Patent ID: 9299854
Filing Date: 2016-03-29
CPC Classification: H01L

Claim Text:
1. A method for manufacturing a semiconductor device, comprising the steps of: (a) preparing a semiconductor substrate; (b) forming a first insulating film in a first region on a first principal surface side of the semiconductor substrate and in a second region on the first principal surface side of the semiconductor substrate, on the first principal surface of the semiconductor substrate; (c) forming a first conductive film over the first insulating film in the first region and in the second region; (d) removing the first conductive film in the first region and leaving the first conductive film in a part of the second region; (e) forming a second conductive film on the first principal surface of the semiconductor substrate including over the first conductive film that is left in the step (d), in the first region and in the second region; (f) patterning the second conductive film in the first region, and leaving, in the second region, the second conductive film over the first conductive film so that an outer peripheral portion of the first conductive film that is left in the step (d) is covered with the second conductive film; (g) after the step (f), oxidizing a surface of the second conductive film; and (h) after the step (g), in the second region, patterning the second conductive film, the first conductive film, and the first insulating film, to thereby form a first film portion formed of the first insulating film, a second film portion formed of the first conductive film over the first film portion, and a third film portion formed of the second conductive film over the second film portion.