| 摘要 |
PURPOSE:To suppress a narrow channel effect phenomenon by forming a sectional sector-shaped film which narrows downwardly on an oxidation resistant film formed above a region for forming an element of a semiconductor substrate, implanting impurity ions with the sector-shaped film as a mask and forming a field oxidized film with the resistant film as a mask. CONSTITUTION:The entire surface of a silicon oxidized film 25 is etched to the surface of a photoresist film 24 with ammonium solution, thereby exposing the surface of the film 24. Subsequently, the film 24 is etched and removed, thereby forming a sectional sector-shaped silicon oxidized film 25 which narrows downwardly. Then, with the film 25 as a mask a silicon nitrided film 23 is etched and removed by a chemical dry etching method. Thereafter, with the film 25 as a mask channel stopper impurity (such as boron) ions are implanted to the surface of a substrate 21, thereby forming a p<+> type field inversion preventive region 26. |
