Effect of thin carbon layer insertion on the magnetic property and microstructure of CoCrPt/Ti hybrid recording media

CoCrPt/Ti/C, CoCrPt/C/Ti and CoCrPt/C/CoCrPt/Ti thin film were prepared to study the effect of thin C layer insertion on the magnetic properties and microstructure of CoCrPt/Ti hybrid recording media. Surface roughness improvement and C atoms' diffusion to Ti underlayer contribute to optimized magnetic properties in CoCrPt/Ti/C films due to C seedlayer insertion. Very thin C intermediate layer gives rise to smaller magnetic grain size and improved perpendicular coercivity in annealed CoCrPt/C/Ti thin film while thicker C intermediate layer hinders the epitaxial growth relationship between Ti underlayer and Co-alloy magnetic layer. 3nm C intermediate layer in CoCrPt/C/CoCrPt/Ti thin film structure helps to obtain smaller grain size and weaker inter-granular exchange coupling interaction in the magnetic layer after annealing process. C atoms' diffusion into Ti underlayer, Co-alloy magnetic layer or grain boundary in magnetic layer plays an important role in the effect of thin C layer insertion on the magnetic property and microstructure of CoCrPt/Ti hybrid recording media.