| Full text | |
| Author(s): |
Trushin, O.
[1]
;
Maras, E.
[2, 3]
;
Stukowski, A.
[4]
;
Granato, E.
[5, 6]
;
Ying, S. C.
[6]
;
Jonsson, H.
[2, 7]
;
Ala-Nissila, T.
[2, 3, 6]
Total Authors: 7
|
| Affiliation: | [1] Russian Acad Sci, Yaroslavl Branch, Inst Phys & Technol, Yaroslavl 150007 - Russia
[2] Aalto Univ, Sch Sci, Dept Appl Phys, FIN-00076 Espoo - Finland
[3] Aalto Univ, Sch Sci, COMP Ctr Excellence, FIN-00076 Espoo - Finland
[4] Tech Univ Darmstadt, Inst Mat Wissensch, D-64287 Darmstadt - Germany
[5] Inst Natl Pesquisas Espaciais, Lab Associado Sensores & Mat, BR-12227010 Sao Jose Dos Campos, SP - Brazil
[6] Brown Univ, Dept Phys, Box 1843, Providence, RI 02912 - USA
[7] Univ Iceland, Fac Phys Sci, IS-107 Reykjavik - Iceland
Total Affiliations: 7
|
| Document type: | Journal article |
| Source: | MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING; v. 24, n. 3 MAR 2016. |
| Web of Science Citations: | 1 |
| Abstract | |
A possible mechanism for the formation of a 90 degrees misfit dislocation at the Ge/Si(0 0 1) interface through homogeneous nucleation is identified from atomic scale calculations where a minimum energy path connecting the coherent epitaxial state and a final state with a 90 degrees misfit dislocation is found using the nudged elastic band method. The initial path is generated using a repulsive bias activation procedure in a model system including 75 000 atoms. The energy along the path exhibits two maxima in the energy. The first maximum occurs as a 60 degrees dislocation nucleates. The intermediate minimum corresponds to an extended 60 degrees dislocation. The subsequent energy maximum occurs as a second 60 degrees dislocation nucleates in a complementary, mirror glide plane, simultaneously starting from the surface and from the first 60 degrees dislocation. The activation energy of the nucleation of the second dislocation is 30% lower than that of the first one showing that the formation of the second 60 degrees dislocation is aided by the presence of the first one. The simulations represent a step towards unraveling the formation mechanism of 90 degrees dislocations, an important issue in the design of growth procedures for strain released Ge overlayers on Si(1 0 0) surfaces, and more generally illustrate an approach that can be used to gain insight into the mechanism of complex nucleation paths of extended defects in solids. (AU) | |
| FAPESP's process: | 14/15372-3 - Dynamics and topological defects in periodic media |
| Grantee: | Enzo Granato |
| Support Opportunities: | Regular Research Grants |