KR100810435B1 - Centering guide with wafer slip prevention means - Google Patents

Abstract

The present invention relates to a wafer inspection apparatus, and more particularly, to a centering guide for centering a wafer prior to alignment in a pre-align table of the wafer inspection apparatus.

Accordingly, the present invention is a wafer inspection equipment including a cassette carrier, a robot arm, an exchange chamber and a gun chamber, and a pre-alignment table is provided in the exchange chamber, wherein the pre-alignment table in the exchange chamber is disposed opposite to each other. Left and right guide blocks which can move in different directions, and each opposing surface is concave and curved to conform to the edge shape of the wafer; And a wafer seating end attached to a lower end of each of the left and right guide blocks to protrude more toward the preliminary alignment table than a concave opposing surface of each of the left and right guide blocks, and each wafer attached to the left and right guide blocks. And a wafer slip prevention means attached to an opposite surface of the seating end and configured to include a slip prevention jaw formed to be inclined downward toward the preliminary alignment table to hold the center of the wafer placed on the preliminary alignment table. Provide a centering guide.

Wafer, Slip, Centering Guide, Inspection Equipment

Description

CENTERING GUIDE HAVING MEANS FOR PREVENTING WAFER FROM SLIPPING}

1 is a perspective view showing a centering guide having a wafer slip prevention means according to an embodiment of the present invention.

2 is a front view showing a right guide block of the centering guide according to an embodiment of the present invention.

3 is a plan view showing a right guide block of the centering guide according to an embodiment of the present invention.

Figure 4 is a cross-sectional view for explaining the operation of the centering guide according to an embodiment of the present invention.

Figure 5 is a schematic diagram showing a wafer inspection equipment equipped with a conventional centering guide.

6 is a perspective view illustrating a conventional centering guide.

7 is a cross-sectional view for explaining the operation of the conventional centering guide.

* Description of the symbols for the main parts of the drawings *

10: centering guide 12a, 12b: left and right guide block

14a, 14b: wafer seat end 16a, 16b: slip prevention jaw                 

18: pre-alignment table W: wafer

The present invention relates to a wafer inspection apparatus, and more particularly, to a centering guide for centering a wafer prior to alignment in a pre-align table of the wafer inspection apparatus.

In general, the wafer inspection process is one of the production processes of the semiconductor device, and the wafer inspection process is the last process. In the wafer inspection process, the inspection process such as determining the quality and defects by measuring the electrical and functional characteristics of the semiconductor elements formed on the wafer is performed. For this purpose, a cassette carrier is used by a robot arm. The wafer is removed from the cassette carrier, aligned in an exchange chamber and then inspected in a gun chamber.

Figure 5 is a schematic diagram showing a wafer inspection equipment equipped with a conventional centering guide, Figure 6 is a perspective view showing in detail a conventional centering guide.

As shown in FIG. 5, the wafer inspection equipment 60 is largely composed of a cassette carrier 61, a robot arm 65, an exchange chamber 72, and a gun chamber 80.

In order to inspect the wafer, the wafer stored in the cassette carrier 61 is first picked up by the robot arm 65 and moved into the exchange chamber 72, and the moved wafer is placed on the pre-alignment table 76.

Since the robot arm 65 places the house on the cassette carrier 61 as it is, the wafer is placed in such a manner that the center of the wafer is laid out.

If the center of the wafer is distorted as described above, data on defects or particles cannot be obtained accurately during the inspection process, and the reliability of such data is not only degraded, but also the inspection itself is impossible in severe cases. There is also.

Thus, as shown in FIG. 6, the centering guide 74 centers the wafer W on both sides of the pre-alignment table 76 to center the wafer W placed on the pre-alignment table 76. It is pushed toward and back to its place to make room for the wafer W to be pre-aligned.

The pre-alignment table 76 aligns the wafer while rotating 360 ° and then passes it from the exchange chamber 72 to the gun chamber 80 for wafer inspection. After the inspection, the wafer enters into the exchange chamber 72 and is aligned again. At this time, the wafer should be centered.

