The mechanism of texture evolution in annealed L10-FePt thin films

The L1(0)-FePt thin films have been prepared by magnetron sputtering method and annealed at 400, 550, 600, and 700 degrees C for 30 min. The texture and microstructure of annealed L1(0)-FePt thin films have been investigated in this work. The texture was quantitatively investigated by X-ray diffraction (XRD). The microstructure was characterized by electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The experimental results indicated that the L1(0)-FePt phase was obtained at 550 degrees C via the disorder-order transformation, which has a great influence on the development of (001) fiber texture in FePt thin films. It is worth noting that the intensity of (001) fiber texture enhanced with the increase of temperature, but it weakened when the temperature raised to 700 degrees C. Correspondingly, there were a large number of twins in the 700 degrees C-annealed L1(0)-FePt thin films. Twinning will relax the in-plane strain and deflect the grain growth direction, which is one of the main reason for the decrease of (001) fiber texture at 700 degrees C.