NiO layers of different thickness have been epitaxially grown on a MgO(1 1
0) substrate at various temperatures in the range 700-900 degreesC. Investi
gations by reflection high energy electron diffraction, atomic force micros
copy (AFM) and high resolution transmission electron microscopy (HRTEM) giv
e evidence for a roof-like morphology of the NiO(l 1 0) surface consisting
in (1 0 0) and (0 1 0) facets elongated along the [0 0 1] direction. The pe
riod and height of these facets depend on the layer thickness and the depos
ition temperature. This particular surface configuration is due to a minimi
zation of the surface energy during the growth process. (C) 2001 Elsevier S
cience B.V. All rights reserved.