Non-volatile semiconductor memory device with improved performance

摘要

The non-volatile semiconductor memory device includes: a semiconductor substrate having a main surface; N<+> diffusion layers formed spaced from each other at the main surface of the semiconductor substrate; a floating gate formed on a region between the N<+> diffusion layers with a silicon oxide film interposed; an access gate formed adjacent to the floating gate on the region between N<+> diffusion layers with a silicon oxide film interposed; and a control gate formed on the floating gate with an interlayer insulating film interposed. The N<+> diffusion layer is provided between the floating gates, and another N<+> diffusion layer is provided between the access gates. Thus performance of a memory transistor in a non-volatile semiconductor memory device is improved, reliability of the device is improved and miniaturization of the device is facilitated.