Thin-film transistor substrate, method for manufacturing same, and liquid crystal display

A thin-film transistor substrate comprising:

• a first thin-film transistor and a second thin-film transistor disposed on a substrate,
• wherein
• the first thin-film transistor includes
• a first gate electrode disposed on the substrate,
• a first gate insulating film covering the first gate electrode,
• a first oxide semiconductor layer facing the first gate electrode via the first gate insulating film,
• a first source electrode and a first drain electrode that are disposed on a surface of the first oxide semiconductor layer and separated from each other, and
• a first insulating film disposed on the first oxide semiconductor layer, the first source electrode, and the first drain electrode, and
• the second thin-film transistor includes
• a second gate electrode disposed on the substrate,
• a second gate insulating film covering the second gate electrode,
• a second oxide semiconductor layer facing the second gate electrode via the second gate insulating film,
• a second insulating film disposed on the second oxide semiconductor layer, and
• a second source electrode and a second drain electrode that are disposed on surfaces of the second insulating film and the second oxide semiconductor layer and separated from each other.