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The paper presents a multiscale study of the kinetic processes of the heteroepitaxial growth of the PbSe/PbTe (111) and PbTe/PbSe(001) systems, using the Concurrent Atomistic-Continuum (CAC) method as the simulation tool. The CAC simulations have reproduced the Stranski–Krastanov growth mode and the layer-by-layer growth mode of the two systems, respectively; the pyramid-shaped island morphology of the PbSe epilayer on PbTe (111), the square-like misfit dislocation networks within the PbTe/PbSe(001) interface, and the critical thickness for the PbTe/PbSe(001) system at which coherent interfaces transit to semi-coherent interfaces with the formation of misfit dislocations, all in good agreement with experimental observations. Four types of misfit dislocations are found to form during the growth of the two PbTe/PbSe heterosystems, and hexagonal-like misfit dislocation networks are observed within the PbSe/PbTe(111) interfaces. The growth processes, including the formation of misfit dislocations, have been visualized. Dislocation half-loops have been observed to nucleate from the epilayer surfaces. These half-loops extend towards the interface by climb or glide motions, interact with other half-loops, and form misfit dislocation networks at the interfaces and threading dislocations extending from interfaces to epilayer surfaces. The dominant types of misfit dislocations in both systems are found to be those with Burgers vectors parallel to the interfaces, whereas the misfit dislocations with Burgers vectors inclined to the interface have a low likelihood of generation and tend to annihilate. The size of the substrate is demonstrated to have a significant effect on the formation, evolution, and distribution of dislocations on the growth of PbSe on PbTe(111).
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Si/Ge (111) Semicoherent Interfaces: Responses to an In‐Plane Shear and Interactions with Lattice Dislocations
Concurrent atomistic–continuum simulations are employed to study Si/Ge (111) semicoherent interfaces in terms of their responses to an in‐plane shear and interactions with lattice dislocations. Three types of Si/Ge interfaces, differing in interfacial structures and energy, are considered. Type I interface coincides with the shuffle‐set slip plane and contains a hexagonal network of edge dislocations. Type II and Type III interfaces both coincide with the glide‐set slip plane, yet they contain, respectively, a triangular and a hexagonal network of Shockley partial dislocations. The simulations show that among the three types of interfaces, 1) Type I interface is the least stable subject to an in‐plane shear and 2) Type III interface impedes the gliding of lattice dislocations the most significantly.
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- Award ID(s):
- 1761512
- PAR ID:
- 10239133
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- physica status solidi (b)
- Volume:
- 257
- Issue:
- 12
- ISSN:
- 0370-1972
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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