Transparent conductive coating for capacitive touch panel and method of making same

• US 10,540,047 B2
• Filed: 04/01/2019
• Issued: 01/21/2020
• Est. Priority Date: 11/27/2012
• Status: Active Grant

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Inventors: Krasnov, Alexey, Den Boer, Willem
• Primary Examiner(s): Shankar, Vijay
• Assistant Examiner(s): Almeida, Cory A
• Application Number:
  US16/371,190
• Publication Number:
  US 20190227653A1
• Time in Patent Office: 295 Days
• CPC Class Codes: C03C 17/3626 one layer at least containing a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/3644 the metal being silver
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• 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 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• 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 multi-layer conductive coating is substantially transparent to visible light, contains at least one conductive layer comprising silver that is sandwiched between at least a pair of dielectric layers, and may be used as an electrode and/or conductive trace in a capacitive touch panel. The multi-layer conductive coating may contain a dielectric layer(s), and may be used in applications such as capacitive touch panels for controlling showers, appliances, vending machines, electronics, electronic devices, and/or the like. In certain example embodiments, different electrodes of the touch panel may be formed by different silver based layers of the same or different multi-layer coatings. In patterning the electrodes, different laser scribing wavelengths may be used to pattern different respective silver based layers, of the same or different multi-layer coating(s), in certain example embodiments.

Claims

1. A capacitive touch panel, comprising:

a substrate;

a multi-layer transparent conductive coating supported by the substrate, the multi-layer transparent conductive coating including a first conductive layer, a first dielectric layer comprising silicon nitride located between at least the substrate and the first conductive layer, and a second dielectric layer comprising one or more of;

zirconium oxide, silicon nitride, and tin oxide, located over at least the first conductive layer;

each of said layers of the multi-layer transparent conductive coating being patterned in substantially the same shape as viewed from above;

at least one electrode configured for allowing touch position to be determined, and comprising the multi-layer transparent conductive coating; and

a processor configured for determining touch position on the touch panel.

2. The capacitive touch panel of claim 1, wherein the at least one electrode comprises:

a first set of electrodes oriented substantially perpendicular to electrodes of a second set of electrodes, as viewed from above.

3. The capacitive touch panel of claim 2, wherein the electrodes in the first set are receive electrodes, and the electrodes in the second set are transmit electrodes.

4. The capacitive touch panel of claim 3, wherein the transmit electrodes have a higher sheet resistance (RS) than do the receive electrodes, and wherein the transmit electrodes have a sheet resistance (Rs) at least 1 ohm/square higher than a sheet resistance of the receive electrodes.

5. The capacitive touch panel of claim 4, wherein the transmit electrodes have a sheet resistance (Rs) at least 5 ohms/square higher than a sheet resistance of the receive electrodes.

6. The capacitive touch panel of claim 1, wherein the conductive layer comprises silver and is doped.

7. The capacitive touch panel of claim 6, wherein the conductive layer comprising silver is doped with from about 0.05 to 3.0% (wt. %) of one or more of Zn, Pt, Pd, Ti, and Al.

8. The capacitive touch panel of claim 6, wherein the conductive layer comprising silver is doped with from about 0.1 to 2.0% (wt. %) of one or more of Zn, Pt, Pd, Ti, and Al.

9. The capacitive touch panel of claim 1, wherein the conductive layer comprises Ni and/or Cr.

10. The capacitive touch panel of claim 1, wherein the transparent conductive coating has a sheet resistance of less than or equal to about 40 ohms/square.

11. The capacitive touch panel of claim 1, wherein the second dielectric layer comprises silicon nitride.