Micro-channel connection method
View Patent ↗A method of making a connection-pad structure includes providing a substrate and coating a curable layer over the substrate. A group of intersecting micro-channels is embossed in the curable layer. Each micro-channel extends from a surface of the curable layer into the curable layer toward the substrate. The curable layer is cured to form a cured layer having embossed intersecting micro-channels in the cured layer; the group of intersecting micro-channels forms a connection pad. A curable electrical conductor is located in the intersecting micro-channels. The curable electrical conductor is cured to form an electrically continuous cured electrical conductor formed in the group of intersecting micro-channels and an electrical connector is electrically connected to the cured electrical conductor.
1. A method of making a connection-pad structure, comprising:
providing a substrate;
coating a curable layer directly on the substrate;
embossing the curable layer with an embossing stamp to form a group of intersecting micro-channels in the curable layer, each micro-channel extending from a surface of the curable layer into the curable layer toward the substrate;
curing the curable layer to form a cured layer having embossed intersecting micro-channels in the cured layer, wherein the group of intersecting micro-channels forms a connection pad;
placing a curable electrical conductor in the intersecting micro-channels;
curing the curable electrical conductor to form an electrically continuous cured electrical conductor formed in the group of intersecting micro-channels; and
electrically connecting an electrical connector to the cured electrical conductor; and
wherein the micro-channels have a width less than 20 microns and greater than or equal to 0.5 microns and a depth less than 20 microns and greater than or equal to 0.5 microns.
2. The method of claim 1 , wherein the step of electrically connecting an electrical connector to the cured electrical conductor further includes:
locating a conductive particle in electrical contact with the electrical connector and the electrical conductor.
3. The method of claim 2 , further including heating the conductive particle, the electrical connector, and the electrical conductor to solder, sinter, or weld them together.
4. The method of claim 1 , wherein the step of electrically connecting an electrical connector to the cured electrical conductor further includes:
locating a conductive paste in electrical contact with the connection pad; and
locating the electrical connector in electrical contact with the conductive paste.
5. The method of claim 4 , further including heating the conductive paste, the electrical connector, and the electrical conductor to solder or sinter them together.
6. The method of claim 5 , wherein the step of heating the conductive paste causes the solder to flow into the intersecting micro-channels.
7. The method of claim 1 , further including coating a slurry or powder containing conductive particles over a surface of the cured layer so that one or more conductive particles is located in one or more of the intersecting micro-channels.
8. The method of claim 1 , wherein the step of locating a curable electrical conductor in one or more of the intersecting micro-channels includes coating a conductive ink over a surface of the curable layer.
9. The method of claim 5 , wherein the conductive ink includes conductive particles.
10. The method of claim 1 , further including spraying, dropping, or locating conductive particles over a surface of the curable layer so that one or more conductive particles is located in one or more of the intersecting micro-channels.
11. The method of claim 10 , further including agitating the conductive particles relative to the substrate.
12. The method of claim 10 , further including masking a surface of the cured layer to expose the connection pad.
13. The method of claim 10 , further including screen printing the conductive particles onto the connection pad.