Preparation and characterization of Ni–Mn–Ga high temperature shape memory alloy thin films using rf magnetron sputtering method

Ni53.97Mn25.67Ga20.36 high temperature shape memory thin film was deposited onto silicon substrates using radio-frequency magnetron sputtering. Crystallographic structure, surface morphology, compositions and martensitic transformation of Ni–Mn–Ga thin films were investigated by means of X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectrometry, and differential scanning calorimetry. The results show that Ni53.97Mn25.67Ga20.36 thin film with excellent surface quality is 7M structure at room temperature. The martensite transformation temperature Ms can be increased to 100 °C through selecting a suitable composition of the Ni–Mn–Ga target and appropriate sputtering parameters.