JPH11284046A - Wafer carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve work efficiency and to carry a wafer advantageously in terms of cost. SOLUTION: This device 1 is provided with an elevation arm 2 which turns into a longitudinal shape projected from a device main body 10 in a Y-axis direction and made movable at least in an X-axis direction and a Z-axis direction, and a first hand 3 and a second hand 4 respectively connected separately for a fixed distance in the longitudinal direction of the elevation arm 2. In this case, the first hand 3 and the second hand 4 are respectively provided with quartz board hanging parts 30 and 40 for hanging a quartz board 5 housing the plural wafers 11, so as to be bridged between the respective hands 3 and 4 and respectively provided tray mounting parts 32 and 42 for mounting a cassette tray 6, on which a cassette 60 housing the plural wafers 11 is mounted so as to be bridged between the respective hands 3 and 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for transferring a wafer to a high-temperature heating furnace together with the quartz boat while suspending a quartz boat containing a plurality of wafers.

[0002]

2. Description of the Related Art Normally, a semiconductor chip is formed by forming a plurality of circuit elements on the surface of a wafer such as silicon through various processes and then dividing the wafer for each circuit element. Formed by The above-mentioned steps include a step of forming an oxide film on the wafer surface, a photolithography step for forming a resist, a step of diffusing impurities, and a step of forming an electrode. Each of these steps is performed using a predetermined device,
The movement of the wafer between the apparatuses is performed in a state where a plurality of wafers are accommodated in a cassette made of metal or the like.

As is well known, the diffusion step is a step in which impurities are diffused from the surface of the wafer to the inside thereof, and the region in which the impurities are diffused is made P-type or N-type. Since the diffusion rate increases as the temperature increases, the diffusion must be performed at a high temperature of about several hundred degrees to about 1000 degrees (depending on the type of the impurities) in order to diffuse the impurities into the inside of the wafer. On the other hand, if any metal, for example, sodium, has adhered to the surface of the oxide film of the wafer, a problem occurs in that the adhered substance is taken into the oxide film in the high-temperature diffusion step. In order to avoid such a problem, diffusion of impurities is performed in a high-temperature diffusion furnace made of quartz or the like. In addition, in the case of a cassette made of metal or the like, there is a concern that sodium or the like may adhere to the wafer and diffuse the wafer. By doing so, a diffusion process is performed.

Meanwhile, a quartz boat containing a plurality of wafers is transferred to a vicinity of a high-temperature diffusion furnace by a wafer transfer device as shown in FIG. The wafer transfer apparatus 1 has an elevation arm 2 projecting from the apparatus main body 10 in the Y-axis direction and movable in the X-axis direction and the Z-axis direction. And a pair of hands 3 and 4 connected to each other at a predetermined distance in the direction. These hands 3 and 4 are connected to each other so as to protrude from the elevation arm 2 in the X-axis direction, and quartz holding portions 30 and 40 are provided at the ends thereof. Grooves 31, 41 extending in the X-axis direction and recessed downward are formed on the upper surfaces of these holding parts 30, 40. That is, holding the handle 50 provided with the quartz boat 5 in these grooves 31 and 41, the quartz boat 5 is bridged between the hands 3 and 5, and in this state, the quartz boat 5 Is transported.

As described above, the quartz boat 5 includes:
The wafer 11 stored in the cassette is transferred, and the transfer of the wafer is automatically performed by, for example, a transfer device (not shown) having a hand capable of holding the wafer.
For this reason, the quartz boat 5
In order to be able to transfer the wafer 11 to the above, it is necessary to place the quartz boat 5 and the cassette in predetermined positions, respectively. Usually, the cassette in which the wafers 11 to be subjected to the diffusion process are accommodated is accommodated in a state of being placed on a plate-like tray or the like, for example, on a shelf adjacent to the transfer device. For this reason, it is necessary to take out the cassette together with the tray from a shelf or the like, and position and place the cassette in a predetermined place.

[0006] Such work is performed manually by an operator or automatically by a predetermined device. However, while the work efficiency is extremely poor with human power, the work efficiency is improved by using a predetermined device, but is disadvantageous in cost because a new device different from the above-described wafer transfer device is required. .

