Patent ID: 7368338

Claim:
A method of manufacturing a nonvolatile memory, comprising the steps of: polishing a surface of a substrate, thereby an average of a height difference between a convex and a concave of the surface being equal to or less than 5 nm; forming amorphous silicon films, including a first amorphous silicon film, and a second amorphous silicon film thicker than the first amorphous silicon film; forming semiconductor active layers, by activating the first amorphous silicon film and forming a first semiconductor active layer, and by activating the second amorphous silicon film and forming a second semiconductor active layer; forming a floating gate insulating film over the first semiconductor active layer, and forming a switching gate insulating film over the second semiconductor active layer; forming a floating gate electrode over the floating gate insulating film and forming a switching gate electrode over the switching gate insulating film; forming a control gate insulating film over the floating gate electrode; and forming a control gate electrode over the control gate insulating film.