Empirical potential approach to the epitaxial relationship between AlN thin films and Si(001) substrates

Abstract

Epitaixial relationship between AlN thin films and Si(001) substrates is systematically investigated using the empirical interatomic potential on the basis of the experimental findings for AlN on Si(001) grown by plasma-assisted molecular beam epitaxy and reactive magnetron sputtering. The calculated results for the structural stability of AlN on Si(001) reveal that (0001)-oriented 2H-AlN becomes stable even on 3C-Si(001) beyond the film thickness of six monolayers with epitaxial relationship of AlN〈01-10〉{norm of matrix}Si[110]. This is consistent with the experimental results found in plasma-assisted molecular beam epitaxy. We also estimate the relative appearance ratio among various rotational domains with AlN〈11-20〉{norm of matrix}Si[110] (Type A) and AlN〈01-10〉{norm of matrix}Si[100] (Type B) in addition to the AlN〈01-10〉{norm of matrix}Si[110] (Type C). The calculated appearance ratio such as 23.7% (Type A), 30.7% (Type B), and 14.8% (Type C) are favourably compared with respective experimental results such as 24.7%, 26.5%, and 22.8% obtained by reactive magnetron sputtering. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.