| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a thin film transistor (TFT) less in amount of variation in a threshold voltage against light and bias stress and excellent in stability while maintaining high electric field effect mobility, in a back channel etch type thin film transistor including an oxide semiconductor but having no etch stopper layer.SOLUTION: A thin film transistor of the present invention includes a first source electrode/drain electrode and a second source electrode/drain electrode, in order from a substrate side. The thickness of the first source electrode/drain electrode is 20 nm or more and 100 nm or less. When a cross section of the TFT in a lamination direction is observed, the first source electrode/drain electrode and the second source electrode/drain electrode have a step-like cross-sectional structure, and the terminal portion of the first source electrode/drain electrode in a channel length direction is disposed so as to be longer within a range of 200 nm or more and 1,000 nm or less as compared with the terminal portion of the second source electrode/drain electrode.</p> |
