Critical epitaxial film thickness for forming interface dislocations
Journal
Materials Science and Engineering A
Journal Volume
309-310
Pages
473-477
Date Issued
2001
Author(s)
Abstract
The system of an epitaxial film on a semi-infinite substrate of a different material is considered and the critical thickness of the film to form misfit interface dislocation is derived in the present study. The energy approach is used to predict the critical thickness and both the self-energy of the dislocation and the interaction energy between the dislocation and the mismatch strain are analyzed. The elastic stress field due to the interface dislocation is required in analyzing the energies and both the superposition principle and Fourier integral are adopted to derive this elastic stress field. The predicted stress field in the system satisfy both the free surface condition at the film surface and the continuity condition at the interface. The predicted critical film thickness for forming interface dislocation decreases with the increase in the shear modulus ratio of the film to the substrate. ? 2001 Elsevier Science B.V. All rights reserved.
Subjects
Critical thickness
Dislocation
Epitaxial film
Modeling
Type
journal article