Influence of Helium Ion Implantation on Optical Properties of Fused Silica

High-purity fused silica has been implanted with 60-keV helium ions at the fluence of 1.5·1017 cm–2. The effects of helium-ion implantation on optical properties of silica samples before and after helium implantation have been investigated by infrared (IR), photoluminescence (PL), and ultraviolet-visible (UV-vis) spectrophotometer. After helium-ion implantation, X-ray photoelectron spectroscopy (XPS) results indicate that Si 2p peak is shifted to higher binding energy. An obvious PL band at 500 nm is observed, and the PL intensity is significantly decreased. However, the intensity of IR and optical absorption is increased greatly by ion implantation. A mechanism for the effects of helium implantation on optical properties of fused silica is discussed.