AVS 51st International Symposium
    Nanometer-scale Science and Technology Thursday Sessions
       Session NS2-ThM

Paper NS2-ThM8
Direct Atomically Resolved Imaging inside a Nanowire

Thursday, November 18, 2004, 10:40 am, Room 213D

Session: Nanowires I
Presenter: A. Mikkelsen, Lund University, Sweden
Authors: A. Mikkelsen, Lund University, Sweden
N. Skold, Lund University, Sweden
L. Ouattara, Lund University, Sweden
M. Borgstrom, Lund University, Sweden
J.N. Andersen, Lund University, Sweden
L. Samuelson, Lund University, Sweden
W. Seifert, Lund University, Sweden
E. Lundgren, Lund University, Sweden
Correspondent: Click to Email
Semiconductor nanowires are perceived as future components in nanoelectronics and photonics. Applications, such, bio/chemical sensors , n- p- type diode logic and single nanowire lasers have already been realized in the laboratory. Because of the extremely small dimensions of a nanowire, atomic scale structural features can have a significant impact on their properties. The large surface to bulk ratio of tailor-made nano-crystallites and low dimensional systems as compared to usual bulk crystals can result in new crystal structure and morphology not found in bulk equivalents. Therefore, structural methods that address these issues are highly desirable. One such method is Scanning Tunneling Microscopy (STM) that has revolutionized our perception nano-scale objects and low-dimensional systems. In this study we demonstrate a new powerful method to image individual atoms inside freestanding III-V semiconductor nanowires using a combination of Cross-Sectional Scanning Tunneling Microscopy and a novel embedding scheme. We image areas of the nanowire with atomic resolution both along the wire, and through the face of the wire. Utilizing this method we for example image the individual atoms in planar twin segments of the wire and show that individual atomic impurities in a GaAs nanowire can be imaged. Finally we image the GaAs nanowire at the substrate interface revealing intriguing details about the initial growth of the nanowire.