Patent ID: 8675416

Claim:
A method of performing a program verification operation of a flash memory device employing an incremental step pulse programming (ISPP) scheme, the method comprising: (a) setting a program loop count; (b) programming a selected memory cell according to the program loop count; (c) determining whether the program loop count satisfies a predetermined verification condition; (d) consecutively performing first verification and second verification on the selected memory cell if the program loop count satisfies the predetermined verification condition; (e) performing the second verification on the selected memory cell and skipping the first verification if the program loop count does not satisfy the predetermined verification condition; (f) determining a program pass or fail status of the selected memory cell; and (g) increasing the program loop count according to the program pass or fail status and repeating operations (b) through (e), wherein (d) is performed at least one time after (e).