| 摘要 |
PURPOSE:To relax an electric field in the curvature section of a junction sufficiently, and to increase withstanding voltage by providing a first impurity region, an annealing region, a field plate resistance layer and a high concentration impurity region having the same conduction type as a specific semiconductor substrate. CONSTITUTION:A base region and an N<+> layer 4 through annealing surrounding the base region at a regular interval are formed in a predetermined region on the main surface side of a semiconductor substrate 1, and a field plate resistance layer 6 is shaped onto a dielectric layer 5 between the base region and the N<+> layer 4. An N conduction type high concentration impurity region 10 is formed in a projecting manner so as to be oppositely faced to the base region in a region on the back side of the semiconductor substrate 1 oppositely faced to the base region. The side surface section of the high-concentration impurity region 10 is set so as to be positioned between an emitter region and the N<+> layer 4, and the projecting width T of the high concentra tion impurity region 10 is set so as to satisfy t2<T<=t2+2W0 where t2 represents the junction width of a second impurity region 3, T the projecting width of the high concentration impurity region 10 and W0 a space between a first impurity region 2 and the high concentration impurity region 10. |
