Berlin 2012 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 33: Ge/Si II

HL 33.6: Vortrag

Dienstag, 27. März 2012, 10:45–11:00, EW 015

Tuning the Electronic Properties of Germanium Nanowires by Room Temperature Focused Ion Beam Implantation — •Clemens Zeiner¹, Alois Lugstein¹, Thomas Burchhart¹, Peter Pongratz², Justin G. Connell³, Lincoln J. Lauhon³, and Emmerich Bertagnolli¹ — ¹Institute for Solid State Electronics, TU Wien, Vienna, Austria — ²Institute for Solid State Physics, TU Wien, Vienna, Austria — ³Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois, United States

Germanium nanowires (Ge-NW) have moved in the focus of the nanoscience community as promising candidates for novel quantum devices due to their favourable material properties. Our investigations show outstanding effects of FIB ion implantation into Ge-NW. The NWs are grown using a VLS process and contacted by electron beam lithography. Low resistivity contacts were formed by Cu diffusion forming Cu₃Ge/Ge-NW heterostructures with atomically sharp interfaces. By FIB implantation of 30 keV Ga and Bi ions at room temperature, the Ge-NW conductivity increases up to 3 orders of magnitude with increasing ion fluence without further annealing. Four point measurements prove that the conductivity enhancement emerges from the modification of the wires themselves. The Ga distribution in the implanted Ge-NWs was measured using atom probe tomography. Finally the feasibility of improving the device performance of top-gated Ge-NW MOSFETs by FIB implantation is shown.