Patent ID: 7098106

Claim:
A method of making mirror image non-volatile memory transistor pairs comprising: building a pair of spaced apart poly floating gate structures in a isolation region of a semiconductor substrate having a surface upon which said structures are built with a gap therebetween, each structure spaced from the substrate by tunnel oxide and having opposed sidewalls on opposite sides thereof; forming a pair of first subsurface electrodes adjacent sidewalls of the floating gate structures; disposing a first poly spacer spaced apart by tunnel oxide to a sidewall of each floating gate structure; after formation of the first poly spacers, forming a second subsurface electrode between the first subsurface electrodes; forming a second poly spacer in electrically contacting relation relative to a sidewall of each floating gate structure and electrically joined to a respective first poly spacer, the second poly spacer in contact relation joining a floating gate structure and a first poly spacer; forming a control gate in insulative relation over each floating gate structure.