Non-linear element, display device including non-linear element, and electronic device including display device

摘要

A non-linear element, such as a diode, in which an oxide semiconductor is used and a rectification property is favorable is provided. In a thin film transistor including an oxide semiconductor in which the hydrogen concentration is less than or equal to 5×10¹⁹/cm³, the work function φms of a source electrode in contact with the oxide semiconductor, the work function φmd of a drain electrode in contact with the oxide semiconductor, and electron affinity χ of the oxide semiconductor satisfy φms≦χφmd. By electrically connecting a gate electrode and the drain electrode of the thin film transistor, a non-linear element with a more favorable rectification property can be achieved.