Abstract
Non-polar a-plane GaN layers were grown on planar and hemispherical micro- and nano-patterned r-sapphire substrates (PSS) by metal organic chemical vapor deposition (MOCVD). Double Crystal X-ray Rocking Curve (DCXRC) and Transmission Electron Microscopy (TEM) analyses showed that the crystal quality of a-GaN grown on the micro-PSS was the best among three kinds of r-sapphire substrates, which was attributed to defect reduction through lateral overgrowth on the hemispherical patterns. The intensity of the near band-edge emission (NBE) at 3.4eV from a-GaN on the micro-PSS was increased by about 30 times compared with that of the conventional a-plane GaN on planar r-sapphire, while the yellow emission spectrum at 2.2eV was the lowest among the three samples. Comparison of the micro-photoluminescence mapping image and the cross-section TEM also showed high and low defect regions on the planar section and hemisphere, respectively.
Original language | English |
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Pages (from-to) | S90-S94 |
Journal | Current Applied Physics |
Volume | 11 |
Issue number | 4 SUPPL. |
DOIs | |
Publication status | Published - 2011 Jul |
Bibliographical note
Funding Information:This work was supported by the Strategic Technology Development Project No. 10031885 and the IT R&D Program Project No. 2009-F-022-01 of the Ministry of Knowledge Economy .
Copyright:
Copyright 2011 Elsevier B.V., All rights reserved.
Keywords
- Defect reduction
- InGaN
- Non-polar GaN
- PSS
ASJC Scopus subject areas
- General Materials Science
- General Physics and Astronomy