JP2015050410A - Load port for detecting a plurality of kinds of semiconductor wafers - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a load port capable of mounting a different kind of wafer cassettes and capable of mapping a semiconductor wafer housed inside, with no special reforming.SOLUTION: A second wafer cassette can be mounted on a stage for mounting a first wafer cassette via a cassette adaptor. From the information of a detection switch which the cassette adaptor includes, a kind of a wafer cassette is identified. By operating a mapping sensor which matches with a kind of the cassette adaptor, mapping information of a semiconductor wafer is obtained.

Description

The present invention relates to a wafer cassette for storing semiconductor wafers, a load port for detecting presence / absence of various wafers housed therein by mounting wafer cassettes of different sizes each housing a plurality of wafers having different diameters, And a wafer mapping apparatus. Furthermore, the present invention relates to a cassette adapter for positioning and mounting a wafer cassette that is fixed on a load port and accommodates a semiconductor wafer having a relatively small diameter.

In a general semiconductor integrated circuit manufacturing process, an integrated circuit having a fine pattern is formed by repeatedly performing various processes such as exposure, film formation, etching, and heat treatment on a substrate such as a semiconductor wafer. These various processing steps are performed by a substrate processing apparatus including a processing chamber composed of dedicated equipment for each processing. Between each of these processes, the semiconductor wafer is placed horizontally on each shelf plate at a certain interval in the vertical direction on each shelf plate formed inside a dedicated wafer cassette corresponding to the diameter. And transported between the processes manually or by a transport device provided in the factory.

In recent years, various processing apparatuses have become expensive due to miniaturization of semiconductor circuit line width design rules, and as a result, improvement in yield in various processing steps has become a major issue. As a solution for improving the yield, the diameter of the wafer is increasing, and the diameter of the semiconductor wafer is increased from 150 mm to 200 mm and 300 mm. Recently, a semiconductor manufacturing process using a wafer having a diameter of 450 mm. Is becoming mainstream.

On the other hand, as the diameter of the semiconductor wafer increases, the price of the semiconductor wafer itself, which is the material for the semiconductor chip, has also increased. Therefore, when it is not necessary to mass-produce semiconductor chips, it is also necessary from the viewpoint of manufacturing cost to perform various processes using a semiconductor wafer having a relatively small diameter in a 300 mm or 450 mm apparatus. It has become. Also, from the viewpoint of effectively utilizing the conventional manufacturing equipment, a single production line can be formed by combining an existing processing apparatus for semiconductor wafers having a relatively small diameter and a processing apparatus for semiconductor wafers having a relatively large diameter. In many cases, apparatuses that can carry semiconductor wafers having relatively small diameters such as 150 mm and 200 mm into processing apparatuses for semiconductor wafers having relatively large diameters such as 300 mm and 450 mm have been devised by apparatus manufacturers. .

For example, in Patent Document 1, a carrier mounting table for mounting a first wafer cassette that accommodates a semiconductor wafer having a diameter of 300 mm, which is the first size, is detachably positioned on the carrier table, and the first A carrier mounting table including a plate-like member for mounting a second wafer cassette that accommodates a semiconductor wafer having a second size different from the size is disclosed. The plate-like member on which the second cassette is placed is provided with a movable positioning member so as to be compatible with various cassettes.

Further, in Patent Document 2, a mounting unit on which a sealed container that stores a relatively large-diameter semiconductor wafer is mounted, and a small-sized semiconductor wafer that is detachably mounted on the mounting unit. There is disclosed a mounting device including an adapter on which an open-type storage device is mounted. The hermetically sealed container described herein includes an openable and closable lid called FOUP (Front-Opening Unified Pod) that accommodates a 300 mm semiconductor wafer so that the internal air in which the semiconductor wafer is accommodated is kept airtight. It is the storage container comprised in this. An open-type container is called an open cassette, and is generally provided with a plurality of slots for supporting semiconductor wafers in the form of shelves at equal intervals, and the semiconductor wafers are opened to the surrounding atmosphere. It is to be stored.

In Patent Document 2, when the FOUP is mounted on the mounting table, the mounting table includes a pin that is pushed down by the FOUP and a sensor that detects the pressed pin. Further, when the open cassette is placed on the adapter, there is disclosed a method for detecting the presence of the open cassette by being provided with a mechanism for pushing down the pin provided on the placement table by being pushed by the open cassette. ing.
Japanese Patent Laid-Open No. 10-144755 JP 2003-142551 A

By using the apparatus disclosed in Patent Documents 1 and 2 above, it is possible to place a storage container storing semiconductor wafers having different diameters, and to transfer the semiconductor wafer stored inside to the processing apparatus. However, a new problem has occurred. In general, a mounting table on which a container called a FOUP or an open cassette that stores a specific type of semiconductor wafer is mounted, the presence / absence of each semiconductor wafer stored in the container and its mounting state When a container is placed, information on the presence / absence of a semiconductor wafer called mapping data and information on whether or not it is normally placed are automatically detected when the container is placed. Is done. Based on the detected mapping data, the transfer mechanism provided in the transfer apparatus automatically transfers the target semiconductor wafer to the processing apparatus.

The devices disclosed in Patent Documents 1 and 2 do not have a mechanism for automatically acquiring such mapping data, so when a container other than a predetermined container is placed via an adapter. The mapping data, the size of the semiconductor wafer, and the container type must be manually input to the control unit, which has been a major obstacle to automation. Further, when there is an input error, there has been a problem in that the finger of the transfer robot and the semiconductor wafer collide to damage the semiconductor wafer.

The present invention has been made in view of the above problems, and can mount a plurality of types of wafer cassettes. Further, the present invention automatically detects the mounting state of semiconductor wafers stored in each wafer cassette. An object is to provide a load port that can be used.

In order to solve the above problem, a load port according to a first aspect of the present invention includes a port opening, a door that covers the port opening, and a semiconductor wafer having a first diameter that is accommodated in a shelf shape. A stage for placing one wafer cassette at a predetermined position, and a second wafer cassette that is detachably installed on the stage and accommodates semiconductor wafers having a second diameter in a shelf shape are placed at the predetermined position. A cassette adapter to be mounted; a detection switch that is provided on the stage and detects that the first wafer cassette or the cassette adapter is mounted; and the cassette adapter is provided with the second wafer cassette including: A cassette identification unit for detecting that the wafer is placed; a first mapping sensor for detecting a semiconductor wafer having the first diameter; and the second diameter. A second mapping sensor for detecting a semiconductor wafer; a mapping sensor driving mechanism for moving the first and second mapping sensors forward and backward relative to the wafer cassette; and the first and second mapping sensors in the vertical direction An elevating mechanism that moves up and down, and a signal sent from the first mapping sensor when the first wafer cassette is placed, and a second mapping when the second wafer cassette is placed. And a control unit that receives a signal sent from the sensor.

With this configuration, the load port of the present invention has a cassette adapter installed on a stage having a structure in which a wafer cassette containing a semiconductor wafer having a diameter of 300 mm is placed, and a second diameter such as a diameter of 200 mm or 150 mm on the cassette adapter. The control unit automatically recognizes the size of the wafer cassette based on a signal from the cassette identification unit, and receives the signal from the mapping sensor corresponding to the wafer cassette. A mapping signal can be selectively acquired. As a result, it is possible to eliminate the troubles required for the conventional apparatus such as mapping sensor replacement work and manual wafer cassette data input by the operator.

According to a second aspect of the present invention, in the load port of the present invention, the first mapping sensor includes a first light projector and a first light receiver, the first light projector and the first light receiver. The separation distance is smaller than the horizontal dimension of the opening formed in the first wafer cassette and larger than the horizontal dimension of the opening formed in the second wafer cassette. The second mapping sensor has a second light projector and a second light receiver, and a distance between the second light projector and the second light receiver is determined by an opening formed in the first wafer cassette. It is smaller than the horizontal dimension and smaller than the horizontal dimension of the opening formed in the second wafer cassette.

With this configuration, when the second mapping sensor detects the semiconductor wafer having the second diameter housed in the second wafer cassette, the first mapping sensor collides with the second wafer cassette. Can be avoided.

According to a third aspect of the present invention, there is provided the load port according to the present invention, wherein the first light projector and the first light receiver, and the second light projector and the second light receiver are parallel to the door. The first light projector and the first light receiver are mounted in a pair on a swing frame swingable about a horizontal axis extending in the direction. It is characterized by being arranged closer to the wafer cassette placed on the stage than the projector and the second light receiver.

