JPH0728108U - Defect detection master basket - Google Patents

Abstract

(57) [Abstract] [Purpose] To correct the error and find the cause of failure in the automatic transfer of semiconductor wafers by the automatic transfer machine in a short time. [Structure] Rib pieces 11A, 1 for supporting a semiconductor wafer 6
The master basket 1 for defect detection is provided with 2A, 12B and 13A. The ribs 11A are formed by slightly displacing the ribs 11A from the equidistant positions and gradually increasing the amount of deviation, and the position deviation is determined depending on which rib piece 11A is aligned to determine the position deviation. Fine-tune the error. Inclining each rib piece 12A, 12B, 13A back and forth, left and right,
In addition, the degree of inclination is gradually increased to form the inclination amount, and the amount of inclination is determined depending on which rib piece 12A, 12B, 13A is aligned, and the error is finely adjusted according to this.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is a master basket for defect detection that detects and corrects the cause of transfer defects when a semiconductor wafer is automatically taken in and out from a basket containing a plurality of semiconductor wafers by an automatic transfer machine. Regarding

[0002]

[Prior art]

 Usually, a plurality of semiconductor wafers are simultaneously stored in a basket while being supported by a supporting rib provided inside the basket. When a semiconductor wafer is processed, it is moved to each processing step along with the basket, and each semiconductor wafer is automatically taken out from the basket one by one by an automatic transfer machine, and various kinds of processing are performed. After processing, it is automatically stored in the basket again by the automatic transfer machine.

The taking-out and storing operations by the automatic transfer machine are performed as follows.

First, the basket is moved to the processing step and installed on a predetermined installation table. At this time, the semiconductor wafer stored inside the basket becomes horizontal. As a result, the semiconductor wafers are stacked one on top of the other with a constant gap between each pitch.

In this state, the tongue-shaped thin plate (see FIG. 5) of the automatic transfer machine is inserted into the pitch gap between the semiconductor wafers, and the semiconductor wafers are taken out. That is, the tongue-shaped thin plates inserted in the pitch gaps between the semiconductor wafers are slightly raised to lift the semiconductor wafers, and the semiconductor wafers are taken out while keeping the horizontal state. When processing is completed, insert the semiconductor wafer placed on the tongue-shaped thin plate into the basket, lower the tongue-shaped thin plate slightly and place the semiconductor wafer on the supporting rib, and remove the tongue-shaped thin plate. .

High precision is required for the transfer operation of the semiconductor wafer by the above automatic transfer machine. Therefore, if there is an error in each step, it is necessary to eliminate the error. This error is resolved by the following method. In each processing step that causes an error, a basket containing a plurality of semiconductor wafers is actually installed on the installation table. The semiconductor wafers stored in this basket are actually transferred by an automatic transfer machine, and the error is finely adjusted. Specifically, the semiconductor wafer is actually transferred from the basket by the automatic transfer machine and it is confirmed whether or not transfer failure occurs. If a transfer failure occurs, adjust the automatic transfer machine and the installation base, and adjust the alignment between the automatic transfer machine and the installation base. After this adjustment, the semiconductor wafer is transferred again by the automatic transfer machine, and it is confirmed whether transfer failure occurs. This process is repeated to correct the error. This correction is performed in each processing step.

The errors that occur at this time include an error in the vertical displacement and an error in the inclination in the front-rear and left-right directions. These errors are caused by defects in the manufacturing accuracy of the basket, the automatic transfer machine and the installation table, the alignment accuracy of the automatic transfer machine and the installation table, and the like. These errors are complexly entangled and cause transfer failure in the automatic transfer machine.

[0008]

[Problems to be solved by the device]

 However, the conventional error correction means as described above has the following problems.

The error that causes defects is caused by complex entanglement of defects such as the accuracy of the automatic transfer machine and the installation table, the alignment accuracy of the automatic transfer machine and the installation table, and the manufacturing accuracy of the basket itself. Is also involved. Therefore, even if the error is corrected in the normal basket in one process, the transfer failure may occur in the other basket.

Further, since these errors are intertwined in a complex manner, it may not be clear whether or not a similar phenomenon to the error in one process is caused in another process due to the same cause. Therefore, it takes time to find the cause of the defect.

As a result, there is a problem that a large amount of time is required if the number of processes that need to be corrected increases.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a defect detection master basket capable of correcting an error and finding a cause of a defect in a short time.

[0013]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, a defect detecting master basket according to a first aspect of the present invention is a defect detecting master basket having a plurality of rib pieces arranged in parallel to face each other to support a semiconductor wafer in multiple stages. In the master basket for use, the rib pieces are formed by slightly shifting the disposition intervals of the rib pieces from the equidistant positions and gradually increasing the deviation amount.

