| 摘要 |
The present technology includes the steps of: erasing a memory block connected to a source selection line, a plurality of word lines, and a drain selection line arranged in one direction; performing a soft program operation in the memory block which is erased; measuring the threshold voltage of a memory cell connected to the word line which is adjacent to the drain selection line and the threshold voltage of a memory cell connected to the word line which is adjacent to the source selection line among the word lines; and setting voltages to be applied to the word lines and the drain selection line according to the difference of the threshold voltages. [Reference numerals] (AA) Start; (BB) End; (S501) Erase a selected memory block; (S502) Selected memory block soft program; (S503) Measure a threshold voltage(Vn) of a memory cell connected to WLn and a threshold voltage(Vo) of a cell connected to WLo; (S504) Vn-Vo; (S505) Maintain Vdsl, maintain Vpass; (S506) Reduce Vdsl, maintain Vpass; (S507) Maintain Vdsl, reduce Vpass; (S508) Selected memory block program |
