Atomistic modeling of the structure and diffusion processes at Al(110)/Si(001) interphase boundaries obtained by vapor deposition

TL;DR

This study uses molecular dynamics simulations to analyze atomic structure and diffusion at the Al(110)/Si(001) interface, revealing dislocation-induced diffusion pathways and anisotropy resulting from vapor deposition.

Contribution

It provides new insights into the atomic-scale structure and diffusion mechanisms at Al/Si interfaces created by vapor deposition, highlighting the role of misfit dislocations.

Findings

Misfit dislocations form an array at the interface.

Si segregates more strongly to full dislocations.

Diffusion is faster along dislocations, especially full ones.

Abstract

We report on molecular dynamics simulations of the atomic structure and diffusion processes at Al(110)/Si(001) interphase boundary created by simulated vapor deposition of Al(Si) alloy onto Si(001) substrate. An array of parallel misfit dislocations of both full and partial types is observed at the interface. Si atoms segregate to the misfit dislocations, with segregation to full dislocations being stronger. The interface diffusion is dominated by short-circuit diffusion along the misfit dislocations, creating a significant diffusion anisotropy. Diffusion of Al and Si atoms along the full misfit dislocations is faster than along the partial misfit dislocations. Due to the presence of the misfit dislocations, diffusion at the Al(110)/Si(001) interface studied here is faster than diffusion at the Al(111)/Si(111) interfaces investigated in our previous work.