A New High-Sensitivity Differential Z-Axis FM Accelerometer

SummaryIn this work, we propose an innovative high-performance Micro-Electro-Mechanical Systems (MEMS) z-axis Frequency Modulation (FM) accelerometer able to achieve a sensitivity higher than 1000 Hz/g around a carrier value of 180 kHz, with a 1120x608 µm
²
footprint only. The new device exploits the mechanical stiffness modulation induced on two in-plane flexural resonators by the torsional deformation of the two proof mass suspension springs to differentially measure an external z-axis acceleration. This concept, enabled by the Thelma-Double process by STMicroelectronics, is successfully demonstrated through preliminary experimental tests.