| 摘要 |
PURPOSE:To prevent the lowering of reverse dielectric resistance between a base and a collector by a method wherein a latticed groove is formed to one surface of a substrate, an impurity having a reverse conduction type to the substrate is introduced from both surfaces and the surface of a remaining buried region is exposed and used as a base region. CONSTITUTION:The latticed grooves 21 are formed to the surface of the P type semiconductor substrate 20, the N ttype impurity is diffused from both surfaces in the atmosphere of phosphorus oxychloride, and the P type buried regions 22 are shaped so that the diffusion of the impurity from both surfaces of the substrate is connected just under the grooves 21. An N<+> type region 23 is removed from the surface side of the substrate so that the surfaces of the buried regions 22 are exposed, and an emitter region 24 is shaped by diffusing the N type impurity into the buried regions 22. Since the buried regions 22 functioning as the base regions and the N<+> type region 23 serving as a collector region are formed simultaneously, the generation of pipy diffusion can be prevented, and defective dielectric resistance between the base and the collector can be removed. |
