METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE

摘要

PURPOSE: A semiconductor device manufacturing method is provided to restrict the generation of grooves in an STI edge portion by further forming a dual structured polysilicon film with different oxidation rate between an anti-oxide layer and a pad oxide layer. CONSTITUTION: A pad oxide layer(102), a polysilicon layer and an anti-oxide layer are formed in sequence in an active area on a semiconductor substrate(100) to expose a field area. An exposed portion of the substrate surface is etched for a certain thickness to form a trench in the substrate. An oxidation process is performed to form the first insulation film(108) along the inner interface of the trench. A stress buffering film(110) is formed on the surface of the substrate(100). The second insulation film(112) is formed on the stress buffering film(110) to fill the trench. The second insulation film(112) is flattened to have the anti-oxide layer residing in the active area, and an STI is formed in the trench. The residual anti-oxide layer, the polysilicon layer and the pad oxide layer(102) are removed in sequence.