Methods of forming conductive elements using organometallic layers and flowable, curable conductive materials

• US 20060115926A1
• Filed: 01/20/2006
• Published: 06/01/2006
• Est. Priority Date: 09/02/2004
• Status: Active Grant

• Current Assignee: Alan G. Wood, Charles M. Watkins, Peter A. Benson, Warren M. Farnworth
• Original Assignee: Alan G. Wood, Charles M. Watkins, Peter A. Benson, Warren M. Farnworth
• Inventors: Watkins, Charles M., Farnworth, Warren M., Wood, Alan G., Benson, Peter A.
• Granted Patent: US 7,442,643 B2
• Time in Patent Office: Days
• US Class Current: 438/106
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: H01L 21/56 Encapsulations, e.g. encapsulation layers, coatings
• CPC Class Codes: H01L 2224/04105 Bonding areas formed on an encapsulation of the semiconductor or solid-state body, e.g. bonding areas on chip-scale packages
• CPC Class Codes: H01L 2224/20 Structure, shape, material or disposition of high density interconnect preforms
• CPC Class Codes: H01L 23/3128 the substrate having spherical bumps for external connection
• CPC Class Codes: H01L 27/14618 Containers
• CPC Class Codes: H01L 27/14627 Microlenses
• CPC Class Codes: H01L 27/14685 Process for coatings or optical elements
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01027 Cobalt [Co]
• CPC Class Codes: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/12041 LED

Abstract

A conductive element is formed on a substrate by forming an organometallic layer on at least a portion of a surface of the substrate, heating a portion of the organometallic layer, and removing an unheated portion of the organometallic layer. In other methods, a flowable, uncured conductive material may be deposited on a surface of the substrate, the flowable, uncured conductive material may be selectively cured over at least a portion of the surface of the substrate, and a portion of the cured conductive material may be removed. A conductive via is formed by forming a hole at least partially through a thickness of a substrate, depositing an organometallic material within at least a portion of the hole, and selectively heating at least a portion of the organometallic material.

Claims

1. A method of forming a conductive element onto a substrate, comprising:

forming an organometallic layer onto at least a portion of a surface of a substrate;

heating, at most, a portion of the organometallic layer; and

removing an unheated portion of the organometallic layer.

2. The method of claim 1, wherein removing the unheated portion of the organometallic layer comprises exposing the organometallic layer to a solvent after heating the portion of the organometallic layer.

3. The method of claim 1, wherein forming the conductive element comprises forming a conductive trace.

4. The method of claim 1, wherein forming the organometallic layer onto at least the portion of the surface of the substrate comprises forming an organometallic layer onto at least a portion of a surface of at least one of a ceramic substrate, an FR4 substrate, or a polyimide substrate.

5. The method of claim 1, wherein heating, at most, the portion of the organometallic layer comprises selectively heating the portion of the organometallic layer with a laser beam.

6. The method of claim 5, wherein removing the unheated portion of the organometallic layer comprises exposing the organometallic layer to a solvent after selectively heating the portion of the organometallic layer with the laser beam.

7. The method of claim 1, further comprising plating a metal onto the heated portion of the organometallic layer.

8. The method of claim 7, wherein plating the metal onto the selectively exposed portion of the organometallic layer comprises at least one of electrolytic plating and electroless plating.

9. A method of forming a conductive via, comprising:

forming a hole at least partially through a thickness of a substrate;

depositing an organometallic material within at least a portion of the hole;

selectively heating at least a portion of the organometallic material.

10. The method of claim 9, further comprising exposing the organometallic material to a solvent after selectively heating the at least a portion of the organometallic material.

11. The method of claim 10, wherein selectively heating the at least a portion of the organometallic material comprises selectively heating the at least a portion of the organometallic material with a laser beam.

12. The method of claim 9, further comprising plating a metal onto the at least a portion of the organometallic material.

13. The method of claim 12, wherein plating the metal onto the at least a portion of the organometallic layer comprises at least one of electrolytic plating and electroless plating.

14. The method of claim 9, wherein depositing the organometallic material within the at least a portion of the hole comprises depositing a plurality of sequential layers of the organometallic material within the at least a portion of the hole.

15. The method of claim 9, wherein forming the hole at least partially through the thickness of the substrate comprises ablating the hole at least partially through the thickness of the substrate with a laser beam.

16. The method of claim 9, wherein selectively heating the at least a portion of the organometallic material comprises heating the at least a portion of the organometallic material with a laser beam.

