| abstract |
An electric field including a gate electrode configured to apply a gate voltage, a source electrode and a drain electrode configured to transmit an electric signal, an active layer formed between the source electrode and the drain electrode, and a gate insulating layer formed between the gate electrode and the active layer As an effect transistor, the active layer includes at least two types of oxide layers including an A layer and a B layer, and the active layer includes the following conditions (1) and (2): Condition (1): The active layer contains three or more oxide layers including two or more layers A, and Condition (2): The band gap of the layer A is smaller than the band gap of the layer B, and the oxygen affinity of the layer A is equal to or higher than that of the layer B. Field-effect transistor that satisfies at least one of. |