Display device and manufacturing process of display device

A display device, comprising:

• an insulating substrate;
• and
• a thin film transistor formed on the insulating substrate,
• wherein the thin film transistor comprises:
• a conductive layer provided with a gate electrode;
• a gate insulating layer which is provided on the conductive layer and contains an insulating material;
• an oxide semiconductor film which is provided in contact with an upper surface of the gate insulating layer and is provided above the gate electrode;
• a source electrode which is provided in contact with a first region provided in an upper surface of the oxide semiconductor film;
• a drain electrode which is provided in contact with a second region spaced apart from the first region, the second region being provided in the upper surface of the oxide semiconductor film;
• and
• a channel protective film which contains the insulating material and is provided in contact with a third region provided between the first region and the second region, the third region being provided in the upper surface of the oxide semiconductor film,
• wherein, in plan view, a first portion of the oxide semiconductor film, which overlaps with the gate electrode, is a part of a larger second portion of the oxide semiconductor film, which overlaps with the channel protective film, and
• wherein a portion of the oxide semiconductor film, except for at least one part of the first portion of the oxide semiconductor film, has a resistance lower than a resistance of another part of the first portion of the oxide semiconductor film.