Abstract
In this paper, we report on the improved crystal quality and surface morphology of nonpolar aplane ([11-20]) GaN layers grown on γ-plane ([1-102]) sapphire substrates by using a metal-organic chemical vapor deposition. Both the reactor pressure and the V/III ratio were modulated using twosteps during the growth in order to optimize the growth conditions for the fully coalesced GaN layers with smooth surfaces. As a result, a root-mean-square roughness of 0.678 nm was observed with atomic-force microscopy for the nonpolar α-plane GaN, and the full-widths at half-maximum values of the omega-rocking curve were 432 and 648 arcsec from the c- and the m-direction parallel scans, respectively. The low-temperature photoluminescence spectra were also investigated to identify the origin of the improvement in the crystallinity.
Original language | English |
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Pages (from-to) | 873-877 |
Number of pages | 5 |
Journal | Journal of the Korean Physical Society |
Volume | 58 |
Issue number | 41 |
DOIs | |
Publication status | Published - 2011 Apr 4 |
Keywords
- Crystallinity
- GaN
- MOCVD
- Nonpolar
- Surface morphology
ASJC Scopus subject areas
- Physics and Astronomy(all)