Surfactant induced reversible changes of surface morphology
In: Physical Review Letters, Jg. 71 (1993) ; Nr. 19, S. 3170-3173
ISSN: 0031-9007, 1079-7114
Zeitschriftenaufsatz / Fach: Physik
Fakultät für Physik » Experimentalphysik
We have investigated the influence of a surfactant on the equilibrium surface morphology in the pseudomorphic regime of heteroepitaxial growth. At 700 °C, 8 monolayers of Ge on Si(001) using Sb as surfactant form strained islands with a size of ∼300 Å, allowing partial elastic relaxation. The surface morphology depends strongly on the Sb coverage and changes from islands with  facets at high Sb coverage via round, flat cones with an inclination angle of 12° to islands rotated by 45° with  facets formed during growth at low Sb coverage. The equilibrium conditions are verified by the reversible transition from  facets to 12° cones initiated by a change of the surfactant coverage.