AVS 59th Annual International Symposium and Exhibition
    Advanced Surface Engineering Tuesday Sessions
       Session SE+PS-TuM

Paper SE+PS-TuM10
Cathodic Arc Plasma of AlCr Composite Cathodes in Inert and Reactive Atmospheres

Tuesday, October 30, 2012, 11:00 am, Room 22

Session: Pulsed Plasmas in Surface Engineering
Presenter: R. Franz, Lawrence Berkeley National Laboratory
Authors: R. Franz, Lawrence Berkeley National Laboratory
J. Wallig, Lawrence Berkeley National Laboratory
P. Polcik, PLANSEE Composite Materials GmbH, Germany
A. Anders, Lawrence Berkeley National Laboratory
Correspondent: Click to Email
In the past, the distributions of ion charge states of vacuum arcs have been studied in great detail under various conditions, including their dependence on arc current level, strength of a magnetic field (if present), pressure and kind of background gases, and the distance from the plasma-producing cathode spots. Most of the work was done using pure elementary cathodes since the presence of two or more elements in the cathodes would most likely further complicate the situation when studying the physics of cathodic vacuum arcs. However, in many practical applications ternary or quaternary thin films are used. For their synthesis it is common to employ composite cathodes consisting of the elements of interest.

In the field of hard and wear-resistant coatings, thin films based on the system aluminium and chromium represent the state of the art. With the addition of nitrogen and/or oxygen ceramic coatings covering a wide compositional range can be synthesised. In the present study, a time-of-flight spectrometer was used to investigate the arc plasma composition in terms of elemental and ion charge state composition when using AlxCr1-x (0≤x≤1) composite cathodes in different gaseous environments, i.e. in vacuum as well as argon, nitrogen and oxygen atmosphere. The observed ion distributions were interpreted in the established framework of plasma generation at cathode spots and ion-gas interactions.