High temperature proton implantation induced photosensitivity of Ge-doped SiO2 planar waveguides

The possibility of using keV proton implantation at 800 degrees C to enhance the photosensitivity of Ge-doped silica has been investigated. Room temperature implantation induced defects indicated by absorption at ultraviolet (UV) (<200 nm) and visible wavelengths (>550 nm) were annealed during implantation at 800 degrees C to leave stable photosensitive neutral oxygen vacancy (NOV) centers with an absorption peak at similar to 240 nm. The stable NOV defects were photochemically bleached after UV exposure, a process which is accompanied by a change in UV absorption. Positron annihilation spectroscopy demonstrated the effectiveness of implantation at 800 degrees C in annealing the implantation induced damage.