Surface segregation at the binary alloy CuAu (100) studied by low-energy ion scattering

SURFACE SCIENCE

卷:643

Article

Beilder, Robert¹  Taglauer, Edmund¹ 

[1] Max Planck Inst Plasma Phys, D-85748 Garching, Germany

关键词: Alloys;    CuAu;    Segregation;    Ion scattering;    LEIS;    Numerical simulation;   

DOI  :  10.1016/j.susc.2015.08.030

来源: Elsevier

【 摘 要 】

We present results from an experimental study of segregation at the CuAu (100) surface. It is shown that Au enrichment in the top surface layer persists up to temperatures far beyond the bulk order-disorder transition temperature. From the gradual desegregation at higher temperatures a segregation energy of -0.30 eV was determined. Our results are in quantitative agreement with calculations by Tersoff predicting oscillatory concentration depth profiles with decreasing amplitudes at higher temperatures. For the layer selective surface analysis we used low-energy He+ and Na+ scattering. Data interpretation and quantification were supported by numerical simulations with the MARLOWE code to which we had added the special features of trajectory resolved analysis and anisotropic thermal vibrations of surface atoms. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

Free