ELEMENT ISOLATION FILM FORMATION METHOD FOR SEMICONDUCTOR MEMORY ELEMENT

摘要

PROBLEM TO BE SOLVED: To provide an element isolation film formation method for a semiconductor memory element for saving process costs, and for improving the reliability of elements. SOLUTION: This element isolation film formation method includes a step of forming a tunnel isolation film and a charge accumulation layer on a semiconductor substrate; a step of forming a trench for element isolation by etching the charge accumulation layer and the tunnel isolation film; a step of forming a protection film on a whole structure including the trench for element isolation; a step of forming the first isolation film on the bottom face of the trench for element isolation; a step of removing the oxidized section of the protection film in the step of forming the first isolation film; and a step of forming a second isolation film on the whole structure including the first isolation film. COPYRIGHT: (C)2009,JPO&INPIT