Horn-von Hoegen, Michael; Al Falou, A.; Müller, B.H.; Köhler, U.; Andersohn, L.; Dahlheimer, B.; Henzler, M.:

Surfactant-stabilized strained Ge cones on Si(100)

In: Physical Review B, Jg. 49 (1994) ; Nr. 4, S. 2637-2650
ISSN: 1098-0121, 1550-235X
Zeitschriftenaufsatz / Fach: Physik
Fakultät für Physik » Experimentalphysik
The formation of circular cone-shaped Ge islands (12° cones) has been observed for the growth of eight monolayers of Ge on Si(001) at 700 °C using Sb as a surfactant. The Ge cones are strained and grow pseudomorphically, adopting the Si lattice constant. They have a tilt angle of 12° and are composed of [117]-, [105]-type, and all intermediate facets. The island-size distribution is peaked around a typical size of ∼300–400 Å, which results from a formation process under equilibrium conditions for diffusion of the Ge atoms. Growth at lower temperatures down to 300 °C with Sb as a surfactant results in epitaxial but very rough Ge films which show a high degree of disorder.