Development of a library of low-loss silicon-on-insulator optoelectronic devices

Established silicon microelectronics fabrication methods can be exploited to fabricate low-loss silicon integrated optical devices of dimensions which are compatible with single mode fibres and operate at the important wavelengths of 1.3 and 1.5 μm. Recent advances at the University of Surrey, where research effort in this field has been to develop a library of optoelectronic components, is highlighted. So far, rib and planar waveguides, including bends and Y-junctions, have been produced, together with design and fabrication of efficient optical modulators based on the plasma dispersion effect. Within the experimental error, the waveguide losses are indistinguishable from the intrinsic absorption loss of pure silicon. The figure of merit for the modulators is greater than 200°/V/mm and the operating current is 7 mA, which improves on previous devices by approximately an order of magnitude