| 摘要 |
PURPOSE:To mitigate the electric field intensity in a depletion layer of a thyristor by providing an insulating isolation island in a semiconductor substrate and forming a gate region of the thyristor in the semiconductor region making contact with an insulating film surrounding the island when forming the gate region. CONSTITUTION:A groove 2 is formed in a polycrystalline silicon substrate 5, an isolation dielectric film 4 is coated on the side walls and bottom of the groove 2, and a monocrystalline silicon p-type base region 3 is formed from the side walls to the bottom surface of the groove 2. At this time a region 7b internally projected in the surface layer is extended at one side wall of the region 3, and an n-type cathode region 8 is diffused in the region 7b. Then, the residual space in the region 3 of the groove 2 is filled with an n-type base region 1, and a p-type anode region 7a is formed on the center of the surface layer partially on the region 1. The thyristor is thus formed, an insulating film 6 is coated on the surface, openings are formed at the film 6, and anode wire 9a, a gate wire 9b and a cathode wire 9c are extended through the openings from the regions 7a, 3 and 8, respectively on the film 6. |
