10 GHz - 30 GHz 高性能压电MEMS谐振式质量传感器研究

基于MEMS 和压电薄膜技术的薄膜体声波谐振（FBAR）微质量传感器因体积小、灵敏度高、分辨率高，受到越来越多的关注。在已有研究的基础上本课题提出研究极高频率（谐振频率大于10GHz, 最高可达30 GHz）FBAR 微质量传感器，以期大幅提升传感器最小可探测质量。随着 FBAR 频率的升高，FBAR谐振器Q值下降、寄生谐振模式增强等问题将影响FBAR质量传感器性能。本项目力图从理论和实验两方面对极高频 FBAR 谐振器展开研究，包括：高质量超薄压电薄膜的成膜工艺研究；二阶谐振模式在极高频FBAR谐振器中的应用；极高频FBAR寄生模式及能量损耗机理分析；声子束缚结构对抑制FBAR寄生模式、提高谐振器Q值的作用。本项目力图将现有的FBAR质量传感器的绝对最小可探测质量降低2到3个数量级。FBAR质量传感器探测精度的提高以及传感器尺寸的进一步减小将大大拓宽其在化学和生物单分子检测中的应用。

FBAR mass sensor based on MEMS and piezoelectric film technologies has received more and more attention, due to its small size, high mass sensitivity and fine mass resolution. The project proposes to study ultra-high-frequency FBAR mass sensor (resonant frequency from 10 GHz to 30 GHz), aimming to improve the minimum detectable mass change of the sensor substantially. With the increase of the frequency, the Q of the resonator is reduced with spurious resonant modes strongly excited, which affects the performance of the FBAR mass sensor. The project seeks to theoretically and experimentally study the ultra-high-frequency FBAR resonator. The research topics: The growth of high quality thin piezoelectric film; Second mode resonance for ultra-high-frequency FBAR resonators; Mechanisms of spurious modes and energy loss; Suppression of spurious modes to increase Q of the FBAR resonators by introducing phonon bound structure。The project aims to lower the minimum detectable mass change of the FBAR mass sensor by 2 to 3 orders of magnitude. The research will greatly broaden the application of FBAR mass sensors in chemical and biological detection of single molecules.