With this configuration, the second mapping sensor can be arranged in the same plane inside the first mapping sensor without blocking the optical axis of the first mapping sensor. Further, when the first mapping sensor detects the semiconductor wafer having the first diameter housed in the first wafer cassette, the second mapping sensor collides with the semiconductor wafer having the first diameter. You can avoid that.

According to a fourth aspect of the present invention, in the load port according to the present invention, the first optical axis irradiated from the first projector has the first diameter accommodated in the first wafer cassette. The second optical axis that is disposed at a predetermined angle with respect to the surface of the semiconductor wafer and is irradiated from the second projector has the second diameter accommodated in the second wafer cassette. The semiconductor wafer is arranged so as to have a predetermined angle with respect to the surface of the semiconductor wafer.

With this configuration, even when a semiconductor wafer whose optical axis is thinner than the respective width dimension is detected, the light is reliably shielded, and troubles due to erroneous detection can be prevented.

According to a fifth aspect of the present invention, in the load port of the present invention, the cassette adapter covers the periphery of the second wafer cassette, and the second diameter with respect to the second wafer cassette by a transfer means. It is characterized by comprising a protective cover in which an opening for carrying in and out a semiconductor wafer having the above is formed. With this configuration, it is possible to prevent the operator from inadvertently contacting the wafer cassette placed on the cassette adapter. Furthermore, when the wafer cassette is an open cassette, it is exposed to an environment where the apparatus cleanliness is lower than that inside the EFEM while the accommodated semiconductor wafer is being unloaded and loaded, but by providing this protective cover. The contamination of the semiconductor wafer due to the low clean environment can be suppressed.

The load port of the present invention according to claim 6 is characterized in that an area of the opening formed in the protective cover is substantially the same as an opening area of the port opening.

With this configuration, highly clean air that flows out from the inside of the EFEM through the load port opening can be taken into the protective cover through the opening of the protective cover. In particular, a slight gap is provided between the partition that forms the load port opening and the protective cover, and a slight gap is provided, so that this gap becomes a positive pressure air seal, and air with low cleanliness in the external environment Can be prevented.

The load port of the present invention according to claim 7 is characterized in that a part of the protective cover is provided with an openable / closable door for accessing the second wafer cassette. With this configuration, the operator can easily access the wafer cassette, and the inside of the protective cover can be maintained in a clean atmosphere.

The load port of the present invention according to claim 8 further includes storage means for storing position information relating to the first and second wafer cassettes taught in advance, and the control unit includes the first port. When the wafer cassette is placed, the positional information related to the first wafer cassette stored in the storage means is read, an operation command is transmitted to the mapping sensor driving mechanism and the lifting mechanism, and the second wafer cassette is read out. Is placed, the position information regarding the second wafer cassette stored in the storage means is read out, and an operation command is transmitted to the mapping sensor driving mechanism and the lifting mechanism.

With this configuration, the control unit automatically detects the type of the wafer cassette placed on the load port, and the mapping sensor driving mechanism and the lifting / lowering are performed in accordance with the operation data that matches the wafer cassette stored in the storage means. Since the operation command can be transmitted to the mechanism, the operator can perform automatic conveyance without transmitting the operation command.

According to a ninth aspect of the present invention, there is provided a transfer apparatus comprising the load port of the present invention, further holding and transferring the semiconductor wafer accommodated in the wafer cassette based on mapping information transmitted from the load port. It is characterized by having a transfer robot.

  With this configuration, the diameter of the semiconductor wafer detected by the load port, the mounting state in the wafer cassette, the presence / absence information of the semiconductor wafer on each shelf board is acquired by the transfer robot provided in the transfer device, and this information is obtained. Based on this, it is possible to automatically move to an appropriate transfer position that matches the wafer cassette, hold the semiconductor wafer, and transfer it to a target location.

The load port of the present invention automatically detects the type of the wafer cassette by placing the first and third wafer cassettes via the cassette adapter on the stage on which the first wafer cassette is placed, Since the mapping operation can be automatically performed by the mapping sensor corresponding to the wafer cassette, it is not necessary to perform a remodeling operation corresponding to a different wafer cassette required for the conventional load port.

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view showing an outline of a semiconductor manufacturing system 1 including a carrier mounting table 2 generally called a load port according to the present invention. In general, the semiconductor manufacturing system 1 includes a processing apparatus 4 that performs various processes on the surface of a semiconductor wafer 3 in a predetermined atmosphere, and a hermetic container 5 called FOUP from the previous process. It is composed of an EFEM (Equipment Front End Module) 6 which is a transfer device for transferring the semiconductor wafer 3 that has been transferred to the processing apparatus 4.

The EFEM 6 is a transfer device that delivers the semiconductor wafer 3 between the FOUP 5 and the processing apparatus 4. The EFEM 6 is placed on each shelf in the FOUP 5, the load port 2 that places the FOUP 5 and opens and closes the lid 18. The semiconductor wafer 3 held by the fingers 8 and transported to the processing apparatus 4 through a previously taught path, and the center alignment of the semiconductor wafer 3 and the notches and orientation flats formed on the semiconductor wafer 3. And an apparatus called an aligner 9 for positioning the semiconductor wafer 3 in the rotational direction.

In this explanatory diagram, the vertical direction is the Z-axis direction, the direction perpendicular to the Z direction, and the direction in which the plurality of load ports 2 are arranged in the EFEM 6 is the X-axis direction. The direction perpendicular to the direction and the X-axis direction is taken as the Y-axis direction.

The transfer robot 7 includes a finger 8 that holds the semiconductor wafer 3 and includes a transfer arm 9 that is configured to bend, extend, turn, and move up and down. Between the FOUP 5, the aligner 9, and the processing apparatus 4, The semiconductor wafer 3 can be transferred. The operation of each axis of the load port 2, aligner 9, transfer robot 7, etc. is controlled by a control device 11 disposed in the EFEM 6. The control device 11 stores the coordinate data, route data, and the like when the transfer robot 7 accesses in advance in a storage unit (not shown) provided inside, and in accordance with the stored operation sequence, the load port 2, the aligner 9, An appropriate operation command is issued to the transfer robot 7. Further, the EFEM 6 is provided with an input unit 12, and these coordinate data, route data, input of an operation command by an operator, and the like can be manually input via the input unit 12.

A space in which the transfer robot 7 operates is covered with a partition 13 composed of a frame and a cover on all sides, and an FFU (Fun Filter Unit) 14 is installed on the ceiling of the partition 13. The FFU 14 filters the air introduced from the outside by a fan and supplies it as a clean laminar flow as a downward laminar flow inside the EFEM 6. By the down flow of the clean air supplied from the FFU 14, Is maintained at a positive pressure with respect to the external environment, and a clean environment is always maintained.

Next, the load port 2 will be described below with reference to FIGS. FIG. 2 is a cross-sectional view of the periphery of the stage drive mechanism 16 of the load port 2 of the present embodiment as viewed from the positive direction of the X axis, and FIG. 3 is a perspective view showing the load port 2 of the present embodiment. In the semiconductor manufacturing process, the load port 2 mounts the FOUP 5 that accommodates the semiconductor wafer 3 therein, opens and closes the lid 18, and information on the presence / absence of the semiconductor wafer 3 on each shelf plate formed therein, And it is an apparatus which acquires the stock information regarding the semiconductor wafer 3, such as the information of whether it is mounted normally. The semiconductor wafer 3 is automatically transferred into the processing apparatus 4 by the transfer robot 7 provided in the EFEM 6 by acquiring the inventory information in the FOUP main body 30.

The load port 2 is fixed at a predetermined position of a partition 13 that forms an internal space of the EFEM 6, and a stage 15 that fixes the FOUP 5 at a predetermined position, and a stage drive mechanism that moves the stage 15 forward and backward in the Y-axis direction. 16, a port opening 17 for carrying the semiconductor wafer 3 accommodated in the FOUP 5 by the transfer robot 7, and a surface area substantially the same as the opening area of the port opening 17, XZ The door 19 integrated with the lid 18 for sealing the inside of the FOUP 5, the door lifting / lowering mechanism 20 for moving the door 19 up and down, and the load information of the semiconductor wafer 3 inside the FOUP 5 are arranged in the plane. It is comprised from the mapping apparatus 21 for acquiring.

