METHOD FOR FABRICATING ISOLATION LAYER OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating an isolation layer of a semiconductor device is provided to improve yield and productivity simultaneously by improving an insulation characteristic of the isolation layer, a step coverage and a filling characteristic. CONSTITUTION: A pad insulation layer(M) is formed on a substrate(20). The substrate is selectively etched to form a trench by using the pad insulation layer as an etch mask. A fluid insulation layer(23) is formed along the profile of the trench by using reaction source including nitrogen. A densifying insulation layer(24) is formed on the fluid insulation layer to fill the trench. A planarization process is performed on the densifying insulation layer and the fluid insulation layer until the surface of the pad insulation layer is exposed, so that the densifying insulation layer and the fluid insulation layer constitute the isolation layer(ISO) of a stacked structure in the trench.