Integrated waveguide turning mirror in silicon-on-insulator

Planar lightwave circuits based on silicon are playing an important role in integrated optical systems. The integrated waveguide turning mirror (IWTM) is an essential component for the compactness of optical devices. We have designed such a mirror with a 90/spl deg/ directional change in silicon-on-insulator (SOI). The fabricated mirror has very small surface roughness. The loss caused by transverse tilt /spl delta//sub t/ and lateral tilt /spl delta//sub l/ is negligible in theory. A 1 /spl times/ 2 beam splitter using the structure is fabricated to test the performance, and turning mirrors of excess loss less than 0.5 dB/mirror are obtained.