Properties of physical vapor deposited diamond-like carbon films and the migration of hydrogen in H+ and 4He+ ion implanted and hydrogen co-deposited diamond-like carbon films were studied. Measurements utilizing Rutherford back-scattering spectrometry showed that the films studied have an average mass density of 2.6g/cm3. The bonding ratio sp3/sp2 was typically 70% measured with the electron spectroscopy for chemical analysis technique. Impurities and their depth distributions were deduced from the particle induced X-ray emission and secondary ion mass spectrometry measurements. Distributions of implanted and co-deposited hydrogen were measured by the nuclear resonance reaction1H(15N,αγ)12C and secondary ion mass spectrometry. It was found that annealing behavior of implanted H in diamond-like carbon had a diffusion-like character. The obtained diffusion coefficients resulted in the activation energy of 2.0eV. It was observed that in H co-deposited diamond-like carbon films the temperature of H release varied between 950 and 1070C depending upon the H concentration.

Hydrogen Migration in Diamond-Like Carbon Films. Vainonen, E., Likonen, J., Ahlgren, T., Haussalo, P., Keinonen, J., Wu, C.H.: Journal of Applied Physics, 1997, 82[8], 3791-6