JPH071785B2 - Stocker device for semiconductor wafer cassette - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a stocker device for three-dimensionally storing a wafer cassette loaded with semiconductor wafers.

[0002]

2. Description of the Related Art Generally, when a semiconductor wafer (hereinafter, simply referred to as a wafer) is processed in various manufacturing processes such as an ion implantation apparatus, a dry etching apparatus or an exposure apparatus, for example, a general wafer such as polypropylene is used. A large number of wafers are loaded into a wafer cassette (hereinafter simply referred to as a cassette) made of a material, transported, stored once in a stocker called a stocker and stored, and then sequentially taken in and out by a stacker crane or the like to perform a predetermined process. Is applied.

Among such manufacturing steps, there is a step of treating the wafer with various chemicals such as removing heavy metal deposits using hydrochloric acid, or removing resist with sulfuric acid hydrogen peroxide. There are many cases.In each case, transfer to a cassette made of special material such as Teflon that has excellent chemical resistance before chemical treatment, and after processing, transfer to a cassette of ordinary general material again and then in process or process Transported in between.

The transfer method will be described. For example, as shown in FIG. 3, the wafer 4 to be processed loaded in the general material cassette 3 carried by the carrier 2 traveling on the track 1 is No. 1 transfer device 5 transfers the wafer to the empty special material cassette 6 on standby, and the entire cassette is chemically processed by the chemical processing device 7. Then, the processed wafer 4A is processed by the second transfer device 8 as a special material cassette. It is transferred from 6 to an empty general material cassette 3 on standby, and again transported by the transport carriage 2 to the next step.

The general material cassette 3 emptied by the transfer by the first transfer device 5 is transferred by the transfer device 9a.
The next processed wafer 4A is received by being sent to the second transfer device 8 via. Further, the special material cassette 6 emptied by the transfer in the second transfer device 8 is transferred to the first transfer device 5 via the transfer device 9b.
In preparation for receiving the next wafer 4 to be processed.

The structure of the transfer device 5 (or 8) will be described. For example, as shown in FIG.
A wafer push-up tool 11 is placed on the side of the general material cassette 3 placed on the above, and a wafer push-up tool is placed on the special material cassette 6.
12 are provided respectively, and the wafer 4 loaded in the general material cassette 3 is pushed up by the wafer push-up tool 11 and then sandwiched by the pair of clamping tools 13 and 14 to move in the arrow D direction and rise. The wafer 4 is placed on the wafer lifting tool 12.

Then, after releasing the clamping tools 13 and 14, the wafer lifting tool 12 is pushed down. As a result, the wafer 4
Can be transferred to the special material cassette 6 (see Japanese Patent Publication No. 61-45381). The processed wafer 4A
In the case of transferring, the operation reverse to the above may be performed.

[0008]

However, in the conventional transfer system as described above, it is necessary to install a transfer device for each manufacturing apparatus, which results in a large installation space, and therefore the area of the clean room. Has to be large, and requires a large number of cassettes made of a special material, resulting in high equipment costs.

Further, the above-mentioned conventional transfer system has the following problems. That is, normally, an identification mark such as a bar code attached for controlling the process is attached to the cassette and is recognized by the mark reading device attached to each process line. The general cassette 3 will be described as an example. As shown in FIG. 5, a U-shaped surface 3a called a U-bar and an H-shaped surface 3b called an H-bar.
Therefore, it is often difficult to attach the identification mark to the surface 3b of the H bar, and it is usually attached to the surface 3a of the U bar.

However, when the transfer device 5 is installed in each manufacturing apparatus to transfer the cassette as described above, the orientation of the cassette changes during the handling, and the orientation of the identification mark also changes. Therefore, it cannot be detected by one mark reading device. Therefore,
Since it is necessary to take countermeasures such as mounting two mark reading devices with different detection directions, or providing a swivel device in each transfer device to align the orientations of the cassettes, the equipment cost is also high. There's a problem.

The present invention has been made to solve the above-mentioned conventional problems, and is a semiconductor wafer in which a transfer device and a stocker are integrally configured, and a swivel device is incorporated in the transfer device. The purpose is to provide a cassette stocker.

[0012]

SUMMARY OF THE INVENTION The present invention is a stocker device for three-dimensionally storing a wafer cassette into which a large number of semiconductor wafers are loaded, and a storage shelf for storing a group of a plurality of wafer cassettes, and this storage. A first stocker composed of a stacker crane for loading and unloading wafer cassettes from a shelf and transporting the wafer cassette to a predetermined position, and a storage shelf provided adjacent to the first stocker for accommodating a plurality of different groups of wafer cassettes. Provided between the second stocker and the first stocker, which is a stacker crane for loading and unloading the wafer cassette from the storage shelf and transporting the wafer cassette to a predetermined position. A transfer device for transferring a semiconductor wafer loaded in the stored wafer cassette to an empty wafer cassette stored in the other stocker, Is attached to the transfer sorter stocker apparatus for a semiconductor wafer cassette, wherein a turning device for changing the orientation of the wafer cassette, in that they are composed of.

[0013]

According to the present invention, the first stocker for accommodating a plurality of groups of cassettes and the stocker for accommodating a plurality of different groups of cassettes are connected in series, and a transfer device having a swiveling device therebetween is provided. Since the wafers are arranged, it is possible to collectively transfer wafers from one group of cassettes to another group of cassettes or from another group of cassettes to one group of cassettes. The identification marks can be accurately detected by aligning the marks in a predetermined direction.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a plan view showing an embodiment of the present invention. In the drawings, the same members as those in the conventional example are designated by the same reference numerals and the description thereof will be omitted. In the figure, reference numeral 15 is a first stocker, which is a storage shelf 16 for accommodating a cassette 3 made of a general material used in a normal process, and a cassette 3 which is taken in and out of the storage shelf 16 and travels on a track 17 to a predetermined position. The stacker crane 18 conveys the stacker crane to a position.

