Vacancy clustering and diffusion in silicon: Kinetic lattice Monte Carlo simulations

TL;DR

This study uses Kinetic Lattice Monte Carlo simulations to analyze how vacancies in silicon diffuse and cluster under various temperatures and concentrations, revealing temperature-dependent cluster growth and diffusivity behaviors.

Contribution

It introduces detailed simulation insights into vacancy clustering and diffusion in silicon, highlighting the effects of temperature, concentration, and interaction range on these processes.

Findings

Higher temperatures lead to larger, shorter-lived clusters.

Longer interaction ranges increase diffusivity and reduce cluster numbers.

Vacancy diffusivity follows a power law with an exponent affected by temperature and concentration.

Abstract

Diffusion and clustering of lattice vacancies in silicon as a function of temperature, concentration, and interaction range are investigated by Kinetic Lattice Monte Carlo simulations. It is found that higher temperatures lead to larger clusters with shorter lifetimes on average, which grow by attracting free vacancies, while clusters at lower temperatures grow by aggregation of smaller clusters. Long interaction ranges produce enhanced diffusivity and fewer clusters. Greater vacancy concentrations lead to more clusters, with fewer free vacancies, but the size of the clusters is largely independent of concentration. Vacancy diffusivity is shown to obey power law behavior over time, and the exponent of this law is shown to increase with concentration, at fixed temperature, and decrease with temperature, at fixed concentration.