Picture for: How do you make a microreactor?
(Note: source has © on the figure)
Here's a diagram of the process for producing the second generation silicone stamper. Poly(dimethylsiloxane) (PDMS) is used as it is a liquid at room temperature but converts into a solid elastomer when cross-linked. The deformations of the cured PDMS allow for the molding of elaborate three dimensional third generation microreactors.
Source: Xia Y, Whitesides GM. 1998. Annual Reviews of Material Science. 28:153-184.