Fabrication of microstructures for modeling transport in porous materials

Silicon micromachining was used to fabricate microstructures for modeling transport in porous systems. A linear network of pores connected by narrow channels was etched into silicon to create constricted pore networks. The use of micromachining enables the creation of structures having the same characteristic dimensions as the pore networks found in polymeric controlled release systems. A two mask process was developed to reduce undercutting of convex corners during the anisotropic etching of the silicon. Initial studies of the release of a fluorescent dye out of the micromachined pore network are presented.