| Popis: |
The Van de Graaff accelerator at Case Western Reserve University was used to study annealed diamond and diamondlike carbon films. Rutherford backscattering spectroscopy and elastic recoil detection analysis were used to characterize the as-deposited and annealed samples. The diamond films were deposited by microwave enhanced CVD while the diamondlike carbon films were deposited by plasma enhanced CVD and ion beam techniques. Included in the study were nitrogenated diamondlike carbon films. The samples were annealed inside the ion scattering chamber via a heated sample holder. The samples were annealed in a stepwise manner, beginning at room temperature and ending at 550°C. RBS and ERD spectra were simultaneously collected at each step in the annealing process. The compositional stability of the diamondlike carbon samples was determined. PECVD diamondlike carbon films remained stable up to 400°C, above which the hydrogen effusion was quite high. Nitrogenated diamondlike carbon films containing less than 10 atomic percent hydrogen remained stable up to 400°C while the hydrogenated samples were not stable above 200°C. A distinct hydrogen enriched surface region was observed on the diamond samples. This region disappeared upon annealing at 400°C and is most likely due to hydrogen containing adsorbates on the surface. The dynamics of this region were investigated and compared with secondary electron emission data on these samples. |
