Design and fabrication of a microelectromechanical system resonator based on two orthogonal silicon beams with integrated mirror for monitoring in-plane magnetic field

Abstract

We present a resonant magnetic field sensor based on microelectromechanical systems technology with optical detection. The sensor has single resonator composed of two orthogonal silicon beams (600 µm × 26 µm × 2 µm) with an integrated mirror (50 µm × 34 µm × 0.11 µm) and gold tracks (16 µm × 0.11 µm). The resonator is fabricated using silicon-on-insulator wafer in a simple bulk micromachining process. The sensor has easy performance that allows its oscillation in the first bending vibration mode through the Lorentz force for monitoring in-plane magnetic field. Analytical models are developed to predict first bending resonant frequency, quality factor, and displacements of the resonator. In addition, finite element method models are obtained to estimate the resonator performance. The results of the proposed analytical models agree well with those of the finite element method models. For alternating electrical current of 30 mA, the sensor has a theoretical linear response, a first bending resonant frequency of 43.8 kHz, a sensitivity of 46.1 µm T−1, and a power consumption close to 54 mW. The experimental resonant frequency of the sensor is 53 kHz. The proposed sensor could be used for monitoring in-plane magnetic field without a complex signal conditioning system.

3D Simulation-Based Acoustic Wave Resonator Analysis and Validation Using Novel Finite Element Method Software

“…While the design process of other microelectromechanical systems (MEMS) devices, like capacitive sensors [21][22][23], can take advantage of 3D FEM simulations to reduce the design cycle, AWRs have not benefited from 3D FEM simulations due to higher computational requirements, manufacturing complexity and lack of validation between measurements and simulation results. Three-dimensional simulations allow to develop techniques that confine energy on the resonator avoiding losses in the three axes by changing electrodes shape, adding frames, reducing anchor size, etc [24].…”

Analysis, design and optimization of compact ultra-high sensitivity coreless induction coil sensors

“…While more novel sensors like MEMS magnetic resonators are increasing in popularity, they cannot be employed here, since their operating principle is based on Lorentz forces that arise from the interaction of an internal field source with the external field [8,9]. This causes them to detect both DC and AC magnetic fields.…”