Patent ID: 8173515

Claim:
A method for manufacturing a semiconductor device, the method comprising: forming a mask film on a semiconductor substrate; patterning the mask film to form a mask pattern; etching the semiconductor substrate by using the mask pattern as a mask, to form a trench; thermally oxidizing an inner wall of the trench, to form an oxide film; forming a liner film so as to cover the oxide film on the inner wall of the trench; depositing an SOD film over the trench and then carrying out a heat treatment to convert the SOD film into an SOD oxide film; processing the SOD oxide film to a predetermined height in the trench by (a) using the mask pattern as a stopper to carry out chemical mechanical polishing on the SOD oxide film and then etching back the SOD oxide film, or (b) etching back the SOD oxide film; removing the mask pattern and part of the liner film in contact with the SOD oxide film, to expose part of the SOD oxide film and form a gap in the trench; carrying out a heat treatment on the SOD oxide film; and filling an insulating film in the gap in the trench, to form an isolating region, wherein in forming the liner film, a first silicon nitride film, a silicon oxide film, and a second silicon nitride film are sequentially formed as the liner film on the semiconductor substrate, in forming the gap in the trench, part of the second silicon nitride film, as the liner film in contact with the SOD oxide film, is removed, and in forming the isolating region, an atomic layer deposition method is used to fill the insulating film.