SEMICONDUCTOR DEVICE MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To improve performance of a semiconductor device.SOLUTION: A semiconductor device manufacturing method comprises the steps of: forming a trench part TP and subsequently forming an insulation film IF1 composed of a silicon oxide film by a CVD method using a gas containing an Ogas and a TEOS gas to cover lateral faces of the trench part TP with the insulation film IF1; subsequently forming an insulation film IF2 composed of a silicon oxide film by a PECVD method to cover the lateral faces of the trench part TP with the insulation film IF2; and subsequently forming an insulation film IF3 composed of a silicon oxide film by a CVD method using a gas containing an Ogas and a TEOS gas to block the trench part TP by the insulation film IF3 leaving a space SP in the trench part TP.