Some of the fundamental properties of the NF3etchant gas discharge were investigated. The dissociation of the parent gas molecules was inferred using mass spectrometric methods, and it was found that the discharge is much more effective at dissociating NF3than CF4. Furthermore, the percentage dissociation of the NF3was extremely large, ∼50%. Using a pulsed discharge it was possible to observe the time evolution of the dissociation products. These studies have led to a mathematical description of the dissociation and product formation kinetics.