Abdelaal Yara, Liffredo Marco, Villanueva Luis Guillermo
Advanced NEMS Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Route Cantonale, 1015 Lausanne, Switzerland.
Sensors (Basel). 2025 Aug 31;25(17):5370. doi: 10.3390/s25175370.
Suspended microchannel resonators (SMRs) are powerful tools for mass, density, and viscosity sensing. Among various transduction methods, full piezoelectric transduction offers key advantages, including on-chip integration, low energy dissipation, and linear response. This work explores sub-200 nm AlScN thin films for SMR transduction, benchmarking them against their well-established AlN predecessor. By integrating the piezoelectric stack into low-stress silicon nitride (ls-SiN) beam resonators, we investigate the impact of bottom electrode design, photoresist removal prior to deposition, and deposition bias on film quality. Characterization includes X-ray diffraction (XRD), scanning electron microscopy (SEM), d piezoelectric coefficient, relative dielectric permittivity, and breakdown field measurements. Results illustrate the impacts of the studied parameters and demonstrate a fourfold increase in d, compared to AlN, confirming the strong potential of AlScN for high-performance SMR transduction.
悬浮微通道谐振器（SMR）是用于质量、密度和粘度传感的强大工具。在各种传感转换方法中，全压电传感转换具有关键优势，包括片上集成、低能量耗散和线性响应。本研究探索用于SMR传感转换的亚200nm厚的AlScN薄膜，并将其与已成熟的AlN薄膜进行对比。通过将压电堆栈集成到低应力氮化硅（ls-SiN）梁式谐振器中，我们研究了底部电极设计、沉积前光刻胶去除以及沉积偏压对薄膜质量的影响。表征方法包括X射线衍射（XRD）、扫描电子显微镜（SEM）、d压电系数、相对介电常数和击穿场测量。结果说明了所研究参数的影响，并证明与AlN相比，d增加了四倍，证实了AlScN在高性能SMR传感转换方面的巨大潜力。
