Smoothing of nanoscale surface ripples studied by He atom scattering
Smoothing of nanoscale surface ripples studied by He atom scattering
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DOI：
10.1103/physrevb.68.115431
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发表时间：
2003-09
影响因子：
3.7
通讯作者：
L. Pedemonte;G. Bracco;C. Boragno;F. Mongeot;U. Valbusa
中科院分区：
文献类型：
--
作者：
L. Pedemonte;G. Bracco;C. Boragno;F. Mongeot;U. Valbusa
Thermal energy He atom scattering is used to investigate the recovery of a nanometer-scale corrugation on the (110) surface of silver. Periodic and remarkably well-ordered rippled structures with ridges oriented along the $〈001〉$ and $〈11\ifmmode\bar\else\textasciimacron\fi{}0〉$ azimuthal directions are grown by ion sputtering at grazing incidence and at a crystal temperature of 210 K. Hence, morphological equilibration of the corrugated surface is investigated in real time in the temperature range between 200 and 230 K. The activation energy for the mechanism driving surface relaxation of $〈001〉,$ and $〈11\ifmmode\bar\else\textasciimacron\fi{}0〉\ensuremath{-}\mathrm{o}\mathrm{r}\mathrm{i}\mathrm{e}\mathrm{n}\mathrm{t}\mathrm{e}\mathrm{d}$ ripples is measured to be $(0.52\ifmmode\pm\else\textpm\fi{}0.09)$ and $(0.43\ifmmode\pm\else\textpm\fi{}0.05)\mathrm{eV},$ respectively. The same underlying rate limiting process\char22{}i.e., adatom detachment from the open $〈001〉$ step edge\char22{}is suggested. Finally, the ripple amplitude is observed to decay with time following the inverse linear behavior, independently of the ripple orientation and of the substrate temperature. This result disagrees with the predictions of the one-dimensional model by Israeli and Kandel where an exponential decay law is obtained for the case of attachment-detachment limited kinetics.
Thermal energy He atom scattering is used to investigate the recovery of a nanometer-scale corrugation on the (110) surface of silver. Periodic and remarkably well-ordered rippled structures with ridges oriented along the $〈001〉$ and $〈11\ifmmode\bar\else\textasciimacron\fi{}0〉$ azimuthal directions are grown by ion sputtering at grazing incidence and at a crystal temperature of 210 K. Hence, morphological equilibration of the corrugated surface is investigated in real time in the temperature range between 200 and 230 K. The activation energy for the mechanism driving surface relaxation of $〈001〉,$ and $〈11\ifmmode\bar\else\textasciimacron\fi{}0〉\ensuremath{-}\mathrm{o}\mathrm{r}\mathrm{i}\mathrm{e}\mathrm{n}\mathrm{t}\mathrm{e}\mathrm{d}$ ripples is measured to be $(0.52\ifmmode\pm\else\textpm\fi{}0.09)$ and $(0.43\ifmmode\pm\else\textpm\fi{}0.05)\mathrm{eV},$ respectively. The same underlying rate limiting process\char22{}i.e., adatom detachment from the open $〈001〉$ step edge\char22{}is suggested. Finally, the ripple amplitude is observed to decay with time following the inverse linear behavior, independently of the ripple orientation and of the substrate temperature. This result disagrees with the predictions of the one-dimensional model by Israeli and Kandel where an exponential decay law is obtained for the case of attachment-detachment limited kinetics.