MANUFACTURE OF SELECTIVELY OXIDIZED MASK

摘要: PURPOSE:To prevent the decrease in drain withstand voltage by forming a resist film smaller than width of hole nitrided Si and polycrystalline formed pattern on an SiO2 substrate selectively oxidizing region which ions are injected with as mask. CONSTITUTION:A 13 oxidized 12 overall surface 11 14 larger 15 used to form due difference etching rates. Impurity from this hole, is removed, oxidized, element isolating 19 formed. In manner, stopper 18 becomes contained 19, thereby preventing without superposition narrow channel effect.