An Integrated Circuit device, including: a base wafer including single crystal, the base wafer including a plurality of first transistors; at least one metal layer providing interconnection between the plurality of first transistors; a first wire structure constructed to provide power to a portion of the first transistors; a second layer of less than 2 micron thickness, the second layer including a plurality of second single crystal transistors, the second layer overlying the at least one metal layer; and a second wire structure constructed to provide power to a portion of the second transistors, where the second wire structure is isolated from the first wire structure to provide a different power voltage to the portion of the second transistors.