ION BEAM DEPOSITION OF LARGE-AREA LOW SCATTERING METAL COATINGS

METAL COATINGS DEPOSITED USING CONVENTIONAL EVAPORATION ARE UNSTABLE WHEN EXPOSED TO SUCH ELEMENTS OF THE ENVIRONMENT ASMOISTURE, HEAT, AND RADIATION. STATE-OF-THE-ART SPACE AND ASTRONOMICAL APPLICATIONS, SUCH AS WHITE-LIGHT, ALL- REFLECTING CORONOGRAPHS, REQUIRE COATINGS WITH OPTIMUM PROPERTIES. THESE APPLICATIONS REQUIRE LARGE-SIZE, SUPER- SMOOTH, HIGH-REFLECTANCE MIRRORS. ION-BEAM-BASED COATING TECHNIQUES HAVE SHOWN GREAT PROMISE TO IMPROVE THE DURABILITY AND REDUCE THE OPTICAL SCATTER OF THIN FILMS. METAL COATINGS WILL BE DEPOSITED USING CONVENTIONAL EVAPORATION, ION-ASSISTED DEPOSITION, AND ION-ASSISTED SPUTTERING. COATINGS OF SILVER, ALUMINUM, AND GOLD WILL BE EXAMINED. SEVERAL DIAGNOSTIC TECHNIQUES WILL BE EMPLOYED TOEXAMINE EFFECTS OF DEPOSITION CONDITIONS ON THE OPTICAL PROPERTIES, OPTICAL SCATTER, AND MECHANICAL PROPERTIES OF METAL COATINGS. SCALING OF THE COATING PROCESS TO COAT LARGE SURFACES WILL BE EXAMINED. METAL COATINGS ARE USEFUL FOR WIDE-BAND, HIGH-REFLECTANCE SURFACES, BANDPASS METAL-DIELECTRIC FILTERS, AND TELESCOPE MIRRORS AND SPACE-BASED OPTICAL TELESCOPES.