MEMORY DEVICE AND PROGRAM METHOD THEREOF

摘要

PURPOSE: A flash memory device and a driving method thereof are provided to improve the performance of a storage system by applying a cache structure which is flexible than a nonvolatile cache using an existing NAND flash memory device. CONSTITUTION: A memory cell array comprises a plurality of memory cells. A control logic(160) executes a control operation for storing the information of one bit in the memory cell. Each memory cell is consecutively programmed without an erase operation. A multi-level cell saves data according to a program level. The program level is classified by a plurality of test voltages. The control logic executes a control operation which reads out the multi-level cell based on a plurality of test voltages in order to confirm the program level.