaning tank 3 so that the opening of the container body 201 faces downward.

[0036] Returning to FIG. 1, the vacuum processing tank 7 is a tank for vacuum-drying (main drying) the wafer storage container 200. For example, the vacuum processing tank 7 includes a vacuum tank body, an opening / closing lid, a heater, and a decompression device capable of evacuating the inside of the vacuum processing tank 7. In the vacuum processing tank 7, the container body 201 and the door 202 are carried into the inside of the vacuum tank body by the transfer robot 1, and while being evacuated by the decompression device and heated by the heater with the opening of the vacuum tank body closed by the opening / closing lid, the container body 201 and the door 202 are vacuum-dried.

[0037] The control unit 8 controls the operation of the entire wafer storage container cleaning apparatus 100. For example, the control unit 8 controls the transfer robot 1, the disassembling / connecting stage 2, the cleaning tank 3, the vacuum processing tank 7, the first loading / unloading port 9a, the second loading / unloading port 9b, and the third loading / unloading port 9c, so as to operate the transfer robot 1, the disassembling / connecting stage 2, the cleaning tank 3, the vacuum processing tank 7, the first loading / unloading port 9a, the second loading / unloading port 9b, the third loading / unloading port 9c, and the distance sensor 20 as described above.

[0038] For example, the control unit 8 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), and a communication interface. These are connected via an internal bus.

[0039] The CPU executes various processes while using the storage area of the RAM as a temporary storage area for data used in various processes. The ROM and the HDD store programs for executing various processes, various databases used when executing various processes, various tables, and the like.

[0040] The communication interface is an interface for communicating with the above-described respective parts of the wafer storage container cleaning apparatus 100 and for communicating with an external apparatus connected to the wafer storage container cleaning apparatus 100 via a network. For example, the communication interface is a network interface card.

[0041] The input interface 10 receives input operations of various instructions and various information from an operator. Specifically, the input interface 10 is connected to the control unit 8 and transmits the input operations received from the operator to the control unit 8. For example, the input interface 10 is a mouse, a keyboard, a touch panel, or the like.

[0042] As shown in FIGS. 5 and 6, in this embodiment, one distance sensor 20 is provided corresponding to one positioning member 2b. Specifically, the distance sensor 20 is provided at a portion where the step of the positioning member 2b is low (that is, the portion where the corner of the lower surface of the container body 201 is placed). The distance sensor 20 is provided inside the positioning member 2b so as to be able to detect the distance between an object located above the distance sensor 20 and the distance sensor 20. With such a configuration, the distance sensor 20 can detect the distance from the distance sensor 20 itself to the surface on the mounting table 2a side of the wafer storage container 200 being transported by the transfer robot 1 (the surface on the mounting table 2a side of the door 202 (the lower surface of the door 202)) or the surface on the mounting table 2a side of the container body 201 (the lower surface of the container body 201).

[0043] Here, in this embodiment, as described above, one distance sensor 20 is provided corresponding to one positioning member 2b. Therefore, the four distance sensors 20 detect the distances between the four corners of the lower surface of the wafer storage container 200 being transported by the transfer robot 1 or the four corners of the lower surface of the container body 201 and the distance sensors 20.

[0044] The robot hand 1b according to this embodiment includes a container body gripping portion 104 having a pair of gripping claws 104a1 and 104b1 for gripping the flange 203 of the container body 201, and a door gripping portion 105 having a pair of gripping claws for gripping the door 202 (see FIG. 9). The opening and closing directions of the gripping claws 104a1 and 104b1 of the container body gripping portion 104 and the opening and closing direction of the gripping claws of the door 202 are provided so as to be orthogonal to each other, and these opening and closing operations are performed by a drive portion (not shown).

[0045] Here, the sagging of the container body 201 (the deflection of the flange 203) described above will be described in more detail. FIG. 9 is a diagram showing an example of a state in which the robot hand 1b according to the first embodiment grips the flange 203 and lifts the container body 201. In the example of FIG. 9, a case is shown in which a pair of gripping claws 104a1 and 104b1 grip the flange 203 by sandwiching the flange 203 in the vertical direction (the vertical direction).

[0046] As shown in FIG. 9, when the robot hand 1b grips the flange 203 and lifts or moves the container body 201, a part of the flange 203 of the container body 201 may bend. In this case, the portion that becomes the lower end of the container body 201 (the lower surface where the mounting target surface 201a is formed and the opening of the container body 201 is formed) is inclined with respect to the horizontal plane. Originally, it is preferable that the flange 203 does not bend. FIG. 10 is a diagram showing an example of a state in which the robot hand 1b according to the first embodiment grips the flange 203 and does not lift the container body 201. As shown in FIG. 10, in the wafer storage container 200, when the robot hand 1b grips the flange 203 and the entire weight of the container body 201 does not act on the flange 203 without lifting the container body 201, the surface on which the flange 203 extends and the mounting target surface 201a are configured to be perpendicular to each other. Therefore, in a state where the flange 203 gripped by the robot hand 1b is not bent, the flange 203 gripped by the gripping claws 104a1 and 104b1 and the extending direction of the mounting target surface 201a are in a state of perpendicular intersection.

[0047] Here, the disadvantages that occur when the transfer robot 1 transfers the container body 201 to the rotating table 3a1 (see Fig. 7) of the cleaning tank 3 with the placement target surface 201a inclined with respect to the horizontal plane will be described. The transfer robot 1 will place the container body 201 on the placement surface 3a21 of the rotating table 3a1 with the placement target surface 201a inclined with respect to the horizontal plane. The placement surface 3a21 is designed to be a plane parallel to the horizontal plane, and the positioning member 3a3 is designed on the premise that the container body 201 is placed on the placement surface 3a21 with the placement target surface 201a parallel to the horizontal plane. For this reason, when the container body 201 is carried into the cleaning tank 3 with the placement target surface 201a inclined with respect to the horizontal plane, the container body 201 may ride on the positioning member 3a3, or the edge portion of the container body 201 may be arranged outside the positioning member 3a3, so that the container body 201 may not match the positioning member 3a3. In a state where the container body 201 does not match the positioning member 3a3, the container body 201 cannot be placed accurately on the placement surface 3a21 while being inclined, or the container body 201 may abut against the wall surface of the cleaning tank 3 during the transfer into the cleaning tank 3 and cannot be transferred, so it is necessary to take measures such as interrupting the process and unloading the wafer storage container 200, resulting in poor processing efficiency.

