LOW-HYDROGEN SILICON OXYNITRIDE OPTICAL FIBERS PREPARED BY SPCVD

The performance of the first samples of nitrogen-doped silica optical fibers, a novel type of optical fiber, is investigated, The fiber preforms containing up to similar to 3 at % of nitrogen in the core have been synthesized by reduced-pressure plasmachemical deposition (SPCVD) and drawn into fibers, By eliminating hydrogen-containing components from the gas mixture, low-hydrogen silicon oxynitride has been obtained, Optical loss in fibers in the range 1.3-1.6 mu m, beyond OH- and NH-group absorption peaks, is several dB/km and, apparently, can be further reduced by optimizing the preparation processes.