SEMICONDUCTOR MEMORY DEVICE AND METHOD FOR MANUFACTURING SEMICONDUCTOR MEMORY DEVICE

PROBLEM TO BE SOLVED: To provide a semiconductor memory device 3 which has a large storage capacity and high reliability, and to provide a method for manufacturing the semiconductor memory device 3. SOLUTION: The device includes: a plurality of first memory cells in which data of a 2Nvalue (N is a natural number of 2 or more) are stored; a plurality of second memory cells in which data of a 2Mvalue (M is a natural number smaller than N) is stored; and a CPU 11 which performs control of storing data in the second memory cells according to a first command, control of storing, in respectively one first memory cell, data in the respectively 2(N-M)second memory cells in which data of 2Mvalue are stored according to a second command, and control of erasing the data stored in the second memory cells. COPYRIGHT: (C)2011,JPO&INPIT