MANUFACTURING METHOD FOR ISOLATION STRUCTURE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing the element isolation structure is provided to improve the gap-filling property of a gap-filling insulating film by modifying the aspect ratio of a trench. CONSTITUTION: A trench(109) is formed in an element isolation region of a semiconductor substrate. A gate insulating film(103) and a conductive film are stacked on the active region of the semiconductor substrate. A poly-silicon film(113) is formed on the surface of the semiconductor substrate including the trench. A gap-filling insulating film is formed to fill the trench. The poly-silicon film and the gap-filling insulating film are oxidized.