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

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.

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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://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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