The stage 15 accurately positions and fixes the FOUP 5 at a predetermined position, and supports the load in the vertical direction of the FOUP 5. On the surface of the stage 15, cylindrical positioning pins 22 called kinematic pins are erected at three places so as to draw an isosceles triangle in plan view. The positioning pin 22 has a substantially hemispherical shape at the top, and the top of the positioning pin 22 and a conical recess formed at a position corresponding to the positioning pin 22 at the bottom of the FOUP 5 come into contact with each other. The top portion of each positioning pin 22 is guided by the corresponding inclined surface of the conical recess so that the FOUP 5 can be accurately positioned with respect to the stage 15. The FOUP 5 placed on the stage 15 is structured to be locked on the positioning pin 22 by the locking hook 23, and thus on the stage 15. Further, in the load port 2 of this embodiment, three detection switches 31 for detecting whether or not the FOUP 5 is normally placed on the positioning pin 22 are arranged so as to protrude from the surface of the stage 15. Yes. The position of the detection switch 31 in the height direction is adjusted so that all the detection switches 31 are pressed by the bottom surface of the FOUP 5 when the FOUP 5 is normally placed.

The stage drive mechanism 16 includes a motor 24 as a drive source, a feed screw mechanism 25 in which a female screw is fixed to the stage 15, and a guide rail 26 that is arranged in parallel to the feed screw mechanism 25 and guides the stage 15. Is provided. The feed screw mechanism 25 and the guide rail 26 are fixed so as to be positioned parallel to each other on the frame 27 of the load port 2 so that the stage 15 can be moved back and forth in the Y-axis direction with respect to the door 19. . The rotation shaft of the motor 24 is connected to the feed screw mechanism 25, and the rotation of the motor 24 is transmitted to the feed screw 25, so that the stage 15 can be moved back and forth with respect to the door 19 to an arbitrary position. ing. Note that the stage 24 can be accurately moved to an arbitrary position by using a motor 24 that can control the rotation angle, such as a stepping motor or a servo motor.

The door 19 has a registration pin 28 for positioning with respect to the lid 18, a latch key 29 that interlocks with the latch key hole by being fitted in a latch key hole provided in the lid 18 and rotating, and a latch key 29 Is provided with a latch mechanism (not shown) that switches the lid 18 between a locked state and an unlocked state by rotating the. With this configuration, after the lid 18 and the door 19 abut, the latch key 29 is rotated by the latch mechanism, so that the locked state between the lid 18 and the FOUP main body 30 is released, and at the same time, the lid 18 and the door. 19 is integrated.

The door 19 is fixed to a bracket 32 that is substantially U-shaped when viewed from above, and is attached to the door elevating mechanism 20 via the bracket 32 so as to be movable up and down. The door 19 waiting at a position where it can be integrated with the lid 18 in the Z-axis direction is locked by the lid 18 after the lid 18 is brought into contact with the advance of the stage 15 by the stage drive mechanism 16. The mechanism is unlocked and integrated with the lid 18. Thereafter, the lid 18 and the FOUP main body 6a are separated, and the door 19 integrated with the lid 18 is moved downward in the Z-axis minus direction by the door lifting mechanism 20 to an arbitrary position. Referring to FIG. 3, the door elevating mechanism 20 is configured so that the elevating motor 33, which is a driving source, is rotated in the same direction by rotating the feed screw mechanism 34 installed so as to be parallel to the Z axis. The door 19 can be moved up and down in the Z-axis direction to an arbitrary position within a range guided by the guide rail 35 installed so as to be parallel to the guide rail 35. The lift motor 33 is a stepping motor, servo motor, or the like that can control the rotation angle by a pulse signal whose shaft momentum is proportional to the amount of drive pulses, so that the door 19 can be accurately moved up and down to an arbitrary position. It becomes possible to make it. In place of the lifting motor 33, a cylinder using fluid pressure such as air pressure or hydraulic pressure may be used. The control unit 72 receives the operation commands to the drive mechanisms described above and the input signals from the sensors and switches. Further, the control unit 72 includes a storage unit 79, and the storage unit 79 stores therein information and operation programs related to the load port 2, position information about each wafer cassette, and position information taught in advance as data. The storage means 79 included in the load port 2 of this embodiment includes a magnetic disk as a storage medium. However, in addition to the magnetic disk, it is sufficient to use a semiconductor element represented by an optical disk or a flash memory. Is possible.

Here, a wafer cassette for housing the semiconductor wafer 3 will be described. FIG. 4A shows an airtight container called FOUP 5 that accommodates semiconductor wafers 3a having relatively large diameters such as 300 mm and 450 mm on a shelf plate formed therein with a space in the vertical direction. Is a wafer cassette called an open cassette 43 that accommodates semiconductor wafers 3b having a relatively small diameter, such as 150 mm and 200 mm, on a shelf plate formed on the inner side thereof at intervals in the vertical direction. The FOUP 5 is formed of a FOUP main body 30 that places and accommodates the semiconductor wafer 3a on a shelf formed inside, and a lid 18 that is integrated with the door 19 by a latch mechanism and can be locked and unlocked. Therefore, the semiconductor wafer 3 accommodated therein can be stored in an airtight state, and the open cassette 43 accommodates the semiconductor wafer 3 accommodated in an open state with respect to the external atmosphere.

Both the FOUP body 30 and the open cassette 43 support the semiconductor wafers 3a and 3b in a horizontal state on a shelf plate formed at equal intervals in the vertical direction on the inside. The FOUP body 30 and the open cassette 43 can both accommodate 25 semiconductor wafers 3 having a predetermined diameter. Each of the accommodated semiconductor wafers 3 is stacked and accommodated at the same position in plan view. In addition, the dimensions of the FOUP 5 for the 300 mm semiconductor wafer 3a in the X direction and the Y direction are both about 1.5 times the size of the open cassette 43 for the 200 mm semiconductor wafer 3b. An interval in the vertical direction (Z direction) of the formed shelf boards is wider than an interval in the vertical direction (Z direction) of the shelf boards formed in the open cassette 43. As a result, when accommodating the same number of semiconductor wafers 3, the overall height of the FOUP 5 is larger than the overall height of the open cassette 43. Note that in the standard compiled by the Semiconductor Equipment and Materials International (SEMI) International Semiconductor Manufacturing Equipment Material Association, the vertical pitch of the shelf board supporting the semiconductor wafer 3 of each cassette is a cassette for a semiconductor wafer 3b having a diameter of up to 150 mm. Is approximately 7 mm for a semiconductor wafer 3 b cassette having a diameter of 200 mm, 10 mm for a cassette for semiconductor wafer 3 a having a diameter of 300 mm, and 12 mm for a cassette having a diameter of 450 mm.

Next, the mapping device 21 included in the load port 2 of the present embodiment will be described with reference to FIGS. 3, 5, and 6. FIG. 5 is a perspective view of the mapping device 21 of the present embodiment as viewed obliquely behind the load port 2, and FIG. 6 is a first mapping sensor 53a and a second mapping sensor 53b included in the mapping device 21 of the present embodiment. It is the top view which showed typically. The mapping device 21 determines whether or not the semiconductor wafer 3 is placed on the shelf plate in the wafer cassette placed on the load port 2 and whether or not the semiconductor wafer 3 is placed normally. This is a device for detecting the above. The mapping device 21 provided in the load port 2 of the present embodiment has a support shaft 38, and this support shaft 38 extends below the door 19 in the X-axis direction parallel to the door 19. With C as the central axis, it is rotatably attached to a bracket 32 supporting the door 19 via a bearing. At both ends of the support shaft 38, both ends of a swing frame 39 having a U-shape in front view and disposed in the vicinity of the door 19 so as to surround both side surfaces and the upper side surface of the door 19 are respectively provided. It is fixed. With the above-described configuration, the mapping device 21 can be moved up and down in the Z-axis direction together with the door 19 by the operation of the door lifting mechanism 20, and the swing frame 39 provided in the mapping device 21 has the mapping sensor drive mechanism 45. Thus, the periphery of the door 19 can be swung around the horizontal axis C parallel to the door 19 as a central axis. With this configuration, the first and second mapping sensors 53 a and 53 b can move forward and backward with respect to the FOUP 5 and the open cassette 43 that are placed and fixed on the stage 15. Further, since the bracket 32 has one end fixed to the door 19 and the other end fixed to the guide rail 35 and the mover of the feed screw mechanism 34, the first and second mapping sensors 53a and 53b are moved up and down in the Z-axis direction. It is possible to move.

Further, in the mapping device 21 provided in the load port 2 of the present embodiment, the air cylinder 40 is positioned below the support shaft 38 as a drive source of the mapping sensor drive mechanism 45 that drives the swing frame 39 to swing. As shown in FIG. The rod of the air cylinder 40 is engaged with the lower part of the lever 41 fixed to the support shaft 38. Further, the bracket 32 is provided with a stopper member 42 at a position where it comes into contact with the lower portion of the lever 41 when the swinging frame 39 performs a swinging operation in order to limit the inclination angle of the swinging frame 39. The stopper member 42 is provided with a damper using a spring or fluid pressure in order to minimize vibration due to collision with the lower portion of the lever 41. Further, here, there is provided a spring member (not shown) that constantly urges the swing frame 39 toward the origin position where the swing frame 39 is in an upright posture.

