Soft lithography fabricated polymer waveguides and 45° inclined mirrors for card-to-backplane optical interconnects

Abstract

Polymer waveguides with 45° mirrors are fabricated by vacuum assisted microfluidic (VAM) soft lithographic technique for card-to-backplane optical interconnect applications. Waveguide array structures with inclined surfaces in SU-8 photoresist for PDMS mold are fabricated by prism assisted UV exposure. Sample surface reflected UV light is utilized to eliminate undercut structures and to accomplish the inclined mirror surfaces on both ends of the straight waveguide segments by one-step UV exposure. Polymer waveguides with 45° embedded mirrors demonstrated about 0.49 dB/cm propagation loss and 67% mirror coupling efficiency.

Low-cost board-to-board optical interconnects using molded polymer waveguide with 45 degree mirrors and inkjet-printed micro-lenses as proximity vertical coupler

“…6.0 dB (0.5 mm transmission line) and 6.4 dB (80 mm waveguide) coupling losses, including two 45 degree mirrors, respectively were reported by Chen [32] and Van Hoe [33]. More recently, Jiang [34] and Inoue [35] reported 1.74 dB and 2.3 dB coupling loss, respectively for one 45 degree mirror. Chang etc [36].…”