Split-gate non-volatile memory cell having improved overlap tolerance and method therefor

Abstract

A method for forming a split-gate non-volatile memory (NVM) cell includes forming a first gate layer over a semiconductor substrate; forming a conductive layer over the first gate layer; patterning the first gate layer and the conductive layer to form a first sidewall, wherein the first sidewall comprises a sidewall of the first gate layer and a sidewall of the conductive layer; forming a first dielectric layer over the conductive layer and the semiconductor substrate, wherein the first dielectric layer overlaps the first sidewall; forming a second gate layer over the first dielectric layer, wherein the second gate layer is formed over the conductive layer and the first gate layer and overlaps the first sidewall; and patterning the first gate layer and the second gate layer to form a first gate and a second gate, respectively, of the split-gate NVM cell, wherein the second gate overlaps the first gate and a portion of the conductive layer remains between the first gate and the second gate.