2016 Volume 40 Issue 5 Pages 132-136
Y17Co83 and Gd17Co83 (at. %) alloy thin films are prepared on Cu(111) underlayers epitaxially grown on MgO(111) substrates at a substrate temperature of 500 °C by molecular beam epitaxy. The growth behavior and the film structure are investigated by in-situ reflection high-energy electron diffraction and X-ray diffraction. YCo5 and GdCo5 ordered alloy crystals epitaxially grow on the Cu underlayers. The epitaxial films consist of two (0001) variants whose orientations are rotated around the film normal by 30° each other. The epitaxial orientation relationships are (YCo5 or GdCo5)(0001) || Cu(111) (type A) and (YCo5 or GdCo5)(0001) || Cu(111) (type B). The volume ratios of two variants, Vtype A:VtypeB, in YCo5 and GdCo5 films are estimated to be 65:35 and 72:28, respectively. The long-range order degrees of YCo5 and GdCo5 films are respectively determined to be 0.63 and 0.65. These ordered alloy films show perpendicular magnetic anisotropies reflecting the magnetocrystalline anisotropies of YCo5 and GdCo5 crystals.