Diffusion of hydrogen in crystalline silicon

TL;DR

This study uses tight-binding molecular dynamics to calculate hydrogen diffusion in crystalline silicon, showing that long jumps dominate at high temperatures and that classical Arrhenius parameters can be extrapolated to low temperatures.

Contribution

It provides a detailed computational analysis of hydrogen diffusion in silicon, confirming previous results and clarifying the temperature dependence of diffusion mechanisms.

Findings

Long jumps dominate at high temperatures

No abrupt change in diffusion coefficient with decreasing temperature

Arrhenius parameters extrapolate to low temperatures

Abstract

The coefficient of diffusion of hydrogen in crystalline silicon is calculated using tight-binding molecular dynamics. Our results are in good quantitative agreement with an earlier study by Panzarini and Colombo [Phys. Rev. Lett. 73, 1636 (1994)]. However, while our calculations indicate that long jumps dominate over single hops at high temperatures, no abrupt change in the diffusion coefficient can be observed with decreasing temperature. The (classical) Arrhenius diffusion parameters, as a consequence, should extrapolate to low temperatures.