Method of forming a color filter touch sensing substrate

• US 8,052,498 B2
• Filed: 04/15/2009
• Issued: 11/08/2011
• 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:
  US12/423,814
• Publication Number:
  US 20100136868A1
• Time in Patent Office: 937 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 first transparent conductive layer and an assistant electrode layer sequentially on a side of the transparent substrate facing the thin film transistor substrate;

patterning the first transparent conductive layer and the assistant electrode layer, wherein the first transparent conductive layer after patterning forms at least two first transparent sensing pads and at least two second transparent sensing pads, the assistant electrode layer after patterning forms at least two first patterned assistant electrodes and at least two second patterned assistant electrodes, the at least two first transparent sensing pads are electrically isolated from the at least two second transparent sensing pads, and the at least two first patterned assistant electrodes are electrically connected to and contact with the at least two first transparent sensing pads, the least two second patterned assistant electrodes are electrically connected to and contact with the at least two second transparent sensing pads, and the at least two first patterned assistant electrodes are electrically isolated from the at least two second patterned assistant electrodes; and

forming a black matrix on the side of the transparent substrate facing the thin film transistor substrate to cover the at least two first transparent sensing pads partially, the at least two second transparent sensing pads partially, the at least two first patterned assistant electrodes partially, the at least two second patterned assistant electrodes partially, and the transparent substrate partially, wherein the black matrix is formed by insulating materials.

2. The method of claim 1, further comprising:

forming a plurality of color filters on the black matrix;

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 the step of patterning the first transparent conductive layer and the assistant electrode layer comprises performing an exposure process by utilizing a graytone mask, a halftone mask, or a phase shift mask.

4. The method of claim 1, wherein the step of patterning the first transparent conductive layer and the assistant electrode layer comprises performing a plurality of exposure processes by utilizing a plurality of masks.

5. The method of claim 1, wherein the step of patterning the first transparent conductive layer and the assistant electrode layer comprises forming at least one first bridge structure, wherein the at least one first bridge structure electrically connected to the least two first transparent sensing pads.

6. The method of claim 5, wherein after the step of forming the at least one bridge substrate, the method further comprises:

forming at least one patterned insulating layer disposed on the at least one first bridge structure; and

forming at least one second bridge structure crossing the at least one insulating layer so as to electrically connect to the at least two second transparent sensing pads.

7. The method of claim 5, wherein after the step of forming the at least one bridge substrate, 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 at least one first bridge structure, the at least two first patterned assistant electrodes and the at least two second patterned assistant electrodes, the insulating layer having a plurality of openings to expose the at least two second transparent sensing pads partially; and

forming at least one second bridge structure, the at least one second bridge structure connecting electrically to the at least two second transparent sensing pads through the openings.

8. The method of claim 1, wherein the step of patterning the first transparent conductive layer and the assistant electrode layer comprises forming at least one alignment mark.