摘要
基于介电润湿的微液滴操控已被众多学者实现,但微液滴接触角在饱和阶段随电压变化的数学关系仍未得到较好解决,为此,基于能量最小化原理对Young-Lippmann方程进行了补充和改进。结合理论计算和数值仿真设计了一种叉齿状驱动电极单元数字微流控芯片,并加工出介电层分别为SiO2及SiO2-Si3N4-SiO2两种结构的芯片。实验结果表明,在接触角饱和阶段,所改进的Young-Lippmann方程能在一定程度上反映微液滴接触角的变化趋势。此外,SiO2-Si3N4-SiO2复合介电层结构中的微液滴操控电压低于SiO2单一介电层中微液滴操控电压。
Although manipulation and control of droplets by applying a moderate voltage has been successfully implemented by many investigators,there are hardly any accurate mathematical equations to describe the relationship between droplet＇s contact angle and external voltage during contact angle saturation stage.For this reason,Young-Lippmann equation was improved based on energy minimum principle in this paper.A digital microfluidics chip with jagged driving electrode unites was designed by employing theoretical calculation and numerical simulation,and the chip with two dielectric lagers of SiO2 and SiO2-Si3N4-SiO2 respecti vely was fabricated.The experimental results showed that the improved Young-Lippmann equation could describe preferably the trends of droplet＇s contact angle at the stage of contact angle saturation.Besides,the required voltages in SiO2-Si3N4-SiO2 composite dielectric layer were less than that in SiO2 dielectric layer.
出处
《压电与声光》
CSCD
北大核心
2013年第4期604-608,共5页
Piezoelectrics & Acoustooptics
基金
国家"八六三"计划基金资助项目(2009AA043703)
