A novel laser micromachining method is presented that utilizes a microfabricated silicon stencil and a CO2 laser for low-cost high-resolution machining of polymer substrates. With this laser stenciling method, arrays of microchannels and microholes were patterned in poly(dimethylsiloxane) (PDMS) and Kapton® films. Minimum recorded feature sizes patterned in these films were 8.4 and 12.6 µm, respectively, using a stencil opening of 25 µm. Different stencil sidewall configurations were investigated to determine the effect of such topographies on the resulting polymer patterns. An example multi-layer microfluidic device, comprised of PDMS layers with stenciled features, is presented to demonstrate the direct, single-step polymer microfluidic channel fabrication capability of this technique. The method presented here is suitable for low-cost and medium-volume rapid polymer microdevice production while overcoming the low-resolution limit of CO2 laser micromachining.
Longsine-Parker, W., A. Han
Journal of Micromechanics and Microengineering