3D打印微流控芯片与FPC的高可靠软硬异质集成及界面调控研究

Research on High-Reliability Rigid-Flexible Heterogeneous Integration and Interface Regulation of 3D-Printed Microfluidic Chips with FPC

摘要: 微全分析系统的集成化发展，对3D打印微流控芯片与柔性电路板(FPC)的异质集成提出更高要求，但二者集成存在界面粘附性差、胶液易毛细堵塞流道的问题，严重影响器件性能。针对此，本文提出界面复合改性与溶剂辅助边缘清除的复合封装工艺，构建软硬异质集成架构。采用无水乙醇超声25 min联合氧等离子体处理3 min改性FPC聚酰亚胺表面，提升界面润湿性与机械互锁能力；通过溶剂辅助技术在流道边缘构建1 mm“无胶缓冲区”，杜绝胶液堵塞。实验表明，该工艺实现芯片共形密封，器件稳定运行寿命从不足24 h延长至7天以上，电极导通性能稳定，为微流控系统高可靠软硬异质集成提供了有效技术方案。

Abstract: The integrated development of micro total analysis systems (μTAS) has put forward higher requirements for the heterogeneous integration of 3D-printed microfluidic chips and flexible printed circuits (FPC). However, the poor interfacial adhesion and the easy capillary blockage of microchannels by adhesive during the integration seriously impair the device performance. To address these issues, this paper proposes a composite packaging process combining interfacial composite modification and solvent-assisted edge cleaning, and constructs a rigid-flexible heterogeneous integration architecture. The polyimide surface of FPC was modified by ultrasonic treatment with anhydrous ethanol for 25 minutes combined with oxygen plasma treatment for 3 minutes to improve the interfacial wettability and mechanical interlocking capability. A 1 mm “adhesive-free buffer zone” was constructed at the edge of microchannels via solvent-assisted technology to completely eliminate adhesive blockage. Experimental results show that this process achieves conformal sealing of the chip, extending the stable operation lifetime of the device from less than 24 hours to more than 7 days with stable electrode conduction performance. This study provides an effective technical solution for the high-reliability rigid-flexible heterogeneous integration of microfluidic systems.