New perspectives for direct PDMS microfabrication using a CD-DVD laser

A simple and inexpensive alternative to high-power lasers for the direct fabrication of microchannels and rapid prototyping of poly-dimethylsiloxane (PDMS) is presented. By focusing the infrared laser beam of a commercial, low-power CD-DVD unit on absorbing carbon micro-cluster additives, highly localized PDMS combustion can be used to etch the polymer, which is otherwise transparent at such wavelengths. Thanks to a precise and automated control of laser conditions, laser-induced incandescence is originated at the material surface and produces high-resolution micropatterns that present properties normally induced with lasers of much greater energies in PDMS: formation of in situ nanodomains, local fluorescence and waveguide patterns. An extensive study of the phenomenon and its performance for PDMS microfabrication are presented.