In this study, we present the design, the modeling, the fabrication, and the characterization of ring–dot type piezoelectric thin-film transformers (PTFTs). The structure of the PTFTs was a simple circular plate of Pb(Zr,Ti)O3 (PZT) thin film on a Si layer with ring–dot top electrodes and it was suspended by four pantograph-shaped bridges. We estimated the performance of the PTFTs by finite-element method simulations. In accordance with the FEM simulation model, PZT thin films were deposited on silicon-on-insulator substrates and microfabricated into PTFTs with ring–dot structures. From the produced devices, an admittance circle measurement was carried out, enabling us to predict performance. The actual output characteristics of the PTFTs were clearly observed at a resonance frequency (f r) of 4.57 MHz. At this point, a voltage gain of 0.22 and a power density of 704 W cm−3 were measured, under a load resistance (R L) of 22 Ω.

中文翻译：

---

具有环点结构的压电PZT薄膜变压器

在这项研究中，我们介绍了环点型压电薄膜变压器 (PTFT) 的设计、建模、制造和表征。PTFT 的结构是一个简单的圆形 Pb(Zr,Ti)O3 (PZT) 薄膜圆板，位于带有环点顶部电极的 Si 层上，并由四个受电弓形桥悬挂。我们通过有限元方法模拟估计了 PTFT 的性能。根据有限元模拟模型，将 PZT 薄膜沉积在绝缘体上硅衬底上并微制造成具有环点结构的 PTFT。对生产的设备进行导纳圆测量，使我们能够预测性能。在 4.57 MHz 的谐振频率 (fr) 下可以清楚地观察到 PTFT 的实际输出特性。此时，电压增益为 0。