Effect of Ti (Cr) underlayer on the magnetic properties and microstructure of CoCrTa film for perpendicular magnetic recording media

C/CoCrTa/X (X = Cr, Ti) films were fabricated with DC facing target magnetron sputtering apparatus. Their magnetic properties and microstructure were characterized by vibrating sample magnetometer (VSM), X-ray diffraction (XRD), and scan probe microscope (SPM), respectively. The experimental results indicate that the Ti underlayer can induce the c-axis orientation of Co grain in the direction perpendicular to the film surface. For samples with Ti underlayer, the grain size and the surface roughness are relatively finer, and magnetic domains can be observed obviously. These results show that the sample with Ti underlayer is more suitable for the perpendicular magnetic recording media.