| 摘要 |
A method for erasing a NAND flash memory device is provided to prevent generation of erase fail resulting from change in threshold voltage due to repetitive program/erase cycling. According to a method for erasing a NAND flash memory device, an erase command is inputted(400). Data of a memory cell is erased according to the erase command(410). Erase state of the memory cell is verified using a first verify voltage(420). When the memory cell does not pass an erase verify step, an erase voltage is changed to a second verify voltage obtained by adding a certain voltage to the first verify voltage(440). Data of the memory cell is erased by applying an erase voltage to the cell not passing the erase verify step again. Erase state of a cell not passing the erase verify step is verified using a second verify voltage. |
