斜交指叉式表面聲波元件在微液珠控制之應用

Application of Slanted Finger Interdigital Transducer to Control Micro Droplets

張益祥(I-Hsiang Chang)

指導教授 ： 吳政忠

國立臺灣大學/工學院/應用力學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.10393

摘要

無資料

關鍵字

表面聲波 ； 多通道微流體晶片 ； 耦合模型理論 ； 相對振幅分佈 ； 斜交指叉式表面聲波元件 ； C18疏水性薄膜 ； 聲射流 ； 接觸角

並列摘要

Using Surface acoustic wave (SAW) to drive droplets is developed recently. SAW could induce an acoustic streaming inside a droplet and move it along the propagation direction. However, the SAW amplitudes radiated from uniform IDT are equivalent along the aperture, and they move the droplets within the same delay line simultaneously. This phenomenon is not suitable for a multi-channel microfluidic chip. For this reason, SFIT is used to replace uniform IDT. The SAW amplitude profile excited by SFIT is not uniform along the aperture, and the position of the maximum amplitude can be changed by adjusting the input frequency. Therefore, the droplets can be driven individually by varying the frequency. In addition, the frequency response can be used to detect the position of the droplet because the transmitted SAW intensity is radiated into the liquid.
In this thesis, because hydrophobic film and acoustic streaming dominate the performance of driving droplets, we introduce these mechanisms first. And then, we use the coupling-of-modes (COM) model to simulate the amplitude profile and the frequency response of SFIT. According to the simulation, we can design optimum SFIT to detect and move the droplets. The frequency responses of the experiments for detecting droplets show a good agreement with the simulated results. Furthermore, the droplets are also driven respectively at different frequency by SFIT. Therefore, using SFITs to construct a multi-channel microfluidic chip is proven feasible.

並列關鍵字

COM model ； OTS ； Multi-channel microfluidic chip ； Amplitude profile ； Contact angle ； SAW ； SFIT ； Acoustic streaming

參考文獻

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