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Nucleation and Growth of GaN/AlN Quantum Dots

C. Adelmann·B. Daudin·R. A. Oliver·G. A. D. Briggs·R. E. Rudd
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Abstract

We study the nucleation of GaN islands grown by plasma-assisted molecular-beam epitaxy on AlN(0001) in a Stranski-Krastanov mode. In particular, we assess the variation of their height and density as a function of GaN coverage. We show that the GaN growth passes four stages: initially, the growth is layer-by-layer; subsequently, two-dimensional precursor islands form, which transform into genuine three-dimensional islands. During the latter stage, island height and density increase with GaN coverage until the density saturates. During further GaN growth, the density remains constant and a bimodal height distribution appears. The variation of island height and density as a function of substrate temperature is discussed in the framework of an equilibrium model for Stranski-Krastanov growth.

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C. Adelmann, B. Daudin, R. A. Oliver, G. A. D. Briggs, R. E. Rudd. 2003-11-03. Nucleation and Growth of GaN/AlN Quantum Dots. https://doi.org/10.1103/physrevb.70.125427

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