DISPLAY DEVICE INCLUDING TRANSISTOR AND MANUFACTURING METHOD THEREOF

摘要

The purpose of the present invention is to provide a display device which operates stably using a transistor having stable electric characteristics. When the display device is manufactured by using the transistor in which an oxide semiconductor layer is used for a channel formation region, a gate electrode is further disposed over a transistor which is applied at least to a driver circuit. When the transistor in which the oxide semiconductor layer is used for the channel formation region is manufactured, the oxide semiconductor layer is subjected to heat treatment so as to be dehydrated or dehydrogenated. Thus, impurities such as moisture existing on an interface between the oxide semiconductor layer and a gate insulating layer provided below and in contact with the oxide semiconductor layer can be reduced.