ATOMIC LAYER CVD OF YBACUO OVER A LOW DIELECTRIC SUBSTRATE

WE PROPOSE THE DEPOSITION OF HIGH TC YBACUO LAYERS, USING ATOMIC LAYER CVD OVER A COMPOSITE ALXGA1-XAS/ALXGA1-XN/SAPPHIRE SUBSTRATE. THE UNIQUE ATOMIC LAYER PROCESS IS EXPECTED TO REDUCE THE EPITAXY TEMPERATURE WELL BELOW THAT REQUIRED FOR CONVENTIONAL MOCVD. THIS WILL ELIMINATE THE NEED FOR A POST DEPOSITION ANNEAL. OUR SUBSTRATE STACK IS ALSO UNIQUE. IT HAS A DIELECTRIC CONSTANT MUCH LOWER AND THERMAL CONDICTIVITY AND MECHANICAL STRENGTH MUCH SUPERIOR THAN GAAS. PHASE I EFFORT WILL THEREFORE LEAD TO A MULTILAYER STACK WELL SUITED FOR FABRICATION OF HIGH FREQUENCY LOW LOSS MMIC CIRCUITS WITH SUPERCONDUCTOR ELECTRODES. THE SIX MONTH PHASE I PROGRAM WILL SIGNIFICANTLY BENEFIT FROM OUR RELATED WORK ON HTC SUPERCONDUCTOR DEPOSITION AND SINGLE CRYSTAL MULTILAYER ALXGA1-XAS/ALXGA1-XN DEPOSITIONS OVER SAPPHIRE SUBSTRATES. THE RESULTING FILMS WILL BE CHARACTERIZED FOR THEIR SUPERCONDUCTING TRANSITION TEMPERATURES. PHASE II WILL FOCUS ON THE FABRICATION OF INTEGRATED MMIC DEVICES.