Microstructure fabrication with a CO₂ laser system

In this paper, we investigate the use of a commercial CO2 laser system for fabrication of microfluidic systems in polymers. We discuss the cutting process with the laser system and present a straightforward model for the channel depth of microchannels dependent on the fabrication parameters. In particular, we examine the influence of the cutting sequence, the number of cut passes, the laser beam velocity and the laser radiant flux. The model allows the prediction of microchannel depths within a maximum deviation of 8 µm for channels that are up to 210 µm in depths. It was shown that, at constant channel depth, the channel width could be varied by 27% by using different cutting parameters. The optimum cutting sequence for the production of a channel -junction is also presented in the paper. The laser system is shown to be a flexible and rapid tool for the production of polymer microfluidic prototypes.