The role of oxygen in determining the electrical performance of ZnSnO nanofiber field-effect transistors

Abstract

In recent years, one-dimensional (1D) nanostructures, such as nanotubes, nanowires and nanofibers, have been extensively investigated as potential building blocks in nanoscale devices owing to their excellent physical and chemical properties. In this report, zinc tin oxide (ZnSnO) nanofiber networks (NFNs) were fabricated by electrospinning, and the surface morphologies, crystallinities, grain size distributions, and chemical compositions of the nanofibers annealed in different atmospheres were systematically investigated. To verify the possible applications, field-effect transistors (FETs) based on ZnSnO NFNs/SiO2 were integrated. It is found that the field-effect mobility (µFE) of FETs based on ZnSnO NFNs annealed in oxygen is an order of magnitude higher than those annealed in air. When high-κ ZrOx thin film was employed as gate dielectric, the operating voltage was substantially reduced and a high µFE of 21.58 cm2 V−1 s−1 was achieved for the FETs based on ZnSnO NFNs annealed at 500 °C in oxygen. FETs based on oxygen-annealed ZnSnO NFNs/ZrOx exhibit great potential for applications in low-cost and low-voltage devices.