Current sensors using Fe-B-Nd-Nb magnetic metallic glass micro-cantilevers

We report on the development of MEMS current sensors composed of Fe67.5B22.5Nd6.3Nb3.7 (FBNN) magnetic metallic glass thin films. These current sensors are based on free-standing cantilever structures that benefit from the superior mechanical properties of the metallic glass, such as high fracture toughness and high yield strength. The resonant frequency of the proposed FBNN cantilever was 3.85 kHz in the fundamental flexure mode when the length, width and thickness of the cantilever were 750 mu m, 150 mu m and 3 mu m, respectively. A feed wire with a diameter of 500 mu m was placed close to the FBNN cantilever, and a downshift in the resonance peak was observed when the current intensity through the feed wire increased. The sensitivity of this frequency shift to the current intensity was 5.0 root Hz/A when the distance between the cantilever and the wire was 500 mu m. (C) 2015 Elsevier B.V. All rights reserved.