[1] Empa, Lab Mech Mat & Nanostruct, Feuerwerkerstr 39, CH-3602 Thun, Switzerland
[2] Empa, Ctr Xray Analyt, Uberlandstr 129, CH-8600 Dubendorf, Switzerland
[3] Swiss Fed Inst Technol, Ion Beam Phys, Otto Stern Weg 5, CH-8093 Zurich, Switzerland
[4] Oerlikon Metco AG, CH-5610 Wohlen, Switzerland
[5] Oerlikon Surface Solut AG, Iramali 18, LI-9496 Balzers, Liechtenstein