变温蠕变实验的COP微流控芯片热压制备

Variable temperature quasi-creep experiment for fabrication of microfluidic chip using Cyclo-olefin Polymer(COP)

采用热压方法制备了COP微流控芯片。由于温度对微结构热压成形的质量影响最大,基于材料的粘弹性特性,通过变温准蠕变实验获得热压参考温度Tr,即从材料玻璃点温度以下开始,以1.5℃/min的温升速率,在热压工作压力下热压聚合物基片,通过温度-位移实时采集系统获得材料的温度-形变曲线,曲线的拐点对应的温度即是热压参考温度。实验证明了在该温度下热压成形具有高复制精度和低整体变形,微结构宽度和深度方向的复制精度分别达到97.6%和94.3%。电泳实验和DNA分析实验得出COP芯片具有良好的生物兼容性,适用于生化分析。

A hot embossing method is used to fabricate Cyclo-olefin Polymer (COP) microfluidic chip in this paper. Since temperature is the most important parameter in hot embossing process, the variable temperature quasi-creep experiment is set up to study the viscoelastic character of COP for determination of the working temperature. From a point of temperature below COP's (Tg) temperature, applying the embossing working pressure, the temperature-deformation curve at slow temperature rising speed (1.5°C/min) is obtained. According to this curve, the hot embossing of microstructure under embossing reference temperature (Tr) has a high accuracy and low substrate deformation. Experiments show that average duplication precision is 97.6% in width and 94.3% in depth. Electrophoresis and DNA separation experiments have been done on fabricated COP chip, which shows that COP chip has excellent biologic compatibility and is suitable for biochemical analysis.