Post-Processed Thin-Film GMI Magnetic Sensors

In this paper, a multilayer thin-film giant magnetoimpedance (GMI) magnetic sensor is fabricated, and its performance is enhanced by post-processing treatment. The CoSiB alloy is developed to enhance the performance of multilayer thin-film GMI sensors. The material is studied for different post-processing magnetothermal conditions. The provided recipe will facilitate low-cost fabrication of GMI structures in conventional microfabrication facilities. A detailed study is carried out to investigate the effect of temperature, time, and external magnetic field on the results of the post-processing technique. The prepared samples are tested with various magnetics and material characterization tools in order to give a detailed understanding of these effects. The post-processing shows a significant impact on the magnetic properties of the material. It is demonstrated that some nanoclusters of cobalt (with a diameter of 2-4 nm) form in its amorphous matrix structure, enhancing the permeability of the material.