Crystallization of amorphous Co2MnSi thin film

Amorphous Co2MnSi thin film was deposited using radio-frequency sputtering. The amorphous film crystallized into a single-phased L21 structure at 500 °C, which was highly disordered. The structure was meta-stable as the crystallized film decomposed upon further heating. Increasing the annealing temperature to 600 °C precipitated fcc Co together with Co2MnSi. Magnetic measurements showed that the as-deposited amorphous film was paramagnetic, exhibiting a spin glass state below 44 K. The phase transition at 500 °C produced a ferromagnetic Co2MnSi thin film whose saturation magnetic moment was considerably lower than reported values due to the disordered structure of the crystallized film.