Electrical and Optical Properties of Multi-Shaped ZnO Micro and Nanostructures: Shape Dependence Sensitivity

In this paper we report the electrical and optical properties of ZnO micro and nanostructures. These structures are grown by catalyst free direct vapor method and the morphology consists of nanowires and microspheres embedded in the network of nanowires. The photoluminescence properties indicate the absence of defect band at 510 nm in case of nanowires- microspheres morphology. The prototype UV photoconductive- type sensors were fabricated from both ZnO structures and the electrical properties were studied. The electrical properties are found to vary with the morphology of samples. To understand the opto-electronic properties the UV sensors were studied (under UV illumination) at varying oxygen pressure ambient in a vacuum sealed chamber and the decay time of the UV sensors were measured.