However, when the centering process of the wafer W is performed by using the centering guide 74 of the wafer inspection device 60 as described above, there is a problem in that a slip phenomenon occurs in the wafer.

This is due to the deflection of the edge portion of the wafer (W), the edge of the wafer is not properly caught in the centering guide 74, as shown in Figure 7 one end of the centering guide 74 It goes down and the other end is lifted up so that it covers the top of the centering guide 74.

As described above, when the slip occurs, the wafer is scratched on the surface, and in some cases, the wafer is broken.

In addition, since the failure occurred in the chamber, since the chamber itself needs to be opened and repaired, contamination may occur in the chamber, and damage to the inside of the chamber may be caused when the wafer is broken.

The present invention has been made to solve the above problems, the object of the present invention is to provide a slip prevention means, the wafer slip prevention means that can prevent the scratch or fracture due to the slip of the wafer during the centering process for pre-alignment It is to provide a centering guide having.

In order to achieve the above object, the present invention, in the wafer inspection equipment including a cassette carrier, a robot arm, an exchange chamber and a gun chamber, a pre-alignment table is provided in the exchange chamber,

Left and right guide blocks disposed opposite to the left and right sides of the pre-alignment table in the exchange chamber and moving in different directions, each of the opposing surfaces being concave and curved to match the edge shape of the wafer; And a wafer seating end attached to a lower end of each of the left and right guide blocks to protrude more toward the pre-alignment table than the concave opposing surface of each of the left and right guide blocks, and each of the left and right guide blocks. And a wafer slip prevention means attached to an opposite surface of the wafer seating end and configured to include a slip prevention jaw formed to be inclined downward toward the preliminary alignment table to hold the center of the wafer placed on the preliminary alignment table. Provide a centering guide.

Here, the wafer slip prevention means may be made of ceramics or stainless steel material.

In addition, the anti-slip jaw is preferably formed such that the angle of the downward inclined surface and the horizontal plane is in the range of 35 ° to 55 °.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view showing a centering guide according to an embodiment of the present invention, Figure 2 is a front view showing a right guide block of the centering guide according to an embodiment of the present invention, Figure 3 is an embodiment of the present invention It is a top view which shows the right guide block of the centering guide which concerns on an example.

As shown in FIG. 1, in the centering guide 10 according to the present invention, the left guide block 12a and the right guide block 12b are disposed opposite to left and right about the preliminary alignment table 18.

The left and right guide blocks 12a and 12b may be moved in opposite directions, ie, toward or away from the center, in order to grasp the center of the wafer W placed on the preliminary alignment table 18. Do.

In addition, the opposing surfaces of the left and right guide blocks 12a and 12b are in contact with an edge of the wafer W, and are concavely curved to conform to the edge shape of the wafer W. It is preferable.

The lower end of each of the left and right guide blocks 12a and 12b of the centering guide 10 formed as described above is provided with a wafer slip preventing means. The wafer slip preventing means includes a wafer seating end 14a and 14b and a slip prevention jaw ( 16a, 16b).

At this time, the wafer seating ends 14a, 14b are formed to protrude more toward the center side-toward the preliminary alignment table 18-than the concave opposing surfaces of the left and right guide blocks of the centering guide 10, respectively. The wafer W is slightly spread on the protruding portion. Therefore, the upper surface of the protruding portions of the wafer seating ends 14a and 14b may be formed at the same height as the upper surface of the preliminary alignment table 18 or lower than the upper surface of the preliminary alignment table 18.

The projecting degree d of the protrusions of the wafer seating ends 14a and 14b may vary depending on the size of the wafer, but is formed to fall within a range of about 0.04 to 0.2 mm so as not to damage the wafer W surface. It is desirable to. If the degree of protrusion (d) is less than 0.04 mm, there is a problem that the wafer (W) is not placed horizontally on the preliminary alignment table (18) due to the small area of the wafer (W) when the slip phenomenon occurs, 0.2, In case of exceeding mm, when the left and right guide blocks 12a and 12b of the centering guide move away from both sides again, the alignment of the aligned wafer W is changed due to the friction between the wafer W and the protrusion. have.

