Abstract: A display device includes a drive transistor and a switching transistor formed by layering an inorganic insulating film, an oxide semiconductor layer, an upper gate insulating layer, an upper gate electrode, and an interlayer insulating film. The drive transistor and the switching transistor include an oxide semiconductor film formed of the oxide semiconductor layer and provided in an island shape corresponding to the drive transistor and an island shape corresponding to the switching transistor, and the oxide semiconductor film includes a channel region overlapping with the upper gate electrode corresponding to the oxide semiconductor film, and a source region and a drain region. The drive transistor is provided with a lower gate electrode and a lower gate insulating layer between the inorganic insulating film and the oxide semiconductor layer. The length of lower gate electrode is less than or equal to the length of upper gate electrode.

Abstract: A display device includes a transistor including: a substrate; a lower electrode; a lower insulating film; an oxide semiconductor layer; a gate insulating film; and a gate electrode stacked on top of an other in a stated order. The gate electrode matches the gate insulating film in plan view. The oxide semiconductor layer includes: a channel region across the gate insulating film from the gate electrode; and a source region and a drain region provided to sandwich the channel region. The lower electrode extends to intersect with the oxide semiconductor layer in plan view. The lower electrode has: a source-side end face positioned toward the source region and overlap with the source region; and a drain-side end face positioned toward the drain region and overlap with the channel region.