Fast measurement of fluorine distribution in doped fused silica by pulsed Raman scattering
in: Physics and Chemistry of Glasses-European Journal of Glass Science and Technology Part B (2009)
We present short time measurements to determine the distribution of fluorine dopant in extended fused silica samples. These measurements are based on pulsed Raman spectroscopy. Our investigations are starting point for a further development of a nondestructive optical in situ method of fluorine detection. A KrF excimer laser (248 nm) of narrow bandwidth was used to excite the vibrational transitions of Si–F (940 cm−1) and Si–O groups (809 cm−1). The fluorine concentration at a reference sample was determined by WDX-analysis to calibrate the intensity ratio of the Si–F and the Si–O vibrational bands. We investigated extended dry fused silica samples with a known fluorine concentration ≤10000 wt ppm. The detection limit amounts to 2000 wt ppm.