In addition, the thickness h of the wafer seating ends 14a and 14b may be formed to fall in a range of about 1 to 3 mm. When the wafer slip phenomenon occurs, the warp height of the wafer W is usually about 1 mm, so when the thickness h is less than 1 mm, there is a problem that such a slip phenomenon cannot be coped. There is a problem in that there is a lack of space inside to limit the movement of the centering guide (10).

The slip prevention jaws 16a and 16b are attached to opposite surfaces of the respective wafer seating ends 14a and 14b attached to the left and right guide blocks, and are inclined downward toward the center side-toward the preliminary alignment table 18. Is formed.

In particular, the anti-slip jaw is preferably formed such that the angle (θ) of the downward inclined surface is in the range of 35 ° to 55 °. When the angle θ is less than 35 °, the slip prevention jaws 16a and 16b should be relatively long while the wafer seating ends 14a and 14b are fixed. Since the space between 16b) is reduced, there is a problem in that the space for raising the wafer W can be reduced when the wafer slip phenomenon occurs, and when it exceeds 55 °, the wafer W becomes the wafer seating end 14a when the wafer slip phenomenon occurs. And 14b), it is difficult to move the left and right guide blocks at this time, thereby directly impacting the edge of the wafer W.

On the other hand, the wafer slip prevention means including the wafer seating end (14a, 14b) and the slip prevention jaw (16a, 16b) may be made of a ceramic material, or may be made of stainless steel material. .

In addition, the slip prevention jaw (16a, 16b) and the wafer seating end (14a, 14b) may be integrally made of the same material, it is also possible to be separately manufactured and merged with different materials.

Looking at the operation of the centering guide 10 according to the present invention.

Figure 4 is a cross-sectional view for explaining the operation of the centering guide according to an embodiment of the present invention.

When the wafer W picked up by the robot arm (not shown) is placed on the preliminary alignment table 18, the left and right guide blocks of the centering guide 10 which are spread on the left and right sides of the preliminary alignment table 18. (12a, 12b) moves gradually toward the center.

In this case, the wafer W having an unbalanced surface through various processes is easily liable to fall, and the slip prevention jaws 16a and 16b of the wafer slip prevention means support the edges of the wafer W. It is possible to prevent the wafer W, which is a problem, from entering under the guide blocks 12a and 12b.

The left and right guide blocks 12a and 12b of the centering guide 10 become narrower and return to their original positions when the edge of the wafer W comes into contact with the curved opposing surfaces of the guide blocks 12a and 12b. Move apart.

At this time, the wafer W is instantaneously slightly spread over the wafer seating ends 14a and 14b of the wafer slip preventing means, and helps to level the wafer.                     

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

As described above, according to the centering guide according to the present invention, by providing a wafer slip prevention means, it is possible to prevent scratches or fractures due to slip of the wafer during the centering process for preliminary alignment.

Claims (4)

A wafer inspection apparatus comprising a cassette carrier, a robot arm, an exchange chamber, and a gun chamber, wherein a pre-alignment table is provided in the exchange chamber, Left and right guide blocks disposed opposite to the left and right sides of the pre-alignment table in the exchange chamber and moving in different directions, each of the opposing surfaces being concave and curved to match the edge shape of the wafer; And A wafer seating end attached to a lower end of each of the left and right guide blocks to protrude more toward the pre-alignment table than a concave opposing surface of each of the left and right guide blocks, and each wafer seated to the left and right guide blocks. A wafer slip preventing means attached to an opposite surface of the stage and including a slip preventing jaw formed to be inclined downward toward the pre-alignment table; Centering guide, characterized in that it comprises a. The method of claim 1, The wafer slip preventing means is a centering guide, characterized in that made of a material of ceramics. The method of claim 1, And the wafer slip preventing means is made of stainless steel material. The method according to any one of claims 1 to 3, The slip preventing jaw is a centering guide, characterized in that formed so that the angle (θ) that the downward inclined surface and the horizontal plane is in the range of 35 ° to 55 °.

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