Effect of a Ti Seed-Layer on the Magnetic Properties of CoCrTa/Ti/CoZrNb Perpendicular Recording Media

Abstract

The effect of a Ti seed-layer on the magnetic properties and microstmctures of CoCrTa was studied in CoCrTa/Ti/CoZrNb double-layered perpendicular recording media. It was revealed that a thin Ti film of 5 nm, deposited at a substrate temperature of 230°C, gave the most enhanced c-axis alignment perpendicular to the film plane, showing the greatest perpendicular anisotropy. This large anisotropy yielded the best magnetic and recording properties under the present experimental conditions. The read-back amplitude at this Ti thickness was 3 times larger than that without the Ti layer, resulting in a higher ratio of signal to media noise. There was no significant loss in recording resolution due to the non-magnetic Ti space between the CoCrTa recording layer and the CoZrNb underlayer.