Fabrication of MnAl thin films with perpendicular anisotropy on Si substrates

For the first time, perpendicularly magnetized L1(0)-ordered MnAl thin films were demonstrated using a MgO seed layer on Si substrates, which is critical to making spintronic devices. Fabrication conditions were selected by systematically varying sputtering parameters (film thickness, DC sputtering power, in situ substrate temperature, and post-annealing temperature) and investigating structural and magnetic properties. Strong perpendicular magnetic anisotropy with coercivity H-c of 8 kOe, K-u of over 6.5 x 10(6) erg/cm(3), saturation magnetization M-s of 300 emu/cm(3), and out-of-plane squareness M-r/M-s of 0.8 were achieved. These MnAl film properties were obtained via DC magnetron sputtering at 530 degrees C, followed by 350 degrees C annealing under a 4 kOe magnetic field oriented perpendicular to the film plane. (C) 2015 AIP Publishing LLC.