Relative stability of extended interstitial defects in silicon: First-principles calculations

Abstract

Interstitials stored in ͕311͖ or ͕111͖ habit planes form rows of interstitial chains elongated in ͗011͘ direction. Exploiting the large aspect ratio to treat chains as infinite, first-principles calculations of large computation supercells reveal a unique formation energy trend for each defect, which is closely correlated with its distinct shape. The most energetically favorable structure changes from ͕311͖ rodlike defects to Frank loops as the number of interstitials in the defect increases. These results are consistent with transmission electron microscopy studies.

Ideas in Chemistry and Molecular Sciences: Where Chemistry Meets Life. Edited by Bruno Pignataro.

“…The results presented here, are thus an important finding that a classical potential can be specially fitted to reproduce geometric ground states and local minima faithfully for a useful subset of defects (with a quality similar to TB), even though saddle points and details of the energy landscape are still not correct. Furthermore, the reparametrized MEAM model has been used in large scale MD simulations 36, 37 further validating its utility in studying defective silicon.…”

Modeling of defects, dopant diffusion and clustering in silicon

“…Under certain conditions, particularly for high-dose implants, {113} defects can transform into into dislocation loops, perfect (PDLs) and faulted (FDLs) [106]. This transformation has been proposed to be due to some unfaulting reactions, as it has been shown recently by using ab initio simulation techniques [107]. The formation energy of FDLs tends to 0.027 eV with increasing size, while it tends to 0 for PDLs [105].…”

A topological point defect regulates the evolution of extended defects in irradiated silicon

“…20,12,21 The calculated formation energy hierarchy among three types of extended defects indicates that the formation of the ͕311͖ defect is initially favored during the annealing of an irradiated sample. 20,12,21 The calculated formation energy hierarchy among three types of extended defects indicates that the formation of the ͕311͖ defect is initially favored during the annealing of an irradiated sample.…”