Adatom Diffusion at GaN (0001) and (000bar1) Surfaces

T. Zywietz; J. Neugebauer; M. Scheffler

doi:10.1063/1.121909

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Adatom Diffusion at GaN (0001) and (000bar1) Surfaces

T. Zywietz·J. Neugebauer·M. Scheffler

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Abstract

The diffusion of Ga and N adatoms has been studied for the technologically relevant wurtzite (000bar1) and (0001) surfaces employing density-functional theory. Our calculations reveal a very different diffusivity for Ga and N adatoms on the equilibrium surfaces: While Ga is very mobile at typical growth temperatures, the diffusion of N is by orders of magnitudes slower. These results give a very detailed insight of how and under which growth conditions N adatoms can be stabilized and efficiently incorporated at the surface. We further find that the presence of excess N strongly increases the Ga diffusion barrier and discuss the consequences for the growth of GaN.

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T. Zywietz, J. Neugebauer, M. Scheffler. 1998-09-01. Adatom Diffusion at GaN (0001) and (000bar1) Surfaces. https://doi.org/10.1063/1.121909

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