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) which includes an oxide semiconductor and has a favorable rectification property is provided. In a transistor including an oxide semiconductor in which the hydrogen concentration is 5 x 1019 /cm3 or lower, a work function ?ms of a source electrode in contact with the oxide semiconductor, a work function ?md of a drain electrode in contact with the oxide semiconductor, and electron affinity ? of the oxide semiconductor satisfy ?ms = ?< ?md, and an area of contact between the drain electrode and the oxide semiconductor is larger than an area of contact between the source electrode and the oxide semiconductor. By electrically connecting a gate electrode and the drain electrode in the transistor, a non-linear element having a favorable rectification property can be achieved.