| 摘要 |
PURPOSE:To easily expand the depletion layer and to obtain a high withstand voltage for the planar type transistor used on subject semiconductor device by a method wherein the annular groove, protected by an insulating layer from the surface of a substrate, is provided in the collector region located around the connected section of a base collector. CONSTITUTION:The NPN (PNP) transistor of a planar type is formed by providing a P(N) type base layer 2 and an N(P) type emitter layer 3 on an N(or P) type substrate 1. Within the expanding range of the depletion layer 8 located outside the connected surface of the base collector, the annular groove 4 surrounding the junction part is provided and a construction is formed in such manner that the insulating layer 5 is protected by having it buried in the groove 4. Through these procedures, the depletion layer 8 of the collector can be spread out over the groove section 4, and said spreading section of the layer 8 is not terminated on the surface adjacent to the connected surface, the breakdown voltage close to the bulk can be obtained and the transistor of high withstand voltage can be obtained. |
