JPH0729693B2 - Cassette holder - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a set loader for continuously taking out semiconductor wafers from a large number of cassettes or sequentially storing them in a large number of cassettes.

[Conventional technology]

2. Description of the Related Art Conventionally, in a process for manufacturing or processing semiconductor substrates such as wafers, a plurality of wafers are sequentially stored in a cassette during the process or sequentially taken out from the stored cassettes. For this purpose, a cassette loader having a combination of a lifting function and a carrying function is used.

[Problems to be solved by the invention]

However, when using the conventional cassette loader described above for taking out and storing a large number of wafers,
There is a problem that a large number of the cassette loaders are required and the equipment cost increases. In addition, if one cassette loader is used to perform the above operation, time is required for a cassette replacement operation and an operation for returning the elevator to the start position, and this operation time requires a long cycle time, resulting in poor functioning. There is a problem.

The present invention has been made in view of the above circumstances. An object of the present invention is to take out wafers from a large number of cassettes or to store the wafers in the cassettes successively and continuously, and to take out the cassettes. It is an object of the present invention to provide a cassette loader with a low equipment cost, which can continue the taking-out of wafers or the storing of wafers in a cassette during a replacement operation without interruption.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention arranges an angular cassette pedestal in a frame-shaped guide frame so that it can be sequentially fed, leaving a space for one, and the cassette is movably arranged. Conveying means for moving the cradle along the guide frame is attached to the guide frame, and a cassette mounting plate for mounting the cassette is provided on the cassette cradle so that it can be carried in and out along the guide. A plurality of cassette delivery mechanisms for loading or unloading the mounting plates onto or from the cassette pedestal are arranged side by side in the vicinity of the guide frame, and on the cassette mounting plate laid out by the cassette delivery mechanism. Belt conveyor and elevator for sequentially taking out wafers from the cassette of
It is provided so as to face each cassette delivery mechanism.

Further, if necessary, the cassette mounting plate is provided with positioning references capable of respectively positioning with respect to a plurality of types of cassettes.

[Work]

In the cassette loader of the present invention, with respect to the cassettes on the cassette mounting plate carried out by one cassette delivery mechanism, wafers are sequentially taken out or stored by the belt conveyor and the elevator, and other cassette delivery mechanisms and transfer are carried out. By means of the means, the cassette mounting plate with the cassette placed thereon is exchanged between the elevator that faces the cassette delivery mechanism and the cassette pedestal in the frame-shaped guide frame, and a continuous large capacity of wafers is obtained. Take action.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 24.

FIG. 1 is a plan view showing an example of the cassette loader of the present invention. This cassette loader includes a transfer passage 3 formed in a frame shape by the inner guide frame 1 and the outer guide frame 2, and a plurality of movable passages (in the drawing, one movable space 3 is left). 13 cassette holders 4, pullers (conveying means) 5 that are installed at the four corners of the outer guide frame 2 and move the cassette holders 4, and the cassette holders 4. A cassette mounting plate 6 provided so as to be freely carried in and out along the guide portion 40 of the cassette receiving base 4, and a cassette mounting plate 6 installed on the inner guide frame 1 and on the cassette receiving base 4.
Of the two cassette delivery mechanisms 7 that carry out the outer guide frame 2 to the outside of the outer guide frame 2, and the cassette mounting plate 6 mounted on the outer guide frame 2 facing the respective cassette delivery mechanisms 7 Elevator 8 having a letter-shaped lifting plate 8a
And the wafer W from the cassette 9 installed on the cassette mounting plate 6 in the two cutout spaces of the lift plate 8a.
It is composed of a belt conveyor 10 that takes out the wafer W or stores the wafer W in the cassette 9.

The cassette pedestal 4 is formed by stacking three square flat plates 4a (for example, 20 cm on each side), and sandwiching the flat plates 4a with respect to the upper and lower flat plates 4a as shown in FIG. The structure is arranged so as to be shifted downward. The cassette pedestals 4 are connected to each other by a groove portion 4b formed by the three flat plates 4a.
Are connected by loosely fitting the convex portions 4c to each other. Further, the inner and outer guide frames 1 and 2 are formed with convex portions 1a and 2a and groove portions 1b and 2b for loosely fitting in the groove portions 4b and the convex portions 4c of the cassette receiving bases 4, respectively. That is, in FIG. 1, convex portions 1a and 2a are formed on the lower edge of the inner guide frame 1, the right edge and the upper edge of the outer guide frame 2, respectively, and the upper edge of the inner guide frame 1 and the left edge. Grooves 1b and 2b are formed on the edge and the lower edge and the right edge of the outer guide frame 2, respectively. Further, the cassette mounting plate 6 is detachably attached to the guide portion 40 formed on the upper surface of each cassette receiving stand 4.

