为了用超声波键合的方法实现微流控芯片的封装,采用选择性键合方式在聚甲基丙烯酸甲酯(PMMA)基片的微沟道两侧设计、制作了能量引导微结构,用热压法在同一PMMA基片上一次成形了凸起的能量引导微结构和凹陷的微沟道。用套刻和湿法腐蚀的方法制作了复合一体化硅模具。通过正交实验,确定了优化后的热压工艺参数。实验结果表明,由于同时存在凹、凸微结构,因此优化后的热压成形温度比传统的热压凹陷结构的成形温度提高15~20℃,在温度为140℃、保压时间为300S、压力为1.65MPa的实验条件下,微结构的复制精度达到了99%。
In order to use a micro ultrasonic bonding method to package polymer microfluidic auxiliary microstructure named micro energy director is designed and fabricated on two sides chips, an of the microchannel by a selective bonding method in this paper. A hot embossing method is adopted to fabri cate this newly designed Polymethyl Methacrylate(PMMA) substrate containing both convex micro energy directors and concave microchannels,then a complex silicon mold is designed and fabricated by the multi-photolithography and wet etching. By the Taguchi method, the optimized parameters for hot embossing are obtained. Experimental results show that the optimized embossing temperature is 15-- 20 ℃ higher than that of the simply replicate concave microstructure, since concave and convex micro structures are formed simultaneously. With the optimized parameters in an embossing temperature of 140 ℃, holding time of 300 s, and an embossing pressure of 1.65 MPa, the accuracy of replication can be up to 99%.