JPH04226050A - Stocker for semiconductor wafer cassette - Google Patents

Abstract

PURPOSE:To improve a stocker for vertically storing wafer cassette charged with wafers. CONSTITUTION:There are provided a first stocker 15 for storing ordinary wafer cassettes 3 and a second stocker 19 for storing special wafer cassettes 6. A transfer device 23 having a swivel mechanism is provided between the first and second stockers. This constitution makes it easy to transfer wafer cassettes from one stocker to the other.

Description

[Detailed description of the invention]

0001

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

0002

[Prior Art] Normally, when semiconductor wafers (hereinafter simply referred to as wafers) are processed in various manufacturing processes such as ion implantation equipment, dry etching equipment, or exposure equipment, they are processed using common materials such as polypropylene. A large number of wafers are loaded into a wafer cassette (hereinafter simply referred to as a cassette) made of the same material and transported, stored in a storage warehouse called a stocker, and then sequentially taken out and taken out using a stacker crane etc. for predetermined processing. This is what we do.

[0003] Among these manufacturing processes, there are steps in which the wafer is treated using various chemicals, such as removing heavy metal deposits using hydrochloric acid or removing resist using sulfuric acid and hydrogen peroxide. There are many cases, and in each case, the chemical treatment is performed after transferring to a cassette made of a special material with excellent chemical resistance, such as Teflon, and after the treatment is completed, the process is transferred again to a cassette made of a normal general material. transported between.

[0004] Here, to explain the transfer method, for example, as shown in FIG. The wafer 4A is transferred to a waiting empty special material cassette 6 by the first transfer device 5 and treated with chemicals in the chemical treatment device 7, and then the processed wafer 4A is transferred to the special material cassette by the second transfer device 8. 6 to an empty general material cassette 3 on standby, and transported again to the next process by the transport vehicle 2.

[0005] The general material cassette 3 emptied by the transfer in the first transfer device 5 is transferred to the transfer device 9a.
The next processed wafer 4A is received by being sent to the second transfer device 8 via the transfer device 8. In addition, 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.
The wafer 4 is sent to the wafer 4 in preparation for receiving the next wafer 4 to be processed.

Further, to explain the configuration of the transfer device 5 (or 8), for example, as shown in FIG.
A wafer pushing tool 11 is provided on the side of the general material cassette 3 placed on the cassette 3 of general material, and a wafer pushing tool 12 is provided on the special material cassette 6. The wafer 4 is pushed up by the push-up tool 11, then moved in the direction of arrow D while being held between a pair of clamping tools 13 and 14, and placed on the wafer push-up tool 12 which is being raised.

After releasing the clamping tools 13 and 14, the wafer pushing tool 12 is pushed down. by this,
The wafer 4 can be transferred to a cassette 6 made of a special material (see Japanese Patent Publication No. 45381/1983). In addition, when transferring the wafer 4A after processing, the operation described above may be reversed.

[0008]

[Problems to be Solved by the Invention] However, in the conventional transfer method as described above, it is necessary to install a transfer device for each manufacturing device, which requires a large installation space, which reduces the area of the clean room. This method has drawbacks such as a large number of cassettes, a large number of cassettes made of special materials, and increased equipment costs.

[0009] Furthermore, the above-mentioned conventional transfer method also includes the following problems. In other words, normally, an identification mark such as a bar code is attached to the cassette for process control, and it is recognized by a mark reading device installed at each process line. Taking a general cassette 3 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 affix an identification mark to the surface 3b of the H bar, and the identification mark is usually affixed to the surface 3a of the U bar.

However, when the transfer device 5 is installed in each manufacturing device to transfer cassettes as described above, the orientation of the cassette changes during handling, and the orientation of the identification mark also changes. Therefore, a single mark reading device cannot detect the mark. Therefore,
It is necessary to take countermeasures such as installing two mark reading devices with different detection directions, or installing a rotation device on each transfer device to align the orientation of the cassettes, resulting in high equipment costs. There's a problem.

The present invention has been made to solve the conventional problems as described above, and provides a semiconductor wafer transfer device in which a transfer device and a stocker are integrally constructed, and a rotation device is built into the transfer device. The purpose is to provide a cassette stocker.

0012

[Means for Solving the Problems] The present invention is a stocker device that three-dimensionally stores wafer cassettes loaded with a large number of semiconductor wafers. a first stocker comprising a stacker crane for loading and unloading wafer cassettes from the shelf and transporting them to a predetermined position; a storage shelf provided adjacent to the first stocker for storing another group of wafer cassettes; , a second stocker comprising a stacker crane that takes wafer cassettes in and out of the storage shelf and transports them to a predetermined position; and a second stocker that is provided between the second stocker and the first stocker and that a transfer device that transfers a semiconductor wafer loaded in a stored wafer cassette to an empty wafer cassette stored in the other stocker; a rotation device that is attached to the transfer device and changes the orientation of the wafer cassette; 1 is a stocker device for semiconductor wafer cassettes characterized by comprising:

[0013]

[Function] According to the present invention, a transfer device is provided in which a first stocker for storing a plurality of groups of cassettes and a stocker for storing a plurality of different groups of cassettes are connected in series, and a rotating device is provided between them. wafers can be transferred from one group of cassettes to another group of cassettes, or from another group of cassettes to one group of cassettes, all at once. By aligning the marks in a predetermined direction, the identification mark can be detected accurately.

[0014]

Embodiments Below, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a plan view showing one embodiment of the present invention. In addition, in the drawings, the same members as in the conventional example are given the same reference numerals, and the description thereof will be omitted. In the figure, 15
is a first stocker, which includes a storage shelf 16 that stores cassettes 3 made of general materials used in normal processes, and a storage shelf 16 in which the cassettes 3 are taken in and taken out and run on a track 17 to be transported to a predetermined position. It consists of a stacker crane 18.

