MEMS Torsion Oscillator Magnetic Field Sensor

We developed a new sensitive microcantilever torque magnetometer-based magnetic field sensor that can detect magnetic field changes of a few nano-Tesla under ambient conditions. This sensor consists of a torsion oscillator, fabricated by a microelectromechanical systems (MEMS) process, and a soft magnetic Fe_77.5Si_7.5B₁₅ wire. This paper describes the principle and details of the experimental set-up and demonstrates that the sensitivity can be further improved by modifying the spring constant of the cantilever.