%0 Journal Article
%T Observation of fluctuation-induced tunneling conduction in micrometer-sized tunnel junctions
%A Yu-Ren Lai
%A Kai-Fu Yu
%A Yong-Han Lin
%A Jong-Ching Wu
%J AIP Advances
%D 2012
%I AIP Publishing LLC
%R 10.1063/1.4749251
%X Micrometer-sized Al/AlOx/Y tunnel junctions were fabricated by the electron-beam lithography technique. The thin (ˇÖ 1.5¨C2 nm thickness) insulating AlOx layer was grown on top of the Al base electrode by O2 glow discharge. The zero-bias conductances G(T) and the current-voltage characteristics of the junctions were measured in a wide temperature range 1.5¨C300 K. In addition to the direct tunneling conduction mechanism observed in low-G junctions, high-G junctions reveal a distinct charge transport process which manifests the thermally fluctuation-induced tunneling conduction (FITC) through short nanoconstrictions. We ascribe the experimental realization of the FITC mechanism to originating from the formations of ˇ°hot spotsˇ± (incomplete pinholes) in the AlOx layer owing to large junction-barrier interfacial roughness.
%U http://link.aip.org/link/doi/10.1063/1.4749251