Microfabricated plastic devices from silicon using soft intermediates

Nanotechnology is having an enormous impact on many areas of science, including biology. However, its application to mainstream biology is limited by the complexity and expense of fabricating large numbers of silicon devices in nanofabrication facilities that are not readily available to all investigators. Biological experiments require a relatively large number of replicates. We have developed methods to use silicon devices as masters to mold replicas in polymers. Once the silicon master is fabricated, the method can be implemented in a standard biology laboratory. Polystyrene microdevices were fabricated for biological applications. Fabrication of such devices is described using hot embossing with and without vacuum, and by in situ polymerization from partially polymerized styrene monomers in polydimethylsiloxane molds made from silicon masters. Replication of the silicon master features into plastic using the polydimethylsiloxane intermediate mold is highly accurate for micrometer and sub-micrometer features. Preliminary biological experiments using polystyrene replicas have successfully demonstrated the potential of this fabrication method.