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The $SiF2$ radical is an important intermediate in the plasma etching of silicon in fluorocarbon plasmas, a widely used semiconductor device fabrication process. We report tunable dye laser fluorescence and tunable diode laser infrared absorption spectra of $SiF2$, taken as part of a program of development of laser diagnostics for such processes. We also used these diagnostics in a fast flow reactor to measure the kinetics of $SiF2$ reactions with F and $F2$. The chemiluminescence observed during plasma etching has been attributed to these $reactions,1$ although some doubt $remains.2$ The similarity in activation engergies for the emission and etching has been used as deciding evidence in a detailed model of the etching process. We will present results on the chemiluminescent spectrum from the reaction of F and $F2$ with $SiF2$ formed from two different sources, $SiF4$ passed over hot Si, and thermal decomposition of $Si2F6$.