2022 Fiscal Year Annual Research Report
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
| Project/Area Number |
22J10831
|
|---|
| Allocation Type | Single-year Grants |
|---|
| Research Institution | Tohoku University |
|---|
Principal Investigator |
QI XUANMENG 東北大学, 工学研究科, 特別研究員(DC2)
|
|---|
| Project Period (FY) |
2022-04-22 – 2024-03-31
|
| Keywords | Piezoelectric thin film / Dual-layer pMUT / Hetero-integration / Stacked piezo-layer |
|---|
| Outline of Annual Research Achievements |
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 succeeded
3. 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.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
Up to now, we have already fabricated and prototyped the dual-layer pMUT with heterogenerous piezoelectric thin film stacked on the top of each other. We have already started and finished part of the evaluation. The transmitting performance, e.g. the dependence of displacement on resonant frequency, transmitting sound pressure, has been measured. Now we are measuring the sensitivity properities, such as the relationship between sound pressure and sensing voltage, which is progressed as the plan. Currently, the degign for the future pMUT array is under progress and the the pMUT array would be fabricated in the following several monthes. In consideration of the above situation, I think this research is progressing as expected.
|
| Strategy for Future Research Activity |
1. Design and fabricated the dual-piezo-layer pMUT array.
2. Characterize the transmitting and the receiving performance of the pMUT array.
3. Try to obtain the ultrasonic image by using this dual-layer pMUT array, and research other potential applications.
|