[0048] Next, the disadvantages that occur when the transfer robot 1 transfers the wafer storage container 200 to the mounting table 2a (see FIGS. 5 and 6) of the disassembling / connecting stage 2 with the lower surface of the door 202 of the wafer storage container 200 inclined with respect to the horizontal plane will be described. The transfer robot 1 will place the wafer storage container 200 on the placement surface 2a1 of the mounting table 2a with the lower surface of the door 202 inclined with respect to the horizontal plane. The placement surface 2a1 is designed to be a plane parallel to the horizontal plane, and the positioning member 2b and the pin 2c are designed on the premise that the wafer storage container 200 is placed on the placement surface 2a1 with the lower surface of the door 202 parallel to the horizontal plane. For this reason, when the placement target surface 201a is inclined with respect to the horizontal plane and is transferred to the disassembling / connecting stage 2, the door 202 may ride up on the positioning member 2b, and the door 202 may not match the positioning member 2b and the pin 2c. In such a case, it may not be possible to place the wafer storage container 200 on the placement surface 2a1, and the process may be interrupted and the wafer storage container 200 may be unloaded, resulting in poor processing efficiency.

[0049] Therefore, the wafer storage container cleaning device 100 having the posture adjustment device 30 according to the present embodiment adjusts the posture of the robot hand 1b of the transfer robot 1 (the posture of the container body 201 held by the robot hand 1b) so that the placement target surface 201a or the lower surface of the door 202 (an example of the placement target surface) is parallel to the horizontal plane, as will be described below.

[0050] The process performed by the posture adjustment device 30 is executed when the transfer robot 1 transfers the wafer storage container 200 from the loading / unloading port (the first loading / unloading port 9a, the second loading / unloading port 9b, the third loading / unloading port 9c) to the disassembling / connecting stage 2, and when the transfer robot 1 transfers the wafer storage container 200 from the disassembling / connecting stage 2 to the cleaning tank 3. Hereinafter, the process by the posture adjustment device 30 will be described by dividing it into two patterns.

[0051] (When transferring the wafer storage container from the loading / unloading port to the disassembling / connecting stage) First, the process executed when the transfer robot 1 transfers the wafer storage container 200 from the loading / unloading port to the disassembling / connecting stage 2 will be described.

[0052] First, the transfer robot 1 grips the flange 203 of the wafer storage container 200 placed in the housing 6 via the loading / unloading port with the robot hand 1b, and moves it toward a predetermined position above the disassembling / connecting stage 2. The transfer robot 1 stops the movement of the wafer storage container 200 at a position at a predetermined height above the placement surface 2a1 of the disassembling / connecting stage 2, and performs detection by the four distance sensors 20 in this state. The four distance sensors 20 detect the distances between the four corners of the placement target surface 201a of the wafer storage container 200 gripped by the transfer robot 1 and each distance sensor 20 (or reference point), and transmit detection signals indicating the detected distances to the control unit 8.

[0053] The control unit 8 receives four detection signals from the four distance sensors 20, and calculates the four distances indicated by the four detection signals. Then, the control unit 8 determines whether the four calculated distances are the same. Note that the control unit 8 may determine whether the four distances are substantially the same. Here, the control unit 8 determines that the four distances are substantially the same when the difference between the maximum value and the minimum value of the four distances is within a predetermined threshold, and determines that the four distances are not substantially the same when such difference is greater than the predetermined threshold. When the control unit 8 determines that the four distances are the same or substantially the same, it proceeds to the next process.

[0054] On the other hand, when it is determined that the four distances are not the same, or when it is determined that the four distances are not substantially the same, the control unit 8 adjusts the posture of the robot hand 1b so that the detection signals from the four distance sensors 20 are the same (including substantially the same with an allowable range). Specifically, for example, from the four distances detected by the distance sensor 20, among the four corners of the placement target surface 201a, a relatively low position (that is, a position where the distance to the distance sensor 20 is short; a position close to the distance sensor 20) is specified, and the specified relatively low position is moved upward to adjust the posture of the robot hand 1b so that the placement target surface 201a is parallel to the horizontal plane.

[0055] Note that the control unit 8 may specify a relatively high position (that is, a position where the distance to the distance sensor 20 is long; a position far from the distance sensor 20) among the four corners of the lower surface of the container body 201 from the four distances. Also, among the four distances detected by the distance sensor 20, not limited to the shortest distance and the longest distance, the posture of the robot hand 1b may be adjusted based on any one of the four detected distances. However, when the relatively high position is moved downward, the placement target surface 201a and the door 202 may come into contact with the disassembling / connecting stage 2. Therefore, considering this, it is desirable to determine the height position serving as a reference for posture adjustment from the four distances obtained by the distance sensor 20 so that the placement target surface 201a and the door 202 do not interfere with the disassembling / connecting stage 2.

[0056] Further, the control unit 8 calculates the angle formed by the placement target surface 201a when there is no deflection and the placement target surface 201a of the container body 201 actually lifted by gripping the flange 203g with the gripping claws 104a1 and 104b1 from the four distances, calculates the posture of the robot hand 1b when the lower surface of the door 202 (or the placement target surface 201a) is parallel to the horizontal plane from the calculated angle, and may control the robot hand 1b to be in the calculated posture.

