Roughening and islanding of monolayer Ce coverage on vicinal Si(001) s
urface has been studied using scanning tunneling microscope (STM). For
a 3.9 degrees miscut surface, planar buckled-dimer surface is a metas
table state limited by a barrier, which can be overcome by a 680 degre
es C annealing. After the annealing, the metastable flat surface has b
een changed to a rough surface of small hills because of step-bunching
, and on top of each hill, a 3 dimensional (3D) nanoscale island was o
bserved. The mechanism of this roughening and islanding process have b
een discussed. (C) 1998 Elsevier Science B.V.