Vibration Readout of Microstructure Based on Inverse-Magnetostriction With an Integrated Hall Sensor

A vibration readout of a resonant structure based on inverse magnetostriction with an integrated Hall sensor is proposed. A bi-material FeGa/Si cantilever is fabricated using microfabrication, and the FeGa film is deposited by a novel electrodeposition method using an alkaline electrolyte. The deposited FeGa film consists of large crystal grains with a size of
$\sim $
500 nm and shows magnetostriction of 78.7 ppm at a magnetic field of 7.54 kOe. The bending of the cantilever changes the magnetization of the FeGa film due to the inverse magnetostriction effect. The integrated Hall sensor detects the changes in the magnetization of the FeGa film. The cantilever is vibrated near the resonance, and the output of the Hall sensor is observed to confirm the working principle of the vibration readout based on the inverse magnetostriction.