JPH05114641A - Semiconductor wafer cassette carrier - Google Patents

Abstract

PURPOSE:To make it possible to load or unload a semiconductor wafer by means of an automatic robot even when a cassette is subjected to any strain by installing an identification mark to a cassette slot, detecting the mark with a sensor and correcting the position of an arm. CONSTITUTION:There are provided sensors 9a and 9b which detect an identification mark 6 installed near each slot 2b and an identification mark 6 installed integrally on an arm 7. The position of the arm 7 is aligned to the slot 2b equivalent to the identification mark 6 based on the output of the sensors 9a and 9b. Since this construction makes it possible to recognize the positions of the slots with high accuracy, both loading and unloading work can be executed at high speed. It is, therefor, possible to perform normal loading and unloading work even if a strain is produced on a cassette.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer cassette carrier for accommodating a large number of semiconductor wafers at regular intervals.

[0002]

2. Description of the Related Art In the process of manufacturing a semiconductor device, a large number (for example, 25) of semiconductor wafers are temporarily stored in a cassette, and one by one is taken out from the cassette in order by an arm of an automatic robot to a work place for processing. The method has a step of sequentially storing the finished wafers in another cassette.

That is, as shown in FIG.
Has a box shape, one surface of which is released, and the semiconductor wafer is put in and taken out from the released surface. Inside the side wall of the cassette 1, V-shaped grooves 2a and 2b are formed at regular intervals in the vertical direction. The grooves 2a and 2b are formed symmetrically,
When the semiconductor wafer 3 is inserted between the grooves facing each other, the semiconductor wafer 3 is positioned horizontally. Further, the grooves 2a and 2b are set at a vertical interval so that the inserted upper and lower wafers do not come into contact with each other. Further, the cassette 1 has a bottom surface 4 and a ceiling surface 5.

When the semiconductor wafer 3 is inserted (loaded) into the cassette 1 having such a structure, one semiconductor wafer 3 placed on the arm is moved to the groove height by an automatic robot (not shown). Cassette 1 in the combined state
It moves inward and is inserted between the lowermost grooves 2a and 2b. Then, after the insertion is completed, the arm is moved toward you. By advancing this operation one groove at a time, a large number of semiconductor wafers 3 are housed at regular intervals.

On the other hand, when pulling out (unloading) the semiconductor wafer 3, the arm of the automatic robot is moved to the lower surface of the semiconductor wafer 3, and the arm is lifted as it is, so that the semiconductor wafer 3 is placed on the arm. Then, the semiconductor wafer 3 can be pulled out by moving the arm toward you.

The arm position and groove 2 of the automatic robot
Height adjustment with each of a and 2b needs to be performed accurately. Specifically, the bottom surface 4 is recognized, the height of the groove at the lowest stage is grasped with reference to this level, and the arm is moved assuming that the groove increases at a constant interval from this groove.

Incidentally, regarding this kind of technology,
For example, there is JP-A-1-152640.

[0008]

However, in the above-mentioned prior art, since loading and unloading are performed assuming that each groove has an equal pitch with respect to the bottom surface of the cassette, the groove of the cassette and the semiconductor are not processed. It is necessary to prevent the wafer from rubbing and dust, which limits the speed of loading / unloading. Further, the cassette is distorted due to long-term use, the heights of the left and right grooves are displaced, and the automatic robot cannot be used. As a result, the frequency of cassette replacement becomes high, resulting in an increase in cost.

An object of the present invention is to provide a semiconductor wafer cassette carrier which enables loading / unloading of semiconductor wafers by an automatic robot even if the cassette is distorted.

[0010]

In order to achieve the above object, the present invention provides a cassette for continuously forming a groove for supporting a semiconductor wafer at a position facing each other inside a side wall by an arm of an automatic robot. In a semiconductor wafer cassette carrier for horizontally loading / unloading a semiconductor wafer in a groove, an identification mark provided in the vicinity of each groove and a sensor provided integrally with the arm for detecting the mark are provided. The arm is aligned with the groove corresponding to the mark based on the output of the sensor.

