Touch panel and method of fabricating the same

• US 9,239,653 B2
• Filed: 08/06/2012
• Issued: 01/19/2016
• Est. Priority Date: 03/28/2012
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Chuang, Wen-Chi, Yeh, Chia-Chun, Huang, Yu-Ching
• Primary Examiner(s): Thompson, Timothy
• Assistant Examiner(s): Alonzo Miller, Rhadames J
• Application Number:
  US13/567,103
• Publication Number:
  US 20130257519A1
• Time in Patent Office: 1,261 Days
• Field of Search: 174/250, 174/257, 327/517, 427/97.1, 427/97.3, 216/13, 345/173
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• 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 3/0445 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 touch panel includes a substrate, a touch-sensing circuit, and fan-out traces. The substrate has a touch-sensing region and an adjoined peripheral region. The touch-sensing circuit is disposed on the touch-sensing region. The fan-out traces are disposed on the peripheral region and electrically connected to the touch-sensing circuit. Each fan-out trace includes a first conductive line, a first dielectric layer and a second conductive line. The first conductive line is disposed on the peripheral region. The first dielectric layer is disposed on the peripheral region to cover the first conductive line, and has at least one contact window located above the first conductive line. The second conductive line is disposed on the first dielectric layer, wherein the first and the second conductive line of the same fan-out trace have the same pattern and are electrically connected through the contact window.

Claims

1. A touch panel, comprising:

a substrate having a touch-sensing region and a peripheral region adjacent to the touch-sensing region;

a touch-sensing circuit disposed on the touch-sensing region of the substrate; and

a plurality of fan-out traces disposed on the peripheral region of the substrate and electrically connected to the touch-sensing circuit, and each of the fan-out traces comprising;

a first conductive line disposed on the peripheral region of the substrate;

a first dielectric layer disposed on the peripheral region of the substrate to cover the first conductive line, wherein the first dielectric layer has at least one contact window located above the first conductive line; and

a second conductive line disposed on the first dielectric layer, wherein the first conductive line and the second conductive line of a same fan-out trace are electrically connected to each other through the contact windows, and the first conductive line and the second conductive line which are electrically connected to each other substantially have a same pattern.

2. The touch panel as claimed in claim 1, wherein the touch-sensing circuit comprises:

a plurality of first sensing series electrically insulated from each other;

a plurality of second sensing series electrically insulated from each other; and

a second dielectric layer at least disposed at intersections of the first sensing series and the second sensing series, so that the first sensing series and the second sensing series are electrically insulated.

3. The touch panel as claimed in claim 2, wherein the first dielectric layer and the second dielectric layer are formed by a same material layer.

4. The touch panel as claimed in claim 2, wherein each of the first sensing series extends from the touch-sensing region to the peripheral region to cover a portion of the first conductive lines, and each of the second sensing series extends from the touch-sensing region to the peripheral region to cover a portion of the second conductive lines.

5. The touch panel as claimed in claim 1, further comprising a black matrix disposed on the peripheral region of the substrate, wherein the fan-out traces are disposed on the black matrix.

6. The touch panel as claimed in claim 5, further comprising a buffer layer disposed on the substrate, wherein the black matrix is disposed on the buffer layer.

7. The touch panel as claimed in claim 5, further comprising a third dielectric layer, wherein the third dielectric layer covers the substrate and the black matrix, and the first conductive lines are disposed on the third dielectric layer.

8. The touch panel as claimed in claim 1, further comprising a protective layer covering the touch-sensing circuit and the fan-out traces.

9. The touch panel as claimed in claim 1, wherein the first dielectric layer has a plurality of contact windows located above the first conductive lines to expose two ends of each of the first conductive lines.

10. A fabricating method of a touch panel, comprising:

providing a substrate, wherein the substrate has a touch sensing region and a peripheral region adjacent to the touch sensing region;

forming a plurality of first conductive lines on the peripheral region of the substrate;

forming a plurality of first sensing series electrically insulated from each other on the touch-sensing region of the substrate;

forming a dielectric layer on the peripheral region of the substrate to cover a portion of the first conductive lines, wherein the dielectric layer has at least one contact window located above the first conductive lines;

forming a second sensing series electrically insulated from each other on the touch-sensing region of the substrate, wherein the dielectric layer is at least disposed at intersections of the first sensing series and the second sensing series, so that the first sensing series and the second sensing series are electrically insulated; and

forming a plurality of second conductive lines on the dielectric layer, wherein the first conductive line and the second conductive line of a same fan-out trace are electrically connected to each other through the contact windows, and the first conductive line and the second conductive line which are electrically connected to each other substantially have a same pattern.

11. The fabricating method of a touch panel as claimed in claim 10, wherein the first conductive lines and the second conductive lines are respectively fabricated by a two-step photolithography and etching process, and the two-step photolithography and etching process uses a same photo-mask.

12. The fabricating method of a touch panel as claimed in claim 10, further comprising forming a black matrix on the peripheral region of the substrate, wherein the fan-out traces are disposed on the black matrix.

13. The fabricating method of a touch panel as claimed in claim 12, further comprising forming a buffer layer on the substrate, wherein the black matrix is disposed on the buffer layer.

14. The fabricating method of a touch panel as claimed in claim 10, further comprising forming a third dielectric layer, wherein the third dielectric layer covers the substrate and the black matrix, and the first conductive lines are disposed on the third dielectric layer.

15. The fabricating method of a touch panel as claimed in claim 10, further comprising forming a protective layer covering the touch-sensing circuit and the fan-out traces.

16. The fabricating method of a touch panel as claimed in claim 10, wherein the first dielectric layer has a plurality of contact windows located above the first conductive lines to expose two ends of each of the first conductive lines.