Transparent conductive coating for capacitive touch panel or the like

• US 9,557,871 B2
• Filed: 04/08/2015
• Issued: 01/31/2017
• Est. Priority Date: 04/08/2015
• Status: Expired due to Fees

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Industries Corporation (KOCH Industries Incorporated)
• Inventors: Weng, Jian-gang, den Boer, Willem
• Primary Examiner(s): Cheng, Joe H
• Application Number:
  US14/681,266
• Publication Number:
  US 20160299596A1
• Time in Patent Office: 664 Days
• US Class Current: 1/1
• CPC Class Codes: C03C 17/3618 Coatings of type glass/inorganic compound/other inorganic layers, at least one layer being metallic
• CPC Class Codes: C03C 17/3626 one layer at least containing a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/3642 the multilayer coating containing a metal layer
• CPC Class Codes: C03C 17/3644 the metal being silver
• CPC Class Codes: C03C 17/3655 the multilayer coating containing at least one conducting layer
• CPC Class Codes: C03C 17/3657 the multilayer coating having optical properties
• CPC Class Codes: C03C 17/3671 specially adapted for use as electrodes
• CPC Class Codes: C03C 2217/211 SnO2
• CPC Class Codes: C03C 2217/212 TiO2
• CPC Class Codes: C03C 2217/216 ZnO
• CPC Class Codes: C03C 2217/256 Ag
• CPC Class Codes: C03C 2217/281 Nitrides
• CPC Class Codes: C03C 2218/154 by sputtering
• CPC Class Codes: C23C 14/34 Sputtering
• CPC Class Codes: G02B 1/115 Multilayers
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

This invention relates to a transparent conductive coating that is substantially transparent to visible light and is designed to have a visible reflectance which more closely matches that the visible reflectance of the underlying substrate. In certain example embodiments, the transparent conductive multilayer coating includes a silver layer(s) and may be used as an electrode(s) in a capacitive touch panel so as to provide for an electrode(s) transparent to visible light but without much visibility due to the substantial matching visible reflection design.

Claims

1. A capacitive touch panel, comprising:

a substrate;

a multi-layer transparent conductive coating supported by the substrate,

wherein the multi-layer transparent conductive coating comprises at least one conductive layer comprising silver located between at least a first dielectric layer and a second dielectric layer,

wherein the multi-layer transparent conductive coating, comprising at least the conductive layer comprising silver located between at least the first dielectric layer and the second dielectric layer is patterned into a plurality of electrodes for the touch panel;

a processor which measures capacitance between electrodes in detecting touch position on the touch panel,

wherein the electrodes formed from the multi-layer transparent conductive coating are formed substantially in a common plane substantially parallel to the substrate, and

wherein there is no more than a 2.0 difference at 600 nm between (a) a glass side visible reflectance percentage of the multi-layer transparent conductive coating on the substrate in areas where the coating is present, and (b) a visible reflectance percentage of the substrate in at least some areas where the multi-layer transparent conductive coating is not present.

2. The capacitive touch panel of claim 1, wherein the substrate is a glass substrate.

3. The capacitive touch panel of claim 1, wherein a glass substrate coated with an antireflective (AR) coating makes up said substrate.

4. The capacitive touch panel of claim 1, wherein there is no more than a 1.5 difference at 600 nm between (a) a glass side visible reflectance percentage of the multi-layer transparent conductive coating on the substrate in areas where the coating is present, and (b) a visible reflectance percentage of the substrate in at least some areas where the multi-layer transparent conductive coating is not present.

5. The capacitive touch panel of claim 1, wherein there is no more than a 1.0 difference at 600 nm between (a) a glass side visible reflectance percentage of the multi-layer transparent conductive coating on the substrate in areas where the coating is present, and (b) a visible reflectance percentage of the substrate in at least some areas where the multi-layer transparent conductive coating is not present.

