| 摘要 |
PURPOSE:To improve the withstand voltage of an element as well as to stabilize the surface of the device by a method wherein the silicon oxide film, which will be used as the source of impurity diffusion, is left over on a substrate excluding a capacitor region. CONSTITUTION:After a P type base region 2 has been formed on the surface of an N type semiconductor substrate 1, window sections 4 and 5 are provided on an insulating layer 3. Then, a silicon oxide film (PSG film) 6, whereon phosphorus was doped, is coated on the above. The N<+> layers 7 and 8, containing high concentration of phosphorus, which were formed in the above-mentioned process, are stretched and diffused, and an N type emitter region 7a and an N type semiconductor region 8a are formed. Oxide films 9 and 10 are grown on the window sections 4 and 5 in the above process. Subsequently, after the PSG film and the oxide film on the window section 5 have been removed, a thermal oxide film 11 is formed. An emitter electrode 12 and the like are formed, and at the same time, an electrode 13, consisting of a capacitor whereon the thermal oxide film 11 is used as a dielectric, is formed. |
