| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a nonvolatile semiconductor device that can improve erasure/writing durability of a nonvolatile semiconductor memory device, and can suppress degrading of the erasure/writing durability even when there is a memory cell due to gm degradation. <P>SOLUTION: There provided is a verify control circuit that, upon operation of verifying excessive writeback which determines whether a value satisfies an upper limit of a threshold voltage after erasure and writeback of selected memory cells to be erased, selects different memory cells in the same column in parallel and performs determination according to storage data of these selected memory cells. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
