Switching of magnetostrictive micro-dot arrays by mechanical strain

This paper investigates the switching behavior of magnetostrictive micro-dot arrays by mechanical strain. These amorphous FeCoBSi micro-dot arrays with diameters of 1-5 [micro]m and a thickness of 20 nm have been prepared on MEMS fabricated membrane structures. Magnetic force microscopy (MFM) has been used to obtain a spatially resolved switching behavior of these dots at different level of mechanical strain. For 20-nm-thick FeCoBSi dots, we have observed a strain induced switching starting at a level of about 0.04% of strain. In addition, finite-element simulations have been performed in order to correlate the MFM results with the local strain distribution of the membrane structure. Index Terms--Magnetostriction, micro-fabrication, strain sensors, thin films.