Mbarek Sofiane Ben, Alcheikh Nouha, Ouakad Hassen M, Younis Mohammad I
Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia.
Mechanical and Industrial Engineering Department, College of Engineering, Sultan Qaboos University, Al-Khoudh, 123, PO-Box 33, Muscat, Oman.
Sci Rep. 2021 Nov 4;11(1):21634. doi: 10.1038/s41598-021-01171-z.
We present a highly sensitive Lorentz-force magnetic micro-sensor capable of measuring low field values. The magnetometer consists of a silicon micro-beam sandwiched between two electrodes to electrostatically induce in-plane vibration and to detect the output current. The method is based on measuring the resonance frequency of the micro-beam around the buckling zone to sense out-of-plane magnetic fields. When biased with a current of 0.91 mA (around buckling), the device has a measured sensitivity of 11.6 T, which is five orders of magnitude larger than the state-of-the-art. The measured minimum detectable magnetic field and the estimated resolution of the proposed magnetic sensor are 100 µT and 13.6 µT.Hz, respectively. An analytical model is developed based on the Euler-Bernoulli beam theory and the Galerkin discretization to understand and verify the micro-sensor performance. Good agreement is shown between analytical results and experimental data. Furthermore, the presented magnetometer is promising for measuring very weak biomagnetic fields.
我们展示了一种能够测量低场值的高灵敏度洛伦兹力磁微传感器。该磁力计由夹在两个电极之间的硅微梁组成，用于静电诱导面内振动并检测输出电流。该方法基于测量微梁在屈曲区域附近的共振频率来感测面外磁场。当通过0.91 mA的电流（在屈曲附近）偏置时，该器件测得的灵敏度为11.6 T，比现有技术高五个数量级。所提出的磁传感器测得的最小可检测磁场和估计分辨率分别为100 µT和13.6 µT/Hz。基于欧拉-伯努利梁理论和伽辽金离散化开发了一个分析模型，以理解和验证微传感器的性能。分析结果与实验数据显示出良好的一致性。此外，所展示的磁力计在测量非常微弱的生物磁场方面很有前景。
