Tetrahedral Amorphous Carbon With Ultratrace Hydrogen
In heat assisted magnetic recording (HAMR) where near-field light from a head heats up a disk, disk overcoat needs to be heat-resistive and transparent. ta-C (tetrahedral amorphous carbon) films have been considered to be promising for HAMR disk overcoat, because they are denser and harder than diamond-like carbon (DLC) films that have been used as disk overcoat. In the previous study, ta-C did not show any change in the film thickness by heating up to 450 degrees Celsius, approving a heat-resistant high protective film [1]. The purpose of this study is to investigate enhanced ta-C, which is harder, denser and higher-thermostability than those of conventional ta-C in reference to that nanometer-sized diamonds were more stable than graphite by adding the small amount of hydrogen [2]. In this report, ultratrace hydrogenerated ta-C, amorphous films, was investigated to expect similar effect as was observed in the crystalline films.