Active microcantilevers based on piezoresistive ferromagnetic thin films

TL;DR

This paper introduces a novel self-sensing, self-actuating microcantilever system using FeGa ferromagnetic thin films that combine magnetostrictive actuation with piezoresistive readout, simplifying design and enabling remote sensing.

Contribution

It presents a new active microcantilever design utilizing FeGa thin films for combined actuation and sensing, reducing complexity compared to traditional piezoelectric-based systems.

Findings

Demonstrated piezoresistivity in FeGa thin films

Achieved self-actuation and sensing in microcantilevers

Potential for remotely actuated sensors

Abstract

We report the piezoresisitivity in magnetic thin films of FeGa and their use for fabricating self transducing microcantilevers. The actuation occurs as a consequence of both the ferromagnetic and magnetostrictive property of FeGa thin films, while the deflection readout is achieved by exploiting the piezoresisitivity of these films. This self-sensing, self-actuating micromechanical system involves a very simple bilayer structure, which eliminates the need for the more complex piezoelectric stack that is commonly used in active cantilevers. Thus, it potentially opens opportunities for remotely actuated, cantilever-based sensors.