Patent ID: 7601635
Filing Date: 2009-10-13
Classification: H01L

Abstract:
1. A manufacturing method of a semiconductor device having a nonvolatile memory cell, comprising the steps of: (a) forming a first insulating film over a semiconductor substrate; (b) forming a first polycrystalline silicon film over the first insulating film; (c) forming a second insulating film over the first polycrystalline silicon film; (d) forming a second polycrystalline silicon film over the second insulating film; (e) forming an W (f) after the step (e), patterning the W (g) after the step (f), performing heat treatment, wherein the step (d) comprises steps of: (d1) forming a second region of the second polycrystalline silicon film over the second insulating film; and (d2) forming a first region of the second polycrystalline silicon film over the second region of the second polycrystalline silicon film, an impurity concentration of the first region of the second polycrystalline silicon film being smaller than that of the second region of the second polycrystalline silicon film, wherein, in the step (e), the W wherein the W