TY - CONF A1 - Roth, Gian-Luca A1 - Wolf, Bastian A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Generation of internal 3D microfluidic architectures in polymers by fs laser processing T2 - Lasers in Manufacturing 2019 N2 - Microfluidic lab on chip systems require components to transport, mix, separate and analyse small volumes of different fluids. In this study, we report on the laser generation of internal hollow architectures created by focused 514 nm femtosecond laser pulses inside PMMA bulk material. Size and cross-sectional shape of a single internal generated microchannel are determined by the intensity distribution inside the focal voxel and can be controlled either by the numerical aperture of the focusing objective or by laser beam shaping. As both approaches are practically limited with respect to the realizable cross-sectional shapes, we present a process based on an internal hatching to expand the achievable channel cross-sections and thereby enable the possibility to create complex 3D shaped internal structures. This process is applied to create fully internal functional microfluidic elements such as mixers which are part of most polymer lab-on-chip systems. KW - Femtosekundenlaser Y1 - 2019 UR - https://opus4.kobv.de/opus4-h-ab/frontdoor/index/index/docId/1578 ER -