Electron Impact Ionization of SiCl3, SiCl2, and SiCl

The interactions of electrons with matter are among the most fundamentally important processes in nature. Electron impact ionization and dissociative processes, and in particular, electron impact induced processes involving halogen-containing molecules, are crucial in low-temperature processing plasmas. To control the characteristics of the materials processed by the plasma, knowledge of the equilibrium number density of the different reactive species in the plasma is essential. There is therefore a critical need for cross sections of electron-impact induced processes relevant to the creation and destruction of these species. Silicon tetrachloride (SiCl4) is frequently used as an admixture in processing plasma feed gas mixtures. The electron impact ionization and dissociative ionization cross sections for the SiCl4 molecule as well as for the resulting from the collisional break-up of SiCl4 initiated by the plasma electrons are very important quantities for the understanding and modeling of silicon-chlorine plasmas and their interactions with materials. In this thesis, the electron impact ionization of SiCl3, SiCl2, and SiCl is investigated.