Nanoscale contacts between semiconducting nanowires and metallic graphenes
Date of this Version7-27-2012
Metal–semiconductor (M–S) junctions are important components in many semiconductor devices, and there is growing interest in realizing high quality M–S contacts that are optically transparent. In this paper, we present our investigations into the characteristics of M–S junction in a semiconducting ZnO nanowire that was directly grown on a multilayer graphene film (MGF). The synthesized nanowires were fabricated into two-terminal devices with MGF as one contact and Al as the other contact. By comparison with devices employing Al contacts at both ends, the nanowire resistivity and specific contact resistivity of the MGF–nanowire contact can be extracted. The extracted specific contact resistivity of the MGF–ZnO nanowire contact (1.5 × 10-5 Ω-cm2) is comparable to reported Al–ZnO contacts. Based on the assumption that thermionic-field emission is the dominant mechanism, we obtained the zero bias effective barrier height of 0.413 eV for the MGF–ZnO nanowire Schottky contact. We have thus demonstrated that as a result of the enhanced tunneling at the contact, the MGF–nanowire contact exhibits near-ohmic current-voltage characteristics with a low contact resistance which suggests MGF as a promising candidate for future transparent displays using ZnO nanowire transistors.
Electrical and Electronics | Electronic Devices and Semiconductor Manufacturing | Nanoscience and Nanotechnology | Nanotechnology fabrication