| 摘要 |
PURPOSE:To reduce the irregularity of trigger current in a planar thyristor due to its boundary level by forming a diffused layer extended from the surface in a diffused region between a cathode region and a gate region in the thyristor. CONSTITUTION:A p-type layer 4 is diffused on the back surface of an n-type semiconductor substrate 1, and the periphery of the substrate 1 is surrounded by a p-type region 3 and isolated from the other region. A p-type region 5 is diffused on the surface layer of the substrate 1, an n-type cathode region 6 is formed in the region 5, and an aluminum electrode 7 is coated on the region 6. When a gate electrode 8 is mounted partially on the region 5 and an oxide film 2 is coated on the exposed surface as a thyristor structure, an n-type region 9 surrounding the region 6 is formed in the region 5. Since the irregularity of gate trigger current in the thyristor is reduced due to the boundary level in the configuration thus formed, the thyristor can be fabricated with preferable reproducibility. |
