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.