Characterizations of Ohmic and Schottky-behaving contacts of a single ZnO nanowire

Bogdan Bercu (1) , Wei Geng (2) , Olivier Simonetti (1) , Serguei Kochtcheev (2) , Corinne Sartel (3) , Vincent Sallet (3) , Gilles Lerondel (2) , Michaël Molinari (1) , Louis Giraudet (1) , Christophe Couteau (2, 4)

1 LRN - Laboratoire de Recherche en Nanosciences - EA 4682
2 LNIO - Laboratoire de Nanotechnologie et d'Instrumentation Optique
3 GEMAC - Groupe d'Etude de la Matière Condensée
4 CINTRA - CNRS International - NTU - Thales Research Alliance

Current–voltage and Kelvin probe force microscopy (KPFM) measurements were performed on single ZnO nanowires. Measurements are shown to be strongly correlated with the contact behavior, either Ohmic or diode-like. The ZnO nanowires were obtained by metallo-organic chemical vapor deposition (MOCVD) and contacted using electronic-beam lithography. Depending on the contact geometry, good quality Ohmic contacts (linear I–V behavior) or non-linear (diode-like) contacts were obtained. Current–voltage and KPFM measurements on both types of contacted ZnO nanowires were performed in order to investigate their behavior. A clear correlation could be established between the I–V curve, the electrical potential profile along the device and the nanowire geometry. Some arguments supporting this behavior are given based on technological issues and on depletion region extension. This work will help to better understand the electrical behavior of Ohmic contacts on single ZnO nanowires, for future applications in nanoscale field-effect transistors and nano-photodetectors.

Domaines: Micro et nanotechnologies/Microélectronique; Optique / photonique

Bogdan Bercu, Wei Geng, Olivier Simonetti, Serguei Kochtcheev, Corinne Sartel, et al.. Characterizations of Ohmic and Schottky-behaving contacts of a single ZnO nanowire. Nanotechnology, 2013, 24 (41), pp.415202. ⟨10.1088/0957-4484/24/41/415202⟩. ⟨hal-02297041⟩