Abstract
It is demonstrated that the refractive-index-controllable nature of luminescent porous silicon (PS) is directly applicable to the development of a three-dimensionally buried optical waveguide. The PS waveguide is fabricated on a p-type silicon wafer by monolithic processes such as photolithography, ion implantation, anodization, and thermal oxidation. An induced high contrast of refractive indices leads to efficient confinement and propagation of visible light. When the active core layer is partially excited by a He-Cd (325 nm) laser, blue emission is observed from a cleaved facet. The PS waveguide is potentially useful as a component of silicon-based photonic integration.