Role of film thickness on magnetic properties of sputter deposited Co2FeGa alloy thin films

We report the role of film thickness on the structure, microstructure and magnetic properties of Co2FeGa thin films. The grain size was observed to increase with increase in film thickness. An in-plane magnetic anisotropy was observed for all the films. A gradual increase in saturation magnetization (M-s) and a nearly constant coercivity (H-c) was observed in the films with thickness > 10 nm at room temperature. Curie temperature (T-C) was found to increase gradually with increase in film thickness which is attributed to the increase in grain size with the film thickness. Thermal stability of the films was studied from the temperature dependent magnetic hysteresis loops which exhibit nearly a constant value of M-s till 873 K for all the films. This evidences the high temperature stability of Co2FeGa thin films. The increase in H-c at higher temperatures is attributed to the diffusion of Si into the film.