High-Performance Light-Erasable Memory and Real-Time Ultraviolet Detector Based on Unannealed Indium-Gallium-Zinc-Oxide Thin-Film Transistor

Abstract

A light-erasable memory and a real-time ultraviolet (UV) detector were developed from an amorphous indium-gallium-zinc-oxide (IGZO) thin-film transistor fabricated at room temperature without post-annealing. The natural defects within the IGZO or at the dielectric interface serve as electron traps to support a writing operation (switching down the channel conductance). A negative gate bias accompanied by UV illumination performs an erasing operation (switching up the channel conductance). After the writing/erasing of the proposed memory, an on/off ratio greater than 10(4) was maintained for a testing duration of 10 000 s. A real-time UV detector was also developed, and a light/dark ratio of roughly 10(4) was demonstrated.