US Patent 7402866 Backside contacts for MOS devices

A semiconductor structure includes a semiconductor substrate having a first surface and a second surface opposite the first surface, a gate dielectric over the first surface of the semiconductor substrate, a gate electrode over the gate dielectric, a source/drain region having at least a portion in the semiconductor substrate, a dielectric layer having a first surface and a second surface opposite the first surface wherein the first surface of the dielectric layer adjoins the second surface of the semiconductor substrate, and a contact plug in the dielectric layer, wherein the contact plug extends from a bottom side of the source/drain region to the second surface of the dielectric layer.