Display device and method for manufacturing display device

A method of manufacturing a display apparatus and a display apparatus. The display device having a display element; a thin film transistor for controlling the light emitting display element; and a signal line connected to the thin film transistor, a thin film transistor having: a gate electrode formed on an insulating substrate; so as to cover the gate electrode is formed in the substrate a gate insulating film; forming a channel layer on the gate insulating film; the channel layer and a source connected to the source electrode and the drain electrode, and the signal line mounting terminal portion has the structure: over a copper layer laminating a metal oxide layer, and the cross section of the terminal mounting portion and a trapezoidal portion covers the side surface of the terminal mounting portion and a peripheral upper surface of the protective film.