Metal Oxide Film And Semiconductor Device

A semiconductor device comprising:

• a first gate electrode over a substrate;
• a first oxide semiconductor film over the first gate electrode;
• a first source electrode and a first drain electrode over and in electrical contact with the first oxide semiconductor film;
• a first conductive film;
• a first insulating film over and in contact with a top surface of the first source electrode, a top surface of the first drain electrode, and a top surface of the first conductive film;
• a second oxide semiconductor film over the first insulating film;
• a second gate electrode over the second oxide semiconductor film;
• a second conductive film;
• a second insulating film over and in contact with a top surface of the second gate electrode and a top surface of the second conductive film;
• a second source electrode and a second drain electrode over and in electrical contact with the second oxide semiconductor film;
• and
• a pixel electrode over and in electrical contact with one of the second source electrode and the second drain electrode,
• wherein the first gate electrode and the second conductive film overlap with each other,
• wherein the first conductive film and the second gate electrode overlap with each other, and
• wherein a width of the first conductive film is larger than a width of the second gate electrode in a channel length direction.