Self-Heating-Effect-Induced Degradation Behaviors in a-InGaZnO Thin-Film Transistors

This letter investigates degradation behaviors induced by the self-heating effect for amorphous indium-gallium-zinc-oxide (IGZO) (a-IGZO) thin-film transistors (TFTs). Both the surrounding oxide and other thermal insulating material and the low thermal conductivity of the IGZO layer itself cause the self-heating effect in a-IGZO TFTs. The heated channel layer enhances threshold voltage shift, and the evolution of threshold voltage shift is found to be dominated by charge-trapping effect. Further verifications indicate that the degree of threshold voltage shift is dependent on stress power only, and a wider channel leads to more severe self-heating effect.