Patent ID: 7449746
Filing Date: 2008-11-11
Classification: G11C,H01L

Abstract:
1. A memory structure comprising: a source region of a first conductivity type; a drain region of said first conductivity type; a first channel region of a second conductivity type opposite said first conductivity type, located adjacent said source region; a second channel region of said second conductivity type opposite said first conductivity type, located adjacent said drain region; a transfer channel region of said second conductivity type, located between said first and second channel regions; a first floating gate located above said first channel region; a second floating gate located above said second channel region; a first control gate located above said first floating gate and extending downward along one pair of side walls on opposite sides of the first floating gate in a first direction, serving as a steering element associated with said first floating gate; a second control gate located above said second floating gate and extending downward along one pair of side walls on opposite sides of the second floating gate in the first direction, serving as a steering element associated with said second floating gate; a third control gate located above said transfer channel region, serving as a control gate of an access transistor, said third control gate also overlying at least a portion of said first and second control gates and extending downward along another pair of side walls on opposite sides of each of the first and second floating gates in a second direction, the first and second directions being orthogonal with each other; a first tunneling dielectric layer positioned between at least said another pair of side walls of said first floating gate and said third control gate; and a second tunneling dielectric layer positioned between at least said another pair of side walls of said second floating gate and said third control gate, wherein the first and second floating gates are each in the shape of a T when viewed across the first direction.