METHOD FOR MANUFACTURING ISOLATION LAYER OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming an isolation layer of a semiconductor device is provided to improve an isolation feature of the isolation layer by performing a heat treatment process in O2 atmosphere instead of N2 atmosphere. CONSTITUTION: An oxide layer(2) and a nitride layer(3) are formed on a semiconductor substrate(1). The oxide layer(2) and the nitride layer(3) are selectively removed by performing a masking process so as to form a trench(4). Then, a thermal oxide layer(5) is formed at a sidewall of the trench(4). The trench(4) is filled by an insulating layer(6). After a heat treatment process is performed in an O2 atmosphere, the insulating layer(6) is polished by a chemical and mechanical polishing(CMP) device until the nitride layer(3) is exposed.