| 摘要 |
PURPOSE:To obtain a semiconductor device having excellent frequency characteristics, by forming an emitter region in a base region by a self-aligning method, and lowering the resistance of the base and the capacity between the base and a collector. CONSTITUTION:A silicon film, which has impurity diffusing source for forming an emitter region, is formed on a semiconductor substrate region, which is to become an emitter region 7. A base region 6 is formed by implanting ions partially through the silicon film. Then, by using the silicon film, the emitter region 7 is formed in the base region 6 by a self-aligning method. An insulating film is formed between the silicon film and a base-electrode taking-out region on the emitter region 7 by the self-alignment. The part between the base electrode and the emitter electrode is insulated. A base-electrode taking-out region is formed by the self-alignment. The interval between the emitter and the base is the thicknesses of an oxide film 107 on the side wall of a silicon film 603 and a nitride film 203. The base resistance becomes small. An emitter region 70 and the active base region 6 are simultaneously formed through the silicon film 603. Therefore, the region 70 and the region 6 are in approximately parallel. The width of the base is constant. The area of the base is reduced to a large extent. The capacity between the base and collector is decreased. |
