Investigation of Hydration Reaction-Induced Protons Transport in Etching-Stop a-InGaZnO Thin-Film Transistors

In this letter, protons (hydrogen ions, H
⁺
ions) transport-induced unstable transient electrical characteristics were found and studied in the etching-stop-layer in via-contact-type amorphous-indium-gallium-zinc-oxide thin-film transistors (a-IGZO TFTs) for the first time. By applying negative gate bias stress, more water molecules will be absorbed on the surface of the passivation layer, and thus the transmission of net protons in the etching-stop will increase. The proton transport model established in this letter can effectively analyze the a-IGZO TFTs instability using the threshold voltage (V
_T
) determined from the current-voltage measurements, and which is unstable in a moist environment.