SEMICONDUCTOR MEMORY DEVICE AND BULK AREA FORMING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an improved sector structure in a nonvolatile semiconductor memory device. SOLUTION: In the nonvolatile semiconductor memory device for programming memory cells which have a first or a second logic status, and for deleting them in sector units in accordance with input data having a plurality of bit information, the memory cell transistors of cell array block and transistors of column decoder block have a plurality of sectors which are formed by sharing a bulk area, to provide a sector structure formed of the shared bulk.