Temporal development of the composition of Zr and Cr cathodic arc plasma streams in a N2 environment

Abstract

We describe the temporal development of the plasma composition in a pulsed plasma stream generated by cathodic arc. Cathodes of Zr and Cr were operated at various nitrogen pressures. The time resolved plasma composition for the cathode materials was analysed with time-of-flight charge-to-mass spectrometry, and was found to be a strong function of the nitrogen pressure. Large plasma composition gradients were detected within the first 60 µs of the pulse, the nitrogen ion concentration increasing with increasing pressure. The results are explained by the formation and erosion of a compound layer formed at the cathode surface in the presence of a reactive gas. The average charge state was also found to be affected by the reactive gas pressure as well 1 as by the time after ignition. The charge states were highest in the beginning of the pulse at low nitrogen pressure, decreasing to a steady-state value at higher pressure.These results are of importance for reactive plasma processing and for controlling of the evolution of thin film composition and microstructure.2

Influence of argon and oxygen on charge-state-resolved ion energy distributions of filtered aluminum arcs

“…Reduced ion charge states [7][8][9][10] and ion energies 7,[11][12] have been reported when the pressure was increased. However, most studies deal with average charge states, 7,10 average energies, 7,12 or IEDs averaged over all ion species present.…”

“…However, most studies deal with average charge states, 7,10 average energies, 7,12 or IEDs averaged over all ion species present. 11 Detailed information about the effect of gas on individual charge states including their IEDs is limited: Chhowalla analyzed charge-state-resolved IEDs for zirconium arc plasma before and after introduction of nitrogen, 13 and Bilek et al…”

High quality ZnO:Al transparent conducting oxide films synthesized by pulsed filtered cathodic arc deposition

“…[20,21]. Additionally, the dense zinc arc plasma also causes excitation and ionization of oxygen, and therefore the deposition process is "energetic" [22][23][24] with contributions of both kinetic and potential energy to the film growth process [16,25].…”

Ion charge state fluctuations in vacuum arcs

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