Erasing and Programming methods of a flash memory device for increasing program speed of the flash memory device

摘要

The present invention relates to the deletion for the flash memory with a multi-level unit for improving program speed and programmed methods, delet method according to the present invention therefore be it is pre-programmed reduction voltage range wherein multi-level unit threshold voltage distribution, the ratio for multi-level unit occur can be reduced during deleting failure (failure), the threshold voltage distribution for improving level-cell can be reduced, and be executed at the entire program from procedure operation of a subsequent time. ;Preprogramming threshold voltage, voltage range, program circulation, step voltage