6. The capacitive touch panel of claim 1, wherein the first dielectric layer comprises titanium oxide.

7. The capacitive touch panel of claim 1, wherein the second dielectric layer comprises tin oxide.

8. The capacitive touch panel of claim 1, wherein the multi-layer transparent conductive coating comprises, moving away from the substrate:

a dielectric layer comprising titanium oxide;

another dielectric layer comprising zinc oxide;

a conductive layer comprising silver directly contacting the dielectric layer comprising zinc oxide;

a contact layer over and contacting the conductive layer comprising silver;

another dielectric layer comprising titanium oxide;

another dielectric layer comprising tin oxide; and

another dielectric layer comprising silicon nitride.

9. The capacitive touch panel of claim 8, wherein the first dielectric layer comprising titanium oxide has a thickness of from about 130-185 angstroms.

10. The capacitive touch panel of claim 8, wherein the first dielectric layer comprising titanium oxide has a thickness of from about 150-185 angstroms.

11. The capacitive touch panel of claim 8, wherein the dielectric layer comprising silicon nitride has a thickness of from about 300-400 angstroms.

12. The capacitive touch panel of claim 8, wherein the dielectric layer comprising silicon nitride has a thickness of from about 300-320 angstroms.

13. The capacitive touch panel of claim 1, wherein the multi-layer transparent conductive coating comprises, moving away from the substrate:

a dielectric layer comprising silicon nitride;

a dielectric layer comprising silicon oxide;

a dielectric layer comprising titanium oxide;

another dielectric layer comprising zinc oxide;

a conductive layer comprising silver directly contacting the dielectric layer comprising zinc oxide;

a contact layer over and contacting the conductive layer comprising silver;

another dielectric layer comprising titanium oxide;

another dielectric layer comprising tin oxide; and

another dielectric layer comprising silicon nitride.

14. The capacitive touch panel of claim 1, wherein the multi-layer transparent conductive coating comprises, moving away from the substrate:

a dielectric layer comprising zinc oxide;

a conductive layer comprising silver directly contacting the dielectric layer comprising zinc oxide;

a contact layer over and contacting the conductive layer comprising silver;

a dielectric layer comprising silicon nitride.

15. The capacitive touch panel of claim 14, wherein the contact layer comprises an oxide of Ni and/or Cr.

16. The capacitive touch panel of claim 1, wherein the multi-layer transparent conductive coating has a sheet resistance of less than or equal to about 15 ohms/square.

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

18. The capacitive touch panel of claim 1, wherein the multi-layer transparent conductive coating has a sheet resistance of less than or equal to about 5 ohms/square.

19. An assembly comprising the capacitive touch panel of claim 1 coupled to a liquid crystal panel, the liquid crystal panel including a liquid crystal layer between at least a pair of substrates, and wherein the multi-layer transparent conductive coating is provided between said substrate supporting the multi-layer transparent conductive coating and the liquid crystal panel, and wherein the multi-layer transparent conductive coating is adjacent an air gap that is provided between the liquid crystal panel and the multi-layer transparent conductive coating.

20. A method of manufacturing a touch panel comprising a glass substrate and a signal processor, the method comprising:

sputter-depositing a multi-layer silver-inclusive transparent conductive coating on the substrate and patterning the multi-layer silver-inclusive transparent conductive coating to form a plurality of conductive electrodes and a plurality of conductive traces,

wherein the plurality of electrodes and the plurality of traces are in a plane substantially parallel to the substrate, wherein each of the electrodes is electrically connected to the signal processor by at least one of the traces, and

wherein there is no more than a 2.0 difference in a range from 550-600 nm between (a) a glass side visible reflectance percentage and/or film side visible reflectance percentage of the multi-layer transparent conductive coating on the substrate in areas where the coating is present, and (b) a visible reflectance percentage of the substrate in at least some areas where the multi-layer transparent conductive coating is not present.

