Transparent conductive circuit
A transparent conductive film (TCF) and methods for creating the TCF. The TCF includes a substrate having a surface, a metal mesh layer over at least a portion of the surface of the substrate, and a conductive layer over the metal mesh layer. The conductive layer includes carbon nanotubes and a binder.
1. A transparent conductive film (TCF), comprising:
a substrate having a surface;
a metal mesh layer over at least a portion of the surface of the substrate;
a conductive layer over the metal mesh layer, the conductive layer comprising carbon nanotubes (CNT) and a binder; and
a second metal layer between the metal mesh layer and the conductive layer.
2. The TCF of claim 1 , wherein the second metal layer comprises a copper layer.
3. The TCF of claim 2 , wherein the copper layer is electroplated on the metal mesh layer.
4. The TCF of claim 1 , wherein the TCF has a sheet resistance of no more than 1 Ohm per square (OPS).
5. The TCF of claim 1 , wherein the metal mesh layer and the conductive layer in combination have a visible light transmittance (VLT) of at least 85%.
6. The TCF of claim 5 , wherein the metal mesh layer and the conductive layer in combination have a VLT of at least 90%.
7. The TCF of claim 1 , wherein the metal mesh layer comprises a network of interconnected metal traces with open spaces between the traces.
8. The TCF of claim 7 , wherein the network is in a hexagonal, rectangular or random pattern.
9. The TCF of claim 7 , wherein the metal mesh layer comprises at least 90% open spaces.
10. The TCF of claim 7 , wherein the metal traces have a line width of no more than 30 microns.
11. The TCF of claim 7 , wherein the open spaces of the metal mesh layer have a width that is at least fifteen times the width of the metal traces.
12. The TCF of claim 7 , defining a circuit with conductive lines having a width, wherein the conductive line width is at least ten times the width of the metal mesh open spaces.
13. The TCF of claim 1 , wherein the metal mesh comprises two different metals, a second metal on top of a first metal.
14. The TCF of claim 13 , wherein the first metal comprises silver and the second metal comprises copper.
15. The TCF of claim 1 , wherein the CNT in the conductive layer comprises a network with an areal density of about 1-10 mg/m2.
16. The TCF of claim 1 , wherein a ratio of binder:CNT in the conductive layer is greater than 120:1.
17. A method of producing a transparent conductive film (TCF), comprising:
providing a substrate having a surface;
depositing a metal mesh layer or a nanowire layer over at least a portion of the surface of the substrate;
depositing a second metal layer on at least some of the metal mesh layer or the nanowire layer; and
patterning a conductive layer over at least some of the second metal layer, the conductive layer comprising carbon nanotubes (CNT) and a binder.
18. The method of claim 17 , wherein the nanowire layer comprises silver nanowires.
19. The method of claim 17 , further comprising etching exposed metal mesh layer or nanowire layer that is not covered by the conductive layer.
20. The method of claim 19 , wherein etching is accomplished by spraying an etchant onto the TCF.
21. The method of claim 20 , wherein the etchant comprises ferric nitrate.
22. A transparent conductive film (TCF), comprising:
a substrate having a surface;
a metal mesh layer over at least a portion of the surface of the substrate, wherein the metal mesh comprises two different metals, a second metal on top of a first metal; and
a conductive layer over the metal mesh layer, the conductive layer comprising carbon nanotubes (CNT) and a binder.
23. A transparent conductive film (TCF), comprising:
a substrate having a surface;
a metal mesh layer over at least a portion of the surface of the substrate; and
a conductive layer over the metal mesh layer, the conductive layer comprising carbon nanotubes (CNT) and a binder, wherein a ratio of binder:CNT in the conductive layer is greater than 120:1.