Institute of Microelectronics, NCSR Demokritos, PO BOX 60228, 153 10 Aghia Paraskevi, Greece.
Lab Chip. 2010 Feb 21;10(4):462-9. doi: 10.1039/b916566e. Epub 2009 Nov 30.
We demonstrate a mass-production-amenable technology for fabrication, surface modification and multifunction integration in polymeric microfluidic devices, namely direct lithography on the polymeric substrate followed by polymer plasma etching, and selective plasma deposition. We apply the plasma processing technology to fabricate polymeric microfluidics in poly(methyl methacrylate) (PMMA) and poly(ether ether ketone) (PEEK). First, deep anisotropic O(2) plasma etching is utilized to pattern the polymer via an in situ, highly etch-resistant, thin, Si-containing photoresist, or via a thick organic photoresist. Absolute control of surface roughness (from smooth to very rough), and the production of stable-in-time (slowly ageing) superhydrophilic microchannels are demonstrated. Second, we demonstrate the spontaneous capillary pumping through such rough, superhydrophilic plasma-etched microchannels in contrast to smooth ones, even 5 weeks after fabrication. Third, by using C(4)F(8) fluorocarbon plasma deposition through a stencil mask, we produce superhydrophobic patches inside the microchannels, and use them as passive valves. Our approach proposes "smart" multifunctional microfluidics fabricated by a plasma technology toolbox.
我们展示了一种适用于聚合物微流控器件制造、表面改性和多功能集成的大规模生产技术，即直接在聚合物基底上进行光刻，然后进行聚合物等离子体刻蚀和选择性等离子体沉积。我们将等离子体处理技术应用于聚甲基丙烯酸甲酯（PMMA）和聚醚醚酮（PEEK）的聚合物微流控器件的制造。首先，利用深各向异性 O2等离子体刻蚀，通过原位形成的高耐刻蚀性的薄含硅光刻胶或厚有机光刻胶对聚合物进行图案化。我们展示了对表面粗糙度（从光滑到非常粗糙）的绝对控制，以及稳定的超亲水微通道的制作（缓慢老化）。其次，我们证明了与光滑微通道相比，即使在制造后 5 周，通过这种粗糙的超亲水等离子体蚀刻微通道也可以自发地进行毛细泵送。第三，通过使用带有掩模版的 C4F8氟碳等离子体沉积，我们在微通道内部生成超疏水的斑块，并将其用作无源阀。我们的方法提出了由等离子体技术工具包制造的“智能”多功能微流控器件。
