Abstract We report on femtosecond laser direct writing of electrically conductive copper structures on transparent cyclic olefin copolymer based planar optical chips. The process is based on a laser-induced reduction of CuO nanoparticles dissolved in a water-soluble resin. Thus generated conductive copper structures are characterized with respect to their chemical composition and electrical resistivity. In addition, the application of ultrashort laser pulses enables a hybrid micromachining approach comprising ablation of polymer substrates and the fabrication of copper patterns in a single laser processing setup. A possible electro-optical application of this approach is demonstrated by employing the copper structures as an electro-thermal microheater in combination with a polymer planar optical Bragg grating sensor. This, in turn, highlights the potential of generating copious micro-opto-electro-mechanical polymer structures for numerous sensing applications ranging from Lab-on-Chip to environmental applications using the presented hybrid micromachining approach.

中文翻译：

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基于飞秒激光的聚合物微光电系统混合微加工

摘要 我们报告了基于透明环烯烃共聚物的平面光学芯片上导电铜结构的飞秒激光直写。该过程基于激光诱导还原溶解在水溶性树脂中的 CuO 纳米粒子。由此产生的导电铜结构的特征在于它们的化学成分和电阻率。此外，超短激光脉冲的应用实现了混合微加工方法，包括在单个激光加工装置中消融聚合物基板和制造铜图案。通过将铜结构用作电热微加热器并结合聚合物平面光学布拉格光栅传感器，证明了这种方法的一种可能的电光应用。这反过来，