Method of making transparent conductors on a substrate

Patent metadata

Field	Value
Publication number	US-10831233-B2
Application number	US-201916281274-A
Country	US
Kind code	B2
Filing date	Feb 21, 2019
Priority date	Dec 7, 2012
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

A method of patterning a conductive layer to form transparent electrical conductors that does not require etching is disclosed. The method includes peeling a strippable polymer layer from a substrate coated with the conductive layer to pattern the conductive layer. In some embodiments, a resist matrix material is patterned over the conductive layer to prevent removal of the conductive layer beneath the resist matrix material. In other embodiments, a liner having a pressure sensitive adhesive surface is brought into contact with the patterned strippable polymer material to remove both the patterned strippable polymer material and the conductive layer beneath it.

First claim

The invention claimed is:

1. A method of patterning a conductive layer on a substrate, comprising:
coating a substrate with a conductive layer wherein the conductive layer comprises nanowires;
applying a pattern on the conductive layer with a resist matrix material to generate on the substrate one or more first regions of exposed conductive layer and one or more second regions of resist matrix material, wherein the resist matrix material contains an ultraviolet curable material;
hardening or curing the resist matrix material by ultraviolet irradiation;
over coating the pattern with a strippable polymer layer;
hardening or curing the strippable polymer layer;
peeling the strippable polymer layer from the substrate, removing the exposed conductive layer from the substrate in the one or more first regions of the substrate, and thereby forming a patterned conductive layer on the substrate.

2. The method according to claim 1 wherein over coating the pattern with the strippable polymer layer comprises over coating the one or more first regions and the one or more second regions with a strippable polymer layer-forming liquid, optionally wherein the strippable polymer layer-forming liquid exhibits a yield stress.

3. The method according to claim 1 , wherein the strippable polymer layer-forming liquid contacts between 50% to 99% of the exposed conductive layer in the one or more first regions.

4. The method according to claim 2 , wherein the strippable polymer layer-forming liquid is selected from the group consisting of a polymer solution, monomer, monomer solution, and polymer melt.

5. The method according to claim 2 , wherein the strippable polymer layer-forming liquid comprises a polymer solution and over coating includes slot coating, roll coating, flood coating, notch bar coating, or spraying.

6. The method according to claim 2 , wherein the strippable polymer layer-forming liquid exhibits a viscosity between 10 and 2,500 cps (0.01 and 2.5 Pa-s).

7. The method according to claim 2 , wherein the strippable polymer layer-forming liquid comprises PVA.

8. The method according to claim 2 , wherein the strippable polymer layer-forming liquid comprises a polymer melt and over coating includes thermal compression lamination, optionally wherein the strippable polymer layer-forming liquid exhibits a viscosity of between 10,000 and 100,000,000 cps (between 10 Pa-s and 100 kPa s).

9. The method according to claim 2 , wherein the strippable polymer layer-forming liquid exhibits a viscosity of between 10,000 and 100,000,000 cps (between 10 Pa-s and 100 kPa-s).

10. The method according to claim 2 , wherein the strippable polymer layer-forming liquid exhibits a yield stress.

11. The method according to claim 10 , wherein the strippable polymer layer-forming liquid exhibits a yield stress less than 100 Pa.

12. The method according to claim 2 , wherein the strippable polymer layer-forming liquid is deposited in a pattern over the first and second regions.

13. The method according to claim 2 , wherein the patterned strippable polymer layer-forming liquid is deposited using flexographic, gravure, ink-jet, or screen printing.

14. The method according to claim 2 , wherein the patterned strippable polymer layer-forming liquid covers between 50% and 99% of the first and second regions.

15. The method according to claim 1 wherein the resist matrix material contains an ultraviolet curable material.

16. The method according to claim 1 wherein the strippable polymer layer is from 2 μm to 100 μm thick.

17. The method according to claim 1 comprising applying an optically clear overlayer over the patterned resist matrix material after removing the strippable polymer layer.

18. The method according to claim 1 wherein the resist matrix material comprises a thickness between 50 nanometers and 50 micrometers.

19. The method according to claim 1 wherein the resist matrix material comprises an index of refraction of between 1.40-1.70.

20. The method of claim 1 , further comprising coating a lead-forming conductive layer over at least one portion of the patterned conductive layer.

21. The method of claim 20 , wherein the step of coating the lead-forming conductive layer occurs after the peeling the strippable polymer layer from the substrate.

22. The method of claim 20 , wherein the pattern of the resist matrix material includes interconnect pads, and wherein the lead forming conductive layer is coated above the interconnect pads with the lead-forming conductive layer contacting the patterned conductive layer along its exposed perimeter.

23. The method according to claim 22 , wherein the interconnect pads are patterned so as increase the length of the exposed perimeter.

24. The method according to claim 23 , wherein at least one of a void space or a corrugated outer margin is used to increase the length of the exposed perimeter.

25. The method of claim 20 , wherein the lead-forming conductive layer is an ink comprising silver particles.

Assignees

• 3M Innovative Properties Co

Inventors

• Dodds Shawn C
• Stay Matthew S
• Pekurovsky Mikhail L
• Frey Matthew H
• Pellerite Mark J
• Baetzold John P

Classifications

• G06F3/041 Primary

  Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means · CPC title

• Y10S977/887

  Nanoimprint lithography, i.e. nanostamp · CPC title

• B82Y15/00

  Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors · CPC title

• G06F2203/04112

  Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material · CPC title

• G06F1/16 Primary

  Constructional details or arrangements · CPC title