Nonvolatile semiconductor storage device and its manufacturing method

摘要: PROBLEM TO BE SOLVED: To lower the operating voltage of a nonvolatile semiconductor storage device and/or to increase speed by improving charge holding characteristic and, in addition, suppress secular changes characteristics device. SOLUTION: This contains storing layer CS having ability and has plurality dielectric films laminated upon active area SUB an electrode G provided on films. The includes first nitride film CS1 composed silicon or oxynitride second CS2 higher trapping density than has.