Realization of defect-free epitaxial core-shell GaAs/AlGaAs nanowire heterostructures

Journal Article · Mon Oct 13 04:00:00 EDT 2008 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3002299· OSTI ID:21175659

Tambe, Michael J; Lim, Sung Keun; Smith, Matthew J; Gradecak, Silvija ^[1]; Allard, Lawrence F ^[2]

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1. Department of Materials and Engineering, Massachusetts Institute of Technology, Cambridge Massachusetts 02139 (United States)
2. High Temperature Materials Laboratory, Oak Ridge National Laboratory, Oak Ridge Tennessee 37831 (United States)

We report the controlled growth of vertically aligned GaAs/AlGaAs core-shell nanowires. By optimizing the shell deposition temperature and catalyst density we maintain high temperature stability and achieve defect-free epitaxial AlGaAs shell deposition with high aluminum incorporation. Energy dispersive x-ray analysis determines the shell composition to be Al{sub 0.9}Ga{sub 0.1}As and measures the uniformity of the shell thickness. Lattice-resolved high-angle annular dark-field scanning transmission electron microscopy images confirm the core-shell interface to be defect-free, epitaxial, and atomically sharp. The ability to realize GaAs/AlGaAs core-shell nanowires with precise control over the morphology and composition is essential to the development of nanowire-based high mobility electronics.

• OSTI ID: 21175659
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 15 Vol. 93; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM
ALUMINIUM ARSENIDES
CARRIER MOBILITY
CATALYSTS
CHEMICAL ANALYSIS
CRYSTAL DEFECTS
CRYSTAL GROWTH
DEPOSITION
EPITAXY
GALLIUM ARSENIDES
MORPHOLOGY
OPTIMIZATION
QUANTUM WIRES
SCANNING ELECTRON MICROSCOPY
SEMICONDUCTOR MATERIALS
TRANSMISSION ELECTRON MICROSCOPY