METHOD OF PRODUCING FOR SEMICONDUCTOR MEMORY DEVICE

摘要

forming a silicon nitride film (2) and a CVD oxide film (3) on a Si substrate (1) to form a trench pattern by using a photomasking process; performing a reactive trench etching process on a mask with the trench pattern, forming a thermal oxide film (14) on the sidewall of the trench to apply a polysilicon film (5) thereon; etching the polysilicon film (5) to leave the lowr remaining polysilicon (6) formed on the V-shaped portion of the lower trench; removing the thermal oxide film (14) to form a P+ doping region thereon; and forming a dielectric film (15) for capacitor on the trench to form a polysilicon layer thereon to flat the surface of the trench; thereby forming an insulating layer on the edge of the V-shaped portion of the lower trench to prevent the capacitor dielectrics from deteriorating.