Magnetoelastic Characteristics of the Multilayered Magnetostrictive Thin Film With Polyimide Substrate for Micro Actuator

摘要

In this paper, we have developed the flexible polyimide based magnetostrictive multibody actuators and investigated the magneto-mechanical characteristics of TbFe/Ni/TbFe layered thin film sputtered on the polyimide substrate with different thickness ratios for micro devices. The developed actuator is operated by magnetic field applied along with the length direction of each cantilever of the multibody design. In the fabrication process, micromachining techniques are adopted for the design of multicantilever shape of flexible polyimide substrate, thicknesses of 127 $mu$ m. And TbFe/Ni/TbFe multilayer films with thicknesses of 0.2/0.1/0.2, 0.1/0.1/0 $mu$m are sputter-deposited on the cantilever part of the actuator using designed mask (500 $mu$m thick) for selective dc magnetron sputtering. After the sputter process, X-ray diffraction studies are also carried out to determine the film structure and thickness of the sputtered film. As results, magnetization and magnetostriction of each actuator are measured, and discussed the results of external magnetic field lower than 0.5 T for micro-systems applications.