Structure and magnetic properties of FePd-alloy epitaxial thin films grown on MgO single-crystal substrates with different orientations

Abstract

FePd-alloy epitaxial films were prepared on MgO substrates of (100)B1, (110)B1, and (111)B1 orientations at a temperature of 600 °C by ultrahigh vacuum rf magnetron sputtering. The structural and the magnetic properties vary depending on the substrate orientation. L10–FePd(001) films are obtained on MgO(100)B1 substrates, whereas L10–FePd(101) films with the c-axis canted from the perpendicular direction are epitaxially grown on MgO(111)B1 substrates with six variants. FePd epitaxial films consisting of L10(100) and L10(112) crystals are formed on MgO(110)B1 substrates. A higher long range ordering parameter is obtained on the order of FePd/MgO(100)B1 > (110)B1 > (111)B1. The films grown on MgO(100)B1 substrates show perpendicular magnetic anisotropy, whereas the films grown on MgO(110)B1 and MgO(111)B1 substrates are easily magnetized in in-plane directions. The magnetization properties reflect the magnetocrystalline anisotropies of bulk L10–FePd crystal.