Amorphous carbon overcoat for thin-film disk

The demand for higher areal densities in hard disks requires a lowering of the magnetic spacing between heads and media. To achieve this, the flying height of the slider and the thickness of the slider and media overcoats must be lowered. The overcoat thickness must be reduced while maintaining the durability and anti-corrosion properties. In this paper, we first focus on the material and tribological properties of sputtered hydrogenated amorphous carbon films, which are currently used for the overcoats of thin-film media. Then, we describe the plasma chemical vapor deposition technique for the next generation of overcoats. Finally, we describe a tetrahedral amorphous carbon overcoat deposited by filtered cathodic arc deposition, which will be used in future.