Activation entropies for diffusion in cubic silicon carbide from first principles

AbstractThe basic properties of palladium impurities in silicon carbide, such as solubility or diffusion mechanisms, are far from being well understood. In a recent paper I presented a systematic study of stability and kinetic properties of Pd in cubic silicon carbide using first principles calculations. In this paper I focus on the effect of the presence of palladium in silicon carbide, even in very low concentrations, on the kinetic properties of carbon vacancies. I apply a odel of Pd diffusion through a vacancy mechanism on the carbon sublattice and extract the correlation factors leading to an enhancement of vacancy migration, due to the coupling of iffusion fluxes between vacancies and palladium impurities.

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First-principles prediction of the negatively-charged nitrogen-silicon-vacancy center in cubic silicon carbide

Journal of Applied Physics ◽

10.1063/1.3471813 ◽

2010 ◽

Vol 108 (4) ◽

pp. 043917 ◽

Cited By ~ 9

Author(s):

Fengchun Pan ◽

Mingwen Zhao ◽

Liangmo Mei

Keyword(s):

Silicon Carbide ◽

First Principles ◽

Silicon Vacancy ◽

Cubic Silicon Carbide ◽

Vacancy Center

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Ab Initio Investigations of Threshold Displacement Energies and Stability of Associated Defects in Cubic Silicon Carbide

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.108-109.671 ◽

2005 ◽

Vol 108-109 ◽

pp. 671-676

Author(s):

Guillaume Lucas ◽

Laurent Pizzagalli

Keyword(s):

Molecular Dynamics ◽

Silicon Carbide ◽

First Principles ◽

Transition State Theory ◽

State Theory ◽

The Stability ◽

Dynamics Simulations ◽

Cubic Silicon Carbide ◽

Threshold Displacement ◽

Good Agreement

Using first principles molecular dynamics simulations, we have recently determined the threshold displacement energies and the associated created defects in cubic silicon carbide. Contrary to previous studies using classical molecular dynamics, we found values close to the experimental consensus, and also created defects in good agreement with recent works on interstitials stability in silicon carbide. We have also investigated the stability of several Frenkel pairs, using transition state theory and constrained path calculations.

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First-Principles Simulations of Frenkel Pair Formation and Annealing in Irradiated ß-SiC

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.131-133.247 ◽

2007 ◽

Vol 131-133 ◽

pp. 247-252

Author(s):

Laurent Pizzagalli ◽

Guillaume Lucas

Keyword(s):

Molecular Dynamics ◽

Silicon Carbide ◽

First Principles ◽

Pair Formation ◽

Atomic Scale ◽

Elastic Band ◽

Treatment Threshold ◽

The Stability ◽

Cubic Silicon Carbide ◽

Threshold Displacement

Using first principles molecular dynamics and Nudged Elastic Band calculations, we have investigated the effect of irradiation on cubic silicon carbide at the atomic scale, and in particular the formation of Frenkel pairs, and the crystal recovery after thermal treatment. Threshold displacement energies have been determined for C and Si sublattice, and the stability and structure of the formed Frenkel pairs are described. The activation energies for annealing these defects have then been computed and compared with experiments.

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