Organic semiconductor device with protective spinel oxide layer

A semiconductor device comprising:

• a gate electrode;
• an insulating layer over the gate electrode;
• a semiconductor layer over the insulating layer;
• a source electrode over and in contact with the semiconductor layer;
• a drain electrode over and in contact with the semiconductor layer;
• and
• a protective layer configured to cover at least a part of a surface of the semiconductor layer, the source electrode, and the drain electrode, wherein
• the semiconductor layer includes a first region overlapping with the source electrode, a second region overlapping with the drain electrode, and a third region not overlapping with any of the source electrode and the drain electrode and overlapping with the gate electrode,
• the protective layer includes a spinel oxide,
• each of the first region, the second region and the third region comprises hydrogen,
• a hydrogen concentration of the first region, a hydrogen concentration of the second region, and a hydrogen concentration of the third region are substantially the same, and
• the protective layer does not substantially contain hydrogen.