Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5396807 | Journal of Electron Spectroscopy and Related Phenomena | 2009 | 5 Pages |
Abstract
A X-ray photoelectron spectroscopy (XPS) depth-profile study of the naturally formed native oxide on polycrystalline Ta sample is probed by observing the core level spectra, valence band spectra and workfunction changes. The present paper addresses the issue of the presence of different Ta suboxides along the depth of the oxide layer. Core level spectra, valence band and workfunction measurements all manifest the transformation of insulating Ta2O5 to metallic Ta with a graded distribution of Ta sub-oxides. Effect of ion-beam irradiation and variation in the synthesis method in determining the profile is discussed. By using different ion-beam energies, it has been shown that the ion-beam induced effects are negligible in the study. Differences in the valence states reported in literature with the present study are attributed to the variations in the growth methods.
Related Topics
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Chemistry
Physical and Theoretical Chemistry
Authors
Manika Khanuja, Himani Sharma, B.R. Mehta, S.M. Shivaprasad,