According to a second aspect of the master basket for defect detection, a pair of rib pieces provided to face each other to horizontally support the semiconductor wafer is supported by the pair of rib pieces. It is characterized in that the semiconductor wafer is tilted in the front-rear direction and the left-right direction so that it is tilted in the front-rear direction and in the left-right direction, and the degree of inclination of the rib pieces provided in multiple stages is gradually increased.

[0015]

[Action]

 According to the first invention, the amount of positional deviation in the vertical direction from the reference rib piece can be known from which rib piece is the reference rib piece. For this reason, the automatic transfer machine attempts to move the semiconductor wafer into and out of the master basket for defect detection, and the position of the rib at the aligned position deviates in the vertical direction depending on the number of the rib from the reference rib. Know the amount and make fine adjustments accordingly.

In the second invention, the deviation amount of the inclination in the front-rear, left-right direction from the reference rib piece can be known from the rib piece serving as the reference rib piece. For this reason, the amount of deviation in the front, rear, left, and right directions of the rib piece at the position aligned by the loading and unloading of the semiconductor wafer with the automatic transfer machine can be known from the reference rib piece, and it can be adjusted accordingly. Fine-tune.

[0017]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

The defect detection master basket according to the present embodiment is preliminarily formed with various kinds of grooves corresponding to the above-mentioned various errors, and when the semiconductor wafer is transferred by the automatic transfer machine, it is accurate which groove is used. This is a basket that allows you to determine the cause of the error depending on whether or not it was transferred to. There are errors in vertical displacement and errors in inclination in the front-rear, left-right directions, etc. as this error. However, in order to offset the error, the semiconductor wafer supported by the basket is positively offset. To mold.

A specific configuration of the defect detection master basket 1 will be described below with reference to FIGS. 1 to 5.

As shown in FIG. 4, the defect-detecting master basket 1 includes a housing 2 of which one side serves as an inlet / outlet 2 A of the semiconductor wafer 6 and two side plates 3 and 4 of the housing 2 facing each other. The support ribs 5 are formed in multiple stages on the inner surface, and each of the plurality of semiconductor wafers 6 is substantially parallel to each other. The one side wall 2B of the housing 2 is brought into contact with the installation table in a state where the housing 2 is placed vertically (state of FIG. 4) so that the semiconductor wafer 6 inserted therein is supported substantially horizontally. It has become.

Each supporting rib 5 is composed of a large number of rib pieces 5 A provided on the side plates 3 and 4 in a state of being arranged at a predetermined interval. The rib piece 5A is formed into a thin taper shape in cross section. Each rib piece 5A is formed so that the semiconductor wafer 6 supported thereby is displaced vertically, forward and backward, and laterally.

As for vertical error, left and right symmetrical rib pieces 11A, 11A are formed as shown in FIG. That is, the intervals between the rib pieces 11A are formed by slightly shifting from the equidistant positions. Further, the amount of deviation is set to be gradually larger than the rib pieces 20 at regular intervals such as intervals a, b, and c. This deviation amount is set so as to change at a constant rate, and it becomes possible to know how many rib pieces 11A deviate from the reference rib pieces 11B, 11B and how many μm deviates from the corresponding normal rib pieces 20. ing. The rib pieces 11A and 11A are formed so as to be vertically displaced at the same rate with respect to the reference rib pieces 11B and 11B.

For the left-right error, rib pieces 12A and 12B are formed as shown in FIG. Of the supporting ribs 12 arranged to face each other, one rib piece 12A (right side in the figure) is formed at equal intervals, and the other rib piece 12B (left side in the figure). Are formed by slightly shifting like the rib pieces 5A in FIG. The deviation amount of the rib pieces 12B is set to be gradually increased, like the intervals a, b, and c in FIG. As a result, with respect to the reference semiconductor wafer 6 placed on the reference rib piece 12C in FIG. 2, the inclination in the left-right direction (the inclination in the right direction in FIG. 2) gradually increases as the distance from the reference semiconductor wafer 6 increases. Is set to. Further, the inclination amount is set so that it can be seen how many rib pieces 12A and 12B are inclined from the horizontal state, as in the case of the vertical error. The rib pieces 12A and 12B are formed so as to be inclined centering around the reference rib piece 12C while changing the degree of inclination in the same proportion in the vertical direction and in the same inclination direction. Further, a rib piece that is inclined to the left as opposed to FIG.

