Abstract

Laser microprocessing for microfluidics application

Zhongke Wang , Research Scientist, Singapore Institute of Manufacturing Technology (SIMTech), A*Star

Microfluidic channel designs are generally according to the particular requirements of each application. It is frequently necessary to modify the channel design in order to optimize the performance of a microfluidic device. Laser techniques may provide a high level of flexibility in microfluidic manufacturing because they directly use digital data generated in designing of microfluidics. It allows the iterations of the design and fabrication of microfluidics with improvements in short time cycle and cost effectiveness. This talk wish to introduce you some results completed in SIMTech on 1) Rapid prototyping of microfluidic channels using laser direct writing on polymer substrates, 2) Possible method of smoothing of microfluidic channels fabricated on polymer PMMA substrates using lasers and, 3) Laser surface engineering for microfluidics application which includes laser tailoring of wettability of microchannel surfaces and laser texturing of insert micromold surfaces. Laser rapid prototyping microfluidic channels with respect to different laser systems such as long wavelength CO2 laser (10.6 µm), UV excimer laser (248 nm) and femtosecond laser (775 nm, 150 fs) will be introduced. Controlled modification of surface wettability for separation ratio and/or mixing ratio of samples in different microchannels will be discussed. Some promising results on surface texturing of the hot-embossing mold substrates (Ni, Stavax) for controlled wettability modification will be discussed. A few microfluidic chips fabricated using laser direct writing will be demonstrated.