键合是微流控芯片制作的关键技术之一.目前广泛应用的PDMS微流控芯片一般通过高真空(压力低于10 Pa)氧等离子体活化及键合进行制备,需要昂贵的分子泵等设备.通过工艺改进,使用装配普通油泵的等离子体去胶机,在中真空(27 Pa)成功进行聚二甲基硅氧烷(PDMS)表面改性及键合.处理后的PDMS表面亲水性得到极大改善,贴合后可永久性密封,制作微流控芯片.使用扫描电镜,红外光谱及接触角测量仪进行了表征.与文献报道的高真空氧等离子体处理方法相比,效果基本一致,却大幅度降低了对设备系统的要求,并缩短了操作时间.Bonding is one of key processes for fabrication of microfluidic chip.Normally poly(dimethylsiloxane)(PDMS) replica,the most popular microfluidic chip material,were bonded after activated by oxygen plasma in high vacuum(pressure lower than 10 Pa),which need expensive pumps.Here a method was developed for modifying and bonding PDMS replicas in middle vacuum(pressure higher than 13.3 Pa) by oxygen plasma.After treated by oxygen plasma 2~70 s in a system equipped with a normal oil pump(background vacuum 27 Pa),the PDMS replicas were irreversibly sealed when the treated surfaces were brought into touch.Operation parameters,irritation voltage and treatment time,were optimized.And the hydrophilic behavior of PDMS was improved greatly after activating and then decreased slowly to hydrophobic as same as before treatment,but could be kept for a long time by immersed into water immediately after bonding.Compared with the reported procedures using oxygen plasma pretreatment under high vacuum,the presented approach needs simpler and cheaper equipment,and has a higher efficiency.And the bonded chip has same intensity and surface properties,which was proved by FTIR,TEM and contact angle measurement.Other polymer microfluidic replica,e.g.,PMMA,PET,PC etc could be activated and sealed by this method too.福建省科技重点项目(2003H86)资
