Origin of self-heating effect induced asymmetrical degradation behavior in InGaZnO thin-film transistors

Abstract

This letter investigates asymmetrical degradation behavior induced by the self-heating effect in InGaZnO thin-film transistors. Both the surrounding oxide and other thermal insulating material, as well as the low thermal conductivity of the InGaZnO layer itself, cause the self-heating effect in InGaZnO thin-film transistors. The heated channel layer enhances threshold voltage shift, and the evolution of threshold voltage shift is found to be dominated by charge-trapping effect. Moreover, a non-uniform distribution of channel carrier concentration leads to an uneven temperature distribution through the InGaZnO active layer and results in the asymmetrical degradation behavior after self-heating operation.