Equilibrium shape and size of supported heteroepitaxial nanoislands

Autor(es)

Jalkanen, J. ^[1] ; Trushin, O. ^[2] ; Granato, E. ^{[3, 4]} ; Ying, S. C. ^[3] ; Ala-Nissila, T. ^{[1, 3]}

Afiliação do(s) autor(es)

^[1] Helsinki Univ Technol, Dept Engn Phys, FIN-02015 Espoo - Finland

^[2] Russian Acad Sci, Yaroslavl Branch, Inst Phys & Technol, Yaroslavl 150007 - Russia

^[3] Brown Univ, Dept Phys, Providence, RI 02912 - USA

^[4] Inst Nacl Pesquisas Espaciais, Lab Assoc Sensores & Mat, BR-12245970 Sao Jose Dos Campos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: European Physical Journal B; v. 66, n. 2, p. 175-183, NOV 2008.
• Citações Web of Science: 1

Resumo

We study the equilibrium shape, shape transitions and optimal size of strained heteroepitaxial nanoislands with a two-dimensional atomistic model using simply adjustable interatomic pair potentials. We map out the global phase diagram as a function of substrate-adsorbate misfit and interaction. This phase diagram reveals all the phases corresponding to different well-known growth modes. In particular, for large enough misfits and attractive substrate there is a Stranski-Krastanow regime, where nano-sized islands grow on top of wetting films. We analyze the various terms contributing to the total island energy in detail, and show how the competition between them leads to the optimal shape and size of the islands. Finally, we also develop an analytic interpolation formula for the various contributions to the total energy of strained nanoislands. (AU)

• Processo FAPESP: 07/08492-9 - Dinâmica, defeitos topológicos e transições de fase em meios ordenados
• Beneficiário: Enzo Granato
• Linha de fomento: Auxílio à Pesquisa - Temático