Reactive magnetron sputtering: from fundamentals to high deposition rate processes
2013 (English)In: Proceedings of the Twelfth th International Symposium on Sputtering & Plasma Processes ISSP 2013 / [ed] Yasuhito Gotoh, 2013, 5-9 p.Conference paper, Abstract (Refereed)
Reactive magnetron sputtering is widely used for synthesis of various compound thin films. The technique is very versatile and scalable. Especially in industry, high productivity is essential and there is a need for processes with high deposition rates. Achieving high deposition rate and true compound stoichiometry of the deposited film is, however, challenging in reactive sputtering. As a consequence of complex interaction between the reactive gas and the sputtered metal, the relation between deposition rate or composition of the coating and flow of reactive gas is very non-linear and usually exhibits hysteresis behaviour.
This contribution deals with modelling based development of reactive sputtering processes. First, the basic model of reactive sputtering is briefly reviewed. A steady state model is derived, discussing the most important assumptions and illustrating the physical processes taking place in reactive sputtering. The model is then used to discuss some strategies for high deposition rate processes, such as using high pumping speed or substoichiometric targets. Another strategy for increased deposition rate employs sputtering yield amplification. Here, the sputtering target is doped by a heavy element in order to reduce the depth of collision cascades thus increasing the sputtering yield of target. This technique is suitable for reactive sputtering of oxides as demonstrated for reactive deposition of Al2O3 with W doping. In this case, the deposition rate may be increased by about 100% as confirmed experimentally.
Although reactive sputtering is well understood, recent research on reactive High Power Impulse Magnetron Sputtering (HiPIMS) brought some intriguing experimental results. In order to develop a comprehensive model applicable to reactive HiPIMS, more accurate description of the individual effects taking place in sputtering is essential. As a first step towards such a model, discharge current behaviour in reactive HiPIMS is analysed. It is shown that in HiPIMS, the discharge behaviour is strongly influenced by ionized particles sputtered from the target.
Place, publisher, year, edition, pages
2013. 5-9 p.
, International Symposium on Sputtering & Plasma Processes, ISSN 2187-7637
Manufacturing, Surface and Joining Technology
Research subject Engineering Science with specialization in Electronics
IdentifiersURN: urn:nbn:se:uu:diva-204426OAI: oai:DiVA.org:uu-204426DiVA: diva2:653163
Invited talk: 12th International Symposium on Sputtering and Plasma Processes, July 10-12, 2013, Kyoto