ION-BEAM MIXING AT COPPER ALUMINA INTERFACES USING MARKER GEOMETRY/

In the present paper results on ion beam effects such as ion beam mixi ng, radiation enhanced diffusion (RED) and phase stability in Cu/Al2O3 marker interfaces are presented. Cu/Al2O3/Cu samples with marker geom etry were prepared by vapor deposition of copper and alumina on polish ed glassy carbon and single crystal silicon substrates. The top Cu lay er had a thickness of 70 nm and the marker thickness was 2.5 nm. In ca se of the Al2O3/Cu/Al2O3 samples a 2.5 nm Cu marker followed by an amo rphous alumina layer with a thickness of 110 nm and a density of 2.9 g /cm(3) were deposited on single crystal alumina substrates. The marker samples were irradiated with 150 keV Ar+ ions. Ion doses were in the range of 1.1 X 10(16) to 5.4 X 10(16) Ar+/cm(2). The sample temperatur e was varied between room temperature and 673 K. The mixing of the mar ker layers with the matrix was analyzed by depth profiling using Ruthe rford backscattering spectroscopy (RBS). Additionally, in case of the alumina marker system, to measure the aluminium depth distribution, nu clear reaction analysis (NRA) was applied using the Al-27(p, gamma)Si- 28 reaction with a resonance energy of 992 keV. Film stability was che cked by scanning electron microscopy (SEM).