Forming an isolation film of semiconductor device by patterning pad film and predetermined depth of substrate to form trenches, and forming sidewall oxide films, first isolation film, silicon layer and second isolation film

摘要

Forming an isolation film of semiconductor device includes patterning pad film and predetermined depth of substrate to form trenches, forming sidewall oxide films on trench sidewalls, forming first oxide film and performing polishing to form first isolation film, removing pad film to expose substrate in active region, forming silicon layer on exposed substrate, and forming second oxide film and performing polishing to form second isolation film. Formation of an isolation film of semiconductor device includes forming a pad film on a semiconductor substrate (10), and patterning the pad film of predetermined region and predetermined depth of substrate to form trenches defining a non-active region and an active region; forming sidewall oxide films (18) on sidewalls of the trenches; forming a first oxide film for trench burial on the entire surface including the sidewall oxide films, and performing a polishing process until the pad film is exposed, forming a first isolation film (20); removing the pad film to expose the substrate in the active region; forming a silicon layer (21) having a height higher than that of the first isolation film on the exposed substrate in the active region; and forming a second oxide film for trench burial on the entire surface, and performing a polishing process until the silicon layer is exposed, forming a second isolation film (23). An isolation film in which the first and second isolation films are stacked is formed.