Adamopoulos, George and Godet, Christian and Robertson, John and Morrison, Neil (2004) Hydrogen content estimation of hydrogenated amorphous carbon by visible Raman spectroscopy. Journal of Applied Physics, 96 (11). pp. 6348-6352. ISSN 0021-8979
Full text not available from this repository.Abstract
In the present study, we report the hydrogen content estimation of the hydrogenated amorphous carbon (a-C:H) films using visible Raman spectroscopy in a fast and nondestructive way. Hydrogenated diamondlike carbon films were deposited by the plasma enhanced chemical vapor deposition, plasma beam source, and integrated distributed electron cyclotron resonance techniques. Methane and acetylene were used as source gases resulting in different hydrogen content and sp(2)/sp(3) fraction. Ultraviolet-visible (UV-Vis) spectroscopic ellipsometry (1.5-5 eV) as well as UV-Vis spectroscopy were provided with the optical band gap (Tauc gap). The sp(2)/sp(3) fraction and the hydrogen content were independently estimated by electron energy loss spectroscopy and elastic recoil detection analysis-Rutherford back scattering, respectively. The Raman spectra that were acquired in the visible region using the 488 nm line shows the superposition of Raman features on a photoluminescence (PL) background. The direct relationship of the sp(2) content and the optical band gap has been confirmed. The difference in the PL background for samples of the same optical band gap (sp(2) content) and different hydrogen content was demonstrated and an empirical relationship between the visible Raman spectra PL background slope and the corresponding hydrogen content was extracted.