| abstract |
An object of the present invention is to provide a thin film transistor that has high mobility, a high on-off ratio, and can be efficiently manufactured. The present invention has a source electrode 50, a drain electrode 60, a gate electrode 20, a gate insulating film 30, and a channel layer 40 made of an oxide semiconductor, and the channel carrier 40 has an average carrier concentration of 1 × 10 16 / cm. 3 to 5 × 10 19 / cm 3 , and there is a carrier concentration region 42 higher than the average carrier concentration on the gate insulating film 30 side of the channel layer 40, and the channel layers 40 are substantially the same. A thin film transistor 1 having the composition: |