Surface reconstruction and energetics for the growth of GaN
using atomic-N source

Xiaojie Chen, and W. A. Goddard, III

## Abstract

Using the Gaussian Dual Space Density Functional Theory (GDS/DFT), we have
investigated the viability of molecular beam epitaxial (MBE)
growth of GaN using atomic N source.
The c-GaN(100)$_N$ is found to prefer c(2x2) over p(2x1) reconstruction
due to the net charge transfer from second layer Ga to top layer
N atoms.
Energetics relevant to the growth processes are calculated.
It is found that ground state atomic N source leads to favour growth
against surface-N abstraction, while the excited state (doublet)
atomic N source leads to the surface-N abstraction with high probability.
It is suggested that for the growth of good quality GaN, one should
choose the growth condition such as to enhance the Ga mobility under
Ga-rich conditions.