21. The method of claim 20, wherein a glass substrate coated with an antireflective (AR) coating makes up the substrate.

22. The method of claim 20, wherein there is no more than a 1.0 difference in a range from 550-600 nm between (a) a glass side and/or film side visible reflectance percentage of the multi-layer transparent conductive coating on the substrate in areas where the coating is present, and (b) a visible reflectance percentage of the substrate in at least some areas where the multi-layer transparent conductive coating is not present.

23. The method of claim 20, providing a display panel that is coupled to the substrate with an air gap therebetween, and wherein the multi-layer transparent conductive coating is adjacent the air gap.

24. A coated article comprising a multi-layer coating on a glass substrate, the multi-layer coating comprising, moving away from the substrate:

a first dielectric layer comprising titanium oxide having a thickness of from 150-185 angstroms;

another dielectric layer comprising zinc oxide;

a conductive layer comprising silver directly contacting the dielectric layer comprising zinc oxide;

a contact layer over and contacting the conductive layer comprising silver;

another dielectric layer comprising titanium oxide;

another dielectric layer comprising tin oxide; and

another dielectric layer comprising silicon nitride having a thickness of from about 300-400 angstroms;

wherein there is no more than a 2.0 difference in a range from 550-600 nm between (a) a glass side visible reflectance percentage and/or film side visible reflectance percentage of the coating on the glass substrate in an area where the coating is present on the glass substrate, and (b) a visible reflectance percentage of the glass substrate itself absent the coating.

25. An assembly comprising the coated article of claim 24 coupled to a display panel with an air gap therebetween, wherein the multi-layer coating is adjacent the air gap so as to be located between the substrate and the air gap.

26. A coated article comprising a multi-layer coating on glass substrate, the multi-layer coating comprising, moving away from the glass substrate:

(i) an antireflective (AR) portion comprising;

(a) a first high refractive index dielectric layer;

(b) a first low refractive index dielectric layer;

(c) a second high refractive index dielectric layer;

(d) a second low refractive index dielectric layer, wherein the second high refractive index layer is located between and contacting the first and second low refractive index dielectric layers, and the first low refractive index dielectric layer is located between and contacting the first and second high refractive index layers;

the first and second high refractive index dielectric layers having a refractive index (n) of at least about 2.15 at 550 nm;

the first and second low refractive index dielectric layers having a refractive index (n) of no greater than about 1.7 at 550 nm; and

(e) a dielectric layer comprising metal oxide;

(ii) a portion including a conductive layer comprising;

(a) a dielectric layer comprising silicon nitride;

(b) a dielectric layer comprising zinc oxide;

(c) a conductive layer comprising silver directly contacting the dielectric layer comprising zinc oxide;

(d) a contact layer over and contacting the conductive layer comprising silver; and

(e) a dielectric layer comprising silicon nitride.

27. The coated article of claim 26, wherein the dielectric layer comprising metal oxide comprises an oxide of zirconium.

28. The coated article of claim 26, wherein the first and second low refractive index dielectric layers comprise oxide of silicon.

29. The coated article of claim 26, wherein the first and second high refractive index dielectric layers comprise an oxide of titanium and/or niobium.

30. The coated article of claim 26, wherein there is no more than a 2.0 difference in a range from 550-600 nm between (a) a glass side visible reflectance percentage of the coating on the glass in an area where the coating is present on the glass, and (b) a glass side visible reflectance percentage of the glass in an area where only the antireflective (AR) portion (i), but not the portion (ii), is present on the glass.

31. The coated article of claim 26, wherein there is no more than a 1.0 difference in a range from 550-600 nm between (a) a glass side visible reflectance percentage of the coating on the glass in an area where the coating is present on the glass, and (b) a glass side visible reflectance percentage of the glass in an area where only the antireflective (AR) portion (i), but not the portion (ii), is present on the glass.

32. An assembly comprising the coated article of claim 26 coupled to a display panel with an air gap therebetween, wherein the coating is adjacent the air gap so as to be located between the glass and the air gap.