Display device and electronic device

摘要

An object is, in a structure where switch circuits in a signal line driver circuit is placed over the same substrate as a pixel portion, to reduce the size of transistors in the switch circuits and to reduce load in the circuits during charging and discharging of signal lines due to the supply of data. A display device is provided which includes a pixel portion receiving a video signal, and a signal line driver circuit including a switch circuit portion configured to control output of the video signal to the pixel portion. The switch circuit portion includes a transistor over an insulating substrate. The transistor has a field-effect mobility of at least 80 cm2/Vs or more. The transistor includes an oxide semiconductor layer.

主权项

1. A display device comprising:
a pixel portion configured to receive a video signal; and a signal line driver circuit including a switch circuit portion configured to control output of the video signal to the pixel portion, the switch circuit portion including a transistor, wherein the transistor comprises:
an oxide semiconductor layer over a first insulating layer and a second insulating layer, the oxide semiconductor layer including a first region and a pair of second regions with the first region interposed therebetween;a gate electrode over the oxide semiconductor layer with a gate insulating film interposed therebetween;a first electrode, wherein the first electrode and the first insulating layer overlap with each other with one of the pair of second regions interposed therebetween;a second electrode, wherein the second electrode and the first insulating layer overlap with each other with the other of the pair of second regions interposed therebetween; anda sidewall insulating layer, wherein the sidewall insulating layer is in contact with a side surface of the gate electrode and one of the first electrode and the second electrode, wherein the second insulating layer is embedded in the first insulating layer, wherein one surface of the first region is in contact with the first insulating layer, and wherein one surface of each of the pair of second regions is in contact with at least the second insulating layer.