| 摘要 |
PURPOSE:To obtain a composite semiconductor device of high reliability having no deterioration of the hFE and no deterioration of the withstand voltage by a method wherein groove parts formed as to surround individual semiconductor elements by removing a silicon oxide film are provided in the silicon oxide film formed on a semiconductor substrate, poly-silicon layers are provided at the parts to cover the groove parts, and moreover a silicon oxide film is provided on the surface thereof, and an electrode metal wiring for mutual wiring is arranged. CONSTITUTION:The groove parts 11, 12 of a silicon oxide film 7 are formed as to surround transistors Tr1, Tr2, a silicon nitride film 13 is formed on the surface containing the groove parts 11, 12, and because ions can transfer only from limited parts, the absolute quantity thereof is reduced, and inversion is hardly generated. Poly-silicon films 14, 15 are formed on the film 13, and a polysilicon guard ring 16 is formed on a channel stopper. The surfaces of the poly-silicon films thereof are covered by a silicon oxide film 17 to act as an insulating layer, openings 18, 19 to communicate with the emitter region of the transistor Tr1 and with the base region of the transistor Tr2 are formed, and because an Al wiring 8 is laid after completion of insulation, even when an electric field is applied, it is absorbed by the poly-silicon film, mobile ions are hard to be collected, and accordingly an inversion is also hard to be generated. |