The present invention was conceived under the circumstances described above, and aims to improve work efficiency and
It is an object of the present invention to be able to transfer a wafer in a cost-effective manner.

[0008]

DISCLOSURE OF THE INVENTION In order to solve the above problems, the present invention employs the following technical means.

That is, the wafer transfer apparatus provided by the present invention has an elongated shape projecting from the apparatus main body in the Y-axis direction and is movable at least in the X-axis direction and the Z-axis direction. And a first hand and a second hand which are respectively connected at a predetermined distance in a longitudinal direction of the elevation arm, wherein the first hand and the second hand are provided.
Each of the hands has a quartz boat suspension supporting portion in which a quartz boat containing a plurality of wafers is suspended so as to bridge between the hands, and a cassette containing a plurality of wafers. Each of the trays is provided with a tray mounting portion for mounting the cassette tray on which the cassette is mounted so as to bridge between the hands.

[0010] In the above configuration, the quartz boat can be transported in a state in which the quartz boat is bridged between the quartz boat suspension supports of the hands as in the related art. In addition, since each of the hands has a tray mounting portion, the tray can be transported by mounting the tray so as to bridge between the tray mounting portions. . As described above, since the cassette may be stored on a shelf or the like in a state of being placed on the tray, in this case, the cassette placed on the tray is taken out by the wafer transfer device. Can be transported.

As described above, the wafer transfer apparatus can transfer not only a quartz boat but also a cassette. For this reason, the cassette stored in the shelf or the like can be automatically performed without having to be taken out manually, and the working efficiency can be improved. In addition, since the cassette can be taken out and transported from shelves by a device that transports the quartz boat near the high-temperature diffusion furnace,
There is no need to separately provide a device for taking out a cassette from a shelf or the like and transporting it. Therefore, in the above-described wafer transfer device, it is possible to reduce the manufacturing cost.

In a preferred embodiment of the present invention, the first hand and the second hand are L-shaped, V-shaped or U-shaped, and are rotatable around the Z-axis. Also, the quartz boat hanging supports of the respective hands are projected from the elevation arm in the X-axis direction, and the quartz boat is suspended by these quartz boat hanging supports, and the wafer is transported together with the quartz boat. And a state in which the tray mounting portions of the respective hands are respectively protruded from the elevation arm in the X-axis direction, and the trays are mounted by these tray mounting portions and the wafers are transferred together with the trays. It can be configured as possible.

In the above configuration, since each of the hands is rotatable in an L-shape, V-shape or U-shape, the quartz boat hanging supports of each hand are each rotated by simply rotating each hand. It is possible to select between a state in which the tray arm protrudes from the elevation arm in the X-axis direction and a state in which the tray mounting portions protrude from the elevation arm in the X-axis direction.

Further, since each of the hands is L-shaped, V-shaped or U-shaped, in a state where each of the quartz boat suspension supports protrudes from the elevation arm, each of the quartz boat suspension supports is viewed in a plan view. It is assumed that the tray mounting portion is hidden under the elevation arm. On the other hand, in a state in which the tray mounting portions protrude, the quartz boat hanging supports are hidden by the elevation arms. As described above, in the wafer transfer device, both the quartz boat hanging support portion and the tray mounting portion of each hand do not protrude from both sides of the elevation arm, and only one of the use arms protrudes. State.

For this reason, in the above-described wafer transfer device, the portion protruding from the elevation arm in the X-axis direction during use can be minimized, and the space efficiency around the wafer transfer device can be improved. . That is, for example, considering the case where the quartz boat is picked up from a predetermined place or placed in a predetermined place, an unused hand portion is placed in the cassette, a shelf in which the cassette is stored, or a high-temperature diffusion furnace. In order not to interfere with an arm or the like for carrying the quartz boat, it is not necessary to widely separate cassettes and shelves. Further, since the space efficiency around the wafer transfer device can be improved, the distance to which the elevation arm should be moved can be set small. Therefore, the size of the wafer transfer device can be reduced.

Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a perspective view showing an example of a wafer transfer apparatus according to the present invention, FIG. 2 is a plan view of the wafer transfer apparatus, and FIGS. It is a principal part perspective view for demonstrating operation | movement. In addition,
In the drawings referred to for describing the present embodiment,
The same reference numerals are given to members and elements equivalent to those depicted in the drawings referred to for describing the conventional example.

As shown in FIG. 1, the wafer transfer device 1
Is a longitudinally extending elevation arm 2 projecting from the apparatus main body 10 in the Y-axis direction, and a first hand 3 and a second hand 4 connected to the elevation arm 2 at a predetermined distance in the longitudinal direction thereof. , And is generally configured. As shown in FIG. 2, the wafer transfer apparatus 1 can select between a state in which the quartz boat 5 is suspended between the hands 3 and 4 and a state in which the cassette tray 6 is placed. Has been made.

As shown in FIG. 1, the elevation arm 2 is connected to a slider 12 slidable in the Z-axis direction with respect to the apparatus main body 10 so as to be slidable in the X-axis direction. Have been. That is, the elevation arm 2 is movable with respect to the apparatus main body 10 in the X-axis direction and the Z-axis direction.

As best seen in FIGS. 1 and 2,
The first hand 3 has an L-shape having a quartz boat suspension section 32 and a tray mounting section 33, and is connected to the elevation arm 2 so as to be rotatable around the Z axis with its corner as a center. I have.

A holding member 30 made of quartz or the like is attached to the quartz boat suspension support 32. The holding member 30 has a groove 31 extending in the longitudinal direction of the quartz boat suspension support 32 and recessed downward.
The handle 50 provided on the quartz boat 5 is held in the groove 31. On the other hand, the tray mounting portion 33 has a positioning pin 34 that is fitted into a positioning hole 61 formed in the cassette tray 6.

As shown in FIGS. 2 and 3, the first hand 3 is rotatable around the Z axis by a first rotating mechanism 7. As best shown in FIGS. 3A and 3B, the first rotation mechanism 7 includes a first rotation shaft 70 rotatably inserted and held around the Z-axis at the distal end of the elevation arm 2. An elliptical first rotating member 71 having one end integrally connected to the upper end of the first rotating shaft 70, and a shaft provided at the other end of the first rotating member 71. A piston 73 rotatably connected to the portion 71a and slidable in the cylinder 72 to extend and contract in the Y-axis direction; and a drive source (not shown) for expanding and contracting the piston 73. It is configured.

In the first rotating mechanism 7, the rotating shaft 70
The lower end of the first hand 3 is integrally connected at a corner of the first hand 3 so that the first hand 3 rotates integrally with the first rotating shaft 70. That is, since the first rotating shaft 70 is integrated with the first rotating member 71, if the first rotating member 71 is rotated by expanding and contracting the piston 73, the first rotating shaft 70 is rotated. 70
Is rotated, and eventually, the first hand 3 is rotated. In the present embodiment, the piston 7
3 is contracted, the tray mounting portion 33 as shown in FIG.
When the piston 73 is extended, the quartz boat suspension support 32 as shown in FIG. 3B projects from the elevation arm 2 in the negative X-axis direction when the piston 73 is extended. It is made to be in the state where it was done.

As best seen in FIGS. 1 and 2,
The second hand 4 has an L-shape having a quartz boat suspension support portion 42 and a tray mounting portion 43, similarly to the first hand 3. In the second hand 4, a portion corresponding to the quartz boat suspension portion 32 in the first hand 3 is a tray mounting portion 43, while a portion corresponding to the quartz tray mounting portion 33 is a boat suspension portion. 42. That is, the first hand 3 and the second hand 4 are targets in a plan view. Needless to say, the holding member 40 having the groove 41 is attached to the quartz boat hanging support 42, and the positioning pin 44 is formed on the tray mounting portion 43.

