Micromolding in capillaries (MIMIC) has been used to fabricate arrays of single-mode polymeric waveguides from several classes of polymeric materials (epoxies, polyurethanes, and polyacrylates) supported on Si/SiO2 substrates. Waveguides clad with polymers having slightly lower refractive indices gave single-mode output in the visible and near-infrared regions. A typical waveguide structure exhibiting single-mode behavior is shown in the Figure.