The cassette mounting plate 6 is formed in a substantially H shape,
A horizontal plate 60 is provided at the center thereof, and a pair of stopper plates 61 having stepped notches 61a at the rear portion (upper portion in FIG. 2).
Are installed respectively. And these horizontal plates
The cassette 9 for storing the wafer is positioned by the notch portion 61a of the both 60 and the stoppers 61. That is, as shown in FIGS. 5 and 6, the cassette 9 used in the present embodiment has a U-shaped front side plate 9a and an H-shaped rear side plate 9a.
9b and a pair of left and right side plates 9 having a groove for housing the wafer W
When the cassette 9 is attached to the cassette mounting plate 6, the rear side plate 9b is placed downward and the lateral plate portion 9d of the rear side plate 9b is attached to the cassette mounting plate 6 as shown in FIG. The lateral plate 60 of the rear plate 9b is aligned with the side surface of the stopper plate 61 side, and the end portion 9e of the rear plate 9b is aligned with the cutout portions 61a of the both stopper plates 61. The cassette 9 is fixed to the cassette mounting plate 6 by fitting the 9d and the end portion 9e between the lateral plate 60 of the cassette mounting plate 6 and the notches 61a of the stopper plates 61, respectively. Further, in this case, each of the stoppers 61 has a stepped shape (see FIG.
Distance between the notches 61a and the notch 61a and the horizontal plate 60
The distance between the 4 inch diameter, 5 inch diameter and 6 inch diameter is 3
Left and right side plates 9c, 9c of each cassette 9 for storing seed wafers W
The distance is set according to the distance and the distance between the end 9e of the rear side plate 9b and the lateral plate 9d, which serves as a positioning reference. Further, each stopper plate 61 is formed with a locking hole 61b for use when the cassette mounting plate 6 is pulled back onto the cassette receiving stand 4. The cassette pedestal 4 and the cassette mounting plate 6 are made of plastic resin having high lubricity, such as ultra-high molecular weight polyethylene.

Further, the puller 5 for transporting the cassette pedestal 4 in the transport path 3 in order is located below the cassette pedestal 4 and pushes the side end surface of the cassette pedestal 4 in one direction (in FIG. 1). It is moved counterclockwise) and is driven by an air cylinder or an electric mechanism (not shown).
Similarly, a puller 5 for moving the cassette pedestal 4 in the reverse direction (clockwise in FIG. 1) is also installed on the outer guide frame 2 (not shown).

Each of the two cassette delivery mechanisms 7 has a push plate 73 fixed to the tip of a piston rod of one air cylinder 71 fixed to the support member 70 and the tips of two guide rods 72. Is. The push plate 73 is a hook-shaped cross section composed of a vertical plate portion and a horizontal plate portion that extends horizontally from the upper portion of the vertical plate portion. The cassette mounting plate 6 is carried out from the cassette receiving table 4. In the case of carrying out, the end surface of the cassette mounting plate 6 is pushed and transferred by the front surface of the vertical plate portion of the pushing plate 73, and when the cassette mounting plate 6 is pulled back onto the cassette 4, the horizontal plate portion of the pushing plate 73 is pushed. The pull rod is projected downward from the lower surface of the cassette, and the pull rod is attached to the cassette mounting plate 6 above.
The engaging holes 61b formed in the respective stoppers 61 are engaged and pulled back. Further, the cassette mounting plate 6
Sliding surface 2c of the outer guide frame 2 corresponding to the loading / unloading passage
Is ground to have the same height as the upper surface of the cassette pedestal 4 and the upper surface of the lift plate 8a of the lift 8 at the start position.

Although not shown, the wafers W taken out from the cassette 9 by the respective belt conveyors 10 are merged to form one wafer.
It is designed to move along the wafer transfer path of a book.
On the contrary, when the wafer W is stored in the cassette 9, the wafer W transferred through the one wafer transfer path is divided into two at the merging point and flows to the cassette 9 side. There is.

Next, the case where the wafer W is stored in each cassette 9 using the cassette loader configured as described above will be described with reference to FIGS. 7 to 24. In these figures, the cassette delivery mechanism 7 (not shown) is arranged so that the cassette 9 is carried out upward. In the figure, ○ indicates a cassette that is being processed or is on standby, ◎ indicates an empty cassette, and ● indicates only the cassette holder. Indicates the processed (stored) cassettes.

