Method of manufacturing semiconductor device

摘要

An object of the invention is to provide a semiconductor device having improved performance. A method of manufacturing a semiconductor device includes: forming a trench and then forming a first insulating film made of a silicon oxide film through CVD using a gas containing an O3 gas and a TEOS gas to cover the side surface of the trench with the insulating film; forming a second insulating film made of a silicon oxide film through PECVD to cover the side surface of the trench with the second insulating film via the first insulating film; and forming a third insulating film made of a silicon oxide film through CVD using a gas containing an O3 gas and a TEOS gas to close the trench with the third insulating film while leaving a space in the trench.

主权项

1. A method of manufacturing a semiconductor device, comprising the steps of:
(a) forming a trench portion in a main surface of a semiconductor substrate; (b) forming a first insulating film having a silicon oxide film in the trench portion and over the main surface of the semiconductor substrate by chemical vapor deposition with a first gas containing an ozone gas and a tetraethoxysilane gas; (c) forming a second insulating film having a silicon oxide film over the first insulating film by plasma chemical vapor deposition; and (d) forming a third insulating film having a silicon oxide film over the second insulating film by chemical vapor deposition with a second gas containing an ozone gas and a tetraethoxysilane gas, wherein in the step (b), the first insulating film covers therewith a first side surface of the trench portion, wherein in the step (c), the second insulating film covers therewith the first side surface of the trench portion via the first insulating film, and wherein in the step (d), the third insulating film closes therewith the trench portion while leaving a space in the trench portion.