Decoupling the effects of potential energy, kinetic energy, and ion flux on crystallinity of V-Al and V-Al-N thin films in pulsed filtered cathodic arc deposition

Abstract

Deposition using filtered pulsed cathodic arc plasma is known to produce dense and adherent thin films due to energetic ions which carry significant ion kinetic and potential energies. The role of potential energy coming from multiply charged metal ions in film formation remains under-explored, since the enhancement of charge states in cathodic arcs is coupled with an increased flux and kinetic energies of ions. In this work, the influence of ion potential energy on structural properties of thin films is investigated, while keeping the mean ion kinetic energies unchanged. Two material systems are considered: metallic V-Al and compound V-Al-N in non-reactive and reactive deposition, respectively. For V-Al plasma and thin films, the impact of metal ion potential energy is demonstrated. In the V-Al-N case, in addition to metal ions, activated (namely, ionized, dissociated, and excited) nitrogen species are found to be a significant factor for crystalline growth of the metastable cubic phase.