For the front-back error, a rib piece 13A is formed as shown in FIG. It should be noted that FIG. 3 is a schematic view schematically showing the arrangement of the rib pieces 13A. As shown in the drawing, each rib piece 13A is arranged so as to gradually incline in the front-rear direction at a larger angle as it goes away from the rib piece 13B serving as a reference. As a result, as the distance from the reference semiconductor wafer 6 supported by the reference rib piece 13B increases (as it is supported by the upper rib piece 13A), the inclination in the front-back direction with respect to the reference semiconductor wafer 6 increases. . Further, the amount of inclination is such that the number of rib pieces 13A inclined from the horizontal rib piece 13B serving as a reference can be understood as in the case of the vertical error. The rib piece 13A is formed so as to be inclined centering around the reference rib piece 13B while changing the degree of inclination in the same proportion and in the same inclination direction. Also, rib pieces inclined in the opposite direction are formed in the same manner as described above. In addition, these are formed bilaterally.

The defect detection master basket 1 configured as described above is molded with high precision from synthetic resin, metal or the like. A normal basket has a 3/16 inch pitch or a 1/4 inch pitch and is configured to accommodate 25 semiconductor wafers 6. Therefore, the rib pieces 11A for the vertical error, the rib pieces 12A, 12B for the horizontal error, and the rib piece 13A for the front-back error may be integrated into one defect detection master basket 1, and two or three defect detections may be performed. The master basket 1 may be separately incorporated. Also, these may be combined and tilted to the left or right or front and back while shifting in the vertical direction, or tilted to the front and back while tilted to the left and right.

Next, detection and correction of an error using the defect detection master basket 1 having the above-described configuration will be described.

In each processing step, the defect detection master basket 1 is installed on each installation table (not shown), and the tongue-shaped thin plate 15 (see FIG. 5) of the automatic transfer machine (not shown) is used to semi-finish the process. The conductor wafer 6 is actually transferred. At this time, it is measured whether the semiconductor wafer 6 supported by the tongue-shaped thin plate 15 can be accurately transferred by the rib pieces 11A, 12A, 12B, 13A from the reference rib pieces 11B, 12C, 13B. From this, it is possible to know how many μm or how many deviations have been made in the up, down, front, rear, left and right directions. Fine-tune each part according to this result. At this time, since the defect detecting master basket 1 is formed with high accuracy, it is not necessary to consider the error of the master basket 1 itself.

As described above, by actually transferring the semiconductor wafer 6 using the defect detecting master basket 1, the cause of the defect can be easily and quickly found. As a result, the error can be easily corrected.

The displacement of the semiconductor wafer 6 in the front-rear direction and the left-right direction is performed by adjusting the installation position of the basket itself or the moving position of the tongue-shaped thin plate 15 of the automatic transfer machine.

[0030]

[Effect of device]

 As described in detail above, according to the master basket for defect detection of the present invention, by actually transferring a semiconductor wafer using this basket, the cause of the defect can be easily and quickly found. The error can be easily corrected.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts showing an arrangement state of rib pieces corresponding to vertical errors of a defect detection master basket according to the present invention.

FIG. 2 is a cross-sectional view of a main part showing a disposition state of rib pieces corresponding to a left-right error of the defect detection master basket according to the present invention.

FIG. 3 is a schematic view showing an arrangement state of rib pieces corresponding to front-back errors of the defect detection master basket according to the present invention.

FIG. 4 is a perspective view showing a master basket for defect detection according to the present invention.

FIG. 5 is a plan view showing a tongue-shaped thin plate of the automatic transfer machine.

[Explanation of symbols]

1 ... Defect detection master basket, 3, 4 ... Side plate, 6 ...
Semiconductor wafer, 11A, 12A, 12B, 13A ... Rib piece, 11B, 12C, 13B ... Rib piece serving as a reference.

Claims (2)

[Scope of utility model registration request] 1. A defect detection master basket comprising a plurality of ribs arranged in parallel to face each other and supporting ribs for supporting a semiconductor wafer in multiple stages. A master basket for defect detection, characterized in that the master basket is formed by shifting the distance from the distance position little by little and gradually increasing the amount of deviation. 2. A defect detection master basket comprising parallel supporting ribs, each having a plurality of rib pieces arranged thereon to support a semiconductor wafer in multiple stages, and a relative portion for supporting the semiconductor wafer horizontally. Inclination of the rib pieces provided facing each other in a front-rear direction and in a left-right direction so that the semiconductor wafer supported by the rib pieces forming the pair inclines in the front-rear direction and the left-right direction, and the inclination of the rib pieces provided in multiple stages A master basket for defect detection, which is formed by gradually increasing the degree of