Glass integrated optical devices on silicon for optical communications

Silica-on-silicon integrated optics is a key technology for passive optical components, as required for the next generation of fibre optics communications systems. This paper reviews progress on silica-on-silicon technology and key devices developed to date. Waveguide fabrication technology is described, with particular attention to deposition processes. Fibre pigtailing technology is described, and the relative merits of active and passive alignment are discussed. A range of passive components are detailed, concentrating on couplers, splitters and wavelength division multiplexers. Recent developments in rare-earth doping of silica-on-silicon waveguides are also covered. The paper concludes with some discussion on future directions for silica-on-silicon research and development.