Fabrication of Microchannels on Transparent PMMA Using CO2 Laser (10.6 μm) for Microfluidic Applications: An Experimental Investigation

In this research work, microchannel fabrication on PMMA (Polymethyl-methacrylate) using a CO2 laser has been investigated thoroughly. Microchannels have been created on PMMA of diverse aspect ratio. Due to Gaussian nature of beam, the channel cross-section also possesses the near Gaussian shape. The optical properties of PMMA have been investigated using Far-infrared spectroscopy and micro-hardness test has been carried out to verify the presence of softened zone adjacent to laser ablated microchannels. To investigate the effects of individual parameters on microchannel fabrication, 27 numbers of experiments have been performed using full factorial method. Mathematical modeling of each parameter has been performed using nonlinear regression analysis of each factor. The effect of each input parameter viz. laser power, scanning speed and number of pulses per linear inch has been discussed on each microchannel characteristics. Multi-objective optimization has been performed based on desirability function. The results of this work will be further useful in developing fundamental theoretical models for laser ablation of microchannels on PMMA.