The first hand 3 is moved by a second rotation mechanism 8 having the same configuration as that of the first rotation mechanism 7.
It is rotatable around the axis. That is, the second rotation mechanism 8 has a second rotation member 81 that is rotated by expansion and contraction of a piston 83, and the second hand 4 is configured to rotate the second rotation member 81 and the second rotation shaft 80. And is rotated by the second rotating member 81.

As shown in FIG. 2, in the wafer transfer apparatus 1 having the above-described structure, the hands 3 and 4 are rotated by the expansion and contraction of the pistons 73 and 83, and the quartz of the hands 3 and 4 is rotated. The state in which the boat suspension portions 32 and 42 protrude from the elevation arm 2 in the X-axis direction and the state in which the tray mounting portions 33 and 43 protrude can be selected. As shown in FIG. 2, in a state in which the quartz boat suspensions 32 and 42 protrude from the elevation arm 2, the tray mounting parts 33 and 43 are located below the elevation arm 2. The trays 33, 4
In a state where 3 protrudes from the elevation arm 2, each of the quartz boat suspensions 32 and 42 is hidden under the elevation arm 2.

When the quartz boat suspension supports 32 and 42 protrude from the elevation arm 2 in the X-axis direction, the handles 50 provided on both ends of the quartz boat 5 are attached to the quartz boats 50 and 50, respectively. Boat suspension 3
The quartz boat 5 is conveyed in such a manner that the quartz boat 5 is held by the holding members 30 and 40 and suspended between the quartz boat suspending portions 32 and 42 so as to bridge the quartz boat 5. At this time, if the wafer 11 is accommodated in the quartz boat 5, the wafer 11 is transferred. On the other hand, when the tray mounting portions 43 protrude, the positioning pins 34, 44 are fitted into positioning holes 61, 61 formed at both ends of the cassette tray 6, and the tray mounting portions 33, 43 are fitted. The cassette tray 6 is placed in such a manner that the cassette tray 6 is placed so as to bridge it.
Is transported.

Next, the use state of the wafer transfer apparatus 1 will be described with reference to FIGS. FIG. 4 is a diagram showing a layout around the wafer transfer device.
FIG. 5 is a view for explaining a state in which the cassette tray is lifted by the wafer transfer apparatus, FIG. 6 is a view for explaining a state in which the quartz boat is lifted by the wafer transfer apparatus, and FIG. FIG. 5 is a diagram for explaining switching of a transport target by the apparatus, and is a diagram corresponding to a state viewed in the direction of arrow A in FIG. 4.

The above-described wafer transfer device 1 in the present embodiment
Is a device which takes out the cassette 60 stored in the shelf 8 and transports the quartz boat 5 on which the wafers 11 are transferred from the cassette 60 to the plate-like arm member 90 arranged near the high-temperature diffusion furnace 9. (See FIG. 4). The quartz boat 5 placed on the plate-shaped arm member 90 is carried into the high-temperature diffusion furnace 9 by the movement of the plate-shaped arm member 90 in the Y-axis direction, and is unloaded when the diffusion process is completed. It has been made to be.

The cassette 60 contains a plurality of wafers 1
1 are stored, and a total of three cassettes 60 are formed as one set. These cassettes 60 are stored on the shelf 8 while being mounted on the cassette tray 6. As shown in FIG.
The cassette tray 6 is stored in such a manner as to bridge a pair of girders 62,62. That is, a space 65 is formed below the cassette tray 6. The vertical dimensions of the space 65 include the vertical dimensions of the tray mounting sections 33 and 43 (including the dimensions of the positioning pins 34 and 44) so that the tray mounting sections 33 and 43 of the hands 3 and 4 can be inserted. ) Is set larger. That is,
The vertical dimension of each of the beams 62, 62
It is set according to the vertical dimension of 3, 43. Each of the above-mentioned beams 62 may be provided on the shelf 8 or may be integrally attached to the cassette tray 6.

The cassette tray 6 is taken out of the shelf 8 by the wafer transfer device 1 as follows. First, the tray mounting portions 33 and 43 of the hands 3 and 4 of the wafer transfer device 1 are moved to the elevation arms 2 and 4 respectively.
From the outside in the positive direction of the Y-axis. This state is selected by rotating the hands 3 and 4 by the first and second rotation mechanisms 7 and 8.

