QUANTITATIVE CORRELATION OF INFRARED-ABSORPTION WITH NUCLEAR-MAGNETIC-RESONANCE MEASUREMENTS OF HYDROGEN CONTENT IN DIAMOND FILMS

Hydrogen concentrations in polycrystalline diamond films were found to correlate well with the integrated intensity of the CH-stretch region in the infrared (IR) spectrum for films with a total hydrogen content < 0.10 at. %. Comparison of IR to nuclear magnetic resonance (NMR) measurements yielded an effective absorption coefficient for the CH-stretch region of 4.3 +/- 0.8 X 10(3) lmol-1 cm-2, Similar to literature values for condensed-phase hydrocarbons. In several films, the dominant stretch modes occur at approximately 2850 and 2920 cm-1, typical of CH2 groups. The presence of these modes is accompanied by an increase in the Gaussian linewidth in the NMR spectrum, indicating a decrease in the interproton spacings within the film. In films with higher total hydrogen contents, a simple linear relationship between hydrogen content and intensity in the CH-stretch region is no longer applicable.