Growth of Germanium Thin Films on Sapphire Using Molecular Beam Epitaxy

Authors

Emmanuel Wangila, University of Arkansas, FayettevilleFollow
Peter Lytvyn, NAS of UkraineFollow
Hryhorii Stanchu, University of Arkansas, FayettevilleFollow
Calbi Gunder, University of Arkansas, FayettevilleFollow
Fernando Maia de Oliveira, University of Arkansas, FayettevilleFollow
Samir Saha, University of Arkansas, FayettevilleFollow
Subhashis Das, University of Arkansas, FayettevilleFollow
Niroshi Eldose, University of Arkansas, FayettevilleFollow
Chen Li, University of Arkansas, FayettevilleFollow
Mohammad Zamani-Alavijeh, University of Arkansas, FayettevilleFollow
Mourad Benamara, University of Arkansas, FayettevilleFollow
Yuriy I. Mazur, University of Arkansas, FayettevilleFollow
Shui-Qing Yu, University of Arkansas, FayettevilleFollow
Gregory J. Salamo, University of Arkansas, FayettevilleFollow

Document Type

Article

Publication Date

11-2023

Keywords

correlation length; bivariate polar histograms; twinning

Abstract

Germanium films were grown on c-plane sapphire with a 10 nm AlAs buffer layer using molecular beam epitaxy. The effects of Ge film thickness on the surface morphology and crystal structure were investigated using ex situ characterization techniques. The nucleation of Ge proceeds by forming (111) oriented three-dimensional islands with two rotational twin domains about the growth axis. The boundaries between the twin grains are the origin of the 0.2% strain and tilt grains. The transition to a single-grain orientation reduces the strain and results in a better-quality Ge buffer. Understanding the role of thickness on material quality during the Ge(111)/Al₂O₃(0001) epitaxy is vital for achieving device quality when using group IV material on the sapphire platform.

Citation

Wangila, E.; Lytvyn, P.; Stanchu, H.; Gunder, C.; de Oliveira, F.M.; Saha, S.; Das, S.; Eldose, N.; Li, C.; Zamani-Alavijeh, M.; et al. Growth of Germanium Thin Films on Sapphire Using Molecular Beam Epitaxy. Crystals 2023, 13, 1557. https://doi.org/10.3390/cryst13111557

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.