US Patent 7564088 High-density single transistor vertical memory gain cell

A memory cell which is formed on a substrate of a first conductivity type. A pillar of the first conductivity type extends vertically upward from the substrate. A source region of a second conductivity type is formed in the substrate extending adjacent to and away from a base of the pillar. A drain region of the second conductivity type is formed in an upper region of the pillar. A gate dielectric and conductor are arranged along a first side of the pillar. A capacitor dielectric and body capacitor plate are arranged along an opposite, second side of the pillar. A depletion region around the source region defines a floating body region within the pillar which forms both a body of an access transistor structure and a plate of a capacitor structure. The cell also provides gain with respect to charge stored within the floating body.