中文摘要：

报道了在微流系统中使用基于叉指聚焦换能器的声表面波的一种有效方法。利用lift-off和软光刻技术在铌酸锂（LiN-bO3）压电单晶片基底上制作器件。使用有限元分析软件COMSOL Multiphysics分别模拟聚焦叉指电极和平行叉指电极两种声表面波的形成和分布。通过与相同条件下的平行叉指电极比较,说明聚焦叉指电极可以显著增强声表面波的能量。实验结果说明聚焦叉指电极可以在几秒内快速的混合PS（聚苯-乙烯）球。这种器件为生物应用提供了一种有用的微流芯片体系。

英文摘要：

This work reported an effective approach using surface acoustic waves based on focused interdigital transducers（IDTs）in microfluidic systems.The device was fabricated using lift-off and soft lithography technologies on the piezoelectric LiNbO3 single-crystal substrate.Finite element analysis software（COMSOL Multiphysics）was employed to simulate the generation and distribution of the surface acoustic waves for focused and parallel IDTs,respectively.It demonstrated that the intensity of surface acoustic waves was dramatically enhanced by the focused IDTs,comparing with the parallel IDTs under the same conditions.The experiment results showed that the focused IDTs can mix polystyrene microparticles rapidly with several seconds.The device provides an affordable lab-on-chip system for biological applications.