A semiconductor device includes a oxide semiconductor layer, a gate electrode arranged above the oxide semiconductor layer, a gate insulation layer between the oxide semiconductor layer and the gate electrode, a first insulation layer arranged above the oxide semiconductor layer and arranged with a first aperture part, wiring including an aluminum layer arranged above the first insulation layer, the wiring being electrically connected to the oxide semiconductor layer via the first aperture part, a barrier layer including aluminum oxide above the first insulation layer, above the wiring and covering a side surface of the wiring, and an organic insulation layer arranged above the barrier layer.