Effect of Pt seed on magnetic properties of Co-Pt alloy deposited into aluminum oxide pores

Summary form only given. Porous aluminum oxide layers were formed by anodizing 5N purity Al sheets in sulfuric acid at a constant voltage of 15 V. The Co-Pt alloy was deposited into the pores by pulse electroplating using a solution containing Co and Pt in a molar ratio of 100:1. The Co content of the deposited Co-Pt alloy increased with increasing pulse voltage V, from 76% at 5 V to 96% at 7 V. The perpendicular magnetization curves and coercivity were measured. X-ray diffraction measurements revealed that the c-axis of the hcp Co-Pt alloy, the easy axis of crystalline anisotropy, lies in the film plane without Pt seed. With an elongating Pt seed, the in-plane c-axis orientation becomes weaker and the perpendicular anisotropy due to shape becomes dominant.