Coverage dependence of the structure of Si deposited layers on a Si(001) surface investigated by reflection electron microscopy

The structure of Si layers deposited on a Si(001) 2x1 surface at room temperature is investigated by reflection electron microscopy. After the sample heating by direct current, the structure of the deposited layer returns to the 2x1 surface at coverages below I monolayer (ML), but changes to a rough surface with the 2x1 and the 1x2 domains at coverages above 1 ML. Since the vacancies exist in the deposited layer at coverages below 1 ML, these vacancies will accelerate the recovery process of the 2 x 1 surface by enhancing adsorbate migration. (C) 1999 Elsevier Science B.V. All rights reserved.