Zhang Yi, Zhou Jie, Xie Ying, Tang Chuying, Zou Yang, Tovstopyat Alexander, Yu Hongyu, Sun Chengliang
IEEE Trans Ultrason Ferroelectr Freq Control. 2020 Sep;67(9):1916-1921. doi: 10.1109/TUFFC.2020.2985983. Epub 2020 Apr 6.
This article reports on a design journey for ScAl - N-based dual-mode hybrid quasi-surface and bulk acoustic wave (quasi-SAW/BAW) resonators. Four types of acoustic excitation configurations are proposed in these designs based on Sc AlN/6H-SiC stack architectures. The influence of Sc AlN materials, film thickness, and device configurations on the performance is investigated. After design optimization, the final dual-mode hybrid quasi-SAW/BAW resonators comprise of top electrode, partially etched Sc AlN pillars, and bottom electrode, which are stacked on a 6H-SiC substrate. The coupled quasi-SAW and BAW excited in the hybrid resonators enhance the resonance for both quasi-Rayleigh and quasi-Sezawa modes which results in a high effective coupling coefficient (K) and phase velocity ( v ). Simulation results show that the optimized hybrid quasi-SAW/BAW resonator based on Mo/Sc AlN/Mo/6H-SiC configuration with SiO filling the grooves has a remarkable K value of 14.55% and a high v above 7500 m/s, which make this kind of dual-mode hybrid quasi-SAW/BAW resonators have great potential in wideband and high-frequency applications.
本文报道了基于ScAlN的双模混合准表面和体声波（准SAW/BAW）谐振器的设计历程。在这些设计中，基于ScAlN/6H-SiC堆叠结构提出了四种声学激励配置。研究了ScAlN材料、薄膜厚度和器件配置对性能的影响。经过设计优化，最终的双模混合准SAW/BAW谐振器由顶部电极、部分蚀刻的ScAlN柱和底部电极组成，它们堆叠在6H-SiC衬底上。混合谐振器中激发的耦合准SAW和BAW增强了准瑞利模和准濑泽模的共振，从而产生了高的有效耦合系数（K）和相速度（v）。仿真结果表明，基于Mo/ScAlN/Mo/6H-SiC配置且SiO填充凹槽的优化混合准SAW/BAW谐振器具有14.55%的显著K值和高于7500 m/s的高v值，这使得这种双模混合准SAW/BAW谐振器在宽带和高频应用中具有巨大潜力。
