Ab initio density functional theory study on the atomic and electronic structure of GaP/Si(001) heterointerfaces

Author(s)
O. Romanyuk, O. Supplie, T. Susi, M. M. May, T. Hannappel
Abstract

The atomic and electronic band structures of GaP/Si(001) heterointerfaces were investigated by ab initio density functional theory calculations. Relative total energies of abrupt interfaces and mixed interfaces with Si substitutional sites within a few GaP layers were derived. It was found that Si diffusion into GaP layers above the first interface layer is energetically unfavorable. An interface with Si/Ga substitution sites in the first layer above the Si substrate is energetically the most stable one in thermodynamic equilibrium. The electronic band structure of the epitaxial GaP/Si(001) heterostructure terminated by the (2 x 2) surface reconstruction consists of surface and interface electronic states in the common band gap of two semiconductors. The dispersion of the states is anisotropic and differs for the abrupt Si-Ga, Si-P, and mixed interfaces. Ga 2p, P 2p, and Si 2p core-level binding-energy shifts were computed for the abrupt and the lowest-energy heterointerface structures. Negative and positive core-level shifts due to heterovalent bonds at the interface are predicted for the abrupt Si-Ga and Si-P interfaces, respectively. The distinct features in the heterointerface electronic structure and in the core-level shifts open new perspectives in the experimental characterization of buried polar-on-nonpolar semiconductor heterointerfaces.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
Czech Academy of Sciences, Technische Universität Ilmenau, University of Cambridge
Journal
Physical Review B
Volume
94
No. of pages
9
ISSN
1098-0121
DOI
https://doi.org/10.1103/PhysRevB.94.155309
Publication date
10-2016
Peer reviewed
Yes
Austrian Fields of Science 2012
103018 Materials physics
Keywords
Portal url
https://ucris.univie.ac.at/portal/en/publications/ab-initio-density-functional-theory-study-on-the-atomic-and-electronic-structure-of-gapsi001-heterointerfaces(0d76924d-2f60-4678-a3f9-20b3aa241815).html