Method for fabricating touch sensor panels

• US 8,388,852 B2
• Filed: 07/30/2010
• Issued: 03/05/2013
• Est. Priority Date: 07/30/2010
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Huang, Lili, Mohapatra, Siddharth, Zhong, John Z.
• Primary Examiner(s): Vinh, Lan
• Application Number:
  US12/848,049
• Publication Number:
  US 20120024816A1
• Time in Patent Office: 949 Days
• Field of Search: 216/24, 216/26, 216/40, 216/43, 216/95, 216/100, 216/13, 216/33, 438/717, 438/723, 438/725, 438/742
• US Class Current: 216/43
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/0445 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: H05K 2203/0571 Dual purpose resist, e.g. etch resist used as solder resist, solder resist used as plating resist
• CPC Class Codes: H05K 3/064 Photoresists
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

A method for fabricating a touch sensor panel is disclosed. The method includes providing a substrate for the touch sensor panel, depositing a conductive material layer on a top surface of the substrate, depositing a metal layer on top of the conductive material layer, affixing a resist to a first area of the metal layer, the resist also adapted to serve as a passivation layer during passivation, removing metal from the metal layer outside of the first area; and performing passivation on the substrate while leaving the affixed resist intact.

Claims

1. A method for fabricating a touch sensor panel, comprising:

providing a substrate for the touch sensor panel;

depositing a conductive material layer on a top surface of the substrate;

depositing a metal layer on top of the conductive material layer;

applying a temporary strip mask over a bonding area of the first area of the metal layer;

affixing a resist to a first area of the metal layer and the temporary strip mask, the resist also adapted to serve as a passivation layer during passivation;

removing metal from the metal layer outside of the first area; and

performing passivation on the substrate while leaving the affixed resist intact.

2. The method of claim 1, wherein the resist in a photoresist.

3. The method of claim 1, wherein the resist is a heat resist.

4. The method of claim 1, wherein the removing of metal from the metal layer is by photolithography.

5. The method of claim 1, wherein the removing of metal from the metal layer is by etching.

6. The method of claim 1, wherein the substrate is polyethylene terephthalate (PET).

7. The method of claim 1, wherein the substrate is polycarbonate (PC).

8. The method of claim 1, further comprising:

removing the temporary strip mask and the resist affixed thereto over the bonding area to expose the bonding area for flex circuit bonding.

9. The method of claim 1, further comprising bonding a flex circuit to the bonding area.

10. The method of claim 1, wherein the conductive material layer and the metal layer are deposited simultaneously.

11. The method of claim 1, wherein the metal layer is copper.

12. The method of claim 1, wherein the conductive material layer is ITO.

13. The method of claim 1, wherein the first area of the metal layer excludes a bonding area reserved for flex circuit bonding.

14. The method of claim 13, wherein the bonding area is located on an extended area of the touch sensor panel.

15. The method of claim 13, further comprising bonding a flex circuit to the bonding area.

16. The method of claim 1, further comprising patterning the conductive material layer and the metal layer to form drive and sense elements of the touch sensor panel.

17. The method of claim 16, wherein the patterning uses dry film resist (DFR).

18. The method of claim 16, wherein the patterning is by etching.

19. A method for fabricating a touch sensor panel, comprising:

forming a plurality of traces on a substrate;

applying a temporary strip mask over a bonding area of a first portion of the traces;

depositing a first material over a first portion of the traces and the temporary strip mask, the first material adapted to serve as both a photoresist and a passivation layer;

removing those traces not covered by the first material; and

passivating the substrate while leaving the deposited first material intact.

20. The method of claim 19, wherein the removing of the traces is by lithography.

21. The method of claim 19, wherein the removing of the traces is by etching.

22. The method of claim 19, further comprising:

removing the temporary strip mask and the first material affixed thereto over the bonding area to expose the bonding area for flex circuit bonding.

23. The method of claim 19, wherein the traces are made of copper.

24. The method of claim 19, wherein the first portion of the traces excludes a bonding area reserved for flex circuit bonding.

25. The method of claim 24, wherein the bonding area is located on an extended area of the touch sensor panel.