Mechano-optical waveguide on-off intensity modulator.

High-extinction on-off modulators are essential for channel selection in integrated-optical sensor arrays. We report a standard SiON-technology-based electrostatically driven integrated mechano-optical waveguide on-off intensity modulator. On-off modulation is achieved by movement of an absorbing element into and out of the evanescent field of the guided mode. An extinction ratio of >37 dB at an actuation voltage of <30 V was achieved in a 6 mm x 4 mm device for a wavelength of 632.8 nm. Full wafer-scale fabrication is made possible by use of chemical mechanical polishing and aligned wafer bonding.