Semiconductor device comprising a memory cell group having a gate width larger than a second memory cell group

A semiconductor device comprising first and second nonvolatile memory elements formed over a semiconductor substrate,

• wherein the first nonvolatile memory element has:
• a first gate insulating film formed over the semiconductor substrate;
• a first gate electrode formed over the first gate insulating film;
• a first charge-storage film formed over the semiconductor substrate and over a side face of the first gate electrode;
• a second gate electrode formed over the first charge storage film,
• wherein the second nonvolatile memory element has:
• a second gate insulating film formed over the semiconductor substrate;
• a third gate electrode formed over the second gate insulating film;
• a second charge-storage film formed over the semiconductor substrate and over a side face of the third gate electrode;
• a fourth gate electrode formed over the second charge storage film,
• wherein the second and fourth gate electrodes are each in a form of a side wall;
• wherein a rewriting frequency of the second nonvolatile memory element greater than a rewriting frequency of the first nonvolatile memory element,
• wherein, in a gate width direction, a width of the fourth gate electrode is larger than a width of the second gate electrode, and
• wherein, in the gate length direction, a length of the second gate electrode is equal to a length of the fourth gate electrode.