声表面驻波局部图案化微操控方法  

Localized particle patterning via standing surface acoustic wave micromanipulation

作　　者：张宇翔 刘久玲[1] 刘明华[1] 游然 何世堂[1] ZHANG Yuxiang;LIU Jiuling;LIU Minghua;YOU Ran;HE Shitang(Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190;University of Chinese Academy of Sciences,Beijing 100049)

机构地区：[1]中国科学院声学研究所,北京100190 [2]中国科学院大学,北京100049

出　　处：《声学学报》2024年第3期464-471,共8页Acta Acustica

基　　金：国家自然科学基金项目(12074404)资助。

摘　　要：针对目前声表面驻波微操控方法在微流道的完整宽度上形成驻波图案,缺乏实现区域化操控的可行性的问题,量化分析了短脉冲激发的声表面波在声学微操控结构中产生与控制局部微粒图案的方法。通过对单指对叉指换能器机械波形的加式合成,建立了短脉冲激励下的波形传播解析模型,结合有限元方法建立立式声表面波微操控器件的全截面仿真模型,研究对激励信号施加脉冲延迟和频率调制时,微操控器件的时均基底位移以及微流道内声场分布的变化规律。为验证理论模型,制作微操控器件进行实验测试。结果表明,通过修改激励信号的相对时延和有效脉冲时间,可以有效地控制声场中生成驻波区域的位置及宽度,二者均呈线性正相关,与理论及仿真结果相符。The current method of micromanipulation using standing surface acoustic waves generates standing wave patterns across the full width of the microfluidic channel and lacks the ability to perform localized manipulations.This paper analyzes and quantifies techniques for generating and controlling localized particle patterns in acoustic micromanipulation structures using surface acoustic waves of short-pulse excitation.An analytical computational model is developed to study waveform propagation under short-pulse excitation,considering the contribution of each finger pair in the forked-finger transducer.Additionally,a full-section simulation model of the vertical surface acoustic wave micromanipulator is combined with the finite element method to study the time-averaged base displacement of the micromanipulator and changes in the acoustic field distribution when pulse delay and frequency modulation are applied to the excitation signal.To validate the theoretical model,the micromanipulator device is fabricated and experimentally tested.The results demonstrate that modifying the relative time delay and an effective pulse time of the excitation signal enables effective control of the position and width of the generated standing wave region in the acoustic field,with a positive linear correlation between the two parameters and consistency with both theoretical and simulation results.

关 键 词：声表面驻波 微操控 调制短脉冲 微粒图案化 

分 类 号：TB5[理学—物理]