Transparent electrode-equipped substrate and method for producing transparent electrode-equipped substrate

• US 10,173,393 B2
• Filed: 03/18/2016
• Issued: 01/08/2019
• Est. Priority Date: 03/24/2015
• Status: Active Grant

• Current Assignee: Kaneka Corporation
• Original Assignee: Kaneka Corporation
• Inventors: Hayakawa, Hironori, Omoto, Shinya, Kuchiyama, Takashi
• Primary Examiner(s): Thompson, Timothy J
• Assistant Examiner(s): Miller, Rhadames Alonzo
• Application Number:
  US15/556,895
• Publication Number:
  US 20180194105A1
• Time in Patent Office: 1,026 Days
• CPC Class Codes: C23C 14/08 Oxides C23C14/10 takes precedence
• CPC Class Codes: C23C 14/086 of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: C23C 14/34 Sputtering
• CPC Class Codes: C23C 14/562 for coating elongated substrates
• CPC Class Codes: C23C 14/58 After-treatment
• CPC Class Codes: C23C 14/5806 Thermal treatment
• CPC Class Codes: C23C 14/5826 Treatment with charged particles C23C14/582 takes precedence
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: H01B 5/14 comprising conductive layers or films on insulating-supports

Abstract

A transparent electrode-equipped substrate includes a metal oxide transparent electrode layer on a transparent substrate. The average maximum curvature Ssc of the surface of the transparent electrode layer is preferably 5.4×10⁻⁴ nm⁻¹ or less. For example, if the transparent electrode layer is subjected to a surface treatment by low discharge-power sputtering after deposition, the Ssc of the transparent electrode layer can be reduced. This transparent electrode-equipped substrate excels in close adhesion between the transparent electrode layer and a lead-out wiring line disposed on the transparent electrode layer. The transparent electrode layer is obtained by, for example, performing a transparent electrode deposition step of through the application of a first discharge power and then performing a surface treatment step through the application of a second discharge power.

Claims

1. A substrate with a transparent electrode, comprising:

a transparent substrate; and

a transparent electrode layer comprising a metal oxide on the transparent substrate,

wherein a surface of the transparent electrode layer includes a plurality of protrusions, an average maximum curvature Ssc of the surface of the transparent electrode layer is 5.4×

10<sup>−

4</sup> nm<sup>−

1</sup> or less, and the average maximum curvature Ssc is calculated from a following equation;

2. The substrate with the transparent electrode according to claim 1, wherein the average maximum curvature Ssc of the surface of the transparent electrode layer is 2.5×

10<sup>−

4</sup> nm<sup>−

1</sup> or more and 5.0×

10<sup>−

4</sup> nm<sup>−

1</sup> or less.

3. The substrate with the transparent electrode according to claim 1, wherein the transparent substrate is a transparent film.

4. The substrate with the transparent electrode according to claim 1, further comprising a metallic extraction electrode on the transparent electrode layer.

6. A method for producing the substrate with the transparent electrode according to claim 1, the method comprising:

a transparent electrode deposition step of applying a first discharge power x₁ to a first sputtering target to deposit a transparent electrode layer at a deposition rate y₁; and

a surface treatment step of applying a second discharge power x₂ to a second sputtering target to surface-treat the transparent electrode layer at a deposition rate y₂,

wherein a ratio k₁=y₁/x₁ and a ratio k₂=y₂/x₂ satisfy a relationship of k₂≤

0.85k₁, where k₁ is a ratio between the discharge power and the deposition rate in the transparent electrode deposition step, and k₂ is a ratio between the discharge power and the deposition rate in the surface treatment step.

14. The substrate with the transparent electrode according to claim 1, wherein the metal oxide includes one or more of indium oxide, zinc oxide or tin oxide.

15. The substrate with the transparent electrode according to claim 14, wherein indium oxide includes indium tin oxide (ITO).

16. The substrate with the transparent electrode according to claim 3, wherein the thickness of the transparent film is 0.01 mm or more and 0.4 mm or less.

17. The substrate with the transparent electrode according to claim 1, wherein the transparent electrode layer is formed one or both of surfaces of the transparent substrate.

19. The substrate with the transparent electrode according to claim 1, further comprising one or more of a functional layer between the transparent substrate and the transparent electrode layer.

20. The substrate with the transparent electrode according to claim 19, wherein the functional layer includes any of an optical optimizing layer, an anti-reflection layer, an anti-glare layer, an easily adhesive layer, a stress buffer layer, a hard coat layer, a slippery layer, an antistatic layer, a crystallization acceleration layer, a crystallization rate controlling layer, and a durability improvement layer.

5. A method for producing a substrate with the transparent electrode comprising a transparent electrode layer comprising a metal oxide provided on a transparent substrate, the method comprising:

a transparent electrode deposition step of applying a first discharge power x₁ to a first sputtering target to deposit a transparent electrode layer at a deposition rate y₁; and

a surface treatment step of applying a second discharge power x₂ to a second sputtering target to surface-treat the transparent electrode layer at a deposition rate y₂,

wherein a ratio k₁=y₁/x₁ and a ratio k₂=y₂/x₂ satisfy a relationship of k₂≤

0.85k₁, where k₁ is a ratio between the discharge power and the deposition rate in the transparent electrode deposition step, and k₂ is a ratio between the discharge power and the deposition rate in the surface treatment step.

7. The method according to claim 5, wherein k₂≤

0.8k₁ is satisfied.

8. The method according to claim 5, wherein the surface treatment step further comprises forming a plurality of protrusions on a surface of the transparent electrode layer, an average maximum curvature Ssc₀ of the surface of the transparent electrode layer after the transparent electrode deposition step and before the surface treatment step is 5.5×

10<sup>−

4</sup> nm<sup>−

1</sup> or more, and the average maximum curvature Ssc is calculated from a following equation;

9. The method according to claim 5, wherein

a difference Ssc₀−

Ssc₁ is 5×

10<sup>−

5</sup> nm<sup>−

1</sup> or more, where

an average maximum curvature Ssc is calculated from a following equation;

10. The method according to claim 5, wherein

in each of the transparent electrode deposition step and the surface treatment step, sputtering is performed while an inert gas and oxygen are introduced, and

an oxygen partial pressure in a chamber during the surface treatment step is preferably larger than an oxygen partial pressure in a chamber during the transparent electrode deposition step.

11. The method according to claim 5, wherein

the first sputtering target used in the surface treatment step has a composition identical to a composition of the second sputtering target used in the transparent electrode deposition step.

12. The method according to claim 5, further comprising

a heating step after the surface treatment step, to crystallize the transparent electrode layer.

13. The method according to claim 5, further comprising

an extraction electrode forming step to form a metallic extraction electrode on the transparent electrode layer after the surface treatment step.

18. The method according to claim 5, wherein a discharge voltage during the surface treatment step is 400 V or less.