| 摘要 |
PURPOSE:To obtain a thyristor having no damage in case of separating a thyristor pellet and good characteristics by providing a partition region slightly separating a thyristor pellet and good characteristics by providing a partition region slightly separated from a thyristor region by etching, forming grooves from the back surface on the region, forming cracks which arrive at the groove from the front surface and separating individual pellet thyristor regions. CONSTITUTION:A portion between a partition region 8 disposed adjacent to a thyristor region 2 and the region 2 is etched to the midway depth from the surface of a wafer 1. Thus, the bonded portions of an N<+> type layer 7 to become a cathode and gates 5 are formed in a bevel shape to improve the withstand voltage of a thyristor. A groove 9 is formed from the back surface of the wafer 1 to the midway depth in the region 8. This groove is etched after a cutout is formed by dicing or sandblasting to remove the damage around the groove 9. Thus, the junction of the layer 3 is exposed without strain in the region 2. The region 2 is separated in pellet shape by forming a crack 10 to the groove 9 from the surface of the wafer 1. |
