Templateless prototyping of polydimethylsiloxane microfluidic structures using a pulsed CO2 laser

We present a novel process (through cutting and pattern transfer processes) for rapidly prototyping polydimethylsiloxane (PDMS) microfluidic structures without a replication template using a CO2 laser. The process typically takes less than 30 min to make a PDMS microfluidic chip from idea to device. In addition to time saving, the process also drastically cuts down equipment and operating costs by eliminating the use of masks, templates, wafer fabrication equipment and consumables needed in the template-making process. We further demonstrate the capability of the process in the rapid prototyping of a variety of microstructures from a 2 µm thin layer up to a 3.6 mm high structure on a single PDMS layer with accurate thickness control as well as smooth top and bottom surfaces. Various process characteristics and challenges for the PDMS laser prototyping process are addressed in this note.