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arXiv · 2401.17341

In situ investigation of growth modes during plasma-assisted molecular beam epitaxy of (0001)GaN

G. Koblmüller·S. Fernández-Garrido·E. Calleja·J. S. Speck
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Abstract

Real-time analysis of the growth modes during homoepitaxial (0001)GaN growth by plasma-assisted molecular beam epitaxy was performed using reflection high energy electron diffraction. A growth mode map was established as a function of Ga/N flux ratio and growth temperature, exhibiting distinct transitions between three-dimensional (3D), layer-by-layer and step-flow growth mode. The layer-by-layer to step-flow growth transition under Ga-rich growth was surfactant mediated and related to a Ga adlayer coverage of one monolayer. Under N-rich conditions the transition from 3D to layer-by-layer growth was predominantly thermally activated, facilitating two-dimensional growth at temperatures of thermal decomposition.

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G. Koblmüller, S. Fernández-Garrido, E. Calleja, J. S. Speck. 2024-01-30. In situ investigation of growth modes during plasma-assisted molecular beam epitaxy of (0001)GaN. https://doi.org/10.1063/1.2789691

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