Assembly of mechanically compliant interfaces between optical fibers and nanophotonic chips

Silicon nanophotonics may bring disruptive advances to datacom, telecom, and high performance computing. However, the deployment of this technology is hampered by the difficulty of cost efficient optical inputs and outputs. To address this challenge, we have recently proposed a low-cost, mechanically compliant polymer interface between standard single mode fibers and nanophotonic waveguides. Our concept promises better mechanical reliability and better optical performance than existing technology. To manage the cost of assembly, we show here that self-alignment features can be effectively used to bridge the gap between the accuracy required by single-mode optics (1-2 um) and the capability of high-throughput microelectronic assembly equipment (~10 um). We describe the complaint interface, the assembly strategy, and the design of our re-alignment features. We demonstrate experimentally that misalignments at assembly as large as +/-10 um are re-aligned by our self-alignment structures to +/-1 to 2 um. Our approach enables existing microelectronics equipment to be used for singlemode optics assembly.