Abstract
The morphology of the nanostructured Au(111) surface has been investigated in the temperature range between 170 and by means of thermal energy He atom scattering. The gold surface has been irradiated with ions along the azimuthal direction ⟨110⟩ at grazing incidence (about 75°). After sputtering at temperatures greater than , a well-defined diffraction pattern has been measured, which is consistent with the development of a ripple structure with ridges oriented along the incoming ion-beam direction. The evolution with time of the diffraction pattern has been followed at different crystal temperatures in the range . The results show that the rippled structure is stable up to . Instead, between 370 and , the structure changes with time with a rate that depends on temperature, and the ripple wavelength is constant. The decay is well described by an exponential function, and the estimated activation energy is about . At , the data show an increase of the ripple wavelength and this suggests that shorter wavelength modes, which contribute to the ripple profile, decay faster than longer ones with a shift toward greater values of the average ripple wavelength.
- Received 9 February 2007
DOI:https://doi.org/10.1103/PhysRevB.76.033411
©2007 American Physical Society