Density Functional Theory (DFT) calculations were used to study the GaN(0001) surface  covered with H adatoms, NH₃ admolecules and NH₂ radicals. This corresponds to physical conditions during GaN growth by hydride vapor phase epitaxy (HVPE), metalorganic vapor phase epitaxy (MOVPE) or ammonothermal methods. In comparison to the earlier work of other authors [1], the reported calculations were based on larger size representation of the surface i.e. the slabs of lateral size 4x4 were routinely used. In addition, the effect of doping type on the stability of the layer covering the surface was examined. The results show that the different doping in the bulk can lead to slightly different surface coverage. For some specific surface coverage the pinning of the Fermi level on surface states and the band bending disappears. In this case the doping of the semiconductor bulk (p-type, semiinsulating or n-type) and the related Fermi level is extremely important in the context of the stability of the surface and the possible adsorption/desorption processes. This phenomenon is observed in a narrow coverage range which entails use a large size of the simulated domain, allowing to control small changes in the surface coverage.

[1] C. G. Van de Walle and J. Neugebauer, Phys. Rev. Lett. 88, 066103 (2002)

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/30285 must be provided.

1. GaN/AlN junctions - density functional study
2. An influence of parallel electric field on the dispersion relation of graphene – a new route to Dirac logics
3. Drift-diffusion simulations of gallium nitride based heterostructures
4. Absorption and emission spectra of InN/GaN superlattice structures by DFT methods
5. Absorption and emission spectra of AlN/GaN superlattice structures by DFT methods
6. Bulk GaAs growth by Contactless Liquid Phase Electroepitaxy
7. Adsorption of ammonia on hydrogen covered GaN(0001) surface – Density Functional Theory (DFT) study
8. Adsorption of gallium on GaN(0001) surface in ammonia rich conditions - Density Functional Theory (DFT) study
9. Density Functional Theory (DFT) study of hydrogen on GaN (0001) surface
10. Surface structure and diffusion of Si and C adatoms on bare SiC(0001) and SiC(0001) surfaces- density functional theory studies
11. First-principles calculations of structural and electronic properties of GaN(0001)/Ga interface
12. A density functional  theory study of the Zn, O, O₂, and H₂O adsorption on the polar ZnO(0001) and ZnO(000-1) surfaces
13. Surface morphology of InGaN layers
14. Modelling of the growth of nitrides in ammonia rich environment
15. Transport properties on nitrogen at high pressure and temperature: viscosity – MD study.
16. Adsorption processes during growth of GaN by HVPE
17. Rietveld refinement for polycrystalline indium nitride
18. Mass flow and reaction analysis of the growth of GaN layers by HVPE