| 摘要 |
PROBLEM TO BE SOLVED: To increase the coupling ratio of cells, avoid the short-channel effect, and improve the controllability of a threshold for preventing the write-in failure. SOLUTION: The nonvolatile semiconductor memory cell comprises a semiconductor substrate 11, a laminate gate structure composed of a tunnel insulation film 12, and a gate side wall insulation film 40. The laminate gate structure comprises a floating gate electrode 13, an inter-electrode insulation film 20, and a control gate electrode 30. All these elements are laminated on the semiconductor substrate 11. Further, the inter-electrode 20 is configured of three-layered structure comprising a first oxidizer barrier layer 21, a middle insulation layer 22, and a second oxidizer barrier layer 23. The gate side wall insulation films 40 is formed on both sides of the laminate gate structure. The thickness of the gate side wall insulation film 40 increases toward the tunnel insulation film 12 from the inter-electrode insulation film 20 at the side of the floating gate electrode 13, and the width of the floating gate electrode 13 in the channel lengthwise direction decreases toward the tunnel insulation film 12 from the inter-electrode insulation film 20. COPYRIGHT: (C)2005,JPO&NCIPI
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