Magnetic properties of TbFeCo films with Au underlayer for perpendicular magnetic recording

摘要

W/Tb_(32)Fe_(51)Co_(17)/Au films with perpendicular anisotropy were prepared on thermally oxidized Si substrates by DC magnetron sputtering. The deposition temperature of Au underlayer was varied from room temperature to 500℃ in order to control surface morphology. SEM results show Au underlayers transfers from continuous structure to convex grain structure when deposition temperature is higher than 200 ℃. Compared with TbFeCo films deposited on continuous Au underlayer, TbFeCo films prepared on convex grain structured Au underlayer show much enhanced coercivity and reduced domain size. The coercivity of TbFeCo films decreases with reducing Au convex grain size, which can be understood by exchange interaction dependence of Au convex grain size based on MFM measurement results. Angular dependence of coercivity measurement shows the magnetization reversal of TbFeCo films on convex grain structured Au underlayer follows a Stoner-wohlfarth rotation mode. Our results indicate the TbFeCo film with Au underlayer a good candidate for high density perpendicular magnetic recording.