METHOD FOR FORMING ISOLATION LAYER TO SHORTEN PROCESS TIME

摘要

PURPOSE: A method for forming an isolation layer is provided to be capable of shortening process time and improving reliability of a semiconductor device. CONSTITUTION: A hard mask pattern(104) is formed on a semiconductor device(100). A trench(102) is formed in the substrate by using the hard mask pattern as a mask. By oxidizing the resultant structure, the first oxide layer(108a) is formed at inner walls and bottom of the trench, and the second oxide layer is simultaneously formed on the hard mask pattern. By wet etching of the resultant structure, the second oxide layer is removed and the outside portion of the first oxide layer is partially removed.