کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1678053 | 1009926 | 2010 | 7 صفحه PDF | دانلود رایگان |
Although the theory of high-angle elastic scattering of fast electrons is well developed, accurate calculation of the incident-energy threshold and cross section for surface-atom sputtering is hampered by uncertainties in the value of the surface-displacement energy Ed and its angular dependence. We show that reasonable agreement with experiment is achieved by assuming a non-spherical escape potential with Ed=(5/3) Esub, where Esub is the sublimation energy. Since field-emission sources and aberration-corrected TEM lenses have become more widespread, sputtering has begun to impose a practical limit to the spatial resolution of microanalysis for some specimens. Sputtering can be delayed by coating the specimen with a thin layer of carbon, or prevented by reducing the incident energy; 60 keV should be sufficiently low for most materials.
Journal: Ultramicroscopy - Volume 110, Issue 8, July 2010, Pages 991–997