Flash memory devices that utilize age-based verify voltages to increase data reliability and methods of operating same

摘要

Disclosed is a method of verifying a programmed condition of a flash memory device, being comprised of: determining a level of an additional verifying voltage in response to the number of programming/erasing cycles of memory cells; conducting a verifying operation to programmed memory cells with an initial verifying voltage lower than the additional verifying voltage; and selectively conducting an additional verifying operation with the additional verifying voltage to the program-verified memory cells in response to the number of programming/erasing cycles.