Wang Chen, Wu Xinyu, Sadeghpour Sina, Shojaeian Milad, Wang Linlin, Madeira Bernardo Pereira, Guan Yangyang, Liu Huafeng, Wang Yuan, Zhang Pan, Mak Pui-In
ESAT-MNS, University of Leuven, Leuven, 3001, Belgium.
PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, PR China.
Microsyst Nanoeng. 2025 Apr 16;11(1):64. doi: 10.1038/s41378-025-00910-w.
This paper describes a novel, system-level design methodology based on a genetic algorithm (GA) using freeform geometries for microelectromechanical systems (MEMS) devices. The proposed method can concurrently design and co-optimize the electronic and mechanical parts of a MEMS device comprising freeform geometries to achieve a better system performance, i.e., a high sensitivity, a good system stability, and large fabrication tolerances. Also, the introduction of freeform geometries allows higher degrees of freedom in the design process, improving the diversity and potentially the performance of the MEMS devices. A MEMS accelerometer comprising a freeform mechanical motion preamplifier in a closed-loop control system is presented to demonstrate the effectiveness of the design approach. The optimization process shows the main figure-of-merit (FOM) is improved by 195%. In the mechanical component alone (open-loop system), the product of sensitivity and bandwidth has improved by 151%, with sensitivity increasing by 276%. For closed-loop performance, there is an improvement of 120% for the ratio of open and closed-loop displacements. The product of sensitivity and bandwidth is improved by 27% in the closed-loop system. Excellent immunities to fabrication errors and parameter mismatch are achieved. Experiments show that the displacement of the MEMS accelerometer in the closed-loop system decreased by 86% with 4.85 V feedback voltage compared with that in the open-loop system under a 1 g 100 Hz acceleration input. The static and dynamic nonlinearities in the closed-loop system are improved by 64% and 61%, respectively, compared with those in the open-loop system, in the ±1 g acceleration input range. Besides, the closed-loop system improves the cross-axis sensitivity by 18.43%, compared with that in the open-loop system. It is the first time a closed-loop system for a MEMS accelerometer comprising a mechanical motion preamplifier is successfully implemented experimentally.
本文描述了一种基于遗传算法（GA）的新颖的系统级设计方法，该方法使用自由形式几何形状来设计微机电系统（MEMS）器件。所提出的方法可以同时设计和共同优化包含自由形式几何形状的MEMS器件的电子和机械部件，以实现更好的系统性能，即高灵敏度、良好的系统稳定性和较大的制造公差。此外，自由形式几何形状的引入在设计过程中允许更高的自由度，提高了MEMS器件的多样性以及潜在的性能。提出了一种在闭环控制系统中包含自由形式机械运动前置放大器的MEMS加速度计，以证明该设计方法的有效性。优化过程表明，主要品质因数（FOM）提高了195%。仅在机械部件（开环系统）中，灵敏度和带宽的乘积提高了151%，灵敏度提高了276%。对于闭环性能，开环和闭环位移之比提高了120%。闭环系统中灵敏度和带宽的乘积提高了27%。实现了对制造误差和参数失配的优异耐受性。实验表明，在1 g 100 Hz加速度输入下，与开环系统相比，闭环系统中MEMS加速度计在4.85 V反馈电压下的位移降低了86%。在±1 g加速度输入范围内，与开环系统相比，闭环系统中的静态和动态非线性分别提高了64%和61%。此外，与开环系统相比，闭环系统将交叉轴灵敏度提高了18.43%。这是首次通过实验成功实现了一种包含机械运动前置放大器的MEMS加速度计的闭环系统。
