The electron impact dissociation of molecular fluorine in XeF and KrF excimer lasers is examined. Two methods of dissociation are discussed: dissociative attachment and direct neutral dissociation by excitation to the dissociative electronic states a3Πu and A1Πu. Computer models for the kinetics of the lasers are parameterized, and predictions of electron density are compared to experimental results for electron beam pumped Ne/Xe/F2 gas mixtures [W. D. Kimura, D. R. Guyer, S. E. Moody, J. F. Seamans, and D. H. Ford, Appl. Phys. Lett. 50, 60 (1987)]. To obtain agreement with experiment, the ratio of direct dissociation to dissociative attachment must be ≥2. The implications of these results with respect to electron quenching and the validation of computer models are discussed.