Deposition of Ge-doped silica thin films for an integrated optic application using a matrix distributed electron cyclotron resonance PECVD reactor

摘要

Optical quality Ge-doped SiO_2 thin films, suitable for an integrated optic version of a gain equalizer for erbium-doped fibre amplifiers (EDFAs), have been deposited using a matrix distributed electron cyclotron resonance plasma-enhanced chemical vapour deposition (MDECR-PECVD) system. Using spectroscopic ellipsometry and infrared transmission spectroscopy, the optical constants and hydro-xyl content of the films were calculated. Losses due to the hydroxyl overtone at 1.37 μm are found to be approximately 0.251 dB/cm. An RBS analysis determined the germanium content of the films to be in the vicinity of 4 at.%. A comparison of the atomic percentage of germanium in the films and their corresponding refractive indices with values obtained using other deposition methods is also discussed.