Reference numeral 19 denotes a second stocker, which includes a storage shelf 20 for storing cassettes 6 made of a special material with excellent chemical resistance, and a storage shelf 20 for storing cassettes 6 in and out of the storage shelf 20.
A stacker crane 2 that travels over 1 and transports it to a predetermined position.
2, and is provided adjacent to the first stocker 15. Reference numeral 23 denotes a transfer device as shown in FIG.
will be installed between. Reference numeral 24 denotes a turning device for the cassette 3 made of a general material attached to the transfer device 23, and as shown in an enlarged view in FIG. configured. 27
Similarly, a cassette 6 rotating device made of a special material is attached to the transfer device 23, and is composed of a cassette mounting table 28 and a motor 29.

[0016] The stockers 1 configured in series in this manner
5 and 19, the operation when processing the wafer 4 in the chemical processing apparatus 7 as shown in FIG. 3 will be described below. ■ First, in the first stocker 15, one of the cassettes 3 made of general material loaded with wafers 4 to be processed is pulled out from the storage shelf 16 by the stacker crane 18, transported to the transfer device 23, and one of the cassettes 3 is loaded with wafers 4 to be processed. Mounting table 2
Put it on 5. ■ Next, in the second stocker 19, one of the empty special material cassettes 6 is pulled out from the storage shelf 20 by the stacker crane 22, transported to the transfer device 23, and placed on the other cassette mounting table 28. . (2) Therefore, the cassette mounting table 28 on which the cassette 6 made of special material is placed is rotated by 180 degrees by the motor 29 to change the orientation of the cassette 6 made of special material to the opposite direction. (2) Then, the transfer device 23 operates to transfer the wafers 4 to be processed loaded in the cassette 3 made of a general material to the cassette 6 made of a special material. ■Furthermore, the cassette mounting table 28 on which the special material cassette 6 is placed is moved by the motor 29 in the opposite direction to step ■180.
Rotate the special material cassette 6 to return it to the state in step (2). ■ Special material cassette 6 loaded with wafers 4 to be processed using an in-process transport device (not shown)
is transported to the chemical treatment device 7 and subjected to chemical treatment. At this time, an empty cassette 3 made of a general material is waiting on one cassette mounting table 25 of the transfer device 23. ■ The cassette 6 made of a special material loaded with the processed wafers 4A is carried into the stocker 19 again by the transport device within the process, and sent to the other cassette mounting table 28 of the transfer device 23 via the stacker crane 22. The direction of the special material cassette 6 is changed by rotating it by 180 degrees by the motor 29 of the rotating device 27. ■ By performing the reverse operation of the transfer device 23, the processed wafers 4A loaded in the special material cassette 6 are transferred to the general material cassette 3 in a waiting state.
Transfer to. (2) The stacker crane 18 transports the cassette 3 made of a general material loaded with the processed wafers 4A to the next processing step. Note that the empty special material cassette 6 is then moved to the storage shelf 20 by the stacker crane 22.
It is stored and stored in a designated location.

In the above-mentioned embodiment, the orientation of the cassette 6 made of special material is changed using the rotating device 27, but the direction of the cassette 6 made of special material can be changed in the same way by using the other rotating device 24. Needless to say, the direction can be changed, and either one of the rotating devices may be attached to the transfer device 23. Furthermore, in the above embodiments, the transfer of the wafers 4 was described as being carried out from the cassette 3 made of a general material to the cassette 6 made of a special material, or from the cassette 6 made of a special material to the cassette 3 made of a general material. The present invention is not limited to this, and can be easily transferred between groups of cassettes made of the same material, for example, when cassettes used in the process before Al wiring and cassettes used in the Al wiring process are used separately. Needless to say, it can be applied to

[0018]

[Effects of the Invention] As explained above, according to the present invention,
A stocker for storing one group of cassettes and a stocker for storing another group of cassettes are arranged in two, and a transfer device with a rotation device is placed between them, so that wafers can be transferred from one group of cassettes to another group. It is possible to transfer to a cassette or from another group of cassettes to a group of cassettes in one batch, and at the same time, by aligning the orientation of the cassettes in a predetermined direction, identification marks can be detected accurately. This makes it possible to save installation space and clean room area, ensure cassette process control, and further reduce equipment costs.

[Brief explanation of the drawing]

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 overview of a conventional transfer method.

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

FIG. 5 is a perspective view of the cassette.

[Explanation of symbols]

3 General material cassette 4 Wafer 6 Special material cassette 15 First stocker 16, 20 Storage shelf 18, 22 Stacker crane 19 Second stocker 23　Transfer device 24, 27 Swivel device.

Claims (1)

[Claims] 1. A stocker device for three-dimensionally storing wafer cassettes loaded with a large number of semiconductor wafers, comprising a storage shelf for storing a group of wafer cassettes, and a storage shelf for loading and unloading wafer cassettes from the storage shelf. A first stocker consisting of a stacker crane for transporting wafers to a predetermined position; a storage shelf provided adjacent to the first stocker for storing another group of wafer cassettes; and a storage shelf for storing wafer cassettes from the storage shelf. A second stocker consisting of a stacker crane for loading and unloading wafers and transporting them to a predetermined position, and a second stocker provided between the second stocker and the first stocker to load wafers into wafer cassettes stored in one stocker. The present invention is characterized in that it is comprised of a transfer device that transfers the semiconductor wafers stored in the other stocker to an empty wafer cassette stored in the other stocker, and a rotation device that is attached to the transfer device and changes the orientation of the wafer cassette. Stocker device for semiconductor wafer cassettes.