Liquid crystal display device and touch panel

Abstract

To provide a highly reliable liquid crystal display device including flexible substrates and a crystalline oxide semiconductor film for a backplane. The device includes a flexible first substrate, a flexible second substrate facing the first substrate, and a liquid crystal layer sealed between the substrates with a sealing member. The first substrate is provided with a layer including a transistor, an organic resin film over the transistor, a pixel electrode and a common electrode over the organic resin film, which partly overlap with each other with an insulating film provided therebetween, and an alignment film thereover. The transistor includes a crystalline oxide semiconductor film as a semiconductor layer where a channel is formed. Drying treatment is performed on the layer before the liquid crystal layer is sealed between the substrates, and steps from the drying treatment to sealing of the liquid crystal layer are performed without exposure to the air.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a liquid crystal display device including a transistor using an oxide semiconductor film and a touch panel including the liquid crystal display device.[0003]2. Description of the Related Art[0004]Transistors which are used for many liquid crystal display devices and organic EL display devices have been formed using a silicon semiconductor film such as an amorphous silicon film or a polycrystalline silicon film.[0005]Instead of the silicon semiconductor film, a technique in which an oxide semiconductor film is used for transistors has attracted attention.[0006]For example, a technique is disclosed in which a transistor manufactured using an In—Ga—Zn oxide film as an oxide semiconductor film is used as a switching element or the like of a pixel (see Patent Documents 1 and 2).[0007]Further, we develop a technique in which an oxide semiconductor film having a noble crystal structure is manuf...

AI Technical Summary

Benefits of technology

The patent is about a new type of semiconductor called oxide semiconductor, which has wider band gap and lower intrinsic carrier density than silicon. Using this semiconductor in a transistor can result in extremely low off-state current, which helps to reduce power consumption in display devices. Furthermore, using a crystalline oxide semiconductor film can increase the density of pixels and achieve higher definition of display devices.

Problems solved by technology

It is known that power consumption of liquid crystal display devices varies depending on a method for applying an electric field to a liquid crystal layer (display mode).

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