| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing flash memory device, with which the coupling ratio of a gate electrode can be improved. SOLUTION: This method is provided with processing for growing a tunnel oxide film 23 on a wafer 21 after a device isolation process, forming a nitride film 24 and a first polysilicon layer 25 thereon, forming a first dielectric film 26 on a surface after removing the first polysilicon layer 25, the nitride film 24 and the tunnel oxide film 23 in a floating gate forming part, exposing the wafer by removing the dielectric film on the surface of the wafer 21, forming a tunnel oxide film 27 at that exposed part, forming a polysilicon layer 28 for floating gate thereon and afterwards patterning that layer, exposing a first polysilicon layer 25 for control gate, forming a second dielectric film 26B at the upper part and the side part of the patterned polysilicon layer 28 for floating gate, and further forming a second polysilicon layer 29 for control gate and an antireflection film 31.
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