[0011]

According to the above-described means, the identification mark provided in the groove for supporting the semiconductor wafer of the cassette is detected by the sensor, and the height of the left and right grooves is displaced due to distortion of the cassette or the like. The position of the arm is corrected. Therefore, since the groove position can be recognized with high accuracy, loading / unloading can be performed at high speed, and loading / unloading can be normally performed even if the cassette is distorted.

[0012]

1 is a perspective view showing an embodiment of a semiconductor wafer cassette carrier according to the present invention (in FIG. 1, only a part of the cassette is shown, and the same as FIG. 2). The same reference numerals are used).

In this embodiment, an identification mark 6 is provided on each of the grooves 2a and 2b so that the actual height of each groove can be recognized. The identification mark 6 may have various shapes. Although an example of a cross-shaped concave portion is shown here, a cross-shaped convex portion, irregularities such as □, ○, and Δ, or a mirror-finished mark may be used. Alternatively, the above shape may be marked with a color, but it is inferior to the uneven shape in that it is easily soiled and the color is peeled off.

In order to recognize the identification mark 6, a pair of sensor arms 8a, 8 is provided from the side of the arm 7 of the automatic robot.
b is projected, and the non-contact type sensors 9a and 9b are attached to the tip thereof.
Is attached. The sensors 9a and 9b are arranged to face the grooves 2a and 2b of the cassette 1 when the semiconductor wafer 3 is loaded / unloaded. As the sensors 9a and 9b, for example, a reflected light type photo sensor, an image sensor (CCD), or the like can be used.

In the above configuration, for example, when loading, the arm 7 is roughly positioned at the height of the groove to be inserted, and the movement of the arm 7 into the cassette 1 is started. In the process of moving the arm 7, the sensors 9a and 9b detect the facing identification mark 6. Based on the state of detection of the identification mark 6, it is determined by a control unit (not shown) whether the arm 7 should be moved up or down from the current position or should be rotated to the right, but to be rotated to the left. Based on this determination result, the arm 7 is driven by a drive unit (not shown) to set the arm 7 at the optimum position. After this, the arm 7 is moved to the back of the cassette 1, and then the arm 7 is slightly lowered.
As a result, the semiconductor wafer 3 is supported by the left and right grooves 2a and 2b. Here, by moving the arm 7 to the front, one loading operation is completed.

[0016]

As described above, according to the present invention, a cassette having a groove for supporting a semiconductor wafer continuously formed at a facing position inside the side wall is loaded horizontally with the arm of an automatic robot. / In the unloading semiconductor wafer cassette carrier,
An identification mark provided in the vicinity of each of the grooves and a sensor that is provided integrally with the arm to detect the mark are provided, and the arm is provided in the groove corresponding to the mark based on the output of the sensor. Since the groove positions can be recognized with high accuracy, loading / unloading can be performed at high speed, and loading / unloading can be performed normally even if the cassette is distorted. Further, the frequency of cassette replacement can be reduced, resulting in cost reduction.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of an embodiment of a semiconductor wafer cassette carrier according to the present invention.

FIG. 2 is a front view showing a conventional semiconductor wafer cassette.

[Explanation of symbols]

 1 cassette 2a, 2b groove 3 semiconductor wafer 6 identification mark 7 arm 8a, 8b sensor arm 9a, 9b sensor

Claims (1)

[Claims] 1. A semiconductor wafer cassette carrier in which a groove for supporting a semiconductor wafer is continuously formed at a position facing each other inside a side wall, and a semiconductor wafer is horizontally loaded / unloaded in the groove by an arm of an automatic robot. An identification mark provided in the vicinity of each of the grooves, and a sensor provided integrally with the arm for detecting the mark, and the groove corresponding to the mark is provided on the basis of the output of the sensor. A semiconductor wafer cassette carrier characterized by aligning the positions of arms.