Multimode waveguide with a 45 degree mirror is fabricated by a rubber-molding process. A thick photoresist AZ9260 is used in patterning the master and the rubber mold of the pattern is fabricated with a PDMS elastomer. The waveguide has dimensions of 50㎛×50㎛. For the replication to polymer, WG-25 and NOA73, UV-curable epoxy are used. The propagation losses are measured to be 0.9 dB/cm for WG-25 and 0.4 dB/cm for NOA73 at the wavelength of 850 nm. A method of fabricating 45 degree mirrors at the end of these waveguides by tilting the sample and illuminating UV is proposed. To measure the loss of a mirror, a backside of silicon wafer is wet-etched. The measured loss of a mirror is about 0.9 dB.
