PC微流控芯片黏接筋与溶剂的协同辅助键合

为了在微流控芯片上形成封闭的微通道等功能单元,克服热压键合中微流控结构的塌陷和热压所致芯片微翘曲对后续键合的影响,提出了一种适用于硬质聚合物微流控芯片的黏接筋与溶剂协同辅助的键合方法。以聚碳酸酯(PC)微流控芯片为研究对象,通过热压法在PC微流控芯片上的微通道两侧制作凸起的黏接筋,通过化学溶剂丙酮微溶PC圆片的表面,然后将PC圆片与带有黏接筋的PC微流控芯片贴合、加压、加热,从而实现微流控芯片的键合。分析了键合机理,并对键合工艺参数进行了优化。实验结果表明:键合质量受丙酮溶剂溶解PC圆片的时间和键合温度的影响,能够保证键合质量的最佳键合温度为80~90°,溶解时间为35~45s,芯片的键合总耗时为3min。与已有键合工艺相比,所提出的黏接筋与溶剂辅助键合工艺有效提高了键合效率。该键合方法不仅适用于具有不同宽度尺寸微通道的微流控芯片,还可扩展用于不同材料的硬质聚合物微流控芯片。

Synergistic bonding process of solvent and tendon for PC-based microfluidic chips

To form enclosed microchannels in microfluidic chips, a bonding method suitable for a polymer microfluidic chip was proposed to overcome the microstructure collapse of hot bonding and the microwarp of microfluidic chip fabricated by hot embossing and to ensure the subsequent bonding. A PC microfluidic chip was used in the research. The heating pressure method was used to prepare bonding tendons in two sides on microchannels of the microfluidic chip and the chemical solvent acetone was used to dissolve the surface of PC wafer slightly. Then the PC wafer and the microfluidic chip with bonding tendons were fitted, pressured and heated, and the bonding process was implemented. The bonding mechanism was analyzed and the bonding process parameters were also optimized. Experimental results illustrate that dissolving time and bonding temperature influence the bonding quality obviously. The microfluidic chip with acceptable quality is achieved when the bonding temperature is between 80° and 90℃ and the dissolving time is between 35 s and 45 s. Entire bonding process just needs 3 minutes. As compared with traditional process, this bonding process has improved the processing efficiency greatly and it not only can be used for the microfluidic chip with different channel widths, but also is suitable for the microfluidic chips fabricated by other polymers.