| 摘要 |
PURPOSE:To enable to apply uniformly a photo resist on the surface of a wafer by a method wherein the upper surface of a disk is made as the supporting face for the wafer, grooves are engraved nearly concentrically on the supporting face, and sucking holes are arranged in the bottoms of the grooves as to enable to obtain the sucking quantity proportional to the area of bottoms of the grooves. CONSTITUTION:To obtain the sucking quantity proportional to the area of bottoms of the grooves 8, it is favorable to open the holes well-balancedly in the bottoms by the number proportional to size of the diameters of the grooves 8 when the holes of the same size are to be engraved. The sucking holes 9 are connected to the central hole 11 of a supporting shaft 10 at the bottom of the disk 6 to facilitate sucking, and the disk 6 can be suckingly rotated. Because sucking force to the wafer at the upper face of the disk 6 to suckingly chuck the wafer becomes larger at the outside circumferential part, even when the wafer is rotated, coming up of the outside circumferential part thereof is not generated. |
