Monte Carlo simulations of growth modes of Pb nanoislands on Si(111) surface
Institute of Physics, AS CR, v.v.i., Na Slovance 2, 182 21 Prague 8, Czech Republic
2 Ames Laboratory - USDOE, Iowa State University, Ames, Iowa, 50011, USA
Revised: 25 March 2008
Published online: 16 July 2008
The growth of Pb islands on a Si(111) surface exhibits many interesting properties. For example, the self-assembled process results in a homogeneous distribution of Pb islands with uniform height. The dependence of this height on coverage and temperature can be expressed as a phase diagram [M. Hupalo et al., Surf. Sci. 493, 526 (2001)]. In this paper we develop a model of the growth process that reflects the main features of the experimental observations and determines the key processes of quantum dot formation in a Pb/Si(111) system. The growth of islands is simulated by the Monte Carlo method. With suitably chosen parameters the model is able to reconstruct the phase diagram, via the dependence of the dynamics of Pb atoms on area and height. These dependencies are attributed to stress energy and quantum size effects.
PACS: 68.55.-a – Thin film structure and morphology / 68.65Hb – Quantum dots (patterned in quantum wells / 81.16Dn – Self-assembly
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2008