| 摘要 |
PURPOSE: A nonvolatile memory device and an erase operation controlling method thereof are provided to improve the reliability of the nonvolatile memory device by reducing the width of a threshold voltage distribution of erase cells. CONSTITUTION: A memory cell block for an erase operation is selected among a plurality of memory cell blocks. If an erase command is inputted, the selected memory cell block is erased(620). A first soft program is performed in the selected memory cell block if an erase operation passes(640). If the first soft program passes, a second soft program is performed in the selected memory cell block(680). [Reference numerals] (610) Inputting an erase command; (620) Executing erase; (630) Verifying erase ?; (640) Executing a first soft program; (650) Verifying a first soft program?; (660) Increasing Vb level; (670) Setting a second erase voltage level; (680) Executing a second program; (690) Verifying a second program?; (700) Increasing Vb level; (AA) Start; (BB) Finish
|
