Since polydimethylsiloxane (PDMS) is notorious for its severe sorption to biological compounds and even nanoparticles, thermoplastics become a promising substrate for microdevices. Although CO2 laser engraving is an efficient method for thermoplastic device fabrication, it accompanies with poor bonding issues due to severe bulging and large feature size determined by the diameter of laser beam. In this study, a low-cost microfabrication method is proposed by reversibly sealing a 1 mm thick polymethylmethacrylate (PMMA) over an engraving substrate to reduce channel feature size and minimize bulges of laser engraved channels. PMMA, polycarbonate (PC), polystyrene (PS), perfluoroalkoxy alkane (PFA), cyclic-olefin polymers (COP) and polylactic acid (PLA) were found compatible with this sacrificial layer assisted laser engraving technique. Microchannel width as small as ∼40 μm was attainable by a laser beam that was 5 times larger in diameter. Bulging height was significantly reduced to less 5 μm for most substrates, which facilitated leak proof device bonding without channel deformation. Microdevices with high aspect ratio channels were prepared to demonstrate the applicability of this microfabrication method. We believe this fast and low-cost fabrication approach for thermoplastics will be of interest to researchers who have encountered problem with polydimethylsiloxane based microdevices in their applications.

中文翻译：

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一种用于六种类型的热塑性基材的快速低成本微加工方法，使用牺牲层辅助激光雕刻减少了特征尺寸并最大限度地减少了凸起

由于聚二甲基硅氧烷 (PDMS) 因其对生物化合物甚至纳米颗粒的严重吸附而臭名昭著，因此热塑性塑料成为微器件的有前途的基材。尽管 CO2 激光雕刻是一种有效的热塑性设备制造方法，但由于严重的膨胀和由激光束直径决定的大特征尺寸，它伴随着不良的粘合问题。在这项研究中，提出了一种低成本的微细加工方法，通过在雕刻基板上可逆地密封 1 毫米厚的聚甲基丙烯酸甲酯 (PMMA)，以减小通道特征尺寸并最大限度地减少激光雕刻通道的凸起。PMMA、聚碳酸酯 (PC)、聚苯乙烯 (PS)、全氟烷氧基烷烃 (PFA)、环烯烃聚合物 (COP) 和聚乳酸 (PLA) 被发现与这种牺牲层辅助激光雕刻技术兼容。通过直径大 5 倍的激光束可以获得小至 40 μm 的微通道宽度。对于大多数基板，凸出高度显着降低至 5 μm 以下，这有助于防漏器件粘合而不会发生通道变形。制备具有高纵横比通道的微器件以证明这种微制造方法的适用性。我们相信这种快速且低成本的热塑性塑料制造方法将引起在应用中遇到聚二甲基硅氧烷微器件问题的研究人员的兴趣。制备具有高纵横比通道的微器件以证明这种微制造方法的适用性。我们相信这种快速且低成本的热塑性塑料制造方法将引起在应用中遇到聚二甲基硅氧烷微器件问题的研究人员的兴趣。制备具有高纵横比通道的微器件以证明这种微制造方法的适用性。我们相信这种快速且低成本的热塑性塑料制造方法将引起在应用中遇到聚二甲基硅氧烷微器件问题的研究人员的兴趣。