Patent ID: 7598559

Claim:
A semiconductor storage device, comprising: a semiconductor layer having, at a surface portion thereof, a first conductivity type region and two second conductivity type regions separated from each other by the first conductivity type region; a memory function body formed on a surface of the semiconductor layer and having a function of storing electric charges; and a gate electrode provided above the first conductivity type region of the semiconductor layer, wherein the memory function body has a charge storage insulator having a function of storing electric charges, and a charge retention insulator positioned between the charge storage insulator and the semiconductor layer and having a function of retaining electric charges stored in the charge storage insulator, and wherein such impurity atoms as would cause an intrinsic semiconductor to be of the second conductivity type are present between the charge storage insulator and a preset depth location within the first conductivity type region of the semiconductor layer, wherein at least some of the impurity atoms are present in the charge retention insulator.