Counter electrode for electrochromic devices

• US 10,156,762 B2
• Filed: 11/20/2015
• Issued: 12/18/2018
• Est. Priority Date: 03/31/2009
• Status: Active Grant

• Current Assignee: View Incorporated
• Original Assignee: View Incorporated
• Inventors: Gillaspie, Dane, Kailasam, Sridhar K., Rozbicki, Robert T.
• Primary Examiner(s): PINKNEY, DAWAYNE
• Application Number:
  US15/527,194
• Publication Number:
  US 20170371221A1
• Time in Patent Office: 1,124 Days
• Field of Search: 359296, 359253-254, 359245-247, 359290-291, 359298, 359265-275, 359277, 359242, 349 33, 345 49, 345105, 345107, 430 31- 32
• CPC Class Codes: B23K 20/10 making use of vibrations, e.g. ultrasonic welding
• CPC Class Codes: C03C 17/3417 all coatings being oxide coatings
• CPC Class Codes: C03C 2217/94 Transparent conductive oxide layers [TCO] being part of a multilayer coating
• CPC Class Codes: C23C 10/28 using solids, e.g. powders, pastes
• CPC Class Codes: C23C 14/083 of refractory metals or yttrium
• CPC Class Codes: C23C 14/085 of iron group metals
• CPC Class Codes: C23C 14/185 by cathodic sputtering
• CPC Class Codes: C23C 14/3407 Cathode assembly for sputtering apparatus, e.g. Target
• CPC Class Codes: C23C 14/5806 Thermal treatment
• CPC Class Codes: C23C 14/5853 Oxidation
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/1523 comprising inorganic material
• CPC Class Codes: G02F 1/1525 characterised by a particular ion transporting layer, e.g. electrolyte
• CPC Class Codes: G02F 1/155 Electrodes
• CPC Class Codes: G02F 2001/1502 complementary cell
• CPC Class Codes: G02F 2001/1555 Counter electrode

Abstract

The embodiments herein relate to electrochromic stacks, electrochromic devices, and methods and apparatus for making such stacks and devices. In various embodiments, an anodically coloring layer in an electrochromic stack or device is fabricated to include nickel tungsten tantalum oxide (NiWTaO). This material is particularly beneficial in that it is very transparent in its clear state.

Claims

1. A method of fabricating an electrochromic stack, the method comprising:

forming a cathodically coloring layer comprising a cathodically coloring electrochromic material; and

forming an anodically coloring layer comprising nickel tungsten tantalum oxide.

2. The method of claim 1, wherein the nickel tungsten tantalum oxide has an atomic ratio of Ni:

(W+Ta) that is between about 1.5;

1 and 3;

1.

3. The method of claim 2, wherein the atomic ratio of Ni:

(W+Ta) in the nickel tungsten tantalum oxide is between about 1.5;

1 and 2.5;

1.

4. The method of claim 1, wherein the nickel tungsten tantalum oxide has an atomic ratio of W:

Ta that is between about 1;

1 and 2;

1.

5. The method of claim 1, wherein forming the anodically coloring layer comprises sputtering one or more sputter targets each comprising at least one metal selected from the group consisting of nickel, tungsten, and tantalum to form the nickel tungsten tantalum oxide.

6. The method of claim 1, wherein the anodically coloring layer is substantially amorphous.

7. The method of claim 1, wherein the cathodically coloring layer and the anodically coloring layer are formed in direct physical contact with one another, without a separate ion conductor layer deposited between them, and further comprising converting a portion of the cathodically coloring layer and/or a portion of the anodically coloring layer to form an ion conducting and electrically insulating interfacial region between the cathodically coloring and anodically coloring layers.

8. The method of claim 1, wherein the anodically coloring layer comprises two or more sub-layers that have different compositions and/or morphologies.

9. The method of claim 1, wherein the cathodically coloring electrochromic material comprises tungsten oxide.

10. The method of claim 1, wherein the cathodically coloring layer comprises a bilayer or a graded layer, and wherein a portion of the cathodically coloring layer is superstoichiometric with respect to oxygen.

11. An electrochromic device stack, comprising:

a cathodically coloring layer comprising a cathodically coloring material; and

an anodically coloring layer comprising nickel tungsten tantalum oxide.

12. The electrochromic device stack of claim 11, wherein the nickel tungsten tantalum oxide has an atomic ratio of Ni:

(W+Ta) that is between about 1.5;

1 and 3;

1.

13. The electrochromic device stack of claim 12, wherein the atomic ratio of Ni:

(W+Ta) in the nickel tungsten tantalum oxide is between about 1.5;

1 and 2.5;

1.

14. The electrochromic device stack of claim 11, wherein the nickel tungsten tantalum oxide has an atomic ratio of W:

Ta that is between about 1;

1 and 2;

1.

15. The electrochromic device stack of claim 11, wherein the anodically coloring layer is substantially amorphous.

16. The electrochromic device stack of claim 11, wherein the anodically coloring layer comprises two or more sub-layers having different compositions and/or morphologies.

17. The electrochromic device stack of claim 11, wherein the cathodically coloring material comprises tungsten oxide.

18. The electrochromic device stack of claim 11, wherein the cathodically coloring layer comprises a bilayer or a graded layer, and wherein a portion of the cathodically coloring layer is superstoichiometric with respect to oxygen.

19. A composition of matter comprising:

(a) nickel;

(b) tungsten;

(c) tantalum; and

(d) oxygen,

wherein the composition comprises an atomic ratio of Ni;

(W+Ta) that is between about 1.5;

1 and 3;

1, and

an atomic ratio of W;

Ta that is between about 0.1;

1 and 6;

1.

20. The composition of claim 19, wherein the atomic ratio of Ni:

(W+Ta) is between about 1.5;

1 and 2.5;

1.

21. The composition of claim 19, wherein the atomic ratio of W:

Ta is between about 1;

1 and 2;

1.

22. The composition of claim 19, wherein the composition is provided as an amorphous matrix with nanocrystals distributed throughout, wherein the nanocrystals have a mean diameter of about 50 nm or less.