Further, the mapping device 21 of the present embodiment is a horizontal member that is a part of the swing frame 39 and is disposed above the door 19 and extends in the X-axis direction parallel to the port door 19 and the horizontal axis C. 44, the optical axes 51a and 51b of the two pairs of transmitted light sensors 50a and 50b are arranged in parallel to the horizontal axis C extending in the X-axis direction. By providing these two optical axes 51a and 51b, the mapping device 21 of the present embodiment is not possible with a conventional well-known mapping device having only a pair of transmitted light sensors 50. Not only the semiconductor wafer 3a having a diameter but also a semiconductor wafer 3b having a smaller diameter can be detected.

The first transmitted light sensor 50a protrudes from the horizontal member 44 of the swing frame 39 toward the FOUP 5 placed on the stage 15, and is paired with a pair of first support members 52a that are separated from each other. One mapping sensor 53a is fixed. In the first mapping sensor 53a, a first light projector 36a for detecting a semiconductor wafer 3a having a diameter of 300 mm and a first light receiver 37a for receiving detection light emitted from the first light projector 36a are opposed to each other. So that it is fixed. Here, the optical axis for detecting the semiconductor wafer 3 irradiated to the first light receiver 37a by the first projector 36a is defined as a first optical axis 51a. The first mapping sensor 53a is symmetrical with respect to the center line C ′ in the Y-axis direction passing through the center of the semiconductor wafer 3a accommodated in the FOUP 5 positioned and placed on the stage 15. A projector 36a and a first light receiver 36b are arranged. Further, the separation distance in the horizontal plane between the first light projector 36a and the first light receiver 37a is smaller than the separation distance on both side surfaces of the FOUP body 30 and is smaller than the separation dimension on both side surfaces of the open cassette 43. It is set to be large.

The second transmitted light sensor 50b has the same configuration as the first transmitted light sensor 50a, and protrudes from the horizontal member 44 of the swing frame 39 toward the FOUP 5 placed on the stage 15, and A pair of second mapping sensors 53b are fixed by two second support members 52b that are separated from each other. In the second mapping sensor 53b, in order to detect the semiconductor wafer 3b having a diameter of 200 mm, the second light projector 36b and the second light receiver 37b that receives the detection light emitted from the second light projector 36b face each other. So that it is fixed. Here, the optical axis for detecting the semiconductor wafer 3 irradiated to the second light receiver 37b by the second projector 36b is defined as a second optical axis 51b. The second mapping sensor 53b is symmetric with respect to the center line C ′ in the Y direction passing through the center of the semiconductor wafer 3b accommodated in the open cassette 43 positioned and placed on the stage 15. The light projector 36b and the second light receiver 36b are arranged. Further, the separation distance in the horizontal plane between the second projector 36 b and the second light receiver 37 b is set to be smaller than the separation dimension on both side surfaces of the open cassette 43. The transmitted light sensors 50a and 50b not only detect the presence / absence of the semiconductor wafer 3 in the wafer cassette, but also two semiconductor wafers 3 are mounted on the same shelf plate, or have different steps at both ends. It is one of the important roles to detect an abnormal placement state such as being placed in an inclined state on the shelf board.

  Next, the arrangement of the first optical axis 52a and the second optical axis 52b will be described. As described above, the first optical axis 51a is configured to detect the semiconductor wafer 3a having a relatively large diameter, and the second optical axis 51b is configured to detect the semiconductor wafer 3b having a relatively small diameter. When detecting the semiconductor wafer 3, the position of the semiconductor wafer 3 that is deeper than the edge of the semiconductor wafer 3 accommodated in the wafer cassette, that is, the end closest to the door 19, is detected. I have to. This is because, when the peripheral portion of the semiconductor wafer 3 is detected, the semiconductor wafer 3 is slightly displaced and moved to a deep position in the FOUP 5, or the vibration of the mapping device 21 when the mapping device 21 is moved up and down. Since the optical axes 51a and 51b may swing in the front-rear direction, the optical axes 51a and 51b may not be shielded by the semiconductor wafer 3 and may lead to detection results different from the actual mounting state. This is to prevent these erroneous detections.

Therefore, also in the mapping apparatus 21 of the present embodiment, the optical axes 51 a and 51 b are located at a predetermined distance from the peripheral edge of the semiconductor wafer 3, in other words, the peripheral edge of the semiconductor wafer 3 in order to perform detection reliably. A position offset by a predetermined distance from the center toward the center is passed. The second mapping sensor 53b is closer to the swing frame 39 than the first mapping sensor 53a, in other words, is located farther than the first mapping sensor 53a with respect to the container placed on the stage 15. Has been placed. The open cassette 43 is an open-type box-shaped container and has a simple structure that does not have any members necessary for maintaining the inside in a sealed state, and therefore can be closer to the mapping device 21 than the FOUP 5. Because. On the other hand, the FOUP 5 has a configuration in which the lid 18 separated from the main body 30 becomes an obstacle and is less likely to approach the first mapping sensor 53a than the open cassette 43. Therefore, in the mapping apparatus 21 of the present embodiment, the first projector 36a and the first light receiving unit are used so that the first optical axis 51a can pass through a position that is recessed by a predetermined distance from the peripheral portion of the semiconductor wafer 3a. The separation distance from the light projector 37a is configured to be greater than the separation distance between the second light projector 36b and the second light receiver 37b. Further, the first light projector 36a and the light receiver 37a are configured to be the second light projector. It protrudes from the swing frame 39 and is fixed so as to be closer to the FOUP 5 side mounted on the stage 15 than the arrangement position of 36b and the light receiver 37b.

Further, in the first mapping sensor 53a and the second mapping sensor 53b of the present embodiment, the optical axes 51a and 51b are parallel to each other in plan view, and further, the stage 15 and various types placed on the stage. It is supported by the swing frame 39 and the support members 52a and 52b so as to be orthogonal to a center line C ′ parallel to the Y axis passing through the center position of the semiconductor wafer 3 accommodated in the wafer cassette. In addition, when the swing frame 39 is at the stand-by position upright in the vertical direction, the optical axes 51a and 51b of the present embodiment are arranged to be horizontal at the same height position. The heights of 51b may be different from each other. Furthermore, in order to detect the semiconductor wafer 3 arranged horizontally, the optical axes 51a and 51b are arranged so as to extend in parallel with the X-axis direction. The optical axes 51a and 51b are not sufficiently shielded by the semiconductor wafer 3, and there is a possibility that a trouble of receiving an erroneous detection result may occur. Refer to FIG. Therefore, in another embodiment of the present invention, the projectors 36a and 36b and the light receivers 37a and 37b are arranged at different height positions. As a result, the respective optical axes 51a and 51b are irradiated at a predetermined angle in the vertical direction with respect to the semiconductor wafer 3, so that the optical axes 51a and 51b are reliably shielded by the semiconductor wafer 3 and an erroneous detection result. Will not be received. Refer to FIG. Since the thickness of the semiconductor wafer 3 is specified to be reduced as the diameter is reduced, the embodiment in which the optical axis is inclined is particularly effective for reliably detecting the semiconductor wafer 3b having a small diameter. .

Next, the cassette adapter 60 of the present embodiment will be described with reference to FIGS. FIG. 8A is a schematic view of the cassette adapter 60 according to the present embodiment as viewed from above, and FIG. 8B is a schematic view of the cassette adapter 60 according to the present embodiment as viewed from below. FIG. 9 is a schematic diagram showing the operation of the cassette identification unit 62 provided in the cassette adapter 60 of the present embodiment. The cassette adapter 60 is mounted and fixed on the stage 15, and the open cassette 43 having a different shape and containing a semiconductor wafer 3 b having a relatively small diameter such as 200 mm or 150 mm on the upper surface is not only mounted at a predetermined position. The type of the opened open cassette 43 can be identified. On the upper surface of the cassette adapter 60, a cassette guide 61 for mounting several types of open cassettes 43 having different shapes at predetermined positions is screwed at predetermined positions. The cassette guide 61 includes cassette guides 61a and 61b for positioning the front end portion of the open cassette 43 and cassette guides 61c and 61d for positioning the rear end portion. The cassette guides 61a and 61b at the front end and the cassette guides 61c and 61d at the rear end have a symmetrical shape, and are arranged symmetrically with respect to the center line C ′ in the Y-axis direction. The guide 61 has a shape having a notch corresponding to the outer edge of the corresponding open cassette 43 in order to correspond to the end of the open cassette 43 of different types. In the cassette adapter 60 of the present embodiment, of the notches formed in each cassette guide 61, the outer notch is for 200 mm with respect to the center line C ′ that is the center line in the Y direction of the cassette adapter 60. The open cassette 43 is positioned, and the inner notch is formed so as to position the open cassette 43 for 150 mm with respect to the center line C ′.

