RTD/CMOS nanoelectronic circuits: thin-film InP-based resonant tunneling diodes integrated with CMOS circuits

The combination of resonant tunneling diodes (RTDs) and complementary metal-oxide-semiconductor (CMOS) silicon circuitry can offer substantial improvement in speed, power dissipation, and circuit complexity over CMOS-only circuits. We demonstrate the first integrated resonant tunneling CMOS circuit, a clocked 1-bit comparator with a device count of six, compared with 21 in a comparable all-CMOS design. A hybrid integration process is developed for InP-based RTDs which are transferred and bonded to CMOS chips. The prototype comparator shows sensitivity in excess of 10/sup 6/ VIA, and achieves error-free performance in functionality testing. An optimized integration process, under development, can yield high-speed, low power circuits by lowering the high parasitic capacitance associated with the prototype circuit.