[0057] After the posture of the robot hand 1b is adjusted, again, the four distance sensors 20 detect the distances between the four corners of the lower surface of the door 202 (or the placement target surface 201a) and each distance sensor 20, and transmit a detection signal indicating the detected distances to the control unit 8. The control unit 8 receives the four detection signals and calculates the four distances from the four received detection signals. Then, the control unit 8 determines again whether the four calculated distances are the same or substantially the same.

[0058] Until the control unit 8 determines that the four distances are the same or substantially the same, the distance sensors 20 and the control unit 8 repeatedly perform the detection of the four distances, the determination of whether the four distances are the same or substantially the same, and the adjustment of the posture of the robot hand 1b as described above.

[0059] Then, the transfer robot 1 transfers the wafer storage container 200 to the disassembly / connection stage 2 while the robot hand 1b maintains the finally adjusted posture, and ends the process. The robot hand 1b with the adjusted posture is in a state as shown in FIG. 11, for example. Note that FIG. 11 shows an example of the posture of the robot hand 1b adjusted so that the lower surface of the door 202 (or the placement target surface 201a) is parallel to the horizontal plane in the first embodiment.

[0060] In this way, the posture of the robot hand 1b is adjusted so that the placement target surface 201a and the lower surface of the door 202 are parallel to the horizontal plane, and the transfer robot 1 transfers the wafer storage container 200 to the disassembly / connection stage 2 while the robot hand 1b maintains the adjusted posture. Therefore, when the transfer robot 1 places the wafer storage container 200 on the placement surface 2a1 of the placement table 2a, the door 202 matches the positioning member 2b and the pin 2c. For this reason, the wafer storage container cleaning device 100 having the posture adjustment device 30 can continue the process without interrupting the process. Therefore, the wafer storage container cleaning device 100 having the posture adjustment device 30 according to the first embodiment can perform the process efficiently.

[0061] (When transporting the container body from the disassembling / connecting stage to the cleaning tank) Next, the process executed when the transfer robot 1 transports the container body 201 from the disassembling / connecting stage 2 to the cleaning tank 3 will be described.

[0062] Note that the posture adjustment device 30 may adopt the posture of the robot hand 1b adjusted when transporting the wafer storage container 200 from the loading / unloading port to the disassembling / connecting stage 2 as the posture of the robot hand 1b when transporting the container body 201 from the disassembling / connecting stage 2 to the cleaning tank 3. However, when being transported from the loading / unloading port to the disassembling / connecting stage 2, the door 202 is attached to the container body 201, while the object to be transported from the disassembling / connecting stage 2 to the cleaning tank 3 is the container body 201 without the door 202 attached. As described above, at the disassembling / connecting stage 2, the container body 201 and the door 202 are unlocked, and the container body 201 and the door 202 are separately carried into the cleaning tank 3 for cleaning. Therefore, the container body 201 transported from the disassembling / connecting stage 2 to the cleaning tank 3 is in a state without the door 202 attached. Since it becomes lighter by the weight of the door 202 and the amount of deflection becomes smaller, the amount of deflection when transporting the wafer storage container 200 from the loading / unloading port to the disassembling / connecting stage 2 is different from the amount of deflection when transporting the container body 201 from the disassembling / connecting stage 2 to the cleaning tank 3. For this reason, when the transfer robot 1 transports the container body 201 from the disassembling / connecting stage 2 to the cleaning tank 3, it is preferable for the posture adjustment device 30 to execute the posture adjustment process of the robot hand 1b again.

[0063] First, the transfer robot 1 grips the flange 203 of the container body 201 placed on the mounting table 2a of the disassembling / connecting stage 2 with the robot hand 1b, and moves the container body 201 toward a predetermined position above the disassembling / connecting stage 2. The transfer robot 1 stops the movement of the container body 201 at a predetermined position above the disassembling / connecting stage 2. Then, the transfer robot 1, the control unit 8, and the distance sensor 20 perform the same processing on the container body 201 as the processing performed on the mounting target surface 201a and the door 202 of the container body 201 when the wafer storage container 200 is transferred from the loading / unloading port to the disassembling / connecting stage 2. As a result, the posture adjusting device 30 adjusts the posture of the robot hand 1b so that the mounting target surface 201a is parallel to the horizontal plane. Thereby, as shown in FIG. 11, the posture of the robot hand 1b is adjusted, and the mounting target surface 201a is parallel to the horizontal plane.

[0064] Then, while the robot hand 1b maintains the adjusted posture, the transfer robot 1 transfers the container body 201 to the cleaning tank 3 and ends the process. Note that the door 202 removed from the container body 201 on the mounting table 2a of the disassembling / connecting stage 2 is subsequently transferred to the cleaning tank 3 by the transfer robot 1 after the container body 201 is transferred to the cleaning tank 3 by the transfer robot 1 and is attached to a predetermined position in the cleaning tank 3.

[0065] In this way, the posture of the robot hand 1b is adjusted so that the mounting target surface 201a is parallel to the horizontal plane, and while the robot hand 1b maintains the adjusted posture, the transfer robot 1 transfers the container body 201 to the cleaning tank 3. Therefore, when the transfer robot 1 places the container body 201 on the mounting surface 3a21 of the table 3a2, the container body 201 matches the positioning member 3a3. For this reason, the wafer storage container cleaning device 100 having the posture adjusting device 30 can continue the process without interrupting the process. Therefore, the wafer storage container cleaning device 100 having the posture adjusting device 30 according to the first embodiment can perform the process efficiently.

