Polar and semipolar (112‾2) InAlN layers grown on AlN templates using MOVPE. Issue 1 (12th November 2015)

• Record Type: Journal Article
• Authors: Dinh, Duc V.; Li, Haoning; Parbrook, Peter J.
• Is Part Of: Physica status solidi. Volume 253:Issue 1(2016)
• Page Start: 99
• Page End: 104
• Publication Date: 2015-11-12
• Subjects: indium aluminum nitride -- Morphology -- MOVPE -- semipolar; Solid state physics -- Periodicals; Solids -- Periodicals; Atomic structure -- Periodicals; 530.41
• DOI: 10.1002/pssb.201552264
• Languages: English
• ISSNs: 0370-1972

Abstract

Abstract: We report on metalorganic vapor phase epitaxial growth of InAlN layers on (0001) and (11 2 ‾ 2) AlN templates at different temperatures (725–800 °C). The indium content (8.0–15.2%) of the (11 2 ‾ 2) InAlN layers was found to be lower compared to that for the (0001) layers (9.0–23.0%). The higher indium content of the (0001) layers was attributed to a high density of small hillocks and a larger degree of relaxation. The small hillocks on the (0001) layer surface acted as quantum‐dot‐like structures that caused a stronger emission at longer wavelength compared to weaker emission at shorter wavelength from a "bulk" layer underneath. A large Stokes‐shift of about 300 and 480 meV was observed for the (0001) and ( 11 ̅ 2 2 ) layers, respectively. The larger shift of the (11 2 ‾ 2) layers was attributed to a higher degree of localization. The larger degree of localization and higher unintentional oxygen incorporation enhanced the luminescence intensity of the (11 2 ‾ 2) layers compared to that for the (0001) layers.