First, the initial state shown in FIG. 7, that is, the cassette 9 placed on the cassette mounting plate 6 on the 13 cassette receiving bases 4
With the wafer W not housed therein, as shown in FIG. 8, the first cassette 9-1 is unloaded upward. In this case, in FIG. 1, the lift plate 8a of the lift 8 is shown.
Is the sliding surface of the cassette pedestal 4 and the outer guide frame 2.
It is set at the same height as 2c (this height is referred to as a start position), and the piston rod of the air cylinder 71 of the cassette transfer mechanism 7 (the upper side in FIG. 1) is moved forward to move the piston rod. By pushing the end surface of the cassette mounting plate 6 on the cassette receiving base 4 with the pushing plate 73 fixed to the tip of the cassette supporting plate 4, the cassette mounting plate 6 and the first cassette 9-1 guide the cassette receiving base 4. It is conveyed onto the lift plate 8a of the lift 8 along the portion 40 and the sliding surface 2c of the outer guide frame 2.

Next, in order to store the wafers W sequentially from the uppermost part of the first cassette 9-1, the elevating plate 8a of the elevator 8 is lowered to the lowermost part, and then the wafer W is transferred to the cassette 9-1 by the belt conveyor 10. Each time it is stored in the cassette 9-1
The cassette 9-1 is raised by the elevator 8 by the arrangement interval of the wafers W therein. Thereby, the first cassette 9
Wafers W are stored one after another from the uppermost stage of -1. In parallel with the storing operation of the wafer W, as shown in FIG.
The puller (conveying means) 5 is operated to move the upper three cassette pedestals 4 to the left along the conveying path 3. Subsequently, as shown in FIG. 10, the other cassette delivery mechanism 7 (the lower side in FIG. 1) moves the second cassette 9-2 together with the cassette mounting plate 6 onto the elevator plate 8a of the elevator 8. Transport and wait. After that, as shown in FIG. 11, the upper three cassette pedestals 4 are moved to the right by using the carrying means 5.

Then, when a predetermined wafer W is stored in the first cassette 9-1, as shown in FIG. 12, the cassette delivery mechanism 7 conveys the first cassette 9-1 together with the cassette mounting plate 6. Pull back to passage 3. At the same time, the wafers W are sequentially stored in the second cassette 9-2 that has been on standby by alternately operating the elevator 8 and the belt conveyor 10.

Next, as shown in FIG. 13, after moving the upper three cassette receiving bases 4 to the left, as shown in FIG. It is conveyed together with the mounting plate 6 onto the lift plate 8a of the lift 8 and is kept in standby. Then, as shown in FIG. 15, the upper 3
The individual cassette cradle 4 is moved to the right. And the second
When the storage of the wafer W in the cassette 9-2 is completed,
As shown in FIG. 16, the second cassette 9-2 is returned to the transfer passage 3 side, and the wafer W is stored in the waiting third cassette 9-3. In parallel with this operation, as shown in FIG. 17 to FIG.
By sequentially using the pull tabs 5 installed at the corners, each cassette cradle 4 is moved forward by two counterclockwise. And after being arranged as shown in FIG. 24,
The operations shown in FIG. 9 and subsequent steps are repeated.

As a result, since the wafers W are successively and successively stored in the 13 cassettes 9, a large amount of wafers can be processed smoothly and reliably. Further, when the wafer W is taken out from each cassette 9, the same procedure can be performed. In these cases, two sets of the cassette delivery mechanism 7 and the elevator 8 and the belt conveyor 10 are installed, and the cassette mounting plate 6 is provided between the cassette pedestal 4 in the transport passage 3 and the elevator plate 8a of the elevator 8. 9 and the cassette pedestal 4 is arranged so that the cassette pedestal 4 can be moved forward in the transport passage 3, so that the elevator 8 and the belt conveyor on one side can be moved.
In step 10, while the wafer W is stored in the cassette 9 or the wafer W is taken out from the cassette 9, the cassette delivery mechanism 7 and the transfer means 5 are used to remove the cassette 9 together with the cassette mounting plate 6. The replacement operation can be performed to continue the processing of the wafer W without interruption.
Further, since the cassette mounting plate 6 is set with the positioning reference for mounting the cassette 9 that stores the three types of wafers W having a diameter of 4 inches, a diameter of 5 inches, and a diameter of 6 inches, respectively.
The cassettes 9 of various sizes can be easily placed at a predetermined position on the cassette mounting plate 6, and the cassette mounting plate 6 is carried out to the outside of the transport passage 3 by the cassette delivery mechanism 7 or to the transport passage 3 side. By being able to pull back, regardless of the size and shape of the cassette 9, the loading / unloading operation of the cassette 9 can be performed quickly and reliably.

