CONCENTRATION PROFILES OF CF IN A CF4 RADIO-FREQUENCY DISCHARGE VIA LASER-INDUCED FLUORESCENCE AND ACTINOMETRY

We have measured the steady state, axial concentration profiles of the CF radical in a symmetric, parallel plate, 13.56 MHz discharge in CF4 (with 5% Ar) using both laser induced fluorescence (LIF) and actinometry. The two lowest vibrational levels of the ground electronic state (X) of CF were probed with LIF and the two lowest vibrational levels of the B electronic state were observed in emission for actinometry. The LIF profiles, and thus, the X state concentration profiles, were both nearly flat in the bulk of the discharge. The B,upsilon'-0 actinometric profile was sharply peaked, while the upsilon' = 1 was nearly flat. Therefore, spatially resolved actinometry works for the B,upsilon' = 1 level of CF but not for upsilon' = 0, under the discharge conditions studied.