Transistor, and a method of manufacturing a transistor

PROBLEM TO BE SOLVED: To provide a transistor improved in electrical characteristics when an oxide semiconductor is used, and a method of manufacturing the same.SOLUTION: A transistor includes a first insulating layer L1 provided on a gate electrode GE, and a semiconductor layer SC (InGaZnO) which is provided on the gate electrode GE via the first insulating layer L1 and contains a first contact portion CT1, a second contact portion CT2 and a channel portion CNL interposed between the first contact portion CT1 and the second contact portion CT2, the film thickness of the channel portion CNL being smaller than the film thickness H of the first contact portion CT1 and the second contact portion CT2, a channel protection film L2 having an opening provided above the first contact portion CT1 and the second contact portion CT2, a source electrode SE electrically connected to the first contact portion CT1 at the opening of the channel protection film L 2, and a drain electrode DE electrically connected to the second contact portion at the opening of the channel protection film L2.SELECTED DRAWING: Figure 1