DOPED SOL-GEL FILMS FOR SILICA-ON-SILICON PHOTONIC COMPONENTS

Further expansion of optical communication systems depends strongly on the development of cheap component technologies for functions such as switching, demultiplexing and amplification. Silica-on-silicon is inc reasingly recognised as the best approach to low cost integrated optic s for such applications, but so far the functionality is limited. The purpose of NODES, a basic research collaboration sponsored by the Euro pean Union under the programme ESPRIT, has been to examine the applica tion of sol-gel to a highly functional silica-on-silicon technology. I n particular, the project has investigated film processing and charact erisation, rare-earth doping for amplification, and semiconductor nano crystallite doping for nonlinear functions. This paper presents the ba ckground and context to this work, summarises the technical results ob tained, and discusses requirements and challenges for successful appli cation of sol-gel in photonics.