Optimization of the Substrate Temperature for a Paramagnetic Steel Layer in a Co-Cr Perpendicular Recording Medium

摘要

Ferromagnetic Co_(77)Cr_(20)Ta_3 layers weredeposited on paramagnetic Co_(65)Cr_(35) and Pt seed layers.The crystallographic and magnetic characteristics of the Co-Cr-Ta layer were improved by independently adjusting the substratetemperature T_s of the Co_(65)Cr_(35) seed layer in the range150 deg C - 200 deg C. The Pt seed layer results in better c-axisorientation even at a low T_s of around 250 deg C, and a 50-nm-thick Co-Cr-Ta layer deposited on it exhibited a highperpendicular coercivity H_(c perpendicular) of 2.5 kOe at aT_s of 250 deg C. Optimization of T_s for the paramagnetic Co-Cr layer and use of the Pt seed layer were effective fordepositing ultra-thin Co-Cr-Ta recording layers.