An increasing demand for surface acoustic wave filters with high performances contributes to the necessity of reducing sizes and costs. The present work proposes a multilayered structure of high-velocity layer/SiO2/interdigital transducers (IDTs)/piezoelectric-single-crystal substrate to further validate the strengths of packageless devices. Resonators based on the SiNx/SiO2/IDTs(Cu)/15°Y-X LiNbO3 structure are simulated and analyzed. One-port resonators are designed, fabricated and tested on the basis of the simulation, and results validates the feasibility of no encapsulation. Finally, by using this multilayered structure, a packageless filter with a center frequency of 2.14 GHz and an ultra-small size of 0.695×0.490×0.122 mm3 is successfully designed and realized, maintaining well-balanced performances. This work has demonstrated the strengths of packageless devices which can be obtained by utilizing the proposed multilayered structure, and may promote the development of device miniaturization. [2021-0035]

中文翻译：

---

超小尺寸无封装声波器件的多层结构


对高性能表面声波滤波器日益增长的需求导致了减小尺寸和成本的必要性。目前的工作提出了高速层/SiO2/叉指换能器（IDT）/压电单晶基板的多层结构，以进一步验证无封装器件的优势。对基于SiNx/SiO2/IDTs(Cu)/15°YX LiNbO3结构的谐振器进行了仿真和分析。在仿真的基础上设计、制作并测试了单端口谐振器，结果验证了无封装的可行性。最终，利用这种多层结构，成功设计并实现了中心频率为2.14 GHz、超小尺寸0.695×0.490×0.122 mm3的无封装滤波器，并保持了良好的性能平衡。这项工作证明了利用所提出的多层结构可以获得的无封装器件的优势，并可能促进器件小型化的发展。 [2021-0035]