JPH0129787Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a centering device for determining and setting the center position of wafers, masks, etc. for semiconductor manufacturing.

[Conventional technology]

In the semiconductor manufacturing process, correctly setting the center position of the wafer, etc. on the processing equipment prevents damage and ensures stable processing, as well as the correct setting of the wafer orientation flat, which is an important factor that greatly affects product yield. It's work. Currently, this work is done manually, or by a simple automatic method, in which the wafer, etc., transported by a transport belt is stopped at a centering piece set at a specified position, and the center of the wafer, etc. is held by a chuck installed at the bottom of the centering piece. This is done by a device. However, with this kind of equipment, if there are variations in the external dimensions of the wafer etc., sufficient precision cannot be obtained, making it difficult to perform stable processing and making it impossible to obtain products with a high yield. development was desired.

[Problem that the invention attempts to solve]

The above-mentioned simple automatic device cannot be used correctly due to variations in the outer diameter of the wafer, misalignment in the left and right directions of movement that occur during transportation, and dimensional errors when the orientation flat part of the wafer hits the centering piece first. It was difficult for the chuck to hold the object to be centered at the center position.

This idea is designed to prevent unevenness in the outer diameter of the object to be centered, such as a wafer, or lateral positional deviation during transportation.
Another object of the present invention is to provide a centering device that can properly fit and hold the center of a wafer in a chuck regardless of the presence or absence of an orientation flat portion.

[Means and actions for solving problems]

This design has an inner surface similar to the shape of the object to be centered when viewed from the top, the upper dimension is larger than the outer dimension of the object to be centered, the lower dimension is narrower, and the tapered shape opens toward the top. A centering cup in the form of a bottomless cup having an inner slope of
Insert the object to be centered into the centering cup and place it on this horizontal chuck, and then move the centering cup up and down to make the object to be centered slide along the inner slope of the cup, and place it on the horizontal chuck so that its posture is horizontal. By correcting this, the center of the object to be centered is found and the object to be centered is held in the correct position by a horizontal chuck.

This invention performs accurate centering processing by vertically centering the centering cup.

〔Example〕

An embodiment of this invention will be described below with reference to the drawings.

FIG. 1 is a plan view of this embodiment, and FIG. 2 is a longitudinal side view thereof. FIGS. 3 and 4 are explanatory diagrams of the operation of this embodiment.

1 has an inner surface similar to the shape of the object to be centered when viewed from the top; for example, if the object to be centered is a wafer, it is circular; the dimension of the top is larger than the outer diameter of the wafer, and the dimension of the bottom is similar to the shape of the object to be centered; This is a bottomless centering cup having a narrow, tapered inner slope that opens upward, and a horizontal chuck 2 for placing and holding an object to be centered at the center position inside this cup 1.
is provided, and at one end of the centering cup,
A centering piece 3 is provided to define the stopping position of the wafer, etc. being transported, and a belt 4 is provided from the other end to the inside of the cup 3 for transporting the wafer, etc. 5 is a first cylinder that moves the centering piece 3 and the conveyor belt 4 up and down. A second cylinder 6 serves as a vertical drive mechanism for vertically moving the centering cup 1 to perform a centering operation. 7
After the centering operation is completed, the third stage raises the horizontal chuck 2 and prepares to send the wafer etc. to the next process.
The cylinder 8 is an object to be centered, such as a wafer. 11 indicates the inner slope of the centering cup.

Next, the operation of this embodiment will be explained with reference to FIGS. 3 and 4.

An object to be centered, for example, a wafer 8, is fed from the left side by the conveyor belt 4, and when it stops at the position of the centering piece 3, the centering piece 3 and the conveyor belt 4 are lowered by the operation of the first cylinder 5. The wafer 8 placed on the conveyor belt 4 is also lowered, inserted into the centering cup 1 and placed on the horizontal chuck 2.
When the wafer 8 is placed on the horizontal chuck 2, the centering cup 1 is raised by the action of the second cylinder 6.

At this time, the center of wafer 8 is at centering cup 1.
If the wafer 8 is placed on the horizontal chuck 2 at a position offset from the center of the wafer 8, the outer circumference of the wafer 8 in the offset direction will contact the tapered inner slope 11 of the centering cup 1, slide on this slope 11, and move to the center. The position is corrected in the direction. When the lifting movement of the centering cup 1 is completed, the centering cup 1 moves to the second cylinder 6.
The wafer 8 is lowered by the operation of , and the wafer 8 is placed on the horizontal chuck 2 . The centering cup 1 is again raised by the action of the second cylinder 6 and performs the same centering action as described above. Although this operation can improve the accuracy to a certain extent even once, it is usually done multiple times to ensure that the object to be centered slides on the inner slope 11 of the centering cup 1, thereby changing its horizontal position and resting on the horizontal chuck 2. By doing so, its posture is corrected horizontally and more accurate centering is possible.

