Low Energy Ion Scattering (LEIS) is a technique with ultimate sensitivity to only topmost atomic layer. We applied it together with XPS to studying the interaction of La and B layers at interfaces, which is crucial for improvement of properties of La/B-based multilayer mirrors for 6.7 nm wavelength light. Unusual drop of LEIS signal on La surface was observed, especially pronounced when interaction with O or B takes place. This behavior was found to be a rare matrix effect caused by low work functions of pure La as well as its compounds, which results in dominance of a resonant charge transfer mechanism, affecting LEIS signal. Since only La is present in the spectrum, matrix effect is formed by the sub-surface O and B atoms. Plotting normalized LEIS signal versus inversed velocity of the incident ions makes quantification of the surface composition possible.
|Publication status||Published - 19 Jan 2016|
|Event||Physics@FOM Veldhoven 2016 - NH Koningshof Veldhoven, Veldhoven, The Netherlands, Netherlands|
Duration: 20 Jan 2016 → 20 Jan 2016
|Conference||Physics@FOM Veldhoven 2016|
|City||Veldhoven, The Netherlands|
|Period||20/01/16 → 20/01/16|