Display device

• US 9,417,475 B2
• Filed: 02/20/2014
• Issued: 08/16/2016
• Est. Priority Date: 02/22/2013
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Tanabe, Toru, Fukutome, Takahiro
• Primary Examiner(s): Dudek, James
• Application Number:
  US14/184,977
• Publication Number:
  US 20140240617A1
• Time in Patent Office: 908 Days
• US Class Current: 1/1
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/136209 Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element
• CPC Class Codes: G02F 1/136222 Colour filters incorporated in the active matrix substrate
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A display device having a novel structure that can improve reliability is provided. It lowers reliability to form a structure by using a photomask, such as a color filter on a rear side of a substrate. With this display device, a transistor and the color filter is provided over a first substrate, a touch sensor is provided on a first surface of a second substrate, and the structure is not provided on a second surface of the second substrate. Consequently, the display device with the touch sensor can perform high reliability.

Claims

1. A display device comprising:

a transistor over a first substrate;

a first insulating film over the transistor;

a color filter over the first insulating film;

a second insulating film over the color filter;

a pixel electrode over the second insulating film, the pixel electrode being electrically connected to a terminal of the transistor;

a liquid crystal layer over the pixel electrode;

an alignment film over the liquid crystal layer;

a second substrate over the alignment film;

a first electrode, a second electrode, and a third electrode over the second substrate;

a third insulating layer over the first electrode, the second electrode, and the third electrode; and

a fourth electrode over the insulating layer,

wherein the first electrode is electrically connected to the second electrode through the fourth electrode,

wherein the third electrode is electrically isolated from the first electrode, the second electrode, and the fourth electrode, and

wherein the alignment film is in contact with a first surface of the second substrate, and the first electrode, the second electrode, and the third electrode are in contact with a second surface of the second substrate.

2. The display device according to claim 1,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

3. The display device according to claim 1,

wherein a black matrix is in contact with the pixel electrode.

4. A display device comprising:

a transistor over a first substrate;

a first insulating film over the transistor;

a color filter over the first insulating film;

a second insulating film over the color filter;

a pixel electrode and a common electrode over the second insulating film, the pixel electrode being electrically connected to a terminal of the transistor;

a liquid crystal layer over the pixel electrode and the common electrode;

an alignment film over the liquid crystal layer;

a second substrate over the alignment film;

a first electrode, a second electrode, and a third electrode over the second substrate;

a third insulating layer over the first electrode, the second electrode, and the third electrode; and

a fourth electrode over the insulating layer,

wherein the first electrode is electrically connected to the second electrode through the fourth electrode,

wherein the third electrode is electrically isolated from the first electrode, the second electrode, and the fourth electrode, and

wherein the alignment film is in contact with a first surface of the second substrate, and the first electrode, the second electrode, and the third electrode are in contact with a second surface of the second substrate.

5. The display device according to claim 4,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

6. The display device according to claim 4,

wherein a black matrix is in contact with the pixel electrode.