Semiconductor device and method for producing same

A semiconductor device comprising:

• a substrate;
• a gate electrode on the substrate;
• a gate insulating layer located over the gate electrode;
• an oxide semiconductor layer on the gate insulating layer;
• source and drain electrodes electrically connected to the oxide semiconductor layer;
• a first transparent electrode electrically connected to the drain electrode, the first transparent electrode being a pixel electrode;
• a dielectric layer located over the source and drain electrodes;
• and
• a second transparent electrode on the dielectric layer, wherein
• at least a portion of the second transparent electrode overlaps with the first transparent electrode with the dielectric layer interposed between them,
• a lower surface of the first transparent electrode contacts with a reducing insulating layer which has a property of reducing an oxide semiconductor included in the oxide semiconductor layer,
• the reducing insulating layer does not contact with a channel region of the oxide semiconductor layer, and
• the oxide semiconductor layer and the first transparent electrode are made of the same oxide film.