Patent ID: 7304345
Filing Date: 2007-12-04
Classification: G11C,H01L

Abstract:
1. A semiconductor device comprising: first MISFETs constituting memory cells arranged in a first direction and in a second direction crossing to said first direction; and selective MISFETs, wherein each of said first MISFETs includes a floating gate electrode on a main surface of a semiconductor substrate through a first gate insulating film, a control gate electrode over an upper portion of said floating gate electrode through a first interlayer insulating film, and a pair of first semiconductor regions in said substrate and serving as source/drain regions, wherein said first MISFETs adjoining in said second direction are isolated by a first insulating film filled in a groove in said semiconductor substrate, wherein a selective MISFET, of said selective MISFETs, includes a first gate electrode formed with the same level layer as said floating gate electrode, a second interlayer insulating film formed with the same level layer as said first interlayer insulating film, a second gate electrode formed with the same level layer as said control gate electrode, and a pair of second semiconductor regions in said substrate and serving as source/drain regions, wherein said selective MISFET is arranged in said first direction adjacent to a first MISFET, of said first MISFETs, such that one of said pair of said second semiconductor regions of said selective MISFET is electrically connected to one of said pair of said first semiconductor regions of said first MISFET, wherein said selective MISFET includes a first region and a second region such that, at said first region, said second gate electrode is over an upper portion of said first gate electrode through said second interlayer insulating film, wherein, at said second region of said selective MISFET, said second interlayer insulating film is removed such that a bottom surface of said second gate electrodes at said second region is lower than an upper surface of said first gate electrode at said first region.