Further, in the vicinity of the cassette guide 61, a cassette identification unit 62 that is pushed downward by placing each open cassette 43 is provided at a position corresponding to each open cassette 43. The type of the open cassette 43 placed on the cassette adapter 60 can be identified by the on / off signal from the cassette identifying unit 62. The cassette identification unit 62 includes a detection lever 63 whose cross-sectional shape is substantially “<” and a transmitted light type optical sensor 65 having an optical axis 64 that is shielded by the operation of the detection lever 63. Yes. Refer to FIG.

The detection lever 63 is arranged such that a cassette contact portion 66 formed at one end penetrates a through hole 67 formed in the cassette adapter 60 from the lower surface of the cassette adapter 60 and protrudes from the upper surface of the cassette adapter 60. Yes. A through hole is formed in the horizontal direction at the other end of the detection lever 63, and a horizontal shaft 68 is inserted into the through hole. The horizontal shaft 68 is fixed to the lower surface of the cassette adapter 60 via a substantially U-shaped support block 69. With this configuration, the detection lever 63 is supported rotatably about the central axis of the horizontal shaft 68, and the cassette contact portion 66 formed at one end of the detection lever 63 has the cassette adapter 60 lower surface and the cassette adapter 60. It is possible to advance and retreat between the upper surface.

Further, the cassette identification portion 62 is provided with a spring member (not shown) that urges the detection lever 63 in a direction in which the cassette abutment portion 66 protrudes from the upper surface of the cassette adapter 60, and the cassette adapter 60 is in a horizontal state. The cassette abutment portion 66 is prevented from falling downward even if it is placed. This spring member has an urging force that causes the cassette abutment portion 66 to protrude from the upper surface of the cassette adapter 60, but does not have an urging force that supports the load of the open cassette 43. The detection lever 63 biased by the spring member protrudes toward the upper surface of the cassette adapter 60. The end of the through hole 67 formed in the cassette adapter 60 serves as a stopper, and this end is abutted against the end. The rotational movement is regulated by contact. With this structure, when no load is applied to the cassette contact portion 66, the cassette contact portion 66 protrudes from the upper surface of the cassette adapter 60, but when the open cassette 43 is properly placed on the cassette adapter 60. The lower surface of the open cassette 43 comes into contact with the cassette contact portion 66, and the detection lever 63 swings around the horizontal shaft 68 under the load of the open cassette 43 and is pressed downward. Become.

A light shielding dog 70 for shielding the optical axis 64 of the optical sensor 65 fixed to the lower surface of the cassette adapter 60 is formed at a position facing the cassette contact portion 66 of the detection lever 63. The advancing / retreating operation is performed together with the contact portion 66. With this structure, when the open cassette 43 is not placed on the cassette adapter 60, the light-shielding dog 70 is also connected to the cassette abutting portion 66 that is biased by the 66 spring member and protrudes from the upper surface of the cassette adapter 60. Move towards. At this time, since the light shielding dog 70 is in the retracted position with respect to the optical axis 64, the light irradiated from the light projecting unit is detected by the light receiving unit. When the open cassette 43 is placed on the cassette adapter 60, the light shielding dog 70 also moves downward in conjunction with the cassette abutting portion 66 pressed downward by the load of the open cassette 43. The optical axis 64 irradiated from the light part is blocked by the light shielding dog 70. It is possible to detect the mounting state of the open cassette 43 by the light shielding and retracting operation with respect to the optical axis by the light shielding dog 70.

Two cassette identification units 62 are provided for each type of open cassette 43, and it is considered that the open cassette 43 is normally placed only after these two cassette identification units 62 react. When only one of the two cassette identification units 62 is reacting, it is recognized that the open cassette 43 is not normally placed, and the load port 2 is normally loaded. The transition to the next operation is stopped until it is recognized that it has been placed. The wiring of the optical sensor 65 provided in each cassette identification unit 62 is connected to the male connector 71 provided at the end of the cassette adapter 60. When the male connector 71 is fitted to the control unit 72 included in the load port 2 of this embodiment and the female connector connected via the cable, the control unit 72 recognizes the on / off signal of each optical sensor 65. I can do it. In addition, a signal line for recognizing the presence of the connector 71 cassette adapter 60 is connected to the female connector from the control unit 72, and this signal cable is turned on when the connectors 71a and 71b are fitted. The signal can be detected. Furthermore, the control unit 72 supplies power for operating each optical sensor 65 via the connectors 71a and 71b. With the above configuration, the control unit 72 can identify the type of the open cassette 43 placed on the cassette adapter 60.

Next, a lower surface of the cassette adapter 60, that is, a surface that comes into contact with a member provided on the stage 15 will be described with reference to FIG. On the lower surface of the cassette adapter 60, a positioning block 74 in which a groove 73 having a V-shaped cross section for positioning is embedded in three places. The positioning block 74 is arranged at a position facing the positioning pin 22 erected so as to draw an isosceles triangle on the stage 15, and the V-shaped groove 73 formed in each positioning block 74 has each The rotation angle in the horizontal plane is adjusted so that the straight line connecting the vertices of the V-shaped cross section passes through the straight lines from the vertices of the isosceles triangle drawn by the positioning pins 22 to the center of gravity, and the cassette adapter 60 is positioned. A so-called kinematic coupling mechanism is formed which is automatically positioned at a predetermined position simply by being placed so that the V-shaped groove 73 is in contact with the top of the pin 22.

A rectangular recess 75 cut to a depth of about 10 mm is formed at the substantially central portion of the lower surface of the cassette adapter 60, and a flat locking plate 76 is fixed so as to cover almost half of the recess 75. Has been. When the cassette adapter 60 is placed on the stage 15, the recess 75 and the locking plate 76 are disposed so as to correspond to the operation of the locking hook 23 provided in the stage 15. The locking hook 23 is provided with a clamp claw 78 formed with a thin tip portion, and the clamp claw 78 is rotated and moved forward and backward by a driving means (not shown) such as an air cylinder or a motor to lock the hook. The position and the unlock position can be switched, and the cassette adapter 60 and the FOUP 5 placed on the positioning pin 22 standing on the stage 15 can be fixed to the stage 15. Further, at a position corresponding to the detection switch 31 disposed on the stage 15 on the lower surface of the cassette adapter 60, a thickness dimension that allows the detection switch 31 to be depressed when the cassette adapter 60 is normally placed on the positioning pin 22. Two spacers 77 having the above are disposed.

Here, in the load port 2 of the present embodiment, three positioning pins 22 are arranged on the stage 15, and when two of the predetermined detection switches 31 are pressed, the control unit 72 causes the cassette adapter 60 to It is supposed to be placed. Further, when all the detection switches 31 arranged on the stage 15 are pressed, the control unit 72 determines that the FOUP 5 is placed on the stage 15. In the present embodiment, three detection switches 31 are arranged. However, the present invention is not limited to this, and an arbitrary number of detection switches 31 are arranged, and the placed object depends on the state of the pressed detection switch 31. It may be determined what it is. With the above configuration, when the cassette adapter 60 is normally placed on the positioning pin 22, the spacer 77 depresses the predetermined detection switch 31, and the control unit 72 places the cassette adapter 60 on the load port 2. Recognize that. Further, the control unit 72 that has received a signal transmitted by fitting the male connector 71 and the female connector recognizes that the preparation for placing the open cassette 43 on the cassette adapter 60 is completed. Here, the control unit 72 that recognizes that the preparation of the cassette adapter 60 has been completed transmits an operation command to the locking hook 23, and the locking hook 23 that has received the operation command causes the clamping claw 78 to be moved by driving means (not shown). The cassette adapter 60 is fixed on the stage 15 by moving to the lock position.

