Nonvolatile semiconductor memory device

摘要

Binary mode memory cells each storing data of a single bit per cell and multilevel mode memory cells each storing data of multi bits per cell are allocated with different address regions in a fixed manner and are formed in different regions. According to the fixed address allocation, the binary mode memory cells and the multilevel mode memory cells can be optimized individually and separately. In this way, the reliability of a nonvolatile semiconductor memory device is improved and the area occupied by the memory arrays is reduced.