Institute of Microelectronics, Tsinghua University, Beijing 100084, China.
Sensors (Basel). 2013 Jul 26;13(8):9624-34. doi: 10.3390/s130809624.
A 1 MHz piezoelectric micromachined ultrasonic transducer (pMUT) array with ultra-high element density and low crosstalk is proposed for the first time. This novel pMUT array is based on a nano-layer spin-coating lead zirconium titanium film technique and can be fabricated with high element density using a relatively simple process. Accordingly, key fabrication processes such as thick piezoelectric film deposition, low-stress Si-SOI bonding and bulk silicon removal have been successfully developed. The novel fine-pitch 6 × 6 pMUT arrays can all work at the desired frequency (1 MHz) with good uniformity, high performance and potential IC integration compatibility. The minimum interspace is ~20 μm, the smallest that has ever been achieved to the best of our knowledge. These arrays can be potentially used to steer ultrasound beams and implement high quality 3-D medical imaging applications.
首次提出了一种具有超高单元密度和低串扰的1MHz 压电微机械超声换能器（pMUT）阵列。这种新型 pMUT 阵列基于纳米层旋涂锆钛酸铅薄膜技术，可使用相对简单的工艺实现高单元密度。因此，已经成功开发了关键制造工艺，如厚压电薄膜沉积、低应力 Si-SOI 键合和体硅去除。新型细间距 6×6 pMUT 阵列都可以在期望的频率（1MHz）下工作，具有良好的均匀性、高性能和潜在的 IC 集成兼容性。最小间隔为~20μm，据我们所知，这是迄今为止达到的最小间隔。这些阵列可用于引导超声波束并实现高质量的 3D 医学成像应用。
