JPS6238854B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wafer pushing device, and more particularly to a wafer pushing device suitable for pushing up a positioned wafer.

A wafer lifting device conventionally provided in a preliminary chamber of a processing chamber of a semiconductor manufacturing device such as an etching device will be explained with reference to FIG.

In FIG. 1, there is a holder 11 at the bottom of the preliminary chamber 10.
is set up airtight. A press plate 13 is provided on the top of the holder 11 with a flange 12 interposed therebetween. At the bottom of the holder 11, a bracket 15, on which a bracket 14 is provided, is provided vertically. The bracket 14 is provided with a drive device, such as an air cylinder 16, which operates unstably at the beginning of the drive. A lower end of a coupling ring 18 is screwed into one end of the piston 17 of the air cylinder 16. At the top of the coupling ring 18, there is a push button 1.
A lower end of a shaft 20 is provided which is supported in elevation by a presser plate 13 via a shaft 9 . A table 22 on which a wafer 21 is placed is provided at the upper end of the shaft 20. An O-ring 23 for preventing slipping is provided on the outer periphery of the surface of the table 22. Flange 12
A bellows 24 for airtightness is provided between the shaft 20 and the shaft 20, surrounding a part of the shaft 20.

The wafer 21 that has been transported and positioned by another transport means (not shown) is placed on the table 22 and pushed up by driving the air cylinder 16 and raising the table 22 via the shaft 20. Thereafter, the pushed-up wafer 21 is further received by another transport means (not shown) and transported from the preliminary chamber 10 to the processing chamber (not shown). Furthermore, the table 22 from which the wafer 21 has been removed by another conveying means is
It is lowered by the air cylinder 16 via the shaft 20 and returned to its original position.

In such a wafer lifting device, the air cylinder operates unstablely at the initial stage of operation, making it impossible to raise the table smoothly. There was a drawback that this occurred.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a wafer pushing device that eliminates the drawbacks of the prior art described above and can prevent a wafer from shifting when a positioned wafer is placed on a table and pushed up.

The present invention provides a wafer lifting device with a shaft means capable of being raised and lowered, which comprises a shaft provided with a table on which a wafer is placed, and a guide body provided on the shaft with a guide hole formed in the vertical direction from the bottom. , a drive means for lowering the shaft means with elastic force; a push-up means having a push-up surface on an upper end face and provided in the guide hole so as to be movable up and down; and a drive means for raising and lowering the push-up means. an elevating drive means for raising the shaft means via the push-up means against the elastic force of the elevating means; a pushing surface of the directional push-up means that stops the lowering by the elevating drive means; and a stopper means for stopping the lowering of the shaft means by maintaining an actuation dead zone space between the pushing-up surface and the opposing surface of the guide hole of the guide body, so that the lifting drive means can be Even if the wafer operates unstablely at the initial stage of driving, the wafer will not be misaligned when it is placed on the table or when it is pushed up.

An embodiment of the present invention will be explained with reference to FIG.

FIG. 2 is a longitudinal cross-sectional view of a wafer lifting device according to the present invention applied to a preliminary chamber provided in a processing chamber of a semiconductor manufacturing device such as an etching device. Devices and the like that are the same as those in the figures are designated by the same reference numerals and their explanations will be omitted.

