ISSN:
0142-2421
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Physics
Notes:
Thin films of anodically formed Ta2O5 and Nb2O5 on polycristalline Ta and Nb, respectively, are analysed with AES during sputtering with Ar+ ions at energies between 0.5 keV and 5 keV. A sputtering induced depletion of oxygen at the surface is observed in both oxides. The kinetics of this depletion and the steady-state composition at the surface of the samples are studied as a function of the primary ion energy. The results are interpreted using a modification of the model of Ho et al. (1976) for the preferential sputtering of alloys. The thickness of the transient layer increases non-linearly from 1.6 to 3.4 nm with increasing ion energy. Below 2 keV, the surface depletion of oxygen increases with decreasing ion energy and is constant above 2 keV up to 5 keV. The results are similar for both oxides. At 2 keV, the minimum measured width of the oxide/metal interface is 2 nm for Ta2O5/Ta and is about two times larger for Nb2O5/Nb. In both cases it increases with the square root of the ion energy and it is independent on the oxide layer thickness between 10 nm and 150 nm.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/sia.740050507
