Laser patterning of multi-layer structures
A method of non-ablatively laser patterning a multi-layer structure, the multi-layer structure including a substrate, a first layer disposed on the substrate, a second layer disposed on the first layer, and a third layer disposed on the second layer, the method including generating at least one laser pulse having laser parameters selected for non-ablatively changing the conductivity a selected portion of the third layer such that the selected portion becomes non-conductive, and directing the pulse to the multi-layer structure, wherein the conductivity of the first layer is not substantially changed by the pulse.
1. A multi-layer structure, comprising:
a substrate;
a first layer situated on the substrate and having a conductive first portion and a non-conductive second portion adjacent the conductive first portion;
an insulating second layer situated on the first layer; and
a silver nano-wire third layer situated on the insulating second layer and having a conductive first portion and a non-ablatively laser formed non-conductive second portion adjacent to the conductive first portion.
2. The multi-layer structure of claim 1 , wherein the conductive first portion of the first layer has a higher laser pulse conductivity alteration threshold than the conductive first portion of the silver nano-wire third layer.
3. The multi-layer structure of claim 1 , wherein the conductive first portion of the first layer is indium tin oxide (ITO) and the non-conductive second portion of the first layer is ablated ITO.
4. The multi-layer structure of claim 1 , wherein the non-conductive second portion of the silver nano-wire third layer overlies the non-conductive second portion of the first layer.
5. The multi-layer structure of claim 1 , wherein the first layer includes silver nanowires.
6. The multi-layer structure of claim 1 , wherein the insulating second layer comprises photoresist.
7. The multi-layer structure of claim 1 , wherein the insulating second layer is situated to protect the first layer from a change in conductivity during non-ablative laser processing of the third layer.
8. The multi-layer structure of claim 7 , wherein the second layer is situated to scatter or absorb energy during the non-ablative laser processing of the third layer.
9. The multi-layer structure of claim 1 , wherein the first layer comprises a heat-treated layer.
10. The multi-layer structure of claim 9 , wherein the heat-treated layer has a higher laser pulse conductivity altering threshold, relative to a laser pulse conductivity altering threshold of the conductive first portion of the silver nano-wire third layer, based on the heat treatment.
11. The multi-layer structure of claim 1 , wherein the substrate comprises a substrate layer of polyethylene terephthalate (PET).
12. A touch-sensitive screen, comprising the multi-layer structure of claim 1 .
13. A touch-sensitive sensor, comprising the multi-layer structure of claim 1 .
14. The multi-layer structure of claim 1 , wherein conductive first portion of the silver nano-wire third layer has a sheet resistance from 30-250 Ω/sq.
15. The multi-layer structure of claim 1 , wherein non-conductive second portion of the silver nano-wire third layer has a sheet resistance greater than or equal to about 20 MΩ/sq.
16. The multi-layer structure of claim 1 , wherein the conductive first portion and non-conductive second portion of the silver nano-wire third layer have a same surface roughness.
17. The multi-layer structure of claim 1 , wherein to an unaided eye of an observer the conductive first portion and non-conductive second portion of the silver nano-wire third layer are visibly indistinguishable from each other.
18. The multi-layer structure of claim 1 , wherein the conductive matrix of silver nanowires includes an organic overcoat.