基于锁相环接口电路的高性能扭转谐振模态微悬臂梁传感器研究

扭转谐振模态微悬臂梁低能耗、高品质因数的特性,使它比传统的弯曲模态悬臂梁拥有更高的灵敏度和分辨率.将微传感器加工技术和生物检测技术相结合,利用扭转谐振模态微悬臂梁传感器对生物素和亲和素的特异性反应进行检测,结果传感器的灵敏度为0.9 pg/Hz,分辨可达到49 fg.本文还着重介绍了为谐振梁传感器设计的以锁相环(Phase-Locked Loop简称PLL)为核心的闭环接口电路,分析了悬臂梁和电路在闭环系统中的工作特性,并探讨了解决谐振式传感器在使用中常见的稳定性差、噪声干扰强等问题的方法.

High Performance Torsional Resonant Microcantilever Beam Based On Phase-Locked Loop Interface Circuit

Due to its advantages such as low energy consumption and high quality factor , microcantilever beam of torsional resonance mode demonstrate markedly higher sensitivity and resolution compared with conventional microcantilever beam of bending resonance mode. Combining micro-machining and bio-detecting technique, the measurements, via detecting the specific reaction with avidin and biotin by the resonator, and the sensitivity and resolution of the sensors is 0.9pg/Hz and 49fg respectively. Additionally, focused on Phase-Locked Loop, this letter emphatically introduced closed-loop interface circuits designed for the resonator and analyzed the loading characteristics of as-prepared sensors and circuits functionalized as a closed-loop system. Finally, aiming at the familiar problems such as poor stability and strong noise-interference, a few methods were investigated.