The feasibility of a full low temperature process, based on Plasma Enhanced Chemical Vapor
Deposition, for the fabrication of low loss silica-based optical waveguides is investigated.
Results from XPS, FTIR, ERDA, isochronal wet etch rate, prism coupler measurements show
that (low frequency) RF power is a critical parameter to improve microstructural properties of
2 and minimize Rayleigh scattering. Ge doping of the silica matrix in the
core layer increases network disorder and point defects density, mainly due to the highly
reactive characteristics of the employed gas precursor (germane) and the high sticking
coefficients of its radicals. Measurements on fabricated optical waveguides show that for
relative refractive index differences between core and cladding up to 0.75%, the optical
losses are acceptable for the fabrication of high performance devices.