Abstract: A thin-film transistor substrate includes: an insulating substrate; a gate electrode disposed on the insulating substrate; a gate insulating layer that covers the gate electrode; an oxide-semiconductor layer that is disposed on the gate insulating layer and is partly over the gate electrode; an interlayer insulating layer that covers a top and a side of the oxide-semiconductor layer; and a source electrode and a drain electrode that are disposed on the interlayer insulating layer. The interlayer insulating layer includes first, second, and third interlayer insulating layers that are laminated on the oxide-semiconductor layer in this order, and includes a first opening where the source electrode is in contact with the oxide-semiconductor layer and a second opening where the drain electrode is in contact with the oxide-semiconductor layer in regions that are over the oxide-semiconductor layer in a plan view.

Abstract: Disclosed is a method of forming wiring. The method includes the steps of: depositing a metal thin film (12) of copper (Cu) on a glass substrate (11) serving as a base; forming an insulating film or a metal insulating film (131) containing no Cu on the metal thin film (12); patterning a photoresist (14) by photolithography on the insulating film (131); etching a liner film (13) by isotropic dry etching using the photoresist (14) as an etching mask; and after the etching of the liner film (13), removing the photoresist (14), and then removing part of the metal thin film (12) by isotropic wet etching using the liner film (13) as an etching mask, thereby forming metal wiring (12a).

Abstract: Disclosed is a method of forming wiring. The method includes the steps of: depositing a metal thin film (12) of copper (Cu) on a glass substrate (11) serving as a base; forming an insulating film or a metal insulating film (131) containing no Cu on the metal thin film (12); patterning a photoresist (14) by photolithography on the insulating film (131); etching a liner film (13) by isotropic dry etching using the photoresist (14) as an etching mask; and after the etching of the liner film (13), removing the photoresist (14), and then removing part of the metal thin film (12) by isotropic wet etching using the liner film (13) as an etching mask, thereby forming metal wiring (12a).