Self-alignment technique for fiber attachment to guided wave devices

We propose and demonstrate a new multiple fiber-waveguide alignment technique suitable for single-mode and multimode guided wave devices. The method uses an overlap between a precision-etched silicon substrate and the top surface of the waveguide substrate to align all but one of the six degrees of freedom automatically. We have attached six arrays, each with twelve single mode fibers, and have measured an average excess loss of 0.9 dB at \lambda = 1.3 \mu m. The lowest loss array had an average excess loss of 0.4 dB.