Deposition of Amorphous CoZrNb Films Using CMF Magnetron Sputtering Technique

Abstract

Amorphous CoZrNb films with high saturation magnetization 4πMs of about 14 kG and low coercivity Hc of about 0.3 Oe have been successfully prepared by the CMF magnetron sputtering technique with a CoZrNb alloy target. Hc and 4πMs along the easy axis were changed by background pressure, film thickness and Ar pressure Pr. The applied voltage of discharge operation is as low as 270 V at Pr of 0.3 Pa. The maximum deposition rate is as large as 0.13 µm/min for a power density of 4.42 W/cm2. The target utilization efficiencies are improved in spite of using a magnetic target because a leakage magnetic field increases more to a greater extent by attaching an outer pole piece. These are about 95% and 60% in surface area and in volume, respectively. The changes in a film thickness of 1 µm deposited on the substrate were 0.05 µm at Pr of 0.2 Pa, and 0.06 µm at a distance of 50 mm between substrate and target, respectively.