| 摘要 |
PURPOSE:To prevent generation of stress by a method wherein the first semiconductor layer is grown on a semiconductor substrate, a plurality of plane surfaces having different heights are formed oxidating and etching a part of said semiconductor layer, the second semiconductor layer is grown, and a part of the semiconductor surface is electrically isolated by oxidation. CONSTITUTION:An N<+> type buried layer and a P<+> channel stopper 103 are diffused on a P type semiconductor substrae 101, and an N type epitaxial layer 104 having the thickness approximately ond half of the epitaxial layer is grown. Then, a thin oxide film 105 and a nitride film 106 are grown, and a window is provided. Subsequently, a thick oxide film 107 is formed. Then, said thick oxide film, the thin oxide film 105 and the nitride film 106 are removed, and an epitaxial layer 104' is grown again until it will be formed to the desired thickness. A thin oxide film 105' and a nitride film 106' are grown again, and a thick oxide film 107' is formed. Besides an N<+> type diffusion layer 108 is formed, a P type base region 110 is diffused, and after an N<+> type emitter region 112 has been diffused, a metal wiring 113 is vapor-deposited. As a result, the stress accumulated on the region located in the vicinity of the interface of the oxide film and the semiconductor is reduced, thereby enabling to improve the withstand voltage of the semiconductor device. |
