A double barrier resonant tunneling diode (RTD) is formed and integrated with a level of CMOS/BJT/SiGe devices and circuits through processes such as metal-to-metal thermocompressional bonding, anodic bonding, eutectic bonding, plasma bonding, silicon-to-silicon bonding, silicon dioxide bonding, silicon nitride bonding and polymer bonding or plasma bonding. The electrical connections are made using conducting interconnects aligned during the bonding process. The resulting circuitry has a three-dimensional architecture. The tunneling barrier layers of the RTD are formed of high-K dielectric materials such as SiO₂, Si₃N₄, Al₂O₃, Y₂O₃, Ta₂O₅, TiO₂, HfO₂, Pr₂O₃, ZrO₂, or their alloys and laminates, having higher band-gaps than the material forming the quantum well, which includes Si, Ge or SiGe. The inherently fast operational speed of the RTD, combined with the 3-D integrated architecture that reduces interconnect delays, will produce ultra-fast circuits with low noise characteristics.