Effect of current density on electroplated CoPt thick films

In this paper, we report on the influence of electrodeposition current density on the structural and magnetic properties of plated equiatomic CoPt magnetic thick films. Films are electroplated using constant current density, ranging 25-200 mA/cm², and subsequently annealed at 700°C for 40 min. It is found that electroplating current density has a strong influence over the plating rate, surface roughness, grain size, and order parameter. However, current density does not strongly affect the atomic composition of the plated film and only modestly influences the magnetic properties, namely coercivity. The films exhibit quasi-isotropic magnetic properties with the best results for a sample plated at 100 mA/cm², yielding H_ci = 900 kA/m, and in-plane squareness of 0.95 for a 3-μm-thick film having an rms surface roughness of 20 nm.