On the description of metal ion return in reactive high power impulse magnetron sputtering

• Published in: Surface & coatings technology Vol. 418; p. 127234
• Main Authors: Kubart, T., Fernandes, D.F., Nyberg, T.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 25.07.2021; Elsevier BV
• Subjects: Magnetron sputtering; Metal back-attraction; Photovoltaic cells; Process modelling; Reactive HiPIMS; Reactive sputtering; Steady state models; Thin films; Thin films; Process modelling; Reactive sputtering; Reactive HiPIMS; Metal back-attraction
• ISSN: 0257-8972; 1879-3347; 1879-3347
• DOI: 10.1016/j.surfcoat.2021.127234

Back-attraction of ionized metal is an important process in reactive high power impulse magnetron sputtering (R-HiPIMS). Here, we discuss the implementation of the metal return in balance type models for reactive magnetron sputtering. We show that the existing description of surface processes needs to be modified to satisfy mass conservation. A new steady-state time-averaged model is presented and used to evaluate the effect of the metal return in R-HiPIMS. The results show that the metal return leads to an increased oxide fraction in the deposited coating in R-HiPIMS. This effect can explain the high rate deposition of stoichiometric compounds deposited in the metal mode of operation that has been observed experimentally. •Metal back-attraction in reactive HiPIMS studied.•New description for target surface processes developed.•Hysteresis in reactive HiPIMS process simulated.•A process window for synthesis of stoichiometric oxides identified.