Laser‐induced fluorescence of CF2is used to monitor heterogeneous processes in ≊300 mTorr CF4/O2plasmas. CF2is rapidly removed at fluorinated copper and silver surfaces in 13.56‐MHz rf discharges as judged by a distinct dip in its spatial distribution. These metals, when employed as etch masks, are known to accelerate plasma etching of silicon, and the present results suggest catalytic dehalogenation of CF2is involved in this process. In contrast, aluminum and silicon dioxide exhibit negligible reactivity with CF2, which suggests that aluminum masks will not appreciably accelerate silicon etching and that ground state CF2does not efficiently etch silicon dioxide. Measurement of CF2decay in a pulsed discharge coupled with direct laser sputtering of metal into the gas phase indicates the interaction between CF2and the active metals is purely heterogeneous. Aluminum does, however, exhibit homogeneous reactivity with CF2. Redistribution of active metal by plasma sputtering readily occurs; silicon etch rates may also be enhanced by the metal’s presence on the silicon surface. Polymers contribute CF2to the plasma as they etch. The observation of an induction period suggests fluorination of the polymer surface is the first step in its degradation. Polymeric etch masks can therefore depress the silicon etch rate by removal of F atoms, the primary etchants.