[0066] The wafer storage container cleaning apparatus 100 having the posture adjustment device 30 according to the first embodiment has been described above. As described above, the transfer robot 1 includes a robot hand 1b (more specifically, a container body gripping portion 104) that grips the wafer storage container 200, and in a state where the wafer storage container 200 is gripped by the robot hand 1b, the wafer storage container 200 is placed on a mounting table 2a having a mounting surface 2a1 on which the wafer storage container 200 is placed and having a positioning member for positioning the wafer storage container 200 in a state of being placed on the mounting surface 2a1. Further, the transfer robot 1 includes a robot hand 1b that grips the container body 201, and in a state where the container body 201 is gripped by the robot hand 1b, the container body 201 is placed on a rotating table 3a1 having a mounting surface 3a21 on which the container body 201 is placed and having a positioning member 3a3 for positioning the container body 201 in a state of being placed on the mounting surface 3a21. The distance sensor 20 detects the state (posture) of the wafer storage container 200 or the container body 201 conveyed by the transfer robot 1. Based on the detection result by the distance sensor 20, the control unit 8 adjusts the posture of the robot hand 1b so that the mounting target surface (the lower surface of the door 202) of the wafer storage container 200 that is to be mounted on the mounting surface 2a1 of the mounting table 2a becomes parallel to the mounting surface 2a1 before being mounted on the mounting surface 2a1. Further, based on the detection result by the distance sensor 20, the control unit 8 adjusts the posture of the robot hand 1b so that the mounting target surface 201a (the lower surface of the container body 201) of the container body 201 that is to be mounted on the mounting surface 3a21 of the rotating table 3a1 becomes parallel to the mounting surface 3a21 before being mounted on the mounting surface 3a21. Then, the control unit 8 controls the transfer robot 1 to transfer the wafer storage container 200 to the mounting table 2a in a state where the posture of the robot hand 1b is adjusted so that the lower surface of the door 202 is parallel to the mounting surface 2a1 of the mounting table 2a. Further, the control unit 8 controls the transfer robot 1 to transfer the container body 201 to the rotating table 3a1 in a state where the posture of the robot hand 1b is adjusted so that the mounting target surface 201a is parallel to the mounting surface 3a21 of the rotating table 3a1. Therefore, according to the first embodiment, as described above, the processing can be performed efficiently.

[0067] Also, according to the first embodiment, regardless of the types and individual differences of the wafer storage container 200 and the container body 201, the posture of the robot hand 1b can be accurately adjusted so that the lower surface of the door 202 is parallel to the placement surface 2a1, or the posture of the robot hand 1b can be adjusted so that the placement target surface 201a is parallel to the placement surface 3a21.

[0068] Also, in the first embodiment, it was exemplified that the four distance sensors 20 detect four distances and thereby adjust the posture of the wafer storage container 200. However, among the four provided distance sensors 20, based on the distances detected by at least two distance sensors 20 along the short side direction of the mounting table 2a, the posture of the container body 201 (robot hand 1b) may be adjusted. That is, the distance sensors 20 may be provided at two locations among the four positioning members 2b, at least at the positioning member 2b on the side gripped by the robot hand 1b and the positioning member 2b on the side opposite to the side gripped by the robot hand 1b. The inclination of the container body 201 is due to the deflection of the flange 203, and an inclination occurs in which the side opposite to the flange 203 side (the side away from the flange 203) is lowered with respect to the flange 203 side gripped by the robot hand 1b. There is almost no inclination in the direction orthogonal to this inclination, so there is no need to consider it in adjusting the posture of the container body 201. Then, the control unit 8 may adjust the posture of the robot hand 1b based on the inclination obtained from the distances detected by two of the four distance sensors 20. That is, the two distance sensors 20 may detect different two height positions along the direction from the side of the wafer storage container 200 gripped by the robot hand 1b to the side opposite to the side gripped by the robot hand 1b on the placement target surface 201a. And the control unit 8 may adjust the posture of the robot hand 1b based on the height positions detected by the two distance sensors 20. Therefore, according to the first embodiment, the posture of the robot hand 1b can be adjusted from the detection results of the two distance sensors 20.

[0069] (Second Embodiment) Next, a wafer storage container cleaning apparatus 100 having an attitude adjustment device 30 according to the second embodiment will be described. In the first embodiment, the case where the wafer storage container cleaning apparatus 100 having the attitude adjustment device 30 detects various distances described above using the distance sensor 20 and performs various processes using the detected distances was described. On the other hand, the wafer storage container cleaning apparatus 100 having the attitude adjustment device 30 according to the second embodiment includes a light transmitting / receiving type ON / OFF sensor (an example of a detection unit) instead of the distance sensor 20, and executes various processes using the ON / OFF sensor. Hereinafter, in the description of the second embodiment, the description of the configuration similar to that of the first embodiment may be omitted.

[0070] FIGS. 12 and 13 are diagrams showing an example of the arrangement of the light transmitting / receiving type ON / OFF sensors 300 and 310 according to the second embodiment. FIG. 12 is a plan view of the ON / OFF sensors 300 and 310 and the disassembling / connecting stage 2 according to the second embodiment. FIG. 13 is a side view of the container body 201 gripped and lifted by the robot hand 1b according to the second embodiment, the ON / OFF sensors 300 and 310, and the disassembling / connecting stage 2. As shown in FIGS. 12 and 13, when an object exists at a position at a height T above the mounting surface 2a1 of the mounting table 2a, the output signal of the light receiving sensor 302 (described later) is switched by the interruption of light reception, and in response to the output of this signal, the control unit 8 detects the presence or absence of an object at the position at the height T. The position at the height T is a position separated from the mounting surface 2a1 by a distance L upward.

[0071] Specifically, the ON / OFF sensor 300 includes a light-emitting sensor (light-emitting unit) 301 and a light-receiving sensor (light-receiving unit) 302. The light-emitting sensor 301 and the light-receiving sensor 302 are provided at a predetermined distance from each other. For example, as shown in FIG. 12, in a plan view, the light-emitting sensor 301 and the light-receiving sensor 302 are provided with the mounting table 2a interposed therebetween. The light-emitting sensor 301 emits light (projects light) toward the light-receiving sensor 302, and the light-receiving sensor 302 receives the light from the light-emitting sensor 301. When no object exists between the light-emitting sensor 301 and the light-receiving sensor 302, the light-receiving sensor 302 receives the light from the light-emitting sensor 301. When the light-receiving sensor 302 receives light, it outputs a detection signal (OFF signal) indicating that no object exists between the light-emitting sensor 301 and the light-receiving sensor 302 to the control unit 8. On the other hand, when the light-receiving sensor 302 does not receive the light from the light-emitting sensor 301, it outputs a detection signal (ON signal) indicating that an object exists between the light-emitting sensor 301 and the light-receiving sensor 302 to the control unit 8.

