対向ターゲット式スパッタ法で作製した Co-Cr 膜の結晶配向に及ぼすバイアス電圧の効果

抄録

2000-Å thick Co₇₉Cr₂₁ films for hard disk media were deposited on glass substrates by using a facing targets sputtering (FTS) apparatus. RF power supply was used to apply a bias voltage to the substrate, where well-controlled ion bombardment could be applied. The change in the preferential orientation of Co-Cr crystallites, which was caused by biasing a growing film, was investigated. The bias effect caused a change in the preferential growth plane of hcp crystallite from (001) to (100). The easy magnetization direction changed from normal to in-plane, while the squareness (M_r/M_s)_// varied from 0.18 to 0.75. The in-plane coercivity H_c// had an almost constant value of about 250Oe, which was independent of the bias voltage.