Relative Cross Sections for Electron‐Impact Dissociation of SF6 into SFx (x = 1−3) Neutral Radicals

The energy dependence of the partial cross sections of electron‐impact dissociation of SF6 into the neutral radicals SF, SF2 and SF3 is measured from the threshold to 200 eV. This measurement is accomplished by appearance mass spectrometry in a dual electron beam device. The dissociation products SF4 and SF5 are below the detection limit of the present system. The threshold energies for neutral dissociation into SF3, SF2 and SF are measured to be 16.0, 19.5 and 22.0 eV respectively. The surface loss probability of each radical and the electron‐impact nitrogen dissociation are examined to evaluate the relative dissociation cross section. However, the absolute cross section cannot be assigned for lack of the ionization cross sections for the SFx radicals.