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HL: Fachverband Halbleiterphysik
HL 25: Transport
HL 25.7: Vortrag
Montag, 14. März 2011, 17:30–17:45, POT 151
Controlling the transport properties of InAs nanowires by Si doping — •Karl Weis1,3, Stephan Wirths1,3, Andreas Winden1,3, Kamil Sladek1,3, Thomas Weirich2,3, Thomas Schäpers1,3, Hilde Hardtdegen1,3, Hans Lüth1,3, Nataliya Demarina1,3, and Detlev Grützmacher1,3 — 1Institut für Bio- und Nanosysteme (IBN), Forschungszentrum Jülich, Germany — 2Gemeinschaftslabor für Elektronenmikroskopie, RWTH Aachen, Germany — 3JARA, Fundamentals of Future Information Technology
InAs nanowires are attractive building blocks for nanoelectronic devices, e. g. field-effect transistors. For concrete applications, it is important to understand the interplay between their crystal structure and transport properties. By doping, the latter can be tuned.
We fabricated InAs nanowires by selective-area metal-organic vapour phase epitaxy. Using Si2 H6 as a dopant, samples with five different doping levels, each set comprising 30 to 100 nanowires (typical length and diameter: 3 µ m and 100 nm, respectively), were prepared.
From I-V measurements and field effect transistor measurements using a SiO2 back gate, we get a clear positive correlation between doping level and conductivity/carrier concentration/mobility. The conductivity can be tuned between (12.9 ± 0.8) S/cm and (560 ± 120) S/cm. Furthermore, transmission electron micrographs show an influence of doping on the crystal structure of the wires. Magneto-transport measurements are performed to quantify the effect of stacking faults on the conductivity. At low temperatures around 4 K, the I-V characteristics show indications of single electron tunneling.