Ultraviolet Photo-Annealing Process for Low Temperature Processed Sol-Gel Zinc Tin Oxide Thin Film Transistors

Abstract

Sol-gel zinc tin oxide (ZTO) thin film transistors (TFTs) were fabricated at a low temperature of 250°C using an ultraviolet (UV) photo-annealing process. A stable ZTO sol-gel solution was produced and showed considerable absorption in UV due to the incorporation of a chelating agent, acetylacetone, which also acts as a UV-activator. The UV photo-annealing and vacuum annealing improve the electrical performance of the ZTO TFT with mobility of 2 cm2/ V·s by effective dissociation of organic groups and promotion of metal-oxide-metal bonds formation, confirmed by X-ray photoelectron spectroscopy of the ZTO films.