Patent ID: 9543314
Date: 2017-01-10
CPC Classifications: H01L

Claim:
1. A method of manufacturing a semiconductor device equipped with a memory cell of a nonvolatile memory, comprising the steps of: (a) providing a semiconductor substrate; (b) forming a first dummy gate electrode over the semiconductor substrate through a first insulating film; (c) forming in order a second insulating film having a charge accumulation part there inside, a first semiconductor film and a second semiconductor film each having a p-type conductivity type, so as to cover sidewalls of the first dummy gate electrode and the semiconductor substrate exposed from the first insulating film in adjacency to the sidewalls; (d) processing the first semiconductor film and the second semiconductor film to thereby form a second dummy gate electrode including the first semiconductor film and the second semiconductor film over the sidewalls of the first dummy gate electrode through the second insulating film; (e) forming a first interlayer insulating film so as to cover the first dummy gate electrode and the second dummy gate electrode; (f) polishing the first interlayer insulating film to expose the first dummy gate electrode and the second dummy gate electrode; (g) removing the second semiconductor film configuring the second dummy gate electrode, and the first dummy gate electrode; (h) forming a first gate electrode corresponding to a metal gate electrode for the memory cell in a first trench corresponding to a region from which the first dummy gate electrode is removed in the (g) step, and forming a metallic film in a second trench corresponding to a region from which the second semiconductor film is removed in the (g) step to thereby form a second gate electrode including the first semiconductor film and the metallic film for the memory cell.