Ohmic and Schottky nanocontacts on ZnO nanorods

We report on fabrication and electrical characteristics of metal/ZnO nanorod heterostructure arrays. The metal/ZnO nanorod heterostructures were fabricated simply by evaporating metal on vertically well-aligned ZnO nanorods prepared by non-catalytic metalorganic vapor phase epitaxy (MOVPE). Transmission electron microscopy revealed that the metal/ZnO nanorod heterostructures exhibit an atomically sharp interface between ZnO and metal layers. Furthermore, electrical junction properties of the heterostructures were investigated using conducting probe atomic force microscopy. The electrical measurements of metal/ZnO heterostructure nanorod arrays exhibited either linear or rectifying I-V characteristic curves, depending on the metal deposited on ZnO nanorods.