Description
High power impulse magnetron sputtering is a new and promising physical vapor deposition technique. In this technique, differently from DC magnetron sputtering, the use of proper voltage pulses, in the microsecond regime, leads to the formation of a plasma population made of sputtered species in addition to the usual Ar ones. The evolution of such plasma plays a pivotal role in determining the features of the growing film. Thanks to the presence of the metal ion population, the deposition of more compact and crystalline films, as well as formation of compounds at low temperature, is possible [1]. If, on one side, this technique is very promising, on the other many parameters determine the generation of a so complex plasma (e.g. pulse features, magnetic field, gas composition, pressure, etc.) and their role need to be understood. To properly investigate this phenomenon, a multi technique approach is presented focused on metallic and nitride nanomaterials for energy applications [2]. The features of the grown films (morphology and crystallinity) are studied using a material science approach, by SEM and XRD, allowing to link materials feature and process parameters. Then plasma is characterized by OES determining the generated ionic species and monitoring the plasma current during the voltage pulse. The composition of such current is modelled by means of an Ionization Region Model [3,4] that allows the prediction of temporal evolution of every single species. Combining the data it’s possible to envisage the evolution of plasma. This, in turn, allows to predict the coating growth conditions depending on the composition of the impinging ion flux.
Reference:
[1] J. T. Gudmundsson, N. Brenning, D. Lundin, et al., J. Vac. Sci. Technol. A, 30, 2012
[2] L. Bana, et al., Surface and Coatings Technology, 514, 2025, 132544
[3] J.T. Gudmundsson, et al., Plasma Sources Sci. Technol. 25 (6), 2016, 065004
[4] M.A. Raadu, et al., Plasma Sources Sci. Technol. 20 (6), 2011, 065007