METHOD FOR MANUFACTURING MOS TRANSISTOR

摘要

PURPOSE: A method for manufacturing MOS transistor is provided to improve an operation characteristic by forming a thermal oxidation film to a side surface substrate of a gate and forming a high density source and drain by a diffusion. CONSTITUTION: A gate(2) on which a nitration film(3) is deposited is formed on a semiconductor substrate(1). A low density impurity ion is injected to a lower portion of a side substrate of the gate(2) and a low density source and drain(4) is formed. A nitration side wall(5) is formed to the side wall of the gate(2) and the low density source and drain(4) is etched at a certain depth. A side wall of an oxidation film is formed to a side surface of the nitration side wall(5) and a tungsten silicide is formed on an upper portion of the low density source and drain(4). The side wall of the oxidation film is selectively removed and a part of region of the low density source and drain(4) is exposed, and a diffusion preventing film is formed to a part of region of the low density source and drain(4).