Corrosion mitigation for metal traces

Patent metadata

Field	Value
Publication number	US-10048814-B2
Application number	US-201514960202-A
Country	US
Kind code	B2
Filing date	Dec 4, 2015
Priority date	Sep 10, 2012
Publication date	Aug 14, 2018
Grant date	Aug 14, 2018

Abstract

Processes for manufacturing touch sensors with one or more guard traces to reduce the effect of moisture damage are provided. One example process can include forming one or more guard traces between an edge of the touch sensor and the metal traces that route the drive and sense lines to bond pads. The one or more guard traces can be uncoupled from the drive lines and sense lines to protect the inner metal traces from moisture damage. In some examples, ends of the one or more guard traces can be coupled to ground by copper. In other examples, ends of the one or more guard traces can be coupled to ground by indium tin oxide or the one or more guard traces can be coupled to ground by a strip of indium tin oxide. In yet other examples, the guard trace can be floating (e.g., not coupled to ground).

First claim

What is claimed is:

1. A touch sensor panel comprising:
a plurality of touch nodes, each touch node configured for forming a self-capacitance to ground;
one or more bond pads;
a plurality of routing traces that electrically couples the plurality of touch nodes to the one or more bond pads and circuitry; and
a trace positioned between edges of the touch sensor panel and the plurality of routing traces, the trace configured to at least one of block, absorb, and detect moisture.

2. The touch sensor panel of claim 1 , wherein the trace is electrically decoupled from the plurality of touch nodes.

3. The touch sensor panel of claim 1 , wherein the trace includes copper.

4. The touch sensor panel of claim 1 , wherein the trace includes indium tin oxide (ITO).

5. The touch sensor panel of claim 1 , further comprising:
circuitry coupled to the trace and configured to detect an open circuit.

6. The touch sensor panel of claim 1 , wherein the circuitry is configured to stimulate the plurality of touch nodes or sense a capacitance from the plurality of touch nodes.

7. The touch sensor panel of claim 1 , wherein a width of the trace is greater or less than a width of the plurality of routing traces.

8. The touch sensor panel of claim 1 , further comprising:
a second trace configured to at least one of block, absorb, and detect moisture.

9. A method of manufacturing a touch sensor panel, the method comprising:
forming a plurality of touch nodes, each touch node configured to form a self-capacitance to ground;
forming a plurality of routing traces electrically coupled to circuitry; and
forming and locating a trace between edges of the touch sensor panel and the plurality of routing traces, the trace configured to at least one of block, absorb, and detect moisture.

10. The method of claim 9 , wherein the trace is formed on a same layer as the plurality of touch nodes and the plurality of routing traces.

Assignees

• Apple Inc

Inventors

• Mohapatra Siddharth
• Kang Sunggu
• Zhong John Z

Classifications

• Y10T29/49105

  Switch making · CPC title

• H01H11/04

  of switch contacts · CPC title

• G06F3/0416 Primary

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F2203/04103

  Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices · CPC title

• G06F2203/04107

  Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds · CPC title