基于压电电子学效应的可调谐FBAR工作机理研究及其应用

薄膜体声波谐振器（FBAR）是一种性能优异的新型谐振器，现已广泛应用于各种电子设备中。为了解决当前FBAR高度集成化造成的负面影响，可调谐FBAR的概念被提出，但现有的调谐技术尚存不足，仍需进一步研究进行改善。本项目拟将压电电子学的机械调控理念拓展应用于FBAR中，利用ZnO或AlN薄膜的压电半导体双向耦合效应，在传统FBAR的电学拓扑结构中引入机械调控电容，从而实现对FBAR的机械调谐。主要研究内容为：基于压电半导体宏观唯象理论，利用半解析有限元法、模态叠加法，系统地研究压电半导体高频声波器件的物理机制、工作机理；在此基础上采用小扰动假设、非线性离散的方法优化求解效率，开发便捷化的理论分析工具；进一步探讨新型机械调谐型FBAR作为传感器应用的可行性，推导频率与待测量之间的解析公式。本项研究的顺利进行将有利于拓展压电电子学的研究范围，为新型可调谐FBAR的设计提供理论支撑。

Film Bulk Acoustic Wave Resonator (FBAR) is a new type of resonator with outstanding working performance, which has been widely applied in nearly every electronic product. In order to resolve the difficulty arising from the highly integrated device, the idea for the design of tunable FBAR was proposed. However, the existing tunable approaches are kind of deficient for real application, and further researches are still necessary to improve the performance of tunable FBAR. In this project, the concept of mechanical-control in Piezotronics is expanded into the design of FBAR. The two-way coupling effect of piezoelectric and semiconductor property in ZnO or AlN film is utilized, and a mechanical controlling capacitance is introduced into the traditional topological structure of electric, which finally gives us a mechanical tunable FBAR. The main contents of the present project are: Systematically study the physical mechanism and working principle of piezoelectric semiconductor acoustic wave resonator with the phenomenological theory of piezoelectric semiconductor, and also the semi-analytical finite element method, the mode superposition method. Based on the researching achievements, develop efficient theoretical tool with the assumption small perturbation and the method of nonlinear discretization. Furthermore, discuss the possibility of the application of the new designed mechanical tunable FBAR in sensing field, and derive the analytical equation for the relation of frequency and detectable variable. The successful implementation of this project will be helpful for expanding the research scope of Piezotronics, and provide theoretical foundation for the design of new type of tunable FBAR.