| 摘要 |
PURPOSE:To prevent the occurrence of cracks and chipping at a cut face so as to improve yield rate by polishing and thinning a substrate, and separating a wafer with a scriber, making use of the stress by the warp occurring in the wafer. CONSTITUTION:A gallium nitride compound semiconductor 2 is stacked on a sapphire substrate 1. Next, the sapphire substrate 1 is polished and thinned, and then it is warped in the shape of a convex. Next, the wafer is put into nearly the shape of a plate shape, and it is scribed to form scribe lines it. Since the upward stress of the wafer works at all times, it can be separated, being cutting from the scribe line in the midst of making the scribe line or when having released it from a vacuum chuck. Hereby, a compared with the method of cutting it by dicing, a number of small chips can be formed and the productivity can be improved. |
