MEMORY DEVICE AND SEMICONDUCTOR DEVICE

摘要

A memory device capable of increasing storage capacity per unit area while ensuring the maintenance period of data is proposed. A plurality of bit lines is divided into several groups, and a plurality of word lines is divided into several groups. A word line belonging to one of the groups is connected to a memory cell connected to a bit line belonging to one of the groups. The drive of the bit lines can be controlled in each group by a plurality of bit line driver circuits. Further, cell arrays are formed on a driver circuit including the bit line driver circuits and word line driver circuits. The driver circuit and the cell arrays are three-dimensionally formed so as to overlap with each other, thereby reducing the area occupied by the memory device even if a plurality of bit line driver circuits is disposed therein.