EPITAXIAL DIAMOND/CBN STRUCTURES AND DIAMOND FILMS

DIAMOND AND CUBIC BORON NITRIDE (CBN) SEMICONDUCTOR DEVICES HAVE THE POTENTIAL TO OPERATE AT HIGHER TEMPERATURE, HIGHER VOLTAGE, AT HIGHER FREQUENCY AND POWER AND UNDER MORE HARSH RADIATION ENVIRONMENT THAN CONVENTIONAL SEMICONDUCTORS, AND AS EMITTERS AND DETECTORS IN THE ULTRA-VIOLET AND VISIBLE. EPITAXIAL DIAMOND/CBN STRUCTURES HOLD THE POTENTIAL FOR FURTHER IMPROVEMENT OF THESE DEVICES AND FOR PROVIDING TUNABLE OPTICAL AND SEMICONDUCTING PROPERTIES. UNDER THE PHASE I PROGRAM, EPITAXIAL SINGLE CRYSTAL SEMICONDUCTING DIAMOND SUBSTRATES USING LOW PRESSURE CHEMICAL VAPOR DEPOSITION (CVD). ELECTRICAL RESISTIVITY AND ACTIVATION ENERGY HAVE BEEN MEASURED FOR A RANGE OF BORON DOPING CONCENTRATIONS, AT TEMPERATURES FROM ROOM TEMPERATURE TO 700C. SINGLE CRYSTAL DIAMOND FILMS CAN BE GROWN WITH VARIED THICKNESS AND DOPING LEVEL FOR DEVICE FABRICATION AND TESTING. EPITAXIAL DIAMOND SINGLE CRYSTAL FILMS HAVE ALSO BEEN GROWN ON CBN CRYSTALS. THE GROWTH OF SINGLE CRYSTAL CBN ON DIAMOND BY CVD IS UNDER CONTINUING INVESTIGATION.