ISOLATION METHOD OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: An isolation method of a semiconductor device is provided to be capable of improving reliability and electrical property by minimizing leakage current. CONSTITUTION: After forming a nitride layer(20) on a semiconductor substrate(10), a trench(30) is formed in the semiconductor substrate. A spacer(40a) is formed at inner sidewalls of the trench(30). The spacer located on the bottom of the trench is selectively removed to expose the substrate(10). A vacancy is formed by isotropic etching of the exposed substrate. An oxide layer(60) is formed by thermal oxidation of the vacancy. Then, an insulating layer(70) is filled into the trench.