GaAs/AlGaAs nanowire heterostructures studied by scanning tunneling microscopy

Summary, in English

We directly image the interior of GaAs/AlGaAs axial and radial nanowire heterostructures with atomic-scale resolution using scanning tunneling microscopy. We show that formation of monolayer sharp and smooth axial interfaces are possible even by vapor-phase epitaxy. However, we also find that instability of the ternary alloys formed in the Au seed fundamentally limits axial heterostructure control, inducing large segment asymmetries. We study radial core-shell nanowires, imaging even ultrathin submonolayer shells. We demonstrate how large twinning-induced morphological defects at the wire surfaces can be removed, ensuring the formation of wires with atomically flat sides.

• Author: Lassana Ouattara; Anders Mikkelsen; Niklas Sköld; Jessica Bolinsson; Thijs Knaapen; Elizabeta Cavar; Werner Seifert; Lars Samuelson; Edvin Lundgren
• Department/s: Synchrotron Radiation Research; Solid State Physics
• Publishing year: 2007
• Language: English
• Pages: 2859-2864
• Publication/Series: Nano Letters
• Volume: 7
• Issue: 9
• Links: http://dx.doi.org/10.1021/nl071550z
• Document type: Journal article
• Publisher: The American Chemical Society (ACS)
• Topic: Nano Technology
• Status: Published
• ISBN/ISSN/Other: ISSN: 1530-6992