RAMAN-SCATTERING AND HYDROGEN-CONTENT ANALYSIS OF AMORPHOUS HYDROGENATED CARBON-FILMS IRRADIATED WITH 200-KEV C+ IONS

Amorphous hydrogenated diamondlike carbon films (a-C:H) have been modified by bombardment with 200-keV C+ ions at four doses ranging from 1014 to 1017 cm-2. Ratios of carbon to hydrogen in the resulting samples have been determined with use of elastic recoil detection (ERD) and Rutherford backscattering (RBS); hydrogen content is significantly reduced as the dose is increased. Raman scattering data indicate increasing graphitization with increasing ion dose. These data have been analyzed to determine position and width of previously observed G and D lines. Raman scattering results obtained for a-C:H films annealed at temperatures up to 800°C indicate that C+-ion bombardment and high-temperature annealing of a-C:H films have a similar effect on their structure. Data obtained from all of the measurement techniques cited above indicate that the major changes occur in the a-C:H films implanted with doses of 1016 cm-2 or greater. © 1990 The American Physical Society.