ESR Study of Elements Added-DLC Films Deposited by PBII and RF-CVD Methods
The element added diamond-like carbon films (hydrogen, fluorine, and sulfur) fabricated from C2H2:H2, C2H2:CF4 and C2H2:SF6 mixtures were used to study the effects of element contents on the spin density (ESR) and their relation to the changes in the structure of the DLC films deposited by PBII and RF-CVD method. The Raman spectroscopy was represented along with the ESR. The results indicate that the ESR spin density and g value of H-DLC, F-DLC, and S-DLC films deposited by PBII method decreases with element addition, attributed to the dangling bond was strongly observed after element addition. The Raman G peak position shifts towards higher, while the ID/IG intensity ratio increases with element addition and changes of bias voltage. For H-DLC films deposited by RF-CVD method, the spin density and g value decreases, the G peak shifts toward higher and ID/IG intensity ratio increases with hydrogen addition, that similar to H-DLC films deposited by PBII method. The ID/IG intensity ratio increases with hydrogen addition, indicating that the number of sp2 graphitic clusters of aromatic rings increases in the structure, and the decrease of spin density is correlated to the increase of the paramagnetic centers in the sp2-bonded graphite-like carbon structures, indicating to the spins originate mainly from the sp2 sites in the graphite-like carbon structures.
Pietro VINCENZINI and Ghislain MONTAVON
N. Moolsradoo et al., "ESR Study of Elements Added-DLC Films Deposited by PBII and RF-CVD Methods", Advances in Science and Technology, Vol. 66, pp. 41-46, 2010