AVS 57th International Symposium & Exhibition
    Advanced Surface Engineering Tuesday Sessions
       Session SE-TuM

Paper SE-TuM10
Al-Si-N-O Hard Coatings Prepared by Reactive Magnetron Sputter Deposition from Composite Targets

Tuesday, October 19, 2010, 11:00 am, Room Cimmaron

Session: Hard and Nanostructured Coatings
Presenter: J. Patscheider, Empa, Switzerland
Authors: J. Patscheider, Empa, Switzerland
M. Parlinska-Wojtan, Empa, Switzerland
A. Pélisson, Empa, Switzerland
P. Polcik, Plansee Composite Materials GmbH, Germany
P. Pecher, Glas Troesch AG, Switzerland
Correspondent: Click to Email
The applicability of hard nitride coatings on a large industrial scale often depends on the sensitivity of their properties on oxygen contaminations. Following the experience of reactive magnetron sputter deposition of optically transparent Al-Si-N thin films by co-sputtering from two elemental targets in a confocal arrangement, the possibility to prepare similar films from powder metallurgical Al-Si targets of different Al/Si ratios in mixed Ar-N2-O2 is investigated. This arrangement is especially interesting when such coatings have to be prepared on an industrial scale. In this work, the effect of oxygen on the coating properties is examined, as reactive elements like Al often cause oxygen to be incorporated as a contamination. It is shown that hardness values up to 28 GPa are reached at oxygen concentrations of several atomic percent. The deliberate addition of O2 to the reactive gas mixture of Ar/N2 leads to the incorporation of oxygen up to 20 atomic %. Despite these very high concentrations hardness values of 25 GPa are reached. Similar to silicon, oxygen additions cause grain refinement and a gradual disappearance of the columnar structure with increasing oxygen content. It is shown that the hardness is primarily influenced by the plasma density and to a lower extent by other factors like silicon content and preferred orientation.