针对毒品探测的需求, 对高灵敏度、高选择性及可工作于液相环境中的传感器进行了研究, 利用分子印迹技术(MIT), 结合薄膜体声波谐振器(FBAR)和微流体(micro fluidics)技术构造了新型传感器。首先, 阐述了用分子印迹技术制作FBAR吸附层材料的原理, 利用分子印迹技术制备了对特定毒品分子具有专一吸附性的印迹材料, 将其作为吸附层涂覆在基于微机电系统(MEMS)及微流体技术的FBAR上。根据压电方程和运动学方程推导出了FBAR压电振子的等效电路及电学端口输入阻抗公式, 构建了以AlN为压电材料的微流体结构FBAR毒品检测传感器模型。对该结构的FBAR传感器进行了理论研究和公式推导, 并在理论模型的基础上进行了仿真实验, 得到了单位面积质量响度达0.8 pg/Hz·cm2的FBAR传感器。得到的实验结果远高于石英晶体微天平这一传统的质量敏感型传感器, 可实现对溶液中毒品分子的快速检测。

A highly sensitive and high selective sensor which can detect drug molecules in a liquid environment was explored. By combining the Molecular Imprinting Technique (MIT), Film Bulk Acoustic Resonator (FBAR) and the micro fluidic technology, the new sensor was constructed. The preparing principle of adsorption layer materials for FBAR by the MIT was introduced and the Imprinting material with special adsorption properties for the special drug was developed by the MIT. Then, the material was coated on a FBAR as a adsorption layer based on a Micro-electrical-mechanical System and the micro fluidic technology. According to the piezoelectric equation and dynamic equation, the input impedance formulas of the equivalent circuit and electric port for the FBAR piezoelectric vibrator were derived. Furthermore, a model of the micro fluidic system with the MIT plus FBAR-based drug detection sensor was designed and a detailed theoretical derivation and analysis was performed. Finally, the sensor model was simulated using practical operating parameters. The results show that the quality of the mass loudness per unit area of the sensor is up to 0.8 pg/Hz·cm2, which is much higher than the quality of a conventional Quartz Crystal Microbalance (QCM) sensor. This advantage can greatly enhance the performance of the sensor for drug detection in the liquid environment.