Fabrication of two-terminal devices using solution-synthesized Cu-doped ZnO nanorods and their photosensing properties

Abstract

The fabrication and characterization of two-terminal devices using solutionsynthesized Cu-doped ZnO nanorods and their photosensitive properties are reported in this work. Hydrothermally prepared ZnO and Cu:ZnO nanorods were characterized by SEM, EDS and PL studies. Two-terminal devices of ZnO and Cu:ZnO nanorods were prepared using a simple drop-casting on E-beam evaporated metal patterns. The aluminum metal patterns were produced using lithography and the lift-off technique. The current-voltage (I-V) characteristics of the nanorod devices show different shapes and current levels depending on the contact resistance and size of the nanorods. The photoresponse of the nanorods under different illumination conditions was analyzed. Both ZnO and Cu-doped ZnO show enhanced response under UV light excitation compared to halogen light excitation. The Cu-doped ZnO nanorods show an enhanced photosensitive property compared to undoped ZnO. This work demonstrates a simple fabrication technique of ZnO nanorod-based planar two-terminal devices.