| 摘要 |
PURPOSE:To realize an epitaxial layer through one-time process, and to mass- produce a transistor having high withstanding voltage VEBO between an emitter and a base simply by setting a base region at low impurity concentration. CONSTITUTION:An epitaxial layer 2 having one conduction type and low impurity concentration is laminated onto a semiconductor substrate 1 having the same conduction type and high impurity concentration. A collector region is formed by the layer 2. A base contact region 4 having a reverse conduction type and high impurity concentration is diffused into a prearranged region from the surface of the layer 2. The peripheral end of the surface of the epitaxial layer 2 is overlapped to the base contact region 4 from the surface of the layer 2, and the ions of an impurity giving one conduction type are implanted, thus shaping a base region 6 having predetermined withstanding voltage VEBO between an emitter and a base and impurity concentration of the low quantity of implantation. A prearranged emitter region 7 in the layer 2 is exposed, the impurity giving one conduction type is attached, the surface of the impurity is coated with a stabilizing film 8, and the emitter is diffused. Lastly, the stabilizing film 8 is left to insulating films 5, 9 on at least an emitter- base junction. |
