Methods of fabricating nonvolatile memory devices including bird's beak oxide

摘要

A nonvolatile memory device which suppress a drain coupling by minimizing an overlap capacitance between a floating gate and a drain. The nonvolatile memory device includes a cell array region in which a plurality of memory cells are two-dimensionally arranged and a peripheral circuit region for driving the memory cells. The memory cells comprise a first conductivity type semiconductor substrate, second conductivity type source and drain regions separated from each other with a channel region therebetween on the main surface of the semiconductor substrate, a gate oxide film formed on the upper portion of the channel region, a floating gate formed on the gate oxide film, an interlayer dielectric film formed on the upper portion of the floating gate, a control gate formed on the interlayer dielectric film, and a bird's beak area formed between the source/drain regions and the floating gate having greater thickness than the gate oxide film.