〔The invention's effect〕

As described above, according to the present invention, the angular cassette holder is movably arranged in the frame-shaped guide frame leaving one space so that the cassette cassette can be sequentially fed, and Conveying means for moving the cassette cradle along the guide frame is attached to the guide frame, and a cassette mounting plate for mounting the cassette is provided on the cassette cradle so as to be able to be carried in and out along the guide. A plurality of cassette delivery mechanisms for loading and unloading the cassette attachment plates on the cassette pedestal are arranged side by side in the vicinity of the guide frame, while the cassette attachment plates delivered by the cassette delivery mechanism. Wafers are taken out from the upper cassette one by one, or a conveyor belt and an elevator for storing wafers in the cassettes are delivered to each cassette. Since they are provided facing each other, wafers are sequentially taken out or stored by the belt conveyor and the elevator for the cassettes on the cassette mounting plate carried out by one cassette delivery mechanism, and the other cassettes are delivered. By the mechanism and the transporting means, the cassette mounting plate is exchanged between the elevator facing the cassette delivery mechanism and the cassette pedestal in the frame-shaped guide frame. Wafers can be taken out or stored in large quantities continuously and simply by moving the cassette mounting plate of a predetermined shape without being affected by the shape or size, and the operation of replacing one cassette During this time, the operation to remove the wafer from the other cassette or store it in the cassette is interrupted. On that can continue without, it is possible to reduce the cost of equipment. Further, if necessary, the cassette mounting plate is provided with positioning references capable of positioning with respect to a plurality of types of cassettes, so that various cassettes can be fixed at predetermined positions on the cassette mounting plate. It has an excellent effect that the cassette can be transferred and the wafer can be smoothly taken in and out from the cassette.

[Brief description of drawings]

1 to 24 show an embodiment of the present invention.
FIG. 1 is a plan view of a cassette loader, FIGS. 2 to 4 show an example of a cassette pedestal, and FIG. 2 is a plan view.
FIG. 3 is a side view, FIG. 4 is a front view, FIGS. 5 and 6 show an example of a cassette, FIG. 5 is a perspective view, FIG. 6 is a sectional view, and FIGS. FIG. 7 shows the procedure for storing the wafers in the cassette. FIG. 7 is an explanatory view of the initial state, FIG. 8 is an explanatory view showing unloading of the first cassette, and FIG. Explanatory diagram showing movement, FIG. 10 is an explanatory diagram showing unloading of the second cassette, FIG. 11 is an illustrative diagram showing movement of the upper cassette pedestal, and FIG. 12 is carrying-in of the first and second cassettes. Explanatory diagram showing unloading, FIG. 13 is an explanatory diagram showing movement of the upper cassette pedestal, FIG. 14 is an explanatory diagram showing unloading of the third cassette, and FIG. 15 is demonstrating movement of the upper cassette pedestal. Explanatory drawing, FIG. 16 is an explanatory drawing showing loading and unloading of the second and third cassettes, FIG. 17 is an explanatory drawing showing movement of the upper cassette pedestal, and FIG. Explanatory view showing the movement of the set pedestal, illustration Figure 19 is showing the movement of the lower cassette receiving table,
FIG. 20 is an explanatory view showing the movement of the cassette cradle on the left side,
Figure is an explanatory diagram showing the movement of the upper cassette pedestal, Figure 22 is an explanatory diagram showing the movement of the right cassette pedestal, Figure 23 is an explanatory diagram showing the movement of the lower cassette pedestal, Figure 24 FIG. 6 is an explanatory view showing the movement of the cassette cradle on the left side. DESCRIPTION OF SYMBOLS 1 ... Inner guide frame, 2 ... Outer guide frame, 3 ... Conveyance passage, 4 ... Cassette receiving stand, 5 ... Puller (conveying means), 6 ... Cassette mounting plate, 7 ... Cassette delivery mechanism , 8 ... elevator, 9 ... cassette, 9-1,
9-2, 9-3 ... Cassette, 10 ... Belt conveyor, W ...
… Wafer, 40… Guide part, 60… Horizontal plate, 61… Clasp, 61a… Notch part.

Claims (2)

[Claims] 1. A frame-shaped guide frame is movably arranged leaving a space for one so that an angular cassette pedestal can be sequentially fed, and the cassette pedestal is arranged along the guide frame. A conveying means for moving is attached to the guide frame, and a cassette mounting plate for mounting the cassette on the cassette receiving base is provided so as to be able to be carried in and out along the guide, and the cassette mounting plate is mounted on the cassette receiving base. A plurality of cassette delivery mechanisms for loading or unloading from the cassette cradle are arranged side by side in the vicinity of the guide frame, while wafers are loaded from the cassette on the cassette mounting plate that is delivered by the cassette delivery mechanism. Belt conveyors and elevators for sequentially picking up or sequentially storing wafers in cassettes face the above cassette transfer mechanisms. Cassette loader, characterized in that provided respectively Te. 2. The cassette loader according to claim 1, wherein the cassette mounting plate has a positioning reference for positioning each of a plurality of types of cassettes.