uv Studies of Tetrahedral Bonding in Diamondlike Amorphous Carbon

We report ultraviolet (uv) Raman scattering studies of hydrogen-free, diamondlike amorphous carbon thin films with a wide range of tetrahedral bonding. The uv Raman spectra are shown to provide direct evidence for the presence of s${\mathrm{p}}^3$-bonded C atoms in these materials. The experimental results are found to be in excellent agreement with theoretical predictions and contribute to an improved understanding of the mechanism by which the diamondlike fraction develops within the amorphous carbon network.