| 摘要 |
PURPOSE:To shorten the distance between an emitter region and a graft base region, and to reduce the emitter width by a method wherein the graft base region and a base resion are formed on a semiconductor substrate of th first conductivity type by a required process, and the emitter region of reverse conductivity type is formed in the base region. CONSTITUTION:After an N<+> type buried region 2 is formed on the P type semiconductor substrate 1, an N type semiconductor layer 3 is grown in liquid phase, and an insulation film of double-layer structure of a thin thermal oxide film 14 and a nitride film 13 is provided as a mask for selective oxidation. With the nitride film 13 left in a collector contact part 15 and the part where a base region 9 is provided, the nitride film 13 in the other part is etched away; thereafter, a field oxide film 4 is formed by selective oxidation. The oxide film 4 in the part where the graft base (GB) region 7 is to be formed is removed, and the GB region 7 is formed by ion implantation of a P type impurity, whereas the base region 9 is formed by P type impurity implantation. The emitter region 10 and the collector contact 5 are formed by diffusing an N type impurity, and collector, base, and emitter electrodes 6, 8, and 11 are provided. |
