| 摘要 |
PURPOSE:To obtain high gate sensitivity, large critical ON current increasing ratio and large critical OFF current increasing ratio without increasing gate current by adding a diffusion layer to a base layer. CONSTITUTION:A P type base layer 2 and a P type emitter layer 3 are formed on both sides of an N type substrate 1 and on the surface of the P type base layer 2, an N type emitter layer 4 is formed in such a manner that the P type base layer protrudes locally to the upper side of the emitter layer 4 through short circuit holes 8. Then an independent N<+> type impurity diffusion layer 9 which has ring-form and has no connection to other parts is formed between a control (gate) electrode 5 formed on the surface at the center of the base layer 2 and a ring-form emitter electrode 6 which makes short-circuit between the base layer, which is exposed on the surface through many short-circuit holes 8 which are formed on the surface of the N type emitter layer 4 and pierce the emitter layer locally, and the emitter layer 4. |
