Scratch resistant flexible transparent electrodes and methods for fabricating ultrathin metal films as electrodes

Patent metadata

Field	Value
Publication number	US-10319489-B2
Application number	US-201615547033-A
Country	US
Kind code	B2
Filing date	Feb 10, 2016
Priority date	Feb 10, 2015
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

Systems and methods of fabricating electrodes, including thin metallic films, include depositing a first metallic layer on a substrate and passivating the deposited layer. The processes of deposition and passivation may be done sequentially. In some embodiments, a plurality of substrates may be coated with a metallic layer and further processed at a later time, including passivation and disposal of additional layers as discussed herein.

First claim

What is claimed is:

1. A method of fabricating an electrode comprising: depositing a first metallic layer in contact with a substrate, wherein the substrate comprises glass, silicon, or a polymer; passivating the first metallic layer via exposure to air or oxygen gas to form a passivated first layer; depositing a second metallic layer in contact with the passivated first layer; and passivating the second metallic layer via exposure to air or oxygen gas, wherein each of the first and the second metallic layers comprises silver (Ag), copper (Cu), aluminum (Al), or a combination thereof, is continuous, and comprises a plurality of grains, wherein an average diameter of the plurality of grains is less than about 50 nm and wherein the electrode comprises an optical transmittance between 40% to about 89%.

2. The method of claim 1 , wherein the substrate comprises polyethylene terephthalate or polydimethylsiloxane (PDMS).

3. The method of claim 1 , wherein the substrate is flexible.

4. The method of claim 1 , wherein the substrate is optically transparent.

5. The method of claim 1 , wherein a thickness of the first metallic layer and a thickness of the second metallic layer are from about 0.5 nm to about 3.0 nm.

6. The method of claim 1 , wherein at least one of a thickness of the first metallic layer and a composition of the first metallic layer is different than a thickness of the second metallic layer and a composition of the second metallic layer, respectively.

7. The method of claim 1 , wherein passivating the first film, passivating the second film, or both comprise exposing the first metallic layer, the second metallic layer, or both to air or oxygen gas from about 1 second to about 60 seconds.

8. The method of claim 1 , wherein depositing the first metallic layer and depositing the second metallic layer comprises using a vacuum deposition method of magnetron sputtering, electron beam evaporation, thermal evaporation, or ion sputtering.

9. The method of claim 1 , further comprising, straining the substrate up to about 30% prior to depositing the first metallic layer in contact with the substrate.

10. The method of claim 1 further comprising depositing one or more additional metallic layers on the passivated second layer to form an additional deposited metallic layer, and passivating the one or more additional deposited metallic layers prior to depositing a subsequent of the one or more additional metallic layers thereon and in contact therewith.

11. The method of claim 10 , wherein each of the one or more additional metallic layers comprises silver (Ag), copper (Cu), aluminum (Al), or a combination thereof.

12. An electrode comprising: a plurality of metallic layers deposited on a substrate, including a first metallic layer in contact with the substrate, wherein the substrate comprises glass, silicon, or a polymer; and an oxide layer between each adjacent pair of metallic layers, wherein each of the plurality of metallic layers comprises silver (Ag), copper (Cu), aluminum (Al), or a combination thereof, is continuous, and comprises a plurality of grains, wherein an average grain size in each metallic layer of the plurality of metallic layers is less than 50 nm as a result of passivation of each of the metallic layers prior to deposition of a subsequent of the plurality of metallic layers in contact therewith, and wherein the electrode comprises an optical transmittance between 40% to about 89%.

13. The electrode of claim 12 , further comprising an anti-reflective layer comprising a conducting transparent polymer.

14. The electrode of claim 12 , wherein the electrode comprises a thickness of less than about 15 nm.

15. The electrode of claim 14 , wherein an average diameter of the plurality of grains is less than about 20 nm.

16. The electrode of claim 12 , further comprising at least three metallic layers.

17. The electrode of claim 12 , wherein the plurality of metallic layers is flexible.

18. The electrode of claim 12 , wherein a thickness of each of the plurality of metallic layers is uniform, having a difference between a maximum and a minimum thickness of the layer that is within 20% of an average thickness of the layer.

Assignees

• Univ Houston System

Inventors

• Ren Zhifeng
• Guo Chuanfei
• Liu Yuan

Classifications

• H01B1/023

  Alloys based on aluminium · CPC title

• H01B1/22

  the conductive material comprising metals or alloys · CPC title

• H01B1/16 Primary

  the conductive material comprising metals or alloys · CPC title

• H01B13/0036

  Details · CPC title

• H01B1/026

  Alloys based on copper · CPC title