| 摘要 |
PURPOSE:To obtain the planar type semiconductor device with a high withstand voltage by a method wherein the first protection film of semiinsulation property having a dielectric constant of 7 or more is adhered to the surface of a semiconductor substrate with a P-N junction formed, and the second protection film of insulation property which interrupts the contaminations of Na ions and the like is laminated thereon to the same thickness, thereafter the substrate is annealed at 800-1,200 deg.C. CONSTITUTION:An N<-> type layer 3 serving as a collector region is epitaxially grown on the N<+> type semiconductor substrate 2 serving as a collector region, where a P type base region 4 is diffusion-formed, and an N type emitter region 5 is provided therein. Next, these regions are surrounded by a P<+> type guard ring region 6, which is further surrounded an N<+> type potential ring region 7. Thereafter, the first protection film 8 of semi-insulation property of polycrystalline Si, the dielectric constant of which is set at 7 or more by oxygen content is deposited while the thickness is set at 0.5mum or more, further the second protection film 9 of insulation property of the same thickness, such as PSG and Si3N4, which blocks the contamination of Na is laminated thereon, and the entire body is annealed at 800-1,200 deg.C. |
