The analysis of the characteristic losses's nature occurrence of electron energy on a surface of metals Cu and Pd

 

М.А.Vasylyev1, V.A Tinkov1(*), A.A.Tinkova1,2

 

1 G. V. Kurdyumov Institute for Metal Physics, National Academy of Sciences of Ukraine, Kiev, Ukraine

1,2 National Technical University of Ukraine «KPI», Kiev, Ukraine

*E-mail: sheyh@imp.kiev.ua

The nature of occurrence of electron’s energy  characteristic losses in secondary electron’s issue spectra from surfaces of metals Cu, Pd and alloy Cu75Pd25 (100) in a low-energy range of energy of primary electrons Е0 was investigated. The basic types of losses are revealed: superficial and volumetric plasmotrons and their hybrid mode, interband transition and ionization losses. It was revealed, that for Cu, Pd and alloy Cu75Pd25 (100) experimental values of plasmotron’s energy are localized at smaller energies, than the theory of free electronic gas predicts. It is established, that presence of dispersion at plasma fluctuations is caused by complex electronic structure and heterogeneity of electronic condition's density in near-surface layer.

Not destroying level-by-level analysis of alloy Cu75Pd25 (100) with application of ionization spectroscopy which allows to define dependence of concentration of elements on depth of sounding by primary electrons [1] was lead. It is established, that ordered alloy Cu75Pd25 (100) has oscillating on depth a concentration profile. The structure of odd nuclear layers is close to 50 % Cu on 50 % Pd, and even layers consist from pure Cu. The method of diffraction of slow electrons on a surface of an alloy had been found out a superstructural lattice with (2х2).

In the presented work for alloy Cu75Pd25 (100) correlation between change and attenuation of intensity of superficial and volumetric plasmotron’s lines with results of not destroying level-by-level analysis of alloy's surface structure has been found out. It is established, that under the attitude of intensityes lines of superficial and volumetric R plasmones depending on energies Е0 for alloy Cu75Pd25 (100) it is possible to define boundary surface-volume [2].

[1]   M.A. Vasylyev, V.A. Tinkov et al., Appl. Surf. Sci. 253: 1081 (2006).

[2]   M.A. Vasylyev, V.A. Tinkov et al., J. Electron. Spectrosc. Rel. Phenom., 159: 53 (2007).