Detection of Fluorine with a Shock Wave Plasma Induced by a TEA CO₂ Laser

Abstract

A new method is presented for detecting fluorine atoms with a shock wave plasma induced by bombardment of a TEA CO₂ laser beam. Comparison is made between a fluorine neutral emission line (FI 685.6-nm) and a fluorine ionic emission line (FII 385.0-nm) on the pressure dependence and the spatial distribution. The detection limits of FI 685.6-nm line and FII 385.0-nm line are 100 ppm and 900 ppm, respectively. The background equivalent concentration (BEC ) are 0.015% for FI 685.6-nm and 0.02% for FII 385.0-nm. The present method is of great advantage to the direct measurement of solid samples and to reduce sample preparation procedures.