| 摘要 |
PROBLEM TO BE SOLVED: To provide a display device which operates stably by using a transistor having stable electrical characteristics.SOLUTION: In manufacture of a display device by applying a transistor in which an oxide semiconductor layer is used for a channel formation region, a gate electrode is further provided on the transistor which is applied to at least a driver circuit. In manufacture of the transistor in which the oxide semiconductor layer is used for the channel formation region, the oxide semiconductor layer is subjected to heat treatment so as to be dehydrated or dehydrogenated, and then, impurities such as moisture, existing in: an interface between the oxide semiconductor layer and a gate insulating layer provided in contact with the top and the bottom; and an interface between the oxide semiconductor layer and a protective insulating layer provided in contact with the top and the bottom, can be reduced. |
