Objective
Free-standing III-V semiconductor nanowires, with diameters of about 20 to 80 nm at a length of several µm, offer tremendous possibilities for application in photovoltaics, optoelectronics, information technology as well as life-science. Semiconductor nanowire devices are not only smaller than conventional structures and significantly power-saving, but can even exhibit qualitatively novel behavior. Due to the small size and the very large surface to bulk ratio, the nanowire surface has a crucial influence on the performance of the entire device.
Up to now, the conductivity and other electric properties of single nanowire devices on one hand and the nanowire crystal and surface structure on the other hand could only be measured separately. Here, we will combine both approaches in a novel experimental setup, enabling us to achieve information on the atomic surface structure and local electronic properties of an individual nanowire as well as the global electric behavior of a device built by the same nanowire simultaneously. For this purpose, we will study single, individually contacted semiconductor nanowires using scanning tunneling microscopy and spectroscopy (STM), obtaining data on e.g. the chemical composition and atomic reconstruction of the nanowire surface as well as the local density of states and local variations of the band alignment. During these STM measurements, external source, drain and gate voltages can be applied to the nanowire device, revealing the complex interaction of the nanowire surface, local charge distribution, and global device performance like conductivity and other transport properties.
Topic(s)
Call for proposal
FP7-PEOPLE-2009-IEF
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Funding Scheme
MC-IEF - Intra-European Fellowships (IEF)Coordinator
22100 LUND
Sweden