Next, the slider 12 is moved in the Z-axis direction according to the height in the Z-axis direction of the area where the lower space 65 is formed, and the elevation arm 2 is moved in the Z-axis direction. By moving the elevation arm 2 in the positive direction of the X-axis, the tray mounting portions 33 and 43 are inserted into the lower space 65. At this time, the elevation arm 2 is moved so that the positioning pins 34 and 44 formed on the tray mounting portions 33 and 43 correspond to the positioning holes 61 and 61 formed on the cassette tray 6. It is moved in the positive direction of the X-axis to a state shown by a solid line in FIG.

Then, the elevation arm 2 is moved to Z
By moving the positioning pins 34 and 44 into the positioning holes 61 and 61 by moving the cassette tray 6 in the positive direction of the shaft, the cassette tray 6 is raised to a predetermined height. In this state, if the elevation arm 2 is moved in the negative direction of the X axis, the cassette tray 6 is taken out from the shelf.

The cassette tray 6 thus taken out is placed at a predetermined position adjacent to the shelf 8 by moving the elevation arm 2 in the negative direction of the Z axis (FIGS. 4 and 7). reference). Even in this state, a space is formed below the cassette tray 6 by the beams 63 and 63.

In the wafer transfer apparatus 1, the tray mounting sections 33 and 43 are mounted on the elevation arm 2
In the state of protruding from the above, each of the quartz boat suspension supports 32,
Since the portion 42 is hidden under the elevation arm 2, the unused portions (the quartz boat suspensions 32, 42) of the hands 3 and 4 interfere with the quartz boat 5 and the like. You don't need to worry.
For this reason, the cassette tray 6 can be arranged at a position very close to the quartz boat 5, and the space efficiency around the wafer transfer device 1 is improved. Accordingly, the distance by which the elevation arm 2 of the wafer transfer device 1 has to be moved can be reduced, so that the size of the wafer transfer device 1 can be reduced.

As described above, the cassette 60 containing a plurality of wafers 11 is placed on the cassette tray 6, and the wafers 11 contained in these cassettes 60 are placed on the cassette tray 6. It is transferred to a quartz boat 5 arranged adjacently. The transfer of the wafer 11 is performed by a predetermined device (not shown). As this apparatus, for example, an apparatus having a clamp capable of holding the wafer 11 is employed.

As shown in FIG. 7, while the wafers 11 are transferred from the cassette 60 to the quartz boat 5, the hands 3 and 4 are rotated around the Z axis.
It is assumed that the quartz boat suspensions 32 and 42 project from the elevation arm 2 in the negative direction of the X axis. At this time, it is desirable to arrange the quartz boat 5 so that the holding members 30 and 40 of the quartz boat suspension supports 32 and 42 correspond to the handles 50 and 50 of the quartz boat 5. That is, as shown in FIGS. 6 and 7, if the hands 3 and 4 are rotated, the holding portions 30 and 4 are rotated.
The quartz boat 5 is arranged so that 0 is below the handles 50, 50, and if the elevation arm 2 is moved in the positive direction of the Z-axis, the quartz boat 5 is moved by the hands 3, 4. It is desirable to be able to lift.

The quartz boat 5 on which the wafer 11 has been transferred is
The wafer is transferred to the vicinity of the high-temperature diffusion furnace 9 by the wafer transfer device 1, and is placed on a plate-like arm member 90 arranged near the high-temperature diffusion furnace 9. More specifically, as shown in FIGS. 7 and 8, the elevation arm 2 is moved in the positive direction of the Z axis to lift the quartz boat 5, and the elevation arm 2 is moved in the negative direction of the X axis. The quartz boat 5 is placed on the plate-shaped arm member 90 by moving the elevation arm 2 in the negative direction of the Z-axis while moving the elevation arm 2 in the negative direction.

