Electrochemical deposition method utilizing microdroplets of solution
A method of electrochemical deposition uses microdroplets of electrolytic solution over a targeted small circuit element. Only the targeted circuit element is electrically biased so that deposition occurs on the surface of that element, underneath the microdroplet, and nowhere else unless it is under other microdroplet(s). The invented method achieves extremely accurate and selective electrochemical deposition with a tiny amount of electrolytic solution, compared to conventional submersive and/or immersive methods, and eliminates the need for masking or etching, reducing the costs of manufacture and amount of waste electrolytic solution produced.
1. A method of selective electrochemical deposition, comprising:
placement of a droplet of electrolytic solution on a substrate;
providing of a first probe in contact with said droplet, but not said substrate;
providing a second probe in said droplet and in contact with a circuit element on said substrate where in a part of said circuit element is in contact with said droplet; and
establishing of an electrical current between said first probe and said second probe to induce electrochemical deposition upon said contacted circuit element.
2. The method of claim 1 , wherein said droplet is a microdroplet.
3. The method of claim 2 , wherein said microdroplet has a volume in the range of less than about 1000 nanoliters.
4. The method of claim 2 , wherein said microdroplet has a volume in the range of about 400 to 700 nanoliters.
5. The method of claim 1 , wherein the area on the substrate receiving deposited material is about 6.25×10 4 micrometers 2 or less.
6. The method of claim 1 , wherein said electrical current is a DC current.
7. The method of claim 1 , wherein said electrical current is an AC current.
8. The method of claim 1 , wherein said electrical current is a constant current.
9. The method of claim 1 , wherein said electrical current is a varying current.
10. The method of claim 1 , wherein said electrical current is created with a constant voltage circuit.
11. The method of claim 1 , wherein said electrical current is created with a varying voltage circuit.
12. The method of claim 1 , wherein the electroactive material in said electrolytic solution deposits as a conductor.
13. The method of claim 1 , wherein the electroactive material in said electrolytic solution is deposited to form a conductor.
14. The method of claim 1 , wherein the electroactive material in said electrolytic solution deposits as a semi-conductor.
15. The method of claim 1 , wherein the electroactive material in said electrolytic solution is deposited to form a semi-conductor.
16. The method of claim 1 , wherein the electroactive material in said electrolytic solution deposits as a nonconductor.
17. The method of claim 1 , wherein the electroactive material in said electrolytic solution is deposited to form a nonconductor.
18. The method of claim 1 , wherein said first probe is a microprobe.
19. The method of claim 1 , wherein said second probe is a microprobe.
20. The method of claim 1 , wherein said first probe comprises a nanowire.
21. The method of claim 1 , wherein said second probe comprises a nanowire.