Method of forming a color filter touch sensing substrate

• US 8,142,250 B2
• Filed: 09/27/2011
• Issued: 03/27/2012
• Est. Priority Date: 12/03/2008
• Status: Active Grant

• Current Assignee: Optronic Sciences LLC (Lumina Innovations LLC)
• Original Assignee: AU Optronics Corporation
• Inventors: Chien, Yu-Feng, Huang, Chau-Shiang, Yang, Tun-Chun, Lee, Seok-Lyul
• Primary Examiner(s): Santiago, Mariceli
• Application Number:
  US13/245,890
• Publication Number:
  US 20120015464A1
• Time in Patent Office: 182 Days
• Field of Search: 445/24, 445/25, 430311-321, 345173-178
• US Class Current: 445/24
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• 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 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A method of forming a color filter touch sensing substrate integrates touch-sensing structures/elements of a touch panel into the inner side of the color filter substrate, which faces a thin film transistor substrate, and forms patterned assistant electrodes on the surfaces of the transparent sensing pads for decreasing the equivalent resistance of the touch-sensing structures/elements. Moreover, since an adjacent transparent conductive layer and an assistant electrode layer are patterned to form the transparent sensing pads and the patterned assistant electrodes, a simplified pattern-transferring process can be applied to the transparent sensing pads and the patterned assistant electrodes, or bridge structures can be formed from the assistant electrode layer for electrically connecting between some transparent sensing pads. Therefore, the forming process is simplified.

Claims

1. A method of forming a color filter touch sensing substrate, the color filter touch sensing substrate being disposed corresponding to a thin film transistor substrate, and a display medium layer being disposed between the color filter touch sensing substrate and the thin film transistor substrate, the method comprising:

providing a transparent substrate;

forming a black matrix on a side of the transparent substrate facing the thin film transistor substrate, wherein the black matrix is formed by insulating materials;

forming at least two first patterned assistant electrodes and at least two second patterned assistant electrodes on the side of the transparent substrate facing the thin film transistor substrate, the at least two first patterned assistant electrodes and the at least two second patterned assistant electrodes being disposed corresponding to part of the black matrix respectively, and the at least two first patterned assistant electrodes being electrically isolated from the at least two second patterned assistant electrodes;

forming a first transparent conductive layer on the side of the transparent substrate facing the thin film transistor substrate to cover the at least two first patterned assistant electrodes, at least two second patterned assistant electrodes, the black matrix, and part of the transparent substrate;

patterning the first transparent conductive layer to form at least two first transparent sensing pads, at least two second transparent sensing pads and at least one first bridge structure, the at least one first bridge structure electrically connecting to the at least two first transparent sensing pads, the at least two first transparent sensing pads being disposed on the at least two first patterned assistant electrodes and on the black matrix under the at least two first patterned assistant electrodes, the at least two second transparent sensing pads being disposed on the at least two second patterned assistant electrodes and on the black matrix under the at least two second patterned assistant electrodes, and the at least two first transparent sensing pads being electrically isolated from the at least two second transparent sensing pads; and

forming at least one second bridge structure electrically connecting to the at least two second transparent sensing pads, wherein the at least one second bridge is electrically isolated from the at least one first bridge structure.

2. The method of claim 1, further comprising:

forming a plurality of color filters on the at least two first transparent sensing pads and the at least two second transparent sensing pads;

forming a planarization layer on the color filters; and

forming a second transparent conductive layer on the planarization layer.

3. The method of claim 1, wherein before forming the at least one second bridge structure, the method further comprises:

forming at least one patterned insulating layer on the at least one first bridge structure, wherein the at least one second bridge structure crosses the at least one insulating layer so as to electrically connect to the at least two second transparent sensing pads.

