| 摘要 |
PURPOSE:To eliminate a quality problem caused by the produced step difference by a method wherein a high density diffusion is performed to the part where a polycrystalline silicon and a semiconductor substrate get direct contact with each other and then the polycrystalline silicon is etched. CONSTITUTION:A high density diffusion is not performed to a polycrystalline silicon 406 in a domain of a through-hole 403 of the part where the polycrystalline silicon and a semiconductor substrate 401 get direct contact with each other and the diffusion is performed to the through-hole domain after the polycrystalline silicon is etched. As a result, because the substrate 401 is etched only to the extent of an excess etching which is necessary to etch completely the polycrystalline silicon which has low etching rate and is not diffused, the step difference is not produced in the direct contact domain when the polycrystalline silicon is etched. Therefore, a layer insulation and coverage of a wiring in the direct contact domain are improved. |
