基于典型MEMS膜/梁结构的RF MEMS柔性器件弯曲特性模型理论与实验研究

RF MEMS flexible devices have an extremely wide application prospect in airborne/spaceborne radars and IoT (internet of things) communication systems due to their unique flexibility and ductility, as well as the efficient and low cost fabrication process. However, because of the lack of modeling of bending characteristics and experimental characterizations of RF MEMS flexible devices, the application researches of such devices have been severely restricted. Therefore, this project proposes the bending characteristics model of RF MEMS flexible devices according to complex environment applications. A structure deformation/stress coupling model based on device/substrate dual deformation has been firstly established. And then, the mechanical/microwave properties analytical model based on the coupling model has been built. Finally, the complete bending characteristics model and design method of RF MEMS flexible devices have been established. The model realizes the good grasp of the performance variation regularity of RF MEMS flexible devices under the bending substrate condition. The RF MEMS flexible devices prototypes based on typical MEMS membrane/beam structure have been developed. These prototypes can validate the effectiveness of the bending characteristics model and design method. The project will provide profound theoretical foundation for the realization of the deep researches and practical applications of RF MEMS flexible devices.

RF MEMS柔性器件以其独特的可弯曲延展性及其高效、低成本的制造工艺，在机载/星载雷达和物联网通信系统中具有非常广阔的应用前景。然而，由于目前缺乏对RF MEMS柔性器件弯曲特性的理论建模和实验表征，因此严重制约着RF MEMS柔性器件的应用研究。为此，本项目根据适用于复杂环境应用的RF MEMS柔性器件弯曲特性模型这一总体目标，首次提出一种基于器件/基板双变形的结构形变/应力耦合关系模型以及基于这一耦合模型的器件力学/微波性能影响解析模型，建立完整的分析RF MEMS柔性器件弯曲特性的模型理论和方法，实现弯曲变形条件下RF MEMS柔性器件性能参数变化规律的掌握，研制出基于典型MEMS膜/梁结构的RF MEMS柔性器件样片，验证所建立的弯曲特性模型理论和方法的正确性和有效性，从而为真正实现RF MEMS柔性器件的深入研究和实际应用提供坚实的理论基础。

针对项目的研究内容与目标，首次提出并建立了完整的分析RF MEMS柔性器件弯曲特性的多物理域模型理论和设计方法，包括典型MEMS双端固支梁、悬臂梁、V型梁和电容结构的力学弯曲特性、动态弯曲特性和微波弯曲特性模型以及阻抗预匹配模型。通过理论分析、优化设计和工艺制备研制出了基于典型MEMS膜/梁结构的RF MEMS柔性器件样片，测试结果与理论计算结果和仿真结果对比显示变化规律完全一致，且最大误差不超过±10%，验证了所建立的弯曲特性模型和设计方法的正确性和有效性，为真正实现RF MEMS柔性器件的深入研究和实际应用提供了坚实的理论基础。本项目的科学意义在于通过对构成各类RF MEMS柔性器件的基本膜/梁结构进行全面而深入的建模研究，构建出最底层的典型MEMS膜/梁结构力学、动态、热学、微波等多物理域弯曲特性模型。四种典型MEMS膜/梁结构多物理域弯曲特性模型具有普适性，可以作为最基本的“拼图”构造出更为复杂的RF MEMS柔性器件多物理域弯曲特性模型，从而为绝大多数的RF MEMS柔性器件结构设计提供坚实的理论基础。本项目的研究成果可以应用于机载/星载雷达、智能蒙皮、可穿戴设备等细分领域中，解决其射频微系统面临的复杂环境空间下共形、小型化、轻量化内在需求，实现RF MEMS柔性器件及系统弯曲条件下的性能预测和优化补偿，极大推进RF MEMS柔性器件及系统的实用化进程。