Active matrix substrate and method for producing same, and in-cell touch panel-type display device

• US 10,388,676 B2
• Filed: 08/04/2016
• Issued: 08/20/2019
• Est. Priority Date: 08/10/2015
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Saitoh, Takao, Kanzaki, Yohsuke, Nakazawa, Makoto, Ito, Kazuatsu, Kaneko, Seiji
• Primary Examiner(s): Rizkallah, Kimberly N
• Assistant Examiner(s): Ramallo, Gustavo G
• Application Number:
  US15/743,369
• Publication Number:
  US 20180204853A1
• Time in Patent Office: 1,111 Days
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/1343 Electrodes reflective electrodes G02F1/133553
• CPC Class Codes: G02F 1/134372 for fringe field switching [FFS] where the common electrode is not patterned
• CPC Class Codes: G02F 1/1345 Conductors connecting electrodes to cell terminals
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• 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
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: H01L 21/768 Applying interconnections to be used for carrying current between separate components within a device comprising conductors and dielectrics
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1248 with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
• CPC Class Codes: H01L 29/786 Thin film transistors, i.e. transistors with a channel being at least partly a thin film transistors having only the source or the drain region on an insulator layer H01L29/0653; thin film FinFETs H01L29/785

Abstract

An active matrix substrate (1001) includes a connecting portion (101). The connecting portion. (101) includes a lower conductive layer supported by a substrate; a first insulating layer formed so as to cover the lower conductive layer (2) and having a contact hole (6p) that exposes a part of the lower conductive layer (2); a bottom conductive film (4) that is disposed in the contact hole (6p) and covers at least a part of the exposed part of the lower conductive layer (2), the exposed part being exposed by the contact hole (6p); a second insulating layer (9) that is formed on the first insulating layer (6) and in the contact hole (6p), is in contact with the bottom conductive film (4) in the contact hole (6p), and has an opening (9p) that exposes a part of the bottom conductive film (4); and an upper conductive layer (8) that is disposed on the second insulating layer (9) and in the opening (9p) and is in contact with the bottom conductive film (4) in the opening (9p). The entire bottom conductive film (4) is located on the substrate side relative to the upper surface of the first insulating layer (6).

Claims

1. An active matrix substrate comprising a substrate and a connection portion supported by the substrate,

wherein the connecting portion includes:

a lower conductive layer supported by the substrate,

a first insulating layer formed so as to cover the lower conductive layer, the first insulating layer having a plurality of contact holes that exposes a part of the lower conductive layer,

a bottom conductive film that is disposed in the contact hole and covers at least a part of the exposed part of the lower conductive layer, the exposed part being exposed by the contact hole,

a second insulating layer that is formed on the first insulating layer and in the contact hole and that is in contact with the bottom conductive film in the contact hole, the second insulating layer having an opening that exposes a part of the bottom conductive film, and

an upper conductive layer that is disposed on the second insulating layer and in the opening and that is in contact with the bottom conductive film in the opening,

the entire bottom conductive film being located on the substrate side relative to an upper surface of the first insulating layer, and

further comprising a plurality of thin film transistors supported by the substrate;

a plurality of first transparent electrodes; and

a plurality of second transparent electrodes disposed over the first transparent electrodes with the second insulating layer interposed therebetween,

wherein the lower conductive layer is formed from a conductive film from which a source electrode of the thin film transistor is also formed,

the upper conductive layer is formed from a conductive film from which the second transparent electrode is also formed, and

the bottom conductive film includes a transparent conductive layer formed from a transparent conductive film from which the first transparent electrode is also formed.

2. The active matrix substrate according to claim 1, wherein the second insulating layer is disposed so as to cover the bottom conductive film, at least a part of a side wall of the contact hole, and at least a part of the upper surface of the first insulating layer.

3. The active matrix substrate according to claim 1, wherein the bottom conductive film is disposed so as to cover an area ranging from a bottom to a part of the side wall of the contact hole and has an end face on the side wall of the contact hole, and

the second insulating layer covers the end face of the bottom conductive film.

4. The active matrix substrate according to claim 1, wherein the bottom conductive film includes a metal layer.

5. The active matrix substrate according to claim 1, wherein the bottom conductive film includes a transparent conductive layer.

6. The active matrix substrate according to claim 1, wherein the bottom conductive film has a multilayer structure including a transparent conductive layer and a metal layer.

7. The active matrix substrate according to claim 1, wherein the exposed part of the bottom conductive film, the exposed part being exposed by the opening, has thickness d, as measured in a normal direction of a surface of the substrate, of 50 nm or more.

8. The active matrix substrate according to claim 1, wherein the first insulating layer has a thickness of 1 μ

m or more and 3 μ

m or less.

9. The active matrix substrate according to claim 1, wherein the upper surface of the first insulating layer is substantially flat.

10. The active matrix substrate according to claim 1, wherein the first insulating layer includes an organic insulating layer.

11. The active matrix substrate according to claim 1, wherein the bottom conductive film includes a conductive layer formed from a conductive film from which a wire for driving an in-cell touch panel is also formed.

12. A method for producing an active matrix substrate, comprising:

a step (A) of forming a lower conductive layer on a substrate;

a first insulating layer forming step (B) of forming a first insulating layer that covers the lower conductive layer, the first insulating layer having a plurality of contact holes that exposes a part of the lower conductive layer;

a bottom conductive film forming step (C) of forming a bottom conductive film in the contact hole such that the bottom conductive film covers at least a part of the exposed part of the lower conductive layer, the exposed part being exposed by the contact hole, the bottom conductive film having an upper surface located on the substrate side relative to an upper surface of the first insulating layer;

a second insulating layer forming step (D) of forming a second insulating layer on the first insulating layer and in the contact hole such that the second insulating layer is in contact with the bottom conductive film in the contact hole, the second insulating layer having an opening that exposes at least a part of the bottom conductive film; and

a step (E) of forming an upper conductive layer on the second insulating layer and in the opening such that the upper conductive layer is in contact with the bottom conductive film in the opening,

wherein, by these steps, a connecting portion that electrically connects the lower conductive layer and the upper conductive layer to each other is formed, and

the active matrix substrate further includes a plurality of thin film transistors, a plurality of first transparent electrodes, and a plurality of second transparent electrodes disposed over the first transparent electrodes with the second insulating layer interposed therebetween,

in the step (A), the lower conductive layer is formed from a conductive film from which a source electrode of the thin film transistor is also formed,

in the step (C), the bottom conductive film includes a transparent conductive layer, and the transparent conductive layer is formed from a transparent conductive film from which the first transparent electrode is also formed, and

in the step (E), the upper conductive layer is formed from a conductive film from which the second transparent electrode is also formed.

13. The method of producing an active matrix substrate according to claim 12, wherein the bottom conductive film includes a conductive layer formed from a conductive film from which a wire for driving an in-cell touch panel is also formed.