High coercivity and high saturation magnetization Mn-Al thin films

Mn-Al thin films with the composition of 31-68 at.% Mn were prepared by rf magnetron sputtering at various substrate temperatures then annealed in vacuum. Effects of the chemical composition, substrate temperature and annealing temperature on the magnetic properties of Mn-Al films have been investigated. The analysis of X-ray diffraction and magnetic measurement indicate that τ-phase was synthesized at a composition range of 40-60 at.% Mn. However, the formation of large amount of τ-phase occurred for Mn₅₀-Al₅₀ films, which have a high coercivity up to about 3000 Oe and a fairly large saturation magnetization of about 420 emu/cc