[0072] As shown in FIG. 12, in a plan view, the optical axis of the light-emitting sensor 301 is arranged to be parallel to the long side of the mounting table 2a and pass over the positioning member 2b on the side of the robot hand 1b (the side where the flange 203 is provided when the container body 201 is placed on the placement surface 2a1) (the side where the robot hand 1b is inserted). That is, the ON / OFF sensor 300 has the optical axis of the light-emitting sensor 301 in a direction orthogonal to the direction from the side of the wafer storage container 200 gripped by the robot hand 1b toward the side opposite to the side gripped by the robot hand 1b. With such a configuration, the ON / OFF sensor 300 can detect whether the lower end portion (the end portion on the placement surface 2a1 side of the surface of the container body 201 on the robot hand 1b side) 201b of the surface of the container body 201 gripped by the robot hand 1b exists at the position of the height T. The lower end portion 201b is an example of the first end portion.

[0073] The ON / OFF sensor 310 includes a light projecting sensor 311 and a light receiving sensor 312. The light projecting sensor 311 has the same configuration as the light projecting sensor 301, and the light receiving sensor 312 has the same configuration as the light receiving sensor 302.

[0074] As shown in FIG. 12, in a plan view, the light projecting sensor 311 is arranged such that its optical axis is parallel to the long side of the mounting table 2a and passes over the positioning member 2b on the side opposite to the robot hand 1b side. With such a configuration, the ON / OFF sensor 310 can detect whether or not the lower end portion (the end portion on the mounting surface 2a1 side of the surface on the side opposite to the robot hand 1b side of the container body 201) 201c of the surface on the side opposite to the robot hand 1b side of the container body 201 gripped by the robot hand 1b exists at the position of height T. The lower end portion 201c is an example of the second end portion.

[0075] Also, the plurality of ON / OFF sensors 300 and 310 are provided so as to be arranged along the direction from the side gripped by the robot hand 1b toward the side opposite to the side gripped by the robot hand 1b.

[0076] (When transporting the wafer storage container from the loading / unloading port to the disassembling / connecting stage) Next, in the second embodiment, the process executed when the transfer robot 1 transports the wafer storage container 200 from the loading / unloading port to the disassembling / connecting stage 2 will be described.

[0077] First, the transfer robot 1 moves the wafer storage container 200 placed in the housing 6 via the loading / unloading port while gripping the flange 203 of the wafer storage container 200 with the robot hand 1b toward a predetermined position above the disassembling / connecting stage 2. Then, the transfer robot 1 lowers the wafer storage container 200 from the predetermined position above the disassembling / connecting stage 2 toward the disassembling / connecting stage 2 located below the wafer storage container 200 at a predetermined speed.

[0078] Here, when the flange 203 is bent, the container body 201 hangs with the portion of the flange 203 gripped by the robot hand 1b as a fulcrum. Therefore, the portion of the container body 201 on the side opposite to the robot hand 1b side is located at a lower position than the portion of the container body 201 on the robot hand 1b side.

[0079] Therefore, the ON / OFF sensor 310 detects that the container body 201 reaches the position of height T earlier than the ON / OFF sensor 300. Specifically, the ON / OFF sensor 310 detects that the lower end portion of the surface of the container body 201 on the side opposite to the robot hand 1b side reaches the position of height T, and outputs a detection signal (ON signal) indicating the detection result to the control unit 8 at the timing when the output state of the ON / OFF sensor 310 changes from OFF to ON. Here, since the lowering of the door 202 continues, next, the ON / OFF sensor 300 detects that the container body 201 reaches the position of height T. Specifically, the ON / OFF sensor 300 detects that the lower end portion of the surface of the container body 201 on the robot hand 1b side reaches the position of height T, and outputs a detection signal (ON signal) indicating the detection result to the control unit 8 at the timing when the output state of the ON / OFF sensor 300 changes from OFF to ON.

[0080] When the control unit 8 receives an ON signal from the ON / OFF sensor 300, the control unit 8 controls the transfer robot 1 to stop the lowering of the wafer storage container 200 by the transfer robot 1. Thereby, at the timing when the ON / OFF sensor 300 detects the container body 201, the lowering of the wafer storage container 200 by the transfer robot 1 is stopped.

[0081] Then, the control unit 8 calculates the inclination angle of the placement target surface 201a with respect to the horizontal plane based on the time required from receiving the ON signal from the ON / OFF sensor 310 until receiving the ON signal from the ON / OFF sensor 300, the descending speed of the wafer storage container 200, and the distance between the ON / OFF sensor 300 and the ON / OFF sensor 310 (the distance between the light projecting sensors 301 and 311, the distance between the light receiving sensors 302 and 312). Then, the control unit 8 adjusts the posture of the robot hand 1b based on the calculated inclination angle so that the placement target surface 201a is parallel to the horizontal plane. In other words, the control unit 8 adjusts the posture of the robot hand 1b so that the placement target surface 201a is parallel to the placement surface 2a1.

[0082] Here, when adjusting the posture of the robot hand 1b, the control unit 8 may lower and adjust the relatively higher part of the container body 201, or may raise and adjust the relatively lower part. For example, when the ON / OFF sensor 310 side turns ON first (detects the container body 201), the control unit 8 can continue to lower the container body 201 until the ON / OFF sensor 300 turns ON and detect the inclination. However, if the control unit 8 continues to lower the container body 201 until the ON / OFF sensor 300 turns ON, depending on the degree of inclination of the container body 201, the container body 201 may collide with the mounting table 2a during the descent. Therefore, it is preferable that the control unit 8 stops the descent of the container body 201 when the ON / OFF sensor 310 side turns ON first, and raises and adjusts the relatively lower part of the container body 201. Alternatively, it is preferable that the control unit 8 stops the descent of the container body 201 when the ON / OFF sensor 310 side turns ON first, and adjusts so that only the ON / OFF sensor 300 side is lowered until the ON / OFF sensor 300 turns ON.

