D0₂₂-Mn_2.6Ga thin films were fabricated by an ultra-high vacuum electron beam vapor deposition system on a MgO (100) single crystalline substrate with different buffer layer thicknesses (0.7 - 5 nm). As the annealing temperature T_a increased to 400℃, the squareness of the M-H curves improved, and the saturation magnetization M_s and magnetic anisotropy K_u increased. At that time, from XRD patterns, D0₂₂-Mn₃Ga (002) superlattice and (004) fundamental peaks were clearly observed from all samples. Our results suggest the existence of a magnetic dead layer of about 3.5 nm in the MnGa layer. Because of this magnetic dead layer, a relatively high K_u of 9.3 Merg/cm³ and low surface roughness R_a of 0.93 nm were obtained from Mn_2.6Ga thin film on a 2-nm Fe buffer at T_a = 400℃. The results in this work suggest that Fe is a suitable buffer layer for perpendicular magnetized D0₂₂-MnGa thin film.

  A small microstrip-line probe developed to measure the RF properties of magnetic materials for a wide frequency range has been successfully applied to the on-site permeability measurement of thin films on Si wafers. In this study it is applied to determine the saturation magnetostriction constants of films on Si wafers. The results suggest that on-site and simultaneous measurements of permeability and magnetostriction for films on Si wafers are possible.