About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
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| Symposium
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Progress Toward Mechanisms, Thermodynamics, and Kinetics of Phase Transformations: An MPMD/SMD Symposium Honoring John H Perepezko
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| Presentation Title |
Simulating and Visualizing Dislocation Formation Mechanisms on Substrates Containing Pre-Existing Dislocations |
| Author(s) |
John Faiella, Jiaqi Sun, Youping Chen |
| On-Site Speaker (Planned) |
John Faiella |
| Abstract Scope |
Defect control is a critical challenge of manufacturing semiconductor heterostructures, particularly in highly lattice-mismatched systems where high-density dislocations impede device performance. The two major mechanisms of dislocation formation during epitaxy are (1) nucleation of dislocation half-loops from the surface of the growing epilayer, and (2) extension of pre-existing dislocations in the substrate to the epilayer. We have previously demonstrated the first mechanism, i.e., the nucleation of dislocation half-loops from the growth surface on a perfect crystal substrate. This work aims to simulate epitaxial processes on substrates with preexisting dislocations to demonstrate the second mechanism. Concurrent Atomistic-Continuum (CAC) simulations of PbSe/PbTe heteroepitaxial growth have been conducted. Dislocation extension from the substrate into the epilayer has been observed with atomic resolution. These extended dislocation lines contribute to the formation of dislocation networks. We characterize the effects of pre-existing dislocations on the structure, type, and density of the misfit and threading dislocations.
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| Proceedings Inclusion? |
Planned: |
| Keywords |
Thin Films and Interfaces, Other, Modeling and Simulation |