DENSIFICATION METHOD FOR TRENCH ISOLATION

摘要

PURPOSE: A densification method for trench isolation is to provide a gate oxide layer of which a quality is superior, by performing a densification process at a low temperature while guaranteeing a superior trench profile. CONSTITUTION: A trench of a predetermined depth is formed in a field region of a semiconductor substrate. The trench is filled with an insulating material. The surface of the insulating material is planarized, and the semiconductor substrate in an active region is exposed, to complete a trench isolation process. The resultant structure is pre-annealed at a temperature of 1000 deg.C and in a non-oxidizing atmosphere, and is annealed in a wet atmosphere.