Reference numeral 19 denotes a second stocker, which is a storage shelf 20 for accommodating a cassette 6 made of a special material having excellent chemical resistance, and a cassette 6 which is taken in and out of the storage shelf 20 and runs on a track 21 to a predetermined position. The stacker crane 22 transports the stacker to a position, and is provided adjacent to the first stocker 15. Reference numeral 23 is a transfer device as shown in FIG. 4, which is installed between the first stocker 15 and the second stocker 19 described above. Reference numeral 24 is a turning device for the cassette 3 made of a general material, which is attached to the transfer device 23. As shown in FIG. 2 in an enlarged view, the cassette mounting table 25 and a motor 26 for freely rotating the cassette mounting table 25 are provided. Composed. Reference numeral 27 is a turning device for the cassette 6 made of a special material, which is also attached to the transfer device 23, and is composed of a cassette mounting table 28 and a motor 29.

[0016] A stocker 1 configured by connecting in this way
An operation when the wafer 4 is processed by the chemical processing apparatus 7 as shown in FIG. First, in the first stocker 15, one of the cassettes 3 made of a general material loaded with the wafers 4 to be processed is pulled out from the storage rack 16 by the stacker crane 18 and conveyed to the transfer device 23, where one cassette is loaded. Place it on the table 25.
Then, in the second stocker 19, one of the empty cassettes 6 of the special material is pulled out from the storage shelf 20 by the stacker crane 22 and conveyed to the transfer device 23, and placed on the other cassette mounting table 28. Therefore, the cassette mounting table 28 on which the cassette 6 of the special material is placed is rotated 180 ° by the motor 29 to change the direction of the cassette 6 of the special material to the opposite direction. Then, the transfer device 23 operates to transfer the wafer 4 to be processed, which is loaded in the cassette 3 of the general material, to the cassette 6 of the special material. Further, a cassette mounting table 28 on which the special material cassette 6 is mounted
Motor 29 in the opposite direction from the step.
Turn 180 ° to return the orientation of the special material cassette 6 to the step state. The special material cassette 6 loaded with the wafer 4 to be processed is transferred to the chemical processing device 7 by using a transfer device (not shown) in the process to perform the chemical processing. At this time, the cassette 3 made of a general material stands by on the one cassette mounting table 25 of the transfer device 23 in an empty state. The cassette 6 of the special material loaded with the processed wafers 4A is carried into the stocker 19 again by the transfer device in the process, and the stacker crane is installed.
The other cassette mounting table 28 of the transfer device 23 via 22
Then, the motor 29 of the revolving device 27 turns it 180 ° to change the direction of the cassette 6 made of a special material. When the transfer device 23 operates in the opposite manner to the first operation, the processed wafers 4A loaded in the special material cassette 6 are transferred to the general material cassette 3 in the standby state. The stacker crane 18 sends the cassette 3 made of a general material loaded with the processed wafers 4A to the next processing step. The emptied special material cassette 6 is then stored and stored in a predetermined position on the storage rack 20 by the stacker crane 22.

In the above embodiment, the turning device
Although it has been described that the direction of the special material cassette 6 is changed by using 27, it is needless to say that the direction of the special material cassette 6 can be similarly changed by using the other turning device 24. The turning device attached to the transfer device 23 may be either one. In the above embodiment, the wafer 4 is transferred from the cassette 3 made of a general material to the cassette 6 made of a special material or the cassette 6 made of a special material.
However, the present invention is not limited to this. For example, when the cassette used in the process before Al wiring and the cassette used in the Al wiring process are separately used. As described above, it goes without saying that the present invention can be easily applied to transfer between cassette groups of the same material.

[0018]

As described above, according to the present invention,
Since the stocker for accommodating the cassette of one group and the stocker for accommodating the cassette of another group are connected in series, and the transfer device is arranged so as to have the swivel device therebetween, the wafers from the cassette of one group to the cassette of another group are arranged. Transfer to a cassette or from another group of cassettes to one group of cassettes can be performed collectively and at the same time, the identification mark can be accurately detected by aligning the cassettes in a predetermined direction. As a result, it is possible to save the installation space and the area of the clean room, ensure the process control of the cassette, and save the equipment cost.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is an enlarged front view showing the outline of the configuration of the transfer device.

FIG. 3 is an explanatory diagram of an outline of a conventional transfer method.

FIG. 4 is a schematic diagram of a conventional transfer device.

FIG. 5 is a perspective view of a cassette.

[Explanation of symbols]

 3 General material cassette 4 Wafer 6 Special material cassette 15 1st stocker 16, 20 Storage rack 18, 22 Stacker crane 19 2nd stocker 23 Transfer device 24, 27 Swivel device.

Claims (1)

[Claims] 1. A stocker device for three-dimensionally storing a wafer cassette into which a large number of semiconductor wafers are loaded, and a storage shelf for storing a group of wafer cassettes composed of a plurality of storage cassettes.
Storage for storing a wafer cassette of a first group, which comprises a stacker crane for loading and unloading wafer cassettes from the storage shelf and transporting the wafer cassette to a predetermined position, and a wafer cassette of a plurality of different groups, which is provided adjacent to the first stocker. A second stocker composed of a shelf and a stacker crane for loading and unloading the wafer cassette from the storage shelf and transporting the wafer cassette to a predetermined position; and a second stocker provided between the second stocker and the first stocker. A transfer device for transferring a semiconductor wafer loaded in a wafer cassette stored in a stocker to an empty wafer cassette stored in the other stocker, and a swivel device attached to the transfer device for changing the orientation of the wafer cassette. And a stocker device for a semiconductor wafer cassette.