Xeを用いたスパッタリングによる大飽和磁化Baフェライト薄膜の作製と磁気特性

抄録

Ba ferrite films were deposited epitaxially on ZnO underlayer from targets with composition of BaO.6.5Fe₂O₃ using the facing targets sputtering apparatus. The gas mixture of Ar and Xe at 0.18 Pa and O₂ at 0.02 Pa was used as the sputtering gas and the dependences of crystallographic and magnetic characteristics on the partial Xe pressure Pxe (0.0-0.18 Pa) were investigated. Films deposited at various Px5 and at substrate temperature of 600°C were composed of BaM ferrite and spinel crystallites, and the minimum centerline average roughness R_a of 8.9 nm was obtained at Pxe of 0.10 Pa and then the saturation magnetization 4πM_s, of 5.1 kG and perpendicular anisotropy constant Ku1 of 4.23 × 10⁵ J⋅m^-3 were larger than those of bulk BaM ferrite of 4.8 kG and 3.30 × 10⁵ J⋅m^-3, respectively. C-axis orientation was observed even for the film deposited at low T_s of 475°C and 4πMs, perpendicular and in-plane coercivity, Hc_⊥and H_c//, were 4.7 kG, 2.38 and 0.19 kOe, respectively.