US Patent 7183153 Method of manufacturing self aligned non-volatile memory cells

A method of forming an array of non-volatile memory cells includes forming a plurality of floating gate structures and shaping the plurality of floating gate structures to reduce the width of upper parts of floating gate structures. A first process forms floating gates by etching an upper portion of a polysilicon structure with masking elements in place to shape the floating gate. A second process etches recesses and protrusions in a polysilicon structure prior to etching the structure to form individual floating gates.