Laser annealing of Corning 7059 glass waveguides

Corning 7059 glass thin film waveguides prepared by rf sputtering and vapor deposition were annealed with a CO(2) laser at various powers and scan velocities. Some reduction in optical loss was observed after laser annealing of the films. The results show a reduction in optical loss with the number of laser scans. Optical profilometer measurements indicated no change in surface roughness after laser annealing. RBS analysis of laser annealed samples show no change in elemental composition. We discuss possible optical loss reduction mechanisms and present data on the marking of thin films when annealing is done at higher CO(2) laser powers.