In FIG. 2, the shaft means is composed of a shaft 20 and a guide body 27. The elevating drive means is, for example, an air cylinder 16. The push-up means is composed of a collar 28 and a guide rod 29. The driving means for lowering the shaft means is, for example, a spring 32. The stopper means is a stopper 31. Guide body 27
A guide hole 26 having a protrusion 25 on the inner wall is formed in the guide hole 26 . The collar 28 has a shape and size that allows it to engage with the protrusion 25 and not come into contact with the inner wall of the guide hole 26, and is provided at the upper end of the guide rod 29 with its center aligned with the axis of the guide rod 29. ing. In this state, the guide rod 2 allows the collar 28 to move up and down within the guide hole 26.
9 is inserted into the guide hole 26. Therefore, in this case, the upper surface of the collar 28 becomes the upper end surface of the push-up means. A guide body 27 is provided at the lower end of the shaft 20 with a set bolt 30. In this case, the axial center of the shaft 20 and the axial center of the guide hole 26 coincide, and the lower end surface of the shaft 20 faces the upper surface of the collar 28 and is exposed within the guide hole 26. Therefore, in this case, the lower end surface of the shaft 20 becomes the lower end surface facing the upper end surface of the pushing-up means of the shaft means. The lowering of the guide body 27 is stopped by a stopper 31 provided on the bracket 15. A spring 32 is provided between the holder 11 and the guide body 27 to lower the raised guide body 27 and bring its lower end surface into contact with the stopper 31. The lower part of the guide rod 29 is screwed into the upper part of the coupling ring 18. In this case, the upper surface of the collar 28 that has stopped descending in the air cylinder 16 and the spring 3
The shaft 20 whose descent at step 2 is stopped by the stopper 31
An operating dead zone space is maintained within the guide hole 26 between the lower end surface of the guide hole 26 and the lower end surface of the guide hole 26 . The depth of this operation dead zone space is determined by the tsuba 2 until the air cylinder 16 operates stably.
The depth is such that the upper surface of the shaft 8 does not come into contact with the lower end surface of the shaft 20.

When a wafer (not shown) that has been transported and positioned by another transport means (not shown) is placed on a table (not shown) and pushed up, the air cylinder 16 is first driven. After a certain period of time elapses after the air cylinder 16 is driven, the piston 17 starts to rise rapidly, and the guide rod 29 moves toward the coupling 18.
It rises rapidly in the guide hole 26 through the guide hole 26. after that,
When the piston 17 has stabilized in its upward movement, the collar 28 comes into contact with the lower end of the shaft 20, and the shaft 20 moves upward together with the guide body 27 against the spring force of the spring 32.
As a result, the positioned wafer is placed on a smoothly rising table and pushed up. Further, after the pushed-up wafer is received by another conveyance means (not shown), the guide rod 29 is lowered through the coupling ring 18 into the air cylinder 16 and the guide hole 26, and the spring force of the spring 32 is lowered. By pressing down the guide body 27 and bringing it into contact with the stopper 31, the table is returned to its original position via the shaft 20.

In the wafer lifting device of this embodiment, the sudden rise of the air cylinder at the initial stage of driving is transmitted to the shaft by the action of the actuation dead zone space maintained between the lower end surface of the shaft and the upper surface of the flange. Since the table can be raised smoothly without any problems, the positioned wafer can be placed on the table and pushed up smoothly, and the position of the wafer can be prevented from shifting when being placed or pushed up. can.

According to the present invention, it is possible to smoothly place a positioned wafer on a table and push it up, so that it is possible to prevent the wafer from shifting when it is placed on the table and pushed up.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of a conventional wafer lifting device, and FIG. 2 is a partial vertical sectional view showing an embodiment of the wafer lifting device according to the present invention. 16...Air cylinder, 17...Piston,
20...shaft, 22...table, 25...protrusion,
26... Guide hole, 27... Guide body, 28... Tsuba,
29... Guide rod.

Claims (1)

[Claims] 1 A vertically movable shaft means consisting of a shaft provided with a table on which a wafer is placed and a guide body provided on the shaft with a guide hole formed in the vertical direction from the bottom, and the shaft means lowered by elastic force. a driving means for causing
a push-up means that has a push-up surface on its upper end face and is provided in the guide hole so as to be able to rise and fall; A lifting drive means for raising the shaft means, a pushing-up surface of the pushing-up means that has stopped descending by the lifting-driving means, and a pushing-up surface of the guide hole of the guide body that is lowered by the driving means, facing the pushing-up surface. A wafer lifting device comprising: a stopper means for stopping the descent of the shaft means by maintaining an actuation dead zone space between the shaft means and the surface.