Laterally grown show better performance: ZnO nanorods network based field effect transistors

Abstract

In this work, ZnO based field effect transistors have been demonstrated using self-aligned nanorods (NRs) network synthesized through a facile hydrothermal route. To control the alignment and orientation of nanorods two additives viz. Potassium Permanganate (KMnO4) and Potassium Dichromate (K2Cr2O7) were added into the precursor solution. The effect of additive was studied through structural and optical characterization of nanorods. Further, these nanorods were used as an active layer in field effect transistors (FETs) and the estimated field effect mobility and current on/off ratio of the devices were 0.56 × 10−4 cm2/V s and 10 for vertically aligned and 9.04 cm2/V s and 6 × 103 for laterally aligned NRs network respectively. It was observed that the transport properties of charges are associated with the alignment, size, interface junctions of NRs/NRs or NRs/electrode and trap defects/states on the surface. The possible mechanism of charge transport in network path has been systematically discussed.