| 摘要 |
PURPOSE:To effectively prevent parasitic effect and to prevent the infiltration of contaminants and impurity atoms to the substrate surface by a method wherein the field oxide film of the substrate is provided on conductive layers made of poly Si formed at the same time with a gate electrode. CONSTITUTION:Buried type field oxide films 30 are formed at the field region 27 by selective oxidation, and the conductive layers 31 are formed thereon by depositing poly Si at the same time with the gate electrode 26; furthr, a CVD oxide film 32 is formed so as to cover this conductive layer 31. The poly Si is doped with the phosphorus giving N type toreduce the resistivity, and the poly Si is thereafter etched into the gate electrode 26 and the conductive layer 31. Since the conductive layers 31 are formed over the field region 29, these layes 31 are always present under the wiring provided on the CVD oxide film 32. Thereby, the electric field caused by the potential of wirings is shielded by the layers 31. |
