An integrated three-dimensional micro-solenoid giant magnetoimpedance sensing system based on MEMS technology

摘要

In this paper, we proposed an integrated three-dimensional (3D) micro-solenoid giant magnetoimpedance (GMI) sensing system. The sensing system is composed by a 3D micro-solenoid inside which patterned Cobalt-based ribbon is kept as magnetic core and this system was fabricated by Micro-electromechanical Systems (MEMS) technology. The system was measured by non-contact method, which has the advantages of high sensitivity, low power consumption and widespread application prospect. The influence of external magnetic field direction and excitation frequency on micro-solenoid GMI sensing system has been discussed respectively. The fabricated system exhibits an optimum magnetoimpedance (MI) ratio of 4360 +/- 40 % at the excitation frequency of 13 MHz under longitudinal external magnetic field. In consequence, 3D micro-solenoid GMI sensing system offers great magnetic performance and this integrated sensing system has potential applications in the field of weak magnetic field detection. (C) 2019 Elsevier B.V. All rights reserved.