Composition pulling effect and strain relief mechanism in AlGaN/AlN distributed Bragg reflectors

Journal Article · Mon Jun 27 00:00:00 EDT 2011 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3605681· OSTI ID:21518503

Liu, B; Zhang, R; Ji, X L; Fu, D Y; Xie, Z L; Chen, D J; Chen, P; Jiang, R L; Zheng, Y D ^[1]; Zheng, J G ^[2]

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1. Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials, School of Electronic Science and Engineering, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing 210093 (China)
2. California Institute for Telecommunications and Information Technology, University of California, Irvine, California 92697-2800 (United States)

We report on the composition pulling effect and strain relief mechanism in AlGaN/AlN distributed Bragg reflectors (DBRs) grown on GaN template/{alpha}-Al{sub 2}O{sub 3}(0001) by metal organic chemical vapor deposition. The reciprocal space mapping contours reveal that these DBRs are coherently grown. Cross-section transmission electron microscopy image of the AlGaN/AlN DBRs and the energy-dispersive x-ray analysis indicate that an AlGaN layer with gradient Al composition is located between the Al{sub 0.4}Ga{sub 0.6}N and AlN layers along the [0001] direction. It is attributed to the fact that Ga atoms in AlGaN are pulled and segregated to the upper layer by the strain. The density of strain energy is estimated to reduce more than one order by forming this quasi-three-sublayer structure comparing to the designed bi-sublayer structure.

• OSTI ID: 21518503
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 26 Vol. 98; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOY SYSTEMS
ALUMINIUM COMPOUNDS
ALUMINIUM NITRIDES
ALUMINIUM OXIDES
BRAGG REFLECTION
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
COATINGS
CROSS SECTIONS
DENSITY
DEPOSITION
ELECTROMAGNETIC RADIATION
ELECTRON MICROSCOPY
FABRICATION
GALLIUM COMPOUNDS
GALLIUM NITRIDES
IONIZING RADIATIONS
LAYERS
MATERIALS
MICROSCOPY
NITRIDES
NITROGEN COMPOUNDS
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PNICTIDES
RADIATIONS
REFLECTION
SEMICONDUCTOR MATERIALS
STRAINS
SURFACE COATING
TERNARY ALLOY SYSTEMS
TRANSMISSION ELECTRON MICROSCOPY
X RADIATION