[0083] That is, the transfer robot 1 adjusts the posture of the robot hand 1b at a predetermined position above the disassembly / connection stage 2, which is higher than the position of height T. Then, with the posture of the robot hand 1b adjusted, the transfer robot 1 descends the wafer storage container 200 from the predetermined position above the disassembly / connection stage 2 toward the disassembly / connection stage 2 at a predetermined speed.

[0084] Alternatively, during the descent of the wafer storage container 200, the control unit 8 may repeatedly adjust the posture of the robot hand 1b while stopping the descent according to the output of the ON / OFF sensor, so as to adjust the gripping posture of the wafer storage container 200. That is, while the wafer storage container 200 is descending, the detection signal is transmitted to the control unit 8 at the timing when the ON / OFF sensor 300 detects the container body 201, and the detection signal is transmitted to the control unit 8 at the timing when the ON / OFF sensor 310 detects the container body 201. The control unit 8 controls the transfer robot 1 to stop the descent of the wafer storage container 200 by the transfer robot 1 at the timing when the two detection signals, that is, the detection signal from the ON / OFF sensor 300 and the detection signal from the ON / OFF sensor 310, are received.

[0085] Then, the control unit 8 determines whether or not the difference (time difference) between the timing of receiving the detection signal from the ON / OFF sensor 300 and the timing of receiving the detection signal from the ON / OFF sensor 310 is equal to or less than a predetermined threshold value. Here, when the time difference is equal to or less than the predetermined threshold value, it is considered that the placement target surface 201a is parallel to the placement surface 2a1. Also, when the time difference is greater than the predetermined threshold value, it is considered that the placement target surface 201a is not parallel to the placement surface 2a1.

[0086] When the time difference is equal to or less than a predetermined threshold, the control unit 8 causes the wafer storage container 200 to be conveyed to the mounting table 2a while maintaining the posture of the robot hand 1b. On the other hand, when the time difference is greater than the predetermined threshold, the posture adjustment device 30 calculates the inclination angle of the mounting target surface 201a with respect to the horizontal plane based on the time difference, the descending speed of the wafer storage container 200, and the distance between the ON / OFF sensor 300 and the ON / OFF sensor 310. Then, the control unit 8 readjusts the posture of the robot hand 1b based on the calculated inclination angle so that the mounting target surface 201a is parallel to the horizontal plane. Then, with the posture of the robot hand 1b adjusted, the transfer robot 1 raises the wafer storage container 200 again to a predetermined position above the disassembling / connecting stage 2. Then, with the posture of the robot hand 1b adjusted, the transfer robot 1 lowers the wafer storage container 200 again at a predetermined speed from a predetermined position above the disassembling / connecting stage 2 toward the disassembling / connecting stage 2. Then, the control unit 8 determines again whether or not the time difference between the timing at which the detection signal from the ON / OFF sensor 300 is received and the timing at which the detection signal from the ON / OFF sensor 310 is received is equal to or less than the predetermined threshold.

[0087] Until the control unit 8 determines that the time difference is equal to or less than the predetermined threshold, the posture adjustment device 30 repeatedly performs, as described above, calculation of the inclination angle, adjustment of the posture of the robot hand 1b, movement of the wafer storage container 200 to a predetermined position above the disassembling / connecting stage 2, lowering of the wafer storage container 200 at a predetermined speed, calculation of the time difference, and determination of whether or not the time difference is equal to or less than the predetermined threshold.

[0088] Finally, with the robot hand 1b maintaining the finally adjusted posture, the transfer robot 1 conveys the wafer storage container 200 to the disassembling / connecting stage 2 and ends the process.

[0089] In addition, in this embodiment, the case where the control unit 8 adjusts the posture of the robot hand 1b at the stop position of the descent of the wafer storage container 200 has been described. However, the transfer robot 1 may raise the wafer storage container 200 to a predetermined position above the disassembly / connection stage 2, and the control unit 8 may adjust the posture of the robot hand 1b at the predetermined position above the disassembly / connection stage 2.

[0090] (When transporting the container body from the disassembly / connection stage to the cleaning tank) Next, the process executed when the transfer robot 1 transports the container body 201 from the disassembly / connection stage 2 to the cleaning tank 3 will be described.

[0091] First, the transfer robot 1 raises the container body 201 above the disassembly / connection stage 2 at a predetermined speed with the robot hand 1b gripping the flange 203.

[0092] Here, when the flange 203 is bent, the placement target surface 201a of the container body 201 is inclined with respect to the horizontal plane. Therefore, the ON / OFF sensor 300 detects the absence of the container body 201 earlier than the ON / OFF sensor 310. Specifically, the ON / OFF sensor 300 detects that the lower end portion 201b of the surface of the container body 201 on the robot hand 1b side does not exist at the position of height T because the output state of the ON / OFF sensor 300 changes from ON to OFF for detecting the surface of the container body 201 on the robot hand 1b side, and outputs a detection signal (OFF signal) indicating the detection result to the control unit 8.

[0093] Here, since the ascent of the container body 201 continues, next, the ON / OFF sensor 310 detects that the container body 201 does not exist at the position of height T. Specifically, the ON / OFF sensor 310 detects the surface of the container body 201 on the side opposite to the robot hand 1b side. When the output state of the ON / OFF sensor 310 changes from ON to OFF, it detects that the lower end portion 201c of the surface of the container body 201 on the side opposite to the robot hand 1b side does not exist at the position of height T, and outputs a detection signal (OFF signal) indicating the detection result to the control unit 8.

[0094] When the control unit 8 receives the detection signal (OFF signal) from the ON / OFF sensor 310, it controls the transfer robot 1 to stop the ascent of the container body 201 by the transfer robot 1. Thereby, at the timing when the ON / OFF sensor 310 detects that the container body 201 does not exist, the ascent of the wafer storage container 200 by the transfer robot 1 is stopped.

