Porous silicon on insulator: a new approach to fabricate porous silicon based optoelectronic devices

A new fabrication technique of laterally anodized porous silicon is presented. This technique, when applied to bulk silicon wafers, generates a uniform pattern of light emitting porous silicon with high quality smooth interfaces with the surrounding silicon. Additional improvement is achieved by using silicon-on-insulator wafers. In this case, a backside gate contact allows electrical control of the anodization process and a fabrication of porous silicon on insulator structures. It is show that this technique is capable of producing optical waveguide structures with smooth interfaces and high confinement of the optical mode to the porous silicon layers. Optical and structural characterizations of the porous silicon on insulator structure are presented demonstrating uniform, low loss optical waveguides.