Large photosensitivity in extremely high index contrast SiON waveguides on Si

We demonstrate the photosensitivity of an extremely high index contrast silicon oxynitride waveguide using an arrayed-waveguide grating multi/demultiplexer. We observed a large index change for a 7.7%-? waveguide induced by ArF laser irradiation, which was up to 2.4 x 10 -3 and stable for thermal annealing.