Patent ID: 9460929
Filing Date: 2016-10-04
CPC Classification: H01L

Claim Text:
1. A method of manufacturing a semiconductor device including 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 via a first insulating film; (c) forming a first gate electrode for the memory cell over the semiconductor substrate via a second insulating film having an internal charge storage portion such that the first gate electrode for the memory cell is adjacent to the first dummy gate electrode; (d) forming a first interlayer insulating film so as to cover the first dummy gate electrode and the first gate electrode therewith; (e) polishing the first interlayer insulating film to expose the first dummy gate electrode; (f) after the step (e), removing the first dummy gate electrode; and (g) forming a second gate electrode for the memory cell in a first trench as a region resulting from the removal of the first dummy gate electrode in the step (f), wherein the second gate electrode is a metal gate electrode, wherein a height of the first gate electrode formed in the step (c) is lower than a height of the first dummy gate electrode, and wherein, in the step (e), the first gate electrode is not exposed.