Spontaneous formation of nanostructures by surface spinodal decomposition in GaAs1-xBix epilayers

Luna E, Wu M, Puustinen J, Guina M, Trampert A (2015)

Publication Language: English

Publication Status: Published

Publication Type: Journal article, Original article

Publication year: 2015

Journal

Journal of Applied Physics AIP Publishing

Publisher: American Institute of Physics Inc.

Book Volume: 117

Article Number: 185302

Journal Issue: 18

DOI: 10.1063/1.4919896

Abstract

We report on the spontaneous formation of lateral composition modulations (LCMs) in Ga(As,Bi) epilayers grown by low-temperature (<300 °C) molecular beam epitaxy (MBE) on GaAs(001). Both cross-section and plan-view transmission electron microscopy techniques are used to investigate the nature of the LCMs, consisting of Bi-rich cylinder-like nanostructures lying along the [001] growth direction. The observed LCMs are the consequence of a two-dimensional phase separation process occurring at the surface of the growing epilayers, and their columnar nature is consistent with a surface-directed spinodal decomposition process. Although LCMs are thermodynamically driven, we show how they can be kinetically controlled, in particular, through the As/Ga flux ratio and the substrate temperature. This is a result of LCMs developing from surface atomic diffusion processes, since the atomic dimer configurations on the surface alter adatom diffusivity. The significant role of the surface reconstructions is also discussed.

Authors with CRIS profile

Mingjian Wu Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)

Additional Organisation(s)

Interdisziplinäres Zentrum, Center for Nanoanalysis and Electron Microscopy (CENEM)

Involved external institutions

Tampere University of Technology FI Finland (FI) Paul-Drude-Institut für Festkörperelektronik - Leibniz-Institut im Forschungsverbund Berlin e.V. DE Germany (DE)

How to cite

APA:

Luna, E., Wu, M., Puustinen, J., Guina, M., & Trampert, A. (2015). Spontaneous formation of nanostructures by surface spinodal decomposition in GaAs1-xBix epilayers. Journal of Applied Physics, 117(18). https://dx.doi.org/10.1063/1.4919896

MLA:

Luna, Esperanza, et al. "Spontaneous formation of nanostructures by surface spinodal decomposition in GaAs1-xBix epilayers." Journal of Applied Physics 117.18 (2015).

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