Next, the operation of the load port 2 of the present embodiment will be described in detail with reference to FIGS. FIG. 10A is a schematic view of the operation of the mapping device 21 when the FOUP 5 is placed on the load port 2 of the present embodiment as viewed from the positive direction of the X axis, and FIG. It is the schematic diagram seen from the direction. In FIG. 10B, the upper side shows the state where the mapping sensor 53 a is in the standby position with the center line C ′ in the Y-axis direction as the boundary line, and the lower side shows the mapping sensor 53 a moving forward toward the FOUP body 30. The state in the position is shown. FIG. 11A is a schematic view of the operation of the mapping device 21 when the open cassette 43 is placed on the load port 2 of the present embodiment via the cassette adapter 60, as seen from the X-axis positive direction. (B) is the schematic diagram seen from the Z-axis positive direction. In FIG. 11B, as in FIG. 10, the mapping sensor 53 b is in the standby position on the upper side with the center line C ′ in the Y direction as the boundary, and the mapping sensor 53 b is in the open cassette 43 on the lower side. The state which exists in the position which advanced ahead toward is shown. In the load port 2 of the present embodiment, a FOUP 5 that accommodates a semiconductor wafer 3 having a diameter of 300 mm, an open cassette 43a that accommodates a semiconductor wafer 3 having a diameter of 200 mm via a cassette adapter 60, and a semiconductor wafer 3 having a diameter of 150 mm. Three types of wafer cassettes, that is, the open cassette 43b to be accommodated, are mounted so that the semiconductor wafer 3 accommodated therein can be detected.

Here, the first mapping operation performed by the load port 2 for the FOUP 5 that is the first wafer cassette will be described. When the FOUP 5 is placed at a predetermined position on the stage 15, the control unit 72 provided in the load port 2 recognizes that the FOUP 5 is placed from the state of the pressed detection switch 31. Here, after the locking hook 23 is operated and the FOUP 5 is fixed, the stage drive mechanism 16 is operated, and the stage 15 is moved forward in the Y direction to the previously taught docking position. If it is recognized that the FOUP 5 has been placed, a relay (not shown) is activated in preparation for the mapping operation of the 300 mm semiconductor wafer 3a, and the supply of power to the second transmitted light sensor 50b is cut off. The signal circuit is switched so that the signal transmitted from the transmitted light sensor 50 a is received by the control unit 72.

Next, the control unit 72 operates the stage driving mechanism 16 so that the previously taught dock position stored in the storage means 79, that is, the lid 18 engaged with the FOUP main body 30 contacts the door 19. The stage 15 and the FOUP 5 are moved in the positive direction of the Y axis to the contact position. At this time, the door 19 is in a standby position (POS 0), which is a position where it can be docked with the lid 18 taught in advance by the door lifting mechanism 20, and is prepared for contact with the lid 18. When the FOUP 5 moves in the Y-axis positive direction and the lid 18 and the door 19 come into contact with each other, the control unit 72 operates the latch mechanism to integrate the door 19 and the lid 18 and the lid 18 and the FOUP main body. The engagement state with 30 is released. Thereafter, the control unit 72 operates the stage driving mechanism 16 to move the stage 15 backward with the FOUP body 30 on the stage 15 in the Y-axis minus direction to a previously taught position, thereby completely moving the FOUP body 30 and the lid 18. The first mapping sensor 53a is separated so that the semiconductor wafer 3a accommodated in the FOUP body 30 can be detected. The load port 2 of the present embodiment is configured to separate the FOUP main body 30 and the lid 18 by moving the stage 15 backward, but instead of this configuration, the door 19 is moved to the FOUP main body 30 by a known technique. The FOUP main body 30 and the door 19 may be separated by moving the door 19 back and forth with respect to the FOUP main body 30. In other words, the FOUP main body 30 and the door 19 move relative to each other in a direction away from each other, so that the separation of the FOUP main body 30 and the door 19 is completed, and the first mapping sensor 53a is placed inside the FOUP main body 30. The accommodated semiconductor wafer 3a can be detected.

When the operation of separating the lid 18 from the FOUP main body 30 is completed, the control unit 72 operates the stage driving mechanism 16 to fix the stage 15 on the first mapping standby position (POS1B) taught in advance. The FOUP main body 30 is moved together with the door lifting mechanism 20, and the door 19 and the mapping device 21 are moved down from the standby position (POS0) to the first mapping start position (POS1A) taught in advance. . The first mapping start position (POS1A) is lower than the upper surface of the FOUP main body 30 in the Z-axis direction and is higher than the semiconductor wafer 3a accommodated on the uppermost shelf formed on the FOUP main body 30. It is set to be a high position.

When the movement to the first mapping start position (POS1A) is completed, the control unit 72 operates the air cylinder 40 included in the mapping device 21 until the lever 41 contacts the stopper member 42. As a result, the swing frame 39 waiting in a vertically upright posture is tilted toward the FOUP body 30 by an angle α with the horizontal axis C as the central axis, and is fixed to the upper surface of the swing frame 39. The mapping sensor 53a moves from the origin position into the FOUP main body 30 by a distance L. At this time, the first optical axis 51a is at a higher position in the vertical direction than the semiconductor wafer 3a placed on the uppermost shelf in the FOUP body 30, so that the detection light emitted from the projector 36a is blocked. Irradiated to the light receiver 37a without being performed.

  Next, the control unit 72 operates the door elevating mechanism 20 to lower the door 19 and the mapping device 21 from the first mapping start position (POS1A) to the previously taught first mapping end position (POS1C). . The first mapping sensor 53a fixed to the upper surface of the swing frame 39 by this movement also moves from the first mapping start position (POS1A) to the first mapping end position (POS1C) as shown in FIG. , The distance H1 is lowered. The moving distance H1 is longer than the distance from the upper surface of the semiconductor wafer 3a placed on the uppermost shelf of the FOUP body 30 to the lower surface of the semiconductor wafer 3a placed on the lowermost shelf. The first detection unit 51a can scan the semiconductor wafer 3a with respect to all the shelves.

The controller 72 generates a first light receiver that is generated when the first optical axis 51a included in the first mapping sensor 53a is intermittently interrupted by the semiconductor wafer 3a accommodated in the FOUP body 30 in a shelf shape. Based on the change of the output signal sent from 37a, it is recognized that the semiconductor wafer 3a is accommodated in the FOUP main body 30, and the position information in the Z-axis direction when the first optical axis 51a is cut off is obtained. Save in the storage means 79. Here, based on data such as the vertical distance between the 300 mm semiconductor wafers 3a accommodated in the shelf of the FOUP main body 30 that has been taught and stored in advance and the thickness of the semiconductor wafer 3a itself, the control unit Reference numeral 72 denotes information on what level of the plurality of shelves formed in the FOUP main body 30 is placed, and the semiconductor wafer 3a accommodated therein has a different level. First mapping information indicating whether or not there is something stored obliquely is derived and stored in the storage means 79.

When the movement to the first mapping end position (POS1C) is completed, the control unit 72 operates the air cylinder 40 to return the swinging frame 39 that has been inclined by the angle α to the vertical posture that is the standby posture. The first mapping sensor 53a is moved backward by the distance L with respect to the FOUP body 30 and returned to the origin position. After the swing frame 39 returns to the vertical posture, the control unit 72 operates the door lifting mechanism 20 to move the door 19 and the mapping device 21 from the first mapping end position (POS1C) to the first taught in advance. Is lowered to the transport standby position (POS1D) and stored in the lower portion of the load port 2. Finally, the control unit 72 operates the stage driving mechanism 16 to move the stage 15 forward together with the FOUP main body 30 on the stage 15 to the first wafer transfer position (POS1E) taught in advance. The series of first mapping operations is thus completed.

When the operation of acquiring the series of first mapping information is completed, the control unit 72 transmits the first mapping data stored in the storage unit 79 to the upper control device 11. As a result, the higher-level control device 11 allows the semiconductor wafer 3a to be stored in the FOUP main body 30, information on what level of the plurality of shelves is mounted, and the contained semiconductors. It is possible to obtain information as to whether or not there are wafers 3a that are stored at different angles in different stages. Based on this information, the host control device 11 transmits an operation command to a control device (not shown) that controls the transfer robot 7 to transfer the semiconductor wafer 3a in the FOUP main body 30, so that the semiconductor wafer 3a is loaded. It is possible to omit a useless transfer operation for a shelf that is not placed, and it is also possible to select a specific shelf and transfer the semiconductor wafer 3a.

Next, the second mapping is performed on the open cassette 43a, which is a second wafer cassette placed on the load port 2 of the present embodiment via the cassette adapter 60 and containing the semiconductor wafer 3b having a diameter of 200 mm. The second mapping operation for acquiring information will be described in detail with reference to FIG. In order to acquire mapping information related to the open cassette 43 at the load port 2 of the present embodiment, first, the cassette adapter 60 is placed on the stage 15, and the control unit is connected to the male connector 71 provided in the cassette adapter 60. The female connector extended from 72 is connected. When the connection is completed, the control unit 72 provided in the load port 2 recognizes that the cassette adapter 60 is placed and operates the locking hook 23 to fix the cassette adapter 60 on the stage 15.

