| 摘要 |
PROBLEM TO BE SOLVED: To restrain the deterioration of write speed of a flash memory by suppressing bird's beak generated in an interlayer film interposed between a floating gate and a control gate for a memory cell. SOLUTION: The interlayer film 4, interposed between a conductor film 3 for the floating gate and a conductor film 5 for the control gate, is constituted of a superposed film, having 4-layered structure consisting of a silicon nitride film 4a arranged at the lowermost layer, a silicon oxide film 4b, a silicon nitride film 4c and a silicon oxide film 4d. According to this method, the bird's beak of the silicon oxide film constituting one part of the interlayer film 4 can be suppressed, whereby deterioration of capacity of the interlayer film 4 can be restrained and a structure, capable of suppressing the deterioration of the writing speed, can be obtained. COPYRIGHT: (C)2003,JPO
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