METHOD OF FORMING SHALLOW TRENCH ISOLATION IN A SEMICONDUCTOR SUBSTRATE

摘要

A method of forming shallow trench isolation in a semiconductor substrate. A hard mask having an opening is formed on the semiconductor substrate. The semiconductor substrate is etched through the opening to form a shallow trench. The semiconductor substrate is annealed in an ambient containing argon gas at a temperature of about 1150 to about 1200° C. for 1 to 2 hrs. An insulator is then formed on the hard mask to fill the shallow trench. The insulator is planarized while the hard mask is used as the polishing stop layer. Thereafter, the hard mask is removed to expose the upper surface of the semiconductor substrate and leave a shallow trench isolation.