The target open cassette 43 is placed at a position defined by the positioning block 74 on the cassette adapter 60. Here, the control unit 72 determines that the second wafer cassette is mounted by the on / off signal of each sensor transmitted from the cassette identification unit 62, and operates a relay (not shown) in preparation for the mapping operation of the 200 mm semiconductor wafer 3b. Then, the supply of power to the first transmitted light sensor 50a is cut off and the supply of power to the second transmitted light sensor 50b is started, and a signal transmitted from the second transmitted light sensor 50b is received. The signal circuit is switched so as to be received by the control unit 72. Here, the control unit 72 operates the stage driving mechanism 16 to move the stage 15 together with the cassette adapter 60 and the open cassette 43a thereon to the second teaching standby position (POS2B) taught in advance, Then, the door elevating mechanism 20 is operated to move the door 19 and the mapping device 21 downward from the standby position (POS0) to the second mapping start position (POS2A) taught in advance. The second mapping start position (POS2A) is lower than the upper surface of the open cassette 43 and higher than the semiconductor wafer 3b accommodated on the uppermost shelf formed in the open cassette 43. Is set to In the first mapping operation, a step of separating the FOUP main body 30 and the lid 18 is necessary. However, the open cassette 43 is a container opened to the outside and has a lid for sealing the inside. There is no need for this separation operation.

When the movement to the second mapping start position (POS2A) is completed, the controller 72 operates the air cylinder 40 provided in the mapping device 21 until the lever 41 abuts against the stopper member 42, as in the first mapping operation. Let As a result, the swing frame 39 waiting in a vertically upright posture is tilted toward the open cassette 43 main body by the angle α with the horizontal axis C as the central axis, and is fixed to the upper surface of the swing frame 39. The second mapping sensor 53b moves from the origin position toward the inside of the open cassette 43 by a distance L. At this time, since the second optical axis 51b is at a higher position in the vertical direction than the semiconductor wafer 3b mounted on the uppermost shelf in the open cassette 43, the detection light emitted from the projector 36b is blocked. Irradiated to the light receiver 37b without being performed. As with the second mapping sensor 53b, the first mapping sensor 53a fixed to the upper surface of the swing frame 39 is predetermined with respect to the second mapping sensor 53b so as to move outside the open cassette 43. Therefore, the swing frame 39 will not collide with the outer frame of the open cassette 43.

Next, the control unit 72 operates the door lifting mechanism 20 to lower the door 19 and the mapping device 21 from the second mapping start position (POS2A) to the previously taught second mapping end position (POS2C). . By this movement, the second mapping sensor 53b fixed on the upper surface of the swing frame 39 is moved from the second mapping start position (POS2A) to the second mapping end position (POS2C) as shown in FIG. , It will fall by the distance H2. The moving distance H2 is longer than the distance from the upper surface of the semiconductor wafer 3b placed on the uppermost shelf of the open cassette 43 to the lower surface of the semiconductor wafer 3b placed on the lowermost shelf. The second detection unit 51b can scan the semiconductor wafer 3b with respect to all the shelf levels.

The control unit 72 generates a second light receiver that is generated when the second optical axis 51b of the second mapping sensor 53b is intermittently interrupted by the semiconductor wafer 3b accommodated in the open cassette 43 in a shelf shape. Based on the change of the output signal sent from 37b, it is recognized that the semiconductor wafer 3b is accommodated in the open cassette 43, and the position information in the Z-axis direction when the second optical axis 51b is cut off is obtained. Save in the storage means 79. Here, on the basis of data such as the vertical interval of the 200 mm semiconductor wafer 3b accommodated in the shelf of the open cassette 43 stored in advance and the thickness of the semiconductor wafer 3b itself, the control unit 72 determines the semiconductor wafer. 3 is information on the number of shelves of the plurality of shelves formed in the open cassette 43, and the semiconductor wafer 3b that is housed is stored obliquely at different levels. The second mapping information such as whether there is something is derived and stored in the storage means 79.

When the movement to the second mapping end position (POS2C) is completed, the control unit 72 operates the air cylinder 40 to return the swinging frame 39 that has been inclined by the angle α to the vertical posture that is the standby posture. Then, the second mapping sensor 53b is retracted by the distance L with respect to the open cassette 43 and returned to the origin position. After the swing frame 39 returns to the vertical posture, the control unit 72 operates the door elevating mechanism 20 to move the door 19 and the mapping device 21 from the second mapping end position (POS2C) to the second previously taught. Is lowered to the transport standby position (POS2D) and stored in the lower portion of the load port 2. Finally, the control unit 72 operates the stage driving mechanism 16 to move the stage 15 forward to the wafer transfer position (POS2E) taught in advance together with the cassette adapter 60 and the open cassette 43 thereon. The series of second mapping operations is thus completed. The first conveyance standby position (POS1D) taught in advance for the first mapping operation and the second conveyance standby position (POS2D) previously taught for the second mapping operation are the conveyance Since it is a retracted position so as not to interfere with the wafer transfer operation by the robot 7, it may be the same height position.

When the operation of acquiring the series of second mapping information is completed, the control unit 72 transmits the second mapping data stored in the storage unit 79 to the higher-level control device 11. As a result, the host control device 11 allows the semiconductor wafer 3b to be placed on the information on the number of shelves of the plurality of shelves formed in the open cassette 43, and the stored semiconductor wafers. It is possible to obtain information as to whether or not there is an item accommodated diagonally at different levels in 3b. Based on this information, the host control device 11 transmits an operation command to a control device (not shown) that controls the transfer robot 7 and transfers the semiconductor wafer 3b in the open cassette 43, so that the semiconductor wafer 3b is loaded. It is possible to omit a useless transfer operation for a shelf that is not placed, and it is possible to transfer a semiconductor wafer 3b by selecting a specific shelf.

Here, even if the same number of semiconductor wafers 3 can be accommodated, the height dimension in the Z-axis direction of the open cassette 43 and the open cassette 43 placed on the cassette adapter 60 of this embodiment is larger than that of the FOUP 5 for 300 mm. Therefore, the vertical height position of the second mapping start position (POS2A) is set to a position lower than the first mapping start position (POS1A). Further, among the shelf boards formed on the open cassette 43 placed on the cassette adapter 60 of this embodiment, the height position in the Z-axis direction of the lowest shelf board is formed inside the FOUP main body 30. Since the height of the shelf is higher than the height of the bottom shelf, the height of the second mapping end position (POS2C) in the Z-axis direction is the first mapping end position ( POS1C) is set at a higher position. The second mapping standby position (POS2B) at the time of mapping with respect to the open cassette 43 placed via the cassette adapter 60 of the present embodiment is the same as that at the time of mapping with respect to the FOUP main body 30 placed on the load port 2. The stage 15 is set at a position advanced closer to the door 19 than the first mapping standby position (POS2A) which is the Y direction position of the stage 15. This is because the second mapping sensor 53b for detecting the semiconductor wafer 3b is disposed at a position recessed in the horizontal direction with respect to the stage 15 as compared with the first mapping sensor 53a.

Next, a second embodiment of the cassette adapter 60 to which a cover for protecting the placed open cassette 43 is attached will be described with reference to FIG. FIG. 12 is a perspective view schematically showing the cassette adapter 60 of the second embodiment provided with the protective cover 80. Since the open cassette 43 is not a sealed container like the FOUP 5, it is not necessary to open and close the lid of the container, but the semiconductor wafer 3b accommodated in the open cassette 43 is exposed to the surrounding environment. Further, since the open cassette 43 placed on the cassette adapter 60 is not fixed on the stage 15 by the locking hook 23 unlike the FOUP 5, the operator mistakenly puts it into the open cassette 60 during the operation of the transfer robot 7. If touched, the placement position of the open cassette 43 moves, and the transfer robot 7 cannot be normally accessed.

Therefore, the cassette adapter 60 of the second embodiment is provided with a protective cover 80 that covers the periphery of the open cassette 43 to be placed. The protective cover 80 includes a cover body 81 that covers the upper surface and both side surfaces of the open cassette 43, and an opening / closing door 82. The cover main body 81 has a substantially U-shape when viewed from the front, and both ends are fixed to the cassette adapter 60 with screws. When the cassette adapter 60 is fixed to the stage 15, the surface facing the port opening 17 formed in the load port 2 and the surface opposite to this surface, that is, the surface where the operator accesses the open cassette 43. Is a shape open to the surroundings. Furthermore, the opening opened for access by the operator can be accessed without the operator's hand touching the cover body 81 when the operator places and removes the open cassette 43 from the cassette adapter 60. Thus, the upper surface and both side surfaces are also cut into the direction toward the port opening 17.

