Simultaneous measurements of the magnetostrictive coefficient, Young's modulus, and Poisson ratio of thin films

A method, which determines simultaneously the magnetostrictive coefficient, Young's modulus, and Poisson ratio of a thin film utilizing the minimization of the total elastic energy of a cantilever film-substrate system, is suggested. An inaccuracy for the magnetostrictive coefficient, caused by assuming the elastic properties of the film as those of the corresponding bulk material, could be avoided and only a single elastic isotropic substrate is employed in the present method. The experimental data of an Fe-based amorphous thin film were analyzed by using the model. The calculated dependence of the magnetostrictive coefficient on the external magnetic field was compared with the experiment, and the discrepancy between both results were explained. The elastic properties of the film were also obtained.