As described above, in the wafer transfer device 1 described above,
Not only the quartz boat 5 but also the cassette 60 can be transported. For this reason, the cassette 60 stored in the shelf 8
Can be automatically performed without having to be taken out manually, and the work efficiency can be improved. In addition, since the cassette 1 can be taken out and transported from the shelf 8 by the device 1 that transports the quartz boat 5 to the vicinity of the high-temperature diffusion furnace 9 or the like, a device for taking out the cassette 60 from the shelf or the like and transporting it is separately provided. Needless to set. For this reason,
In the wafer transfer device 1, the manufacturing cost can be reduced.

The quartz boat 5 placed on the plate arm member 90 is carried into the high-temperature diffusion furnace 9 by the movement of the plate arm member 90, and the wafer 11 is subjected to diffusion processing. On the other hand, while the wafer 11 is being diffused, the empty cassette 60 on which the wafer 11 has been transferred is removed by appropriately moving the elevation arm 2 and an empty quartz boat 5 is newly placed. Then, the cassette 60 accommodated in the shelf 8 is taken out, and the wafer 11 is set in a state where the wafer 11 can be transferred to the quartz boat 5.

The wafer 11 after the diffusion process is
It is transferred from the quartz boat 5 to the cassette 60 and transported to a place where the next step is to be performed. The cassette 60 used at this time may be the previously empty cassette 60 or a new cassette 60 may be prepared.

Of course, the present invention is not limited to the above-described embodiment, and various design changes can be made. For example, each of the hands 3 and 4 is L-shaped in the present embodiment, but is not limited to this, and the quartz boat suspension supports 32 and 4 are not limited thereto.
2 and the tray mounting portions 33 and 43 may be formed. That is, each of the hands 3 and 4 may have a V-shape or another shape.

The mechanism for rotating the hands 3 and 4 can be changed as appropriate. For example, a configuration may be employed in which a predetermined rotational force is transmitted to the hands 3 and 4 to rotate the hands 3 and 4.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an example of a wafer transfer device according to the present invention.

FIG. 2 is a plan view of the wafer transfer device.

FIG. 3 is a perspective view of a main part for describing an operation of the wafer transfer device.

FIG. 4 is a diagram illustrating a layout around the wafer transfer device.

FIG. 5 is a view for explaining a state where a cassette tray is lifted by the wafer transfer device.

FIG. 6 is a view for explaining a state where the quartz boat is lifted by the wafer transfer device.

FIG. 7 is a view for explaining switching of a transfer target by the wafer transfer apparatus, and is a view corresponding to a state viewed in the direction of arrow A in FIG. 4;

FIG. 8 is a perspective view illustrating an example of a conventional wafer transfer device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wafer transfer apparatus 2 Elevation arm 3 1st hand 4 2nd hand 5 Quartz boat 6 Cassette 10 Device main body 11 Wafer 30 Quartz boat hanging support part (of 1st hand) 32 Tray mounting part (of 1st hand) 40 Quartz Boat suspension section (of the second hand) 42 Tray placing section (of the second hand)

Claims (3)

[Claims] An elevation arm projecting from the apparatus main body in the Y-axis direction and movable at least in the X-axis direction and the Z-axis direction, and a constant in the longitudinal direction of the elevation arm. A wafer transfer device comprising: a first hand and a second hand connected to each other at a distance, wherein the first hand and the second hand each include a quartz boat accommodating a plurality of wafers. Each of the quartz boat suspension supports suspended from the hands is provided, and a cassette tray on which a cassette containing a plurality of wafers is placed is bridged between the hands. A wafer transfer device, wherein a tray mounting portion for mounting a wafer is provided. 2. The first hand and the second hand are L
2. The wafer transfer device according to claim 1, wherein the wafer transfer device is formed in a letter shape, a V shape, or a U shape, and is rotatable around the Z axis. 3. The quartz boat suspension of each hand is projected from the elevation arm in the X-axis direction, and the quartz boat is suspended by these quartz boat suspensions, and the wafer is transported together with the quartz boat. And a state in which the tray mounting portions of the respective hands are respectively protruded in the X-axis direction from the elevation arms, and the trays are mounted by these tray mounting portions, and the wafers are transferred together with the trays. 3. The wafer transfer device according to claim 2, wherein the user can select one of the following.