Photoluminescence (PL) bands in GaN associated with point defects involving nitrogen or gallium vacancy (VNor VGa) are reviewed. The VN‐containing defects, including the isolated VNand its complexes with acceptors, are often observed in PL from semi‐insulating GaN and are responsible for the green (GL2) and red (the RL2 family) bands. The complexes of the VGawith hydrogen and oxygen are abundantly formed in n‐type GaN grown by the ammonothermal method. Some of these complexes are responsible for PL bands in the red‐yellow region of the PL spectrum.
Tracking of Point Defects in the Full Compositional Range of AlGaN via Photoluminescence Spectroscopy
A comprehensive energy map as a function of AlGaN composition over the whole alloy range is presented for commonly observed point defects in nominally intrinsic, n‐, and p‐doped material. The map covers intentional and unintentional impurities (CN, MgIII), vacancies (VIII, VN), passivating complexes (H), and self‐compensating complexes. The tracking of these defects is crucial to understand their impact on optical and electrical properties as well as for their mitigation.
- NSF-PAR ID:
- 10408180
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- physica status solidi (a)
- Volume:
- 220
- Issue:
- 8
- ISSN:
- 1862-6300
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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