Method for manufacturing display device

摘要

One object is to provide a method for manufacturing a display device in which shift of the threshold voltage of a thin film transistor including an oxide semiconductor layer can be suppressed even when ultraviolet light irradiation is performed in the process for manufacturing the display device. In the method for manufacturing a display device, ultraviolet light irradiation is performed at least once, a thin film transistor including an oxide semiconductor layer is used for a switching element, and heat treatment for repairing damage to the oxide semiconductor layer caused by the ultraviolet light irradiation is performed after all the steps of ultraviolet light irradiation are completed.