異種圧電材料を集積した革新的超音波ＭＥＭＳデバイスおよび高性能超音波撮像器の創出

于2022财年，进展主要包括三个部分。模拟了双层压电pMUT组合的最佳结构。模拟了用于发射层和接收层的材料。基于模拟结果，我们发现双层pMUT的性能比传统型pMUT高约2.3至2.8倍。考虑到制作的可行性，设计了制作工艺.研究了双压电层异质集成的沉积条件。根据模拟结果，通过选择合适的中间电极，首次实现了单晶AlN在PMN-PT薄膜上的叠层集成。接下来，我们探索了纯钙钛矿相PZT堆叠在AlN薄膜上的沉积条件。因此，异质薄膜堆叠在彼此之上的集成成功3。双层pMUT的制造和表征。制备了AlN/PMN-PT型和PZT/AlN型pMUT。通过在薄膜上施加驱动电压来确认所有压电层的致动。到目前为止，器件的谐振频率和传输性能进行了表征。现在我们正在进行灵敏度测量的实验。

In FY2022, the progress mainly includes 3 parts.1. The best structure for a dual-piezo-layer pMUT combination was simulated. The material used for the transmitting layer and receiving layer was simulated. Based on the simulation result, we found that the performance of dual-layer-pMUT was about 2.3 to 2.8 times higher than the conventional type pMUT. Considering the fabrication feasibility, the fabrication process was designed.2. The deposition condition for hetero-integration of the dual piezoelectric layer was researched. Based on the simulation result, we first realized the integration of single crystal AlN stacked on PMN-PT thin film by selecting suitable intermediate electrodes. Next, we explored the deposition condition for pure-perovskite-phase PZT stacked on AlN thin film. As a result, the integration of heterogeneous thin films stacked on top of each other succeeded3. The dual-layer pMUT was fabricated and characterized. We fabricated AlN/PMN-PT type pMUT and PZT/AlN type pMUT. The actuation of all the piezoelectric layers was confirmed by applying driving voltage on the thin film. Up to now, the resonant frequency and transmitting performance of the devices were characterized. Now we are setting up experiments for sensitivity measuring.