基于声表面波驱动器的液体单方向驱动

• 作 者: 黄远 李以贵 颜平 王欢 李俊衡 杉山进
• 机 构: 上海应用技术大学理学院,日本立命馆大学微系统系,
• 出 处: 微纳电子技术
• 发表日期: 2017年01期
• 关键词: floating electrode type unidirectional transducer (FEUDT) unidirectional surface

设计了一种浮动电极型单向换能器(FEUDT)结构,用于激发单向声表面波(SAW),从而实现液体的单向驱动。通过对FEUDT结构模型的阻抗分析与SAW传播分析,获得了SAW驱动器的谐振频率、最佳驱动频率和最优指条宽度。利用剥离工艺,在128°旋转Y切向X方向传播的铌酸锂基板上,制作了周期为80μm、指条对数为40对、指条金属层厚度为1μm、指条宽度为7.3μm的FEUDT型SAW驱动器。搭建了SAW驱动器的驱动系统,实现了液体在器件表面上单向驱动。实验结果表明:FEUDT型SAW驱动器在驱动功率为4 W、驱动频率为48.8 MHz的电信号激励下,液滴在SAW驱动器表面上的驱动速度可达50 mm/s;在驱动功率为6.2 W、驱动频率为48.8 MHz的电信号激励下,液体在微流道中的驱动速度约为20 mm/s。

A floating electrode unidirectional transducer (FEUDT) structure was designed to excite one-way SAW to achieve unidirectional driving of the liquid. Through the impedance analysis and SAW propagation analysis of FEUDT structural model, the resonant frequency, optimum driving frequency and optimal finger width of SAW driver are obtained. Using a lift-off process, a lithium niobate substrate having a cycle of 80 μm, a finger number of 40 pairs, a finger metal layer thickness of 1 μm and a finger width of 7.3 μm FEUDT type SAW driver. The drive system of SAW driver was built, which realized the unidirectional driving of liquid on the device surface. The experimental results show that the FEUDT SAW driver can drive 50μm / s on the surface of SAW driver under the excitation of 4W drive power and 48.8MHz drive frequency. When the drive power is 6.2W, Excited by an electrical signal with a 48.8 MHz drive frequency, the drive speed of the liquid in the microchannels is about 20 mm / s.