Plating of multi-layer structures
View Patent ↗An insulating layer ( 5 ) and a conductive seed layer ( 6 ) are applied to a substrate ( 1 ) in a simple process. A photo resist with palladium chloride are provided in a bath for electrophoretic deposition onto the substrate. The photo resist is an insulator and the palladium chloride is a catalyst. The layer is heated with UV to cure it. The layer is plasma etched to expose more of the palladium chloride, which acts as a catalyst for electrodes plating of the conductive seed layer. A thicker conductive layer ( 7 ) is then electroplated onto the seed layer. These steps may be repeated for successive insulating and/or conductive layers.
1. A method of applying layers to conductive areas of a substrate comprising the steps of:
(a) electrophoretically depositing an insulator onto said conductive areas of the substrate to provide an insulating layer, wherein a catalyst is co-deposited with the insulating layer, and wherein the insulating layer is electrophoretically deposited from an emulsion of insulator particles, and the catalyst is dissolved in solution in the emulsion; and
(b) electroless plating a conductive layer onto the insulating layer, in which the catalyst activates the electroless plating;
wherein the insulating layer is activated before electroless plating of the conductive layer; and wherein the insulating layer is activated by plasma etching to remove a surface portion of the insulating layer to expose the catalyst.
2. The method as claimed in claim 1 , wherein the electrophoretically deposited insulator is a polymer.
3. The method as claimed in claim 1 , wherein the electrophoretically deposited insulator is a photoresist.
4. The method as claimed in claim 1 , wherein the electroless plated conductive layer is as a seed layer for further plating.
5. The method as claimed in claim 4 , comprising the further steps of electrodepositing conductor material on the seed layer, and subsequently repeating steps (a) and (b) for multiple insulator/conductor layers.
6. The method as claimed in claim 1 , wherein the catalyst is selected from Group 8B of the Periodic Table consisting of iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum.
7. The method as claimed in claim 1 , wherein the catalyst comprises Palladium.
8. The method as claimed in claim 1 , wherein the catalyst comprises Palladium; and wherein the catalyst is palladium chloride, at a concentration to provide ions trapped within the insulator.
9. The method as claimed in claim 1 , wherein the catalyst is diluted in a solution for pH adjustment for pH compatibility with the insulator.
10. The method as claimed in claim 1 , wherein the catalyst comprises Palladium; and wherein the insulator and the catalyst are electrophoretically deposited from a bath containing photo resist, palladium chloride, water, hydrochloride acid, and ammonia.
11. The method as claimed in claim 1 , comprising the further steps of heating the insulating layer before step (b).
12. The method as claimed in claim 1 , wherein the insulating layer is exposed to a UV source.
13. The method as claimed in claim 1 , comprising the further steps of heating the insulating layer before step (b); and wherein the heating is performed in successive steps separated by intervals.
14. The method as claimed in claim 1 , wherein the conductive areas of the substrate are a metal pattern.
15. The method as claimed in claim 1 , wherein multiple conductor and insulator layers are applied.
16. The method as claimed in claim 1 , wherein the conductor layer is magnetic and forms a laminated core of a magnetic component.
17. The method as claimed in claim 1 , wherein the insulating layer is applied on vertical and horizontal surfaces.
18. The method as claimed in claim 1 , wherein there are a plurality of conductive layers deposited as windings of a magnetic component.
19. A method of applying layers to conductive areas of a substrate, the method comprising the steps of:
(a) electrophoretically depositing an insulator onto said conductive areas of the substrate to provide an insulating layer, wherein a catalyst is co-deposited with the insulating layer; and
(b) electroless plating a conductive layer onto the insulating layer, in which the catalyst activates the electroless plating,
wherein the insulating layer is activated by plasma etching to remove a surface portion of the insulating layer to expose the catalyst before electroless plating of the conductive layer.