| 摘要 |
PURPOSE:To form the shape of the transistor, which displays an effect to the increase of the degree of integration and sub-threshold characteristics thereof are excellent, by forming a gate electrode, through which a field oxide film is formed to a swelled shape more than an element forming region, and removing only the gate electrode on an element isolation region through sputtering etching. CONSTITUTION:A resist film is applied on the surface of a substrate 11, and etched while leaving the element forming region. Silicon is removed selectively through anisotropic etching technique while using the residual resist film as a mask to form a groove to a field region. A resist 15 is applied on the whole surface to flatten the surface, and a resist 14, the resist 15 and an insulating film 13 are etched under conditions, through which etching rates for the resists 14, 15 and the film 13 are equalized, through a reactive on etching method. Corners and inclined planes are etched at rates faster than others by sputtering-etching polysilicon. When sputtering etching is continued, only polysilicon on the element isolation region is removed through etching, and a flat surface shape is obtained. |