[0095] Then, based on the time required from when the control unit 8 receives the detection signal from the ON / OFF sensor 300 until it receives the detection signal from the ON / OFF sensor 310, the predetermined speed of the ascent of the container body 201, and the distance between the ON / OFF sensor 300 and the ON / OFF sensor 310, the control unit 8 calculates the inclination angle of the placement target surface 201a with respect to the horizontal plane. Then, based on the calculated inclination angle, the control unit 8 adjusts the posture of the robot hand 1b so that the placement target surface 201a is parallel to the horizontal plane.

[0096] Here, when adjusting the posture of the robot hand 1b, the control unit 8 preferably raises and adjusts the relatively lower height portion of the placement target surface 201a, or only lowers and adjusts the higher portion, in the same manner as when transporting the wafer storage container 200 from the loading / unloading port to the disassembly / connection stage 2.

[0097] Then, while maintaining the posture of the robot hand 1b in the adjusted state, the transfer robot 1 lowers the container body 201 to a predetermined position lower than the position at height T. Then, while maintaining the posture of the robot hand 1b in the adjusted state, the transfer robot 1 raises the container body 201 from a predetermined position lower than the position at height T at a predetermined speed.

[0098] While the container body 201 is being raised, at the timing when the ON / OFF sensor 300 detects that the container body 201 has disappeared from the position at height T (that is, at the timing when the output state of the ON / OFF sensor 300 changes from ON to OFF), a detection signal (OFF signal) is transmitted to the control unit 8. Also, at the timing when the ON / OFF sensor 310 detects that the container body 201 has disappeared from the position at height T (that is, at the timing when the output state of the ON / OFF sensor 310 changes from ON to OFF), a detection signal is transmitted to the control unit 8 (OFF signal). The control unit 8 controls the transfer robot 1 to stop the raising of the wafer storage container 200 by the transfer robot 1 at the timing when it receives the two detection signals, the detection signal from the ON / OFF sensor 300 and the detection signal from the ON / OFF sensor 310.

[0099] Then, the control unit 8 determines whether or not the difference (time difference) between the timing of receiving the detection signal (OFF signal) from the ON / OFF sensor 300 and the timing of receiving the detection signal (OFF signal) from the ON / OFF sensor 310 is equal to or less than a predetermined threshold value. Here, when the time difference is equal to or less than the predetermined threshold value, it is considered that the placement target surface 201a is parallel to the horizontal plane. Also, when the time difference is greater than the predetermined threshold value, it is considered that the placement target surface 201a is not parallel to the horizontal plane.

[0100] When the time difference is equal to or less than a predetermined threshold, the control unit 8 causes the wafer storage container 200 to be conveyed to the cleaning tank 3 while maintaining the posture of the robot hand 1b. On the other hand, when the time difference is greater than the predetermined threshold, the posture adjustment device 30 recalculates the tilt angle of the placement target surface 201a with respect to the horizontal plane based on the time difference, a predetermined speed of ascent of the container body 201, and the distance between the ON / OFF sensor 300 and the ON / OFF sensor 310. Then, the control unit 8 readjusts the posture of the robot hand 1b based on the calculated tilt angle so that the placement target surface 201a is parallel to the horizontal plane. Then, the transfer robot 1 raises the container body 201 at a predetermined speed to a predetermined position above the disassembling / connecting stage 2 while maintaining the adjusted posture of the robot hand 1b, and lowers the wafer storage container 200 from the predetermined position above the disassembling / connecting stage 2 toward the disassembling / connecting stage 2 again at a predetermined speed. The control unit 8 determines again whether or not the time difference between the timing at which the detection signal (ON signal) from the ON / OFF sensor 300 is received and the timing at which the detection signal (ON signal) from the ON / OFF sensor 310 is received is equal to or less than the predetermined threshold.

[0101] Until it is determined by the control unit 8 that the time difference is equal to or less than the predetermined threshold, the posture adjustment device 30 repeatedly performs, as described above, calculation of the tilt angle, adjustment of the posture of the robot hand 1b, movement of the wafer storage container 200 to a predetermined position above the disassembling / connecting stage 2, lowering of the wafer storage container 200 at a predetermined speed, calculation of the time difference, and determination of whether or not the time difference is equal to or less than the predetermined threshold.

[0102] Finally, while the robot hand 1b maintains the finally adjusted posture, the transfer robot 1 conveys the wafer storage container 200 to the disassembling / connecting stage 2 and ends the process.

[0103] In the second embodiment, the ON / OFF sensors 300 and 310 are provided at a predetermined position that is a predetermined height T higher than the placement surface 2a1 of the placement table 2a. Then, at the height T of the predetermined position, the ON / OFF sensors 300 and 310 detect the presence or absence of the end portion (first end portion) on the placement surface 2a1 side of the surface on the robot hand 1b side of the wafer storage container 200 conveyed by the transfer robot 1, and the presence or absence of the end portion (second end portion) on the placement surface 2a1 side of the surface on the side opposite to the robot hand 1b side of the wafer storage container 200. Further, at the height T of the predetermined position, the ON / OFF sensors 300 and 310 detect the presence or absence of the end portion (first end portion) 201b on the placement surface 2a1 side of the surface on the robot hand 1b side of the container body 201 conveyed by the transfer robot 1, and the presence or absence of the end portion (second end portion) 201c on the placement surface 2a1 side of the surface on the side opposite to the robot hand 1b side of the container body 201. Then, the control unit 8 adjusts the posture of the robot hand 1b based on the presence or absence of the first end portion and the presence or absence of the second end portion.

[0104] The wafer storage container cleaning apparatus 100 having the posture adjustment device 30 according to the second embodiment can continue the process without interrupting the process, similar to the first embodiment. Therefore, the wafer storage container cleaning apparatus 100 having the posture adjustment device 30 according to the second embodiment can perform the process efficiently, similar to the first embodiment.

