A highly durable structure of carbon protective layer

Mechanical durabilities of carbon protective films for recording media were investigated by pin-on-disk tests. Chemical structures of carbon films were correlated with that of underlying metal films using X-ray photoelectron spectroscopy (XPS). It was found that the chemical structure of the carbon at the initial stage of deposition was influenced by the metal underlayers, resulting in different mechanical durabilities of the media. A Pt thin underlayer for a carbon layer promoted growth of a diamond-like carbon structure from the initial stage of deposition, making strong mechanical durability.