JPH03228348A - Vacuum chuck for semiconductor wafer - Google Patents

Abstract

PURPOSE:To avoid deformation of a semiconductor wafer while removing the effect of dust when chucking by establishing a plurality of circular dust grooves which have the same width as that of a suction groove concentrically between adjacent circular suction grooves on a suction face. CONSTITUTION:A vacuum semiconductor wafer chuck has a surface 2 where concentric circular suction grooves 3 are provided with suction holes 5 in their bottoms. A plurality of concentric circular dust grooves 7 which have the same width of that of the suction groove 3 are provided at the surface 2 between the adjacent suction grooves 3. Take the following for example. Tow concentric circular suction grooves 3 are provided, respectively, in central and peripheral portions of the surface 2 of a disklike metal or ceramic chuck body 1. The individual suction grooves 3 have suction holes 5 at regular intervals in their bottoms, and all the holes communicate in a chamber 4 established inside the chuck body 1. Between the suction grooves 3, concentric circular dust grooves 7 which have the same width and depth as those of the suction groove 3 are made at an appropriate interval.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a vacuum chuck for semiconductor wafers that vacuum-chucks semiconductor wafers for flatness measurement, lapping, or grinding of semiconductor wafers such as silicon wafers. .

[Prior Art] Conventionally, this type of vacuum chuck for semiconductor wafers has a vacuum chuck as shown in FIG. , a plurality of suction grooves 12 with suction holes 11 at the bottom.
are provided concentrically on the suction surface 14 of the chuck body 13, and concentric recesses 15 are provided on the suction surface 14, leaving the periphery of these suction grooves 12 (see Utility Model No. 60-192).
445), or as shown in FIG. 5, in the above structure, a leak hole 16 communicating with the bottom of the recess 15 is provided (see Utility Model Publication No. 62-23).
(See Publication No. 447).

[Problems to be Solved by the Invention] However, although each of the conventional vacuum chucks for semiconductor wafers described above is provided with the recessed portion 15, the influence of dust can be eliminated; however, in the case of the one shown in FIG. Since the inside of the recess 15 is also vacuum-suctioned through the suction groove 12, there is a problem that the semiconductor wafer W is curved and deformed so as to protrude into the recess 15, as shown in FIG. In the case shown, the inside of the recess 15 communicates with the atmosphere and the pressure becomes higher than that inside the suction groove 12, so the corresponding part of the recess 15 of the semiconductor wafer W protrudes outward as shown in the figure. There is a problem with it bending and deforming.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a vacuum chuck for semiconductor wafers that can chuck semiconductor wafers while eliminating the influence of dust and preventing deformation of semiconductor wafers.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the vacuum chuck for semiconductor wafers of the present invention has a vacuum chuck for semiconductor wafers which has a suction surface provided with a plurality of suction grooves concentrically provided with suction holes at the bottom. In the vacuum chuck, a plurality of dust grooves having the same groove width as the suction grooves are concentrically provided on the suction surface between the adjacent suction grooves.

[Operation] In the above means, the dust interposed between the suction surface and the semiconductor wafer is captured in the dust groove as it moves toward the suction groove during vacuum suction, and the semiconductor wafer is also It is supported by a suction surface between the grooves or between the dust groove and the suction groove.

When the width of the dust groove is smaller than the width of the suction groove, the dust trapping efficiency decreases, and when it becomes larger than the width of the suction groove, the semiconductor wafer is deformed.

[Example code] An embodiment of the present invention will be described below with reference to the drawings.

1 and 2 are a plan view and a sectional view of a vacuum chuck for semiconductor wafers according to the present invention.

In the figure, reference numeral 1 denotes a disc-shaped chuck body made of metal, ceramics, etc., and its suction surface 2 has two concentric suction grooves 3 located at the center and outer circumference. At the bottom of each suction groove 3, a plurality of suction holes 5 are opened at equal intervals in the circumferential direction and communicated with each other via a communication chamber 4 provided inside the chuck body 1. 4 is
It is provided so as to be connectable to a vacuum pump (not shown) via a vacuum suction port 6 provided on the back surface of the chuck body 1.

Between the surface suction grooves 3, a plurality (two in the figure) of dust grooves 7 having the same groove width and depth as the suction grooves 3 are provided concentrically with appropriate intervals.

In the vacuum chuck for semiconductor wafers having the above configuration, when vacuum suctioning the semiconductor wafer W, the vacuum pump is operated to vacuum suction the inside of the suction groove 3 through the vacuum suction port 6, the communication chamber 4, and the suction port 5, and the suction surface 2 and the semiconductor wafer W, as detailed in FIG. The W is supported by a suction surface existing between adjacent grooves 81 or between the dust groove 7 and the suction groove 3.

Therefore, it is possible to chuck the semiconductor wafer W without interposing the dust D between the suction surface 2 and the semiconductor wafer W and without deforming the semiconductor wafer W.

In addition, in the above embodiment, the case where there are two suction grooves 3 has been described, but the invention is not limited to this.
For example, if the semiconductor wafer W has a large diameter, the number of suction grooves 3 is three or more, and the suction surface 2 between adjacent suction grooves 3 is used for this suction. *Two or three or more dust grooves 7 having the same groove width as in 3 may be provided concentrically.

In addition, the suction groove 3 and the dust groove 7 are limited to circular shapes.
It is also possible to arrange arcs in a circular shape.

[Effects of the Invention] As described above, according to the present invention, the dust interposed between the suction surface and the semiconductor wafer is captured in the dust groove as it moves toward the suction groove during vacuum suction, and Since the semiconductor wafer is supported by a suction surface between adjacent dust grooves or between a dust groove and a suction groove, deformation of the semiconductor wafer can be prevented without intervening dust between the suction surface and the semiconductor wafer. It can prevent chucking.

[Brief explanation of drawings]

1 and 2 are a plan view and a sectional view of a vacuum chuck for semiconductor wafers showing one embodiment of the present invention, FIG. 3 is a sectional view showing its operation, and FIGS. 4 and 5 are respectively conventional FIG. 3 is a cross-sectional view showing the operation of the semiconductor wafer vacuum chuck of FIG. 1 Chatter body 2 Suction surface 3 Suction groove 5 Suction hole 7 Dust groove W Semiconductor wafer D Dust

Claims (1)

[Claims] 1) In a semiconductor wafer vacuum chuck in which a plurality of suction grooves with suction holes at the bottom are concentrically provided on the suction surface, a plurality of grooves having the same width as the suction grooves are provided on the suction surface between the adjacent suction grooves. A vacuum chuck for semiconductor wafers characterized by concentric dust grooves.