Further, during the centering operation, the horizontal chuck 2 is rotated forward and backward in the horizontal direction so that the outer peripheral surface of the wafer 8 conforms to the slope 11, thereby making it possible to perform the centering process more accurately and quickly.

When the centering operation is completed, horizontal chuck 2
The wafer 8 is vacuum-suctioned to fix its position, the horizontal chuck 2 is raised by the third cylinder 7, and the wafer 8 is sent to the next process by a wafer unloading mechanism (not shown). The horizontal chuck 2 returns to its original position by the operation of the third cylinder 7, and at the same time the centering piece 3 and the conveyor belt 4 also move to the first cylinder 5.
The operation returns to the original position and one process is completed.

As explained above, the main feature of this invention is that the centering operation of moving the centering cup 1 up and down, which has a tapered inner slope 11 similar to the object to be centered, enables accurate centering without touching the surface of the wafer 8. be.

FIG. 5 shows another embodiment of this invention.

This embodiment is used, for example, when locating a mask and placing it on the wafer in order to perform masking on the wafer.

Normally, the mask has a rectangular shape, but by providing a rectangular centering cup 1 similar to the shape of the mask as shown in FIG. 5, it becomes possible to accurately locate the mask.

It should be noted that this invention is not limited to the above-mentioned embodiments, but can be implemented with various modifications without changing the gist. For example, the shape of the inner slope of the centering cup 1 may be a special shape instead of a circle or a rectangle.

Furthermore, if the position of the orientation flat part of the wafer can be defined to some extent when transporting the wafer, the shape of the inner slope 11 of the centering cup can be made similar to the shape of the wafer including the orientation flat part. Centering processing that can also define the position of the station flat portion becomes possible.

Furthermore, this invention can be used not only as a centering device scale for semiconductor manufacturing, but also for centering objects in other industrial fields.

[Effect of idea]

A major feature of this device is the centering operation in which the centering cup, which has a tapered inner slope similar to the object to be centered, is moved up and down. Even if there is a defect such as a flat or a positional shift during transportation, the center of the object to be centered can be determined with high accuracy.

It can also be used for centering objects whose external shape is a special shape other than circular or rectangular.

This invention enables accurate centering, which allows the subsequent processing of wafers to be carried out stably and accurately, making it possible to obtain products with a high yield. In particular, when the wafer is rotated at high speed, such as during processing using a spin rotation section, accurate center grasping according to this invention becomes even more effective.

Furthermore, when detecting the orientation flat portion of a wafer, particularly high center position accuracy is required, and this invention is also very effective in this respect.

Also, according to the centering device according to this invention,
Since the centering operation is performed using the outer periphery of the part to be centered as a reference, processing can be performed without touching the surface of the object to be centered.
It becomes possible to manufacture high-quality products without damaging important surfaces such as masks.

[Brief explanation of the drawing]

Fig. 1 is a plan view of one embodiment of this invention, Fig. 2 is a longitudinal cross-sectional side view of the same embodiment, Figs. FIG. DESCRIPTION OF SYMBOLS 1... Centering cup, 2... Horizontal chuck, 3... Centering piece, 4... Conveyor belt, 5... First cylinder, 6... Second cylinder, 7... Third cylinder, 8... ...wafer, 11
...inner slope.

Claims (1)

[Claims for Utility Model Registration] (1) The shape seen from the top is similar to the shape of the object to be centered, and the dimensions of the upper part are larger than the external dimensions of the object to be centered, and the dimensions of the lower part become narrower toward the top. a bottomless centering cup with an open tapered inner slope;
A horizontal chuck is provided at the center of the centering cup and has a horizontal holding surface on which the object to be centered is placed, a transport mechanism for loading and unloading the object to be centered into the centering cup, and a transport mechanism for carrying the object to be centered into and out of the centering cup; 1. A centering device for wafers, etc., comprising a centering piece that stops a sent object to be centered at a predetermined position, and a vertical drive mechanism that moves the centering cup up and down. (2) The centering device for wafers, etc., as set forth in claim 1, wherein the centering cup has a circular inner surface when viewed from above. (3) The centering device for wafers and the like as set forth in claim 1, wherein the centering cup has an inner surface having a rectangular shape when viewed from above. (4) Utility model registration claims 1 to 3, characterized in that the horizontal chuck is rotated forward and backward in the horizontal direction during centering operation.
A centering device for wafers, etc., as described in any of the above.