Abstract
We experimentally demonstrate a miniature highly sensitive wide-range resonant magnetic Lorentz-force micro-sensor. The concept is demonstrated based on the detection of the resonance frequency of an in-plane electrothermally heated straight resonator operated near the buckling point. The frequency shift is measured with optical sensing (laser) and the device is operated at atmospheric pressure. The frequency shift of the micro-sensor becomes very sensitive to any external disturbances around the buckling zone as indicated by the analytical model and experimental data, which show high sensitivity. The magnetometer demonstrates a measured sensitivity (S) of 33.9/T, which is very high compared to the state of the art. In addition, the micro-sensor shows a bi-linear behaviour with good linearity in two magnetic field regimes, low and high, with low power consumption around 0.2 mW. These attractive features make the proposed micro-sensor promising for various low-cost magnetic applications.
Highlights
In recent years, microelectromechanical systems (MEMS) have increasingly attracted the attention of researchers for various applications, such as filtering[1], signal processing[9], energy harvesting[10], and environmental sensors including magnetic, pressure[2,3,4], accelerometer[5], temperature[6], flow 7, and gas[8]
It can be observed that the resonance frequency decreases with the increase in ITh and reaches a minimum value around 0.27 mA, which corresponds to the buckling point
The results show that the resonance frequency dip is almost eliminated for high value of BZ (400 Magnetic range (mT)), which explains that the micro-beam experiences a high perturbed bifurcation due to the existence of magnetic field
Summary
Microelectromechanical systems (MEMS) have increasingly attracted the attention of researchers for various applications, such as filtering[1], signal processing[9], energy harvesting[10], and environmental sensors including magnetic, pressure[2,3,4], accelerometer[5], temperature[6], flow 7, and gas[8]. Magnetic field micro-sensors have been explored for various potential applications, such as magnetocardiography (MCG), magnetoencephalography (MEG), biomedical, inertial navigation systems, electronic compasses, telecommunications, and non-destructive testing[11,12,13,14,15]. These magnetic microsensors are mainly based on Lorentz force transduction. Note here that the straight micro-resonator takes advantage to high frequency shifting by operating around the buckling bifurcation at which the micro-beam is very sensitive to a small stiffness change. The concept is based on tracking the fundamental natural frequency of the electrothermally buckled straight micro-beam upon exposing it to a wide range of magnetic field
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
