Properties of Carbon Protective Films for Magnetic Disks

Carbon (graphite) film, which has a lubricating effect, was studied as a replacement for SiO2 film in protecting magnetic disks. Carbon films were formed by ion-beam sputtering, with stable amorphous films obtained regardless of the sputtering conditions. Carbon films had high scratch hardness and good thermal conductivity, as well as a higher wear resistance than SiO2. For sufficiently thin films, friction coefficients were small, enabling use as protective film for magnetic disks.