Advanced Magnetostrictive-Piezoresistive Sensor for Complex Magnetic Field Measurement

This paper presents a magnetic field sensor based on the coupling of the magnetostrictive-piezoresistive effect. The principle of this sensor is that when subjected to a spatial magnetic field, the magnetostrictive film undergoes strain. This strain can be transmitted to a closely coupled semiconductor silicon cantilever beam. By ion implantation in specific areas of the semiconductor silicon surface, the type and concentration of ion implantation can be controlled, thereby controlling the piezoresistive coefficient in that area. As a result, the strain in the semiconductor silicon can manifest as a change in resistance in the implanted region, allowing for the indirect measurement of magnetic field strength. Through finite element analysis, this paper reveals a strong linear relationship between the stress and strain experienced by the magnetostrictive film and the square of the magnetic field strength. Furthermore, it can be deduced that the change in resistance in the implanted region also exhibits a linear relationship with the square of the magnetic field strength. Therefore, this sensor demonstrates excellent linearity and holds significant potential for wide-ranging applications in online monitoring within the field of power systems.