[0105] In the above embodiment, since the weight of the wafer storage container 200 changes depending on whether the door 202 is attached or not, it is exemplified that it is desirable to perform adjustment by the posture adjustment device 30 according to the inclined state due to deflection in both cases where the door 202 is attached and where it is not. However, the present invention is not limited to this. When the difference in the amount of deflection of the container body 201 due to the attachment or non-attachment of the door 202 is small and does not affect the placement on the placement surface, either the posture of the robot hand 1b in the state where the door 202 is attached or the posture of the robot hand 1b in the state where the door 202 is not attached may be applied to both of them.

[0106] In the above-described embodiment, it was exemplified that the placement surfaces (placement surfaces 2a1 and 3a21) are provided horizontally, and the posture of the robot hand 1b is adjusted so that the placement target surface 201a and the door 202 are held and conveyed in parallel with respect to this horizontal plane. However, the present invention is not limited to this. The placement surface is not limited to being provided parallel to the horizontal plane, and may be inclined. Further, the inclination of the placement target surface 201a and the door 202 adjusted by the posture adjustment device 30 includes those substantially parallel to the placement surface, and the posture adjustment device 30 can adjust the inclination of the placement target surface 201a and the door 202 changed by the deflection of the flange 203 within a range where it can be placed on the placement surface by adjusting the posture of the robot hand 1b.

[0107] In the above-described embodiment, it was exemplified that the distance sensor 20, the ON / OFF sensors 300 and 310 are provided on the disassembling / connecting stage 2. However, the present invention is not limited to this. A distance sensor (detection unit) capable of detecting the distance from a predetermined position of the robot hand 1b (for example, a position facing the edge of the opening of the container body 201) to the container body 201 is provided at a predetermined position of the robot hand 1b, and the posture adjustment device 30 may detect the sag of the container body 201 based on the distance acquired by the distance sensor and adjust the posture of the robot hand 1b. At this time, for example, it is conceivable that the position serving as the sag fulcrum varies depending on the type of the wafer storage container 200. Therefore, it is desirable to obtain an appropriate distance in advance through experiments.

[0108] In the above-described embodiment, the robot hand 1b was exemplified as the object to be adjusted by the posture adjustment device 30. However, the present invention is not limited to this. The posture adjustment device 30 may adjust the posture of the container body 201 gripped by the robot hand 1b by combining the position adjustments of any one of the robot arm 1a, the robot hand 1b, the moving device 1d, and the wrist portion 1e of the transfer robot 1, or a plurality of these members (all are examples of gripping portions).

[0109] In the above-described embodiment, an example was given in which the wafer storage container 200 is placed on the placement surface while maintaining the posture obtained as a result of the adjustment by the posture adjustment device 30 being performed a plurality of times. However, the present invention is not limited to this. The adjustment of the posture by the posture adjustment device 30 does not necessarily have to be performed over a plurality of times, and the posture may be adjusted by a single adjustment based on the detection result by the detection unit and then placed on the placement surface.

[0110] Also, in the above-described embodiment, an example was given in which the distance sensor 20 and the ON / OFF sensors 300 and 310 as the detection unit are provided on the side of the placement target surface 201a. However, the present invention is not limited to this. The detection unit may be provided on the surface side facing the placement target surface 201a, and the inclination of the placement target surface 201a may be indirectly obtained by the posture adjustment device 30 obtaining the inclination of the surface facing the placement target surface 201a. Such a configuration is also included as an example of the detection unit.

Explanation of Reference Numerals

[0111] 1 Transfer robot 1b Robot hand 2 Disassembly / connection stage 3 Cleaning tank 8 Control unit 100 Wafer storage container cleaning device 104 Container body gripping part

Claims

1. A transfer robot for transferring a wafer storage container to a mounting table, a detection unit for detecting the posture of the wafer storage container transferred by the transfer robot, a control unit for adjusting the posture of the wafer storage container based on the detection result by the detection unit, having a posture adjustment device, the transfer robot includes a gripping part for gripping the wafer storage container, and with the wafer storage container gripped by the gripping part, the wafer storage container is transferred to a mounting table on which the wafer storage container is to be placed, the control unit adjusts the posture of the gripping part based on the detection result by the detection unit so that the mounting target surface of the wafer storage container to be placed on the mounting surface of the mounting table is parallel to the mounting surface before being placed on the mounting surface, transfer device.

2. The control unit controls the transfer robot to transfer the wafer storage container to the mounting table in a state where the posture of the gripping part is adjusted so that the mounting target surface is parallel to the mounting surface of the mounting table. The transfer device according to claim 1.

3. The detection unit detects two different height positions along a direction from the side of the wafer storage container gripped by the gripping part to the side opposite to the side gripped by the gripping part on the mounting target surface, the control unit adjusts the posture of the gripping part based on the height detected by the detection unit, The transfer device according to claim 1.

4. Positioning members are provided on the mounting table at positions corresponding to the four corners of the mounting target surface, The detection unit is provided at at least two positions, one on the side gripped by the gripping part and the other on the side opposite to the side gripped by the gripping part, among the positioning members. The transfer device according to claim 3.

5. The detection unit is a light projecting and receiving sensor having a light projecting part and a light receiving part, and has an optical axis of the light projecting part in a direction orthogonal to the direction from the side of the wafer storage container gripped by the gripping part to the side opposite to the side gripped by the gripping part, and is provided so as to be arranged in a plurality along the direction from the side gripped by the gripping part to the side opposite to the side gripped by the gripping part, the control unit adjusts the posture of the gripping part based on the signal output from the detection unit, The transfer device according to claim 1.

6. The transfer device according to any one of claims 1 to 5, and A cleaning tank having the placement table and a cleaning nozzle for cleaning the wafer storage container in a state where the wafer storage container is placed on the placement surface of the placement table; A wafer storage container cleaning apparatus comprising the same.

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