Deposition of Co-Cr films for perpendicular magnetic recording by improved opposing targets sputtering

It is well known that Co-Cr films show a high perpendicular magnetic anisotropy, coercivity higher than 1000 Oe and other properties favorable for perpendicular magnetic recording media. In this report, Co-Cr films were prepared on polyimide films at high deposition rates in the range of 500-4000 Å/min using a new type of cathode sputtering apparatus with opposing targets. The deposition rate was 20 times as high as that attained by conventional RF sputtering. The composition of the deposited films was almost same as that of sputtered targets. The X-ray diffractometry indicated that the crystal of the film had hcp structure. The degree of c-axis orientation ΔΘ50was as low as 3.0° The prepared films 1 μm thick, deposited at the high rate of 4000 Å/min had magnetic properties suitable for perpendicular recording media, such as a perpendicular coercivity of 1100 Oe and an anisotropy magnetic field of 5.7 KOe.