4. The method of claim 1, wherein before forming the at least one second bridge structure, the method further comprises:

forming an insulating layer covering the at least two first transparent sensing pads, the at least two second transparent sensing pads, the black matrix, part of the transparent substrate and the at least one first bridge structure, the insulating layer having a plurality of openings to expose the at least two second transparent sensing pads partially, wherein the at least one second bridge structure connects electrically to the at least two second transparent sensing pads through the openings.

5. The method of claim 1, wherein the step of forming the at least two first patterned assistant electrodes and the at least two second patterned assistant electrodes comprises forming at least one alignment mark.

6. The method of claim 1, wherein at least a part of the at least two first and the at least two second patterned assistant electrodes comprises a plurality of conductive strips, and the black matrix comprises a plurality of strip regions, and wherein the width of each of the conductive strips is substantially 6 micrometers smaller than that of each of the strip regions.

7. A method of forming a color filter touch sensing substrate, the color filter touch sensing substrate being disposed corresponding to a thin film transistor substrate, and a display medium layer being disposed between the color filter touch sensing substrate and the thin film transistor substrate, the method comprising:

providing a transparent substrate;

forming a black matrix on a side of the transparent substrate facing the thin film transistor substrate, wherein the black matrix is formed by insulating materials;

forming an assistant electrode layer on the side of the transparent substrate facing the thin film transistor substrate to cover the transparent substrate and the black matrix;

patterning the assistant electrode layer to form at least two first patterned assistant electrodes, at least two second patterned assistant electrodes and at least one first bridge structure, the at least two first patterned assistant electrodes and the at least two second patterned assistant electrodes being disposed corresponding to part of the black matrix respectively, and the at least two first patterned assistant electrodes being electrically isolated from the at least two second patterned assistant electrodes;

forming a first transparent conductive layer on the side of the transparent substrate facing the thin film transistor substrate to cover the at least two first patterned assistant electrodes, the at least two second patterned assistant electrodes and the black matrix, and part of the transparent substrate; and

patterning the first transparent conductive layer to form at least two first transparent sensing pads and at least two second transparent sensing pads and at least one second bridge structure, the at least one first bridge structure electrically connecting to the at least two first transparent sensing pads, the at least one second bridge structure electrically connecting to the at least two second transparent sensing pads, the at least one second bridge structure being electrically isolated from the at least one first bridge structure, the at least two first transparent sensing pads being disposed on the at least two first patterned assistant electrodes and on the black matrix under the at least two first patterned assistant electrodes, the at least two second transparent sensing pads being disposed on the at least two second patterned assistant electrodes and on the black matrix under the at least two second patterned assistant electrodes, and the at least two first transparent sensing pads being electrically isolated from the at least two second transparent sensing pads.

8. The method of claim 7, further comprising:

forming a plurality of color filters on the at least two first transparent sensing pads and the at least two second transparent sensing pads;

forming a planarization layer on the color filters; and

forming a second transparent conductive layer on the planarization layer.

9. The method of claim 7, wherein after forming the at least one first bridge structure, the method further comprises:

forming at least one patterned insulating layer on the at least one first bridge structure, wherein the at least one second bridge structure crosses the at least one patterned insulating layer so as to electrically connect to the at least two second transparent sensing pads.

10. The method of claim 7, wherein after forming the at least one first bridge structure, the method further comprises:

forming an insulating layer covering the at least two first transparent sensing pads, the at least two second transparent sensing pads, the black matrix, part of the transparent substrate and the at least one first bridge structure, and the insulating layer having a plurality of openings to expose the at least two second transparent sensing pads partially, wherein the at least one second bridge structure connects electrically to the at least two second transparent sensing pads through the openings.

11. The method of claim 7, wherein the step of patterning the assistant electrode layer comprises forming at least one alignment mark.

12. The method of claim 7, wherein at least a part of the at least two first and the at least two second patterned assistant electrodes comprises a plurality of conductive strips, and the black matrix comprises a plurality of strip regions, and wherein the width of each of the conductive strips is substantially 6 micrometers smaller than that of each of the strip regions.