This paper discusses the applicability of free side edges to a thickness shear bulk acoustic resonators (TSBARs) on a rotated Y-cut lithium niobate plate for suppression of lateral energy leakage and the transverse mode resonances. It is shown both theoretically and experimentally that free edges are effective to suppress lateral leakage and transverse mode resonances in free-standing TSBARs. Although this technique is applicable only to the X side boundaries, it is shown that the Y′ side perpendicular to the X side can be designed for the piston mode operation independently by the simple two-dimensional analysis ignoring wave propagation toward the X direction. Then the discussion is extended to the solidly-mounted TSBAR. It is shown that this technique works well also for this case, and removal of the first few Bragg layers is enough for the transverse mode suppression.

本文讨论了自由侧边对旋转Y切割铌酸锂板上的厚度剪切体声波谐振器 (TSBAR) 的适用性，以抑制横向能量泄漏和横向模式谐振。理论和实验都表明，自由边缘可有效抑制独立 TSBAR 中的横向泄漏和横向模式共振。虽然该技术仅适用于X侧边界，但表明通过简单的二维分析，可以独立地为活塞模式操作设计垂直于X侧的Y'侧，忽略波向X 的传播方向。然后讨论扩展到牢固安装的 TSBAR。结果表明，这种技术也适用于这种情况，去除前几个布拉格层足以抑制横模。