Substrate Bias Effects on Magnetic and Structural Properties of ${L1}_{0}$ -FePt Based Recording Media

In this paper, a method to improve the magnetic and structural properties of heat-assisted magnetic recording media by applying partial substrate bias during the deposition of FePt-based recording layer is demonstrated. Although the application of a substrate bias for the entire FePt layer deposition deteriorated the media properties, improvements were noted when a substrate bias is selectively applied for the deposition of top portion of the FePt layer. Our experiments suggest that the compressive stress due to the ion peening in the biased deposition degrades the texture and magnetic properties of the FePt media, primarily during the initial phase of FePt film growth. On the other hand, the media fabricated by applying an optimum substrate bias for the deposition of top portion of the FePt layer showed improvements in the micro-structural and magnetic properties.