System and method for providing process compliant layout optimization using optical proximity correction to improve cmos compatible non volatile memory retention reliability

Abstract

A system and method are disclosed for increasing retention reliability of a floating gate of a CMOS compatible memory cell. A mask structure is formed with a plurality of apertures near the edges of the mask structure. The size of the apertures is less than a resolution limitation of a photo exposure system. The mask structure is placed over a resist material and the resist material is exposed to light through the apertures of the mask structure. Zero order diffraction light passes though the apertures and imparts energy to the exposed portions of the resist material. A develop process is then used to remove portions of the resist material to form a sloped edge resist pattern. A sloped edge floating gate that is formed from the pattern facilitates the deposition of a thicker oxide layer at the sloped edge of the floating gate and reduces backend leakage current.