  The open / close door 82 is rotatably attached to the cover body 81 via a hinge, and has a shape capable of closing the opening of the cover body 81 formed for access by an operator. In addition, a handle 86 for facilitating opening and closing is provided on the front surface of the opening and closing door 82. In addition, stoppers 83 for restricting the position of the open / close door 82 when closed are provided on the left and right sides of the open / close door 82, and contact with an abutment portion 84 provided on the cover main body 81. Restrict movement.

Further, the cassette adapter 60 of the second embodiment is provided with a lock mechanism 85, and the door 82 can be locked and unlocked. The lock mechanism 85 can be switched between lock and unlock by transmitting an electrical signal to a solenoid provided therein. The lock / unlock signal is transmitted from the control unit 72 via the connector 71. It is sent to the lock mechanism 85. The lock mechanism 85 is electrically connected to the control unit 72 via the connector 71, and performs locking and unlocking operations according to operation signals transmitted from the control unit 72.

The operator manually places the open cassette 43 on a predetermined cassette adapter 60 and then inputs a transport start signal to the input means 12 provided in the EFEM 6. Receiving this signal, the control device 11 transmits a conveyance preparation start signal to the control unit 72 provided in the load port 2. The control unit 72 that has received the signal transmits a lock signal to the lock mechanism 85 to lock the open / close door 82, and then transmits a forward signal to the stage 15 to start the mapping operation. Here, the open / close door 82 is locked and engaged with the cover body 81, and the cassette adapter 60 is fixed to the stage 15 by the locking hook 23. Can be prevented from accessing. When the processing of the processing apparatus 4 is completed and all the semiconductor wafers 3b are accommodated in the open cassette 43, the operator inputs a transfer signal of the open cassette 43 to the control device 11 via the input means 12. Upon receiving this signal, the control device 11 transmits a lock release signal for the door 82 to the control unit 72, and the control unit 72 receiving the signal unlocks the lock mechanism 85 to release the lock state.

The internal space of the protective cover 80 formed by the cover main body 81 and the open / close door 82 in the closed position needs to have a volume that can accommodate at least the largest open cassette 43 placed on the cassette adapter 60. There is. However, if the protective cover 80 has a volume enough to accommodate the predetermined open cassette 43, for example, when the protective cover 80 is placed on the load port 2 corresponding to the semiconductor wafer 3a having a diameter of 300 mm, the semiconductor wafer 3a having a diameter of 300 mm passes. A large gap is generated between the port opening 17 having a possible area and the protective cover 80. When this gap is generated, the operator's hand enters the gap and comes into contact with the internal structure, resulting in injury, or dust from the outside flows into the EFEM 6 through the gap. There is a possibility that high internal cleanliness cannot be maintained.

Therefore, the protective cover 80 of the cassette adapter 60 of the present embodiment has a cross-sectional area in the XY axial plane so that a slight gap of about 5 mm is formed between the N peripheral edge of the port opening 17 and the protective cover 80. Is preferably the same as or slightly smaller than the area of the port opening 17 formed in the load port 2. By doing so, it is possible to prevent external dust from flowing into the EFEM 6 by causing clean air inside the EFEM 6 to flow out from the slight gap. In addition, since the amount of clean air flowing out to the outside is small, the positive pressure inside the EFEM 6 can be maintained.

In addition, the protective cover 80 with which the cassette dapter of a present Example is provided is made from the transparent polycarbonate from the reason that the inside is recognizable visually. Other than polycarbonate, a resin material such as acrylic or polyvinyl chloride may be used. Furthermore, although it is possible to make a metal material such as stainless steel or aluminum, it is desirable to provide a window covered with a transparent resin in order to recognize the internal state.

As described above with reference to the drawings, in the embodiment, the open cassette 43 contains a semiconductor wafer 3b having a diameter of 150 mm and 200 mm, and the sealed container 5 contains a semiconductor wafer 3a having a diameter of 300 mm and 450 mm. However, it goes without saying that the present invention is not limited to the above-described examples, and includes those that can be changed by those skilled in the art within the scope of the claims.

1 is a cutaway perspective view showing an outline of a semiconductor manufacturing system according to the present invention. It is sectional drawing which looked at the stage drive mechanism periphery of the load port in a present Example from the X-axis positive direction. It is a notch perspective view which shows the outline of the load port in a present Example. It is a perspective view which shows the wafer cassette used in a present Example. It is the perspective view which looked at the mapping apparatus of a present Example from the diagonally back of the load port. It is the top view which showed typically the detection part with which the mapping apparatus of a present Example is provided. It is explanatory drawing which showed typically the optical axis irradiated from the detection part of a present Example. It is a figure which shows the cassette adapter of a present Example. It is the figure which showed operation | movement of the cassette identification means with which the cassette adapter of a present Example is provided. It is explanatory drawing which shows operation | movement of the mapping apparatus with which the load port of a present Example is provided. It is explanatory drawing which shows operation | movement of the mapping apparatus with which the load port of a present Example is provided. It is a perspective view which shows the cassette adapter of the 2nd Example in this invention.

Claims (9)

A port opening;
A door covering the port opening;
A stage on which a first wafer cassette for storing semiconductor wafers having a first diameter in a shelf shape is placed at a predetermined position;
A cassette adapter that is detachably installed on the stage and mounts a second wafer cassette that accommodates semiconductor wafers having a second diameter in a shelf shape at a predetermined position;
A detection switch provided on the stage for detecting that the first wafer cassette or the cassette adapter is mounted;
A cassette identifying unit provided in the cassette adapter for detecting that the second wafer cassette is mounted;
A first mapping sensor for detecting a semiconductor wafer having the first diameter;
A second mapping sensor for detecting a semiconductor wafer having the second diameter;
A mapping sensor driving mechanism for moving the first and second mapping sensors forward and backward with respect to the wafer cassette;
An elevating mechanism for moving the first and second mapping sensors up and down in an up and down direction;
When the first wafer cassette is placed, a signal sent from the first mapping sensor is received;
And a control unit that receives a signal sent from the second mapping sensor when the second wafer cassette is placed. The first mapping sensor has a first projector and a first light receiver,
The distance between the first light projector and the first light receiver is:
Smaller than the horizontal dimension of the opening formed in the first wafer cassette and larger than the horizontal dimension of the opening formed in the second wafer cassette;
The second mapping sensor has a second projector and a second light receiver,
The distance between the second light projector and the second light receiver is:
The horizontal dimension of the opening formed in the first wafer cassette is smaller than the horizontal dimension of the opening formed in the second wafer cassette, and is smaller than the horizontal dimension of the opening formed in the second wafer cassette. Item 2. The load port according to Item 1. The first projector and the first receiver, and the second projector and the second receiver are:
A pair of swing frames that are swingable about a horizontal axis extending in the X-axis direction parallel to the door are attached in pairs,
The first projector and the first light receiver are closer to the wafer cassette placed on the stage than the second light projector and the second light receiver in the same horizontal plane. The load port according to claim 2, wherein the load port is arranged. The first optical axis irradiated from the first projector is:
The first wafer cassette is disposed at a predetermined angle with respect to the surface of the semiconductor wafer having the first diameter housed in the first wafer cassette,
The second optical axis irradiated from the second projector is
4. The device according to claim 2, wherein the second wafer cassette is disposed so as to have a predetermined angle with respect to a surface of the semiconductor wafer having the second diameter accommodated in the second wafer cassette. 5. Load port. The cassette adapter covers the periphery of the second wafer cassette, and an opening for carrying in and out the semiconductor wafer having the second diameter with respect to the second wafer cassette is formed by the transfer means. The load port according to any one of claims 1 to 4, further comprising a protective cover. The load port according to claim 5, wherein an area of the opening formed in the protective cover is substantially the same as an opening area of the port opening. The load port according to claim 6, wherein a part of the protective cover includes an openable / closable door for accessing the second wafer cassette. A load port according to claim 1 to claim 7,
Storage means for storing position information relating to the first and second wafer cassettes taught in advance;
The controller is
When the first wafer cassette is placed, the positional information regarding the first wafer cassette stored in the storage means is read, and an operation command is transmitted to the mapping sensor driving mechanism and the lifting mechanism,
When the second wafer cassette is placed, the positional information related to the second wafer cassette stored in the storage means is read, and an operation command is transmitted to the mapping sensor driving mechanism and the lifting mechanism. Features load port. 9. The load port according to claim 1, further comprising: holding and transporting the semiconductor wafer housed in the wafer cassette based on mapping information transmitted from the load port. A transfer apparatus comprising a transfer robot.

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