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Models of core reconstruction for the 90-degree partial dislocation in semiconductors

R. W. Nunes·David Vanderbilt
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Abstract

We compare the models that have been proposed in the literature for the atomic structure of the 90-degree partial dislocation in the homopolar semiconductors, silicon, diamond, and germanium. In particular, we examine the traditional single-period and our recently proposed double-period core structures. Ab-initio and tight-binding results on the core energies are discussed, and the geometries are compared in light of the available experimental information about dislocations in these systems. The double-period geometry is found to be the ground-state structure in all three materials. We address boundary-conditions issues that have been recently raised about these results. The structures of point excitations (kinks, solitons, and kink-soliton complexes) in the two geometries are also reviewed.

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R. W. Nunes, David Vanderbilt. 2000-08-08. Models of core reconstruction for the 90-degree partial dislocation in semiconductors. https://doi.org/10.1088/0953-8984%2F12%2F49%2F301

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