Raman spectroscopy and microhardness of ion-implanted a-C:H-films

Optical and mechanical properties of a-C:H films subjected to carbon or nitrogen ion implantation (E=150 keV, D=1.1013−1.1017 cm−2) were studied. A correlation between hardness and Raman spectrum parameters of the films has been ascertained. After intermediate dose ion implantation (∼1016 cm−2) a drastic increasing of hardness and Young’s modulus of implanted films was observed. High dose implantation (1017 cm−2) results in appearance of structural inhomogeneities in the implanted region having extremely high hardness. The possible mechanisms of the effects observed are explained from the comparison of Raman and hardness data. ©