HIGH TC FILMS FOR MICROWAVE APPLICATIONS

CVC PRODUCTS, INC., A MANUFACTURER OF VACUUM DEPOSITION EQUIPMENT PROPOSES TO DEVELOP SPUTTERED THIN FILMS OF HIGH-TC SUPERCONDUCTORS SUCH AS YBA2CU3O7, FOCUSING ON APPLICATIONS TO PASSIVE MICROWAVE CIRCUITS. THIS WORK WILL BUILD ON RECENT RESEARCH COLLABORATION BETWEEN CVC AND UNIVERSITY OF ROCHESTER. THE PRIMARY TECHNIQUE WILL BE RF MAGNETRON SPUTTERING OF REACTED OXIDES, USING A LARGE TARGETTHAT PERMITS UNIFORM DEPOSITION ACROSS 2-INCH SUBSTRATES. THIS PROCESS HAS PRODUCED HIGH-QUALITY SUPERCONDUCTING FILMSFOLLOWING A HIGH-TEMPERATURE ANNEAL, AND MORE RECENTLY USINGA MEDIUM-TEMPERATURE (630 DEGREES CENTIGRADE) IN-SITU PROCESS. USE OF A REACTION-BARRIER LAYER DEPOSITED ON SUBSTRATES SUCH AS A12O3, SI, AND GAAS SHOULD ALLOW SIMILIAR FILMS ON THESE AS WELL. THIN-FILM AG PADS MAKE GOOD LOW-LOSS CONTACTS, AND A SPUTTER-DEPOSITED DIELECTRIC OVERLAYER WILL ENHANCE ENVIRONMENTAL STABILITY. THE FILMS WILL BE PATTERNED INTO TRANSMISSION LINES AND STRIPLINE RESONATORS USING STANDARD PHOTOLITHOGRAPHY AND ETCHING. THEQ OF THE RESONATORS (AND THUS RF SURFACE RESISTANCE) WILL BEMEASURED AT FREQUENCIES UP TO 20 GHZ, OVER A WIDE RANGE OF TEMPERATURE, AND COMPARED TO THAT OF CONVENTIONAL COPPER LINES. THESE MICROWAVE PROPERTIES WILL BE CORRELATEDWITH DC ELECTRICAL MEASUREMENTS AND MATERIALS PROPERTIES.