Magnetically soft and high-saturation-magnetization FeCo films fabricated by co-sputtering

摘要

Magnetically soft FeCo films with high saturation magnetization were successfully obtained by co-sputtering Fe_(65)Co_(35) films onto a very thin Co_(93)Fe_7 seed layer. The coercivity of single FeCo films on the substrate was markedly reduced by increasing the deposition temperature and appropriately selecting the composition. The effect of composition and thickness of a high-Co-concentration Co_(100-y)Fe_y (0 ≤ y ≤ 11) seed layer on the magnetic properties and structure of Co_(100-y)Fe_y (0-10 nm)/Fe_(65)Co_(35) (100 nm) films was studied. It was observed that the texture of Fe_(65)Co_(35) films changed from (110) to (200) on using a Co_(100-y)Fe_y seed layer. The appearance of (200) texture and film growth with less lattice strain improved the soft magnetic properties of FeCo films. A double-layer Co_(93)Fe_7 (1 nm)/Fe_(65)Co_(35) (100 nm) film was obtained with saturation magnetization μ_0M_s = 2.4 T, easy-axis coercivity H_(ce) = 1 kA/m, hard-axis coercivity H_(ch) = 0.2 kA/m and anisotropy field H_k = 6.4 kA/m.