Issue |
Eur. Phys. J. Appl. Phys.
Volume 37, Number 1, January 2007
|
|
---|---|---|
Page(s) | 33 - 37 | |
Section | Surfaces, Interfaces and Films | |
DOI | https://doi.org/10.1051/epjap:2006134 | |
Published online | 22 November 2006 |
https://doi.org/10.1051/epjap:2006134
Equilibrium shapes of coherent islands in heteroepitaxial systems
1
College of Mechanical and Electrical Engineering, Zhejiang University
of Technology, Hangzhou 310032, China
2
Department of Mechanical Engineering, West Branch of Zhejiang
University of Technology, Quzhou 324000, China
3
College of Science, Zhejiang University of Technology, Hangzhou
310032, China
4
Department of Physics, Tsinghua University, Beijing 100084, China
Corresponding author: wangminzhou@sohu.com
Received:
21
May
2006
Accepted:
6
September
2006
Published online:
22
November
2006
An analytical expression of the free energy consisting of the strain energy, surface energy and interfacial energy for the coherent island/substrate system, as well as the evolving relations of aspect ratio against volume of the island and misfit of the system, which provides a broad perspective on island behavior, is obtained, and used to study the equilibrium shapes of the systems. Under certain growth conditions in systems with a film/substrate lattice misfit, deposed material is known to aggregate into islandlike shapes with geometries having triangular shaped cross-sections. A two-dimensional model assuming liner elastic behavior is used to analyze an isolated triangular shaped island with elastic properties similar to those of the substrate assumed to be semi-infinite. The results show that in order to minimize the total free energy, a coherent island will adopt a particular height-to-width aspect ratio that is a function of only the island volume. The effect of a misfit dislocation on the equilibrium shape of an island is in passing examined. These can serve as a basis for interpretation of experiments.
PACS: 68.55.Jk – Structure and morphology; thickness; crystalline orientation and texture / 62.25.+g – Mechanical properties of nanoscale materials / 68.35.-p – Solid surfaces and solid-solid interfaces: Structure and energetics / 68.65.Hb – Quantum dots
© EDP Sciences, 2006
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.