PURPOSE: To enable high integration by enlarging the capacity of a memory cell for a plane area of the memory cell.

CONSTITUTION: A lower electrode 25 of a capacitor 28 and a conductive thin film 13 which is a shield electrode for element isolation in a field region 16 are partially opposed each other through a dielectric film 31 and the dielectric film 31 works as a capacitor dielectric film of the capacitor 28. Therefore, in the lower electrode 25, signal charge is stored not only in a surface in opposition to an upper electrode 27 through a capacitor dielectric film 26 but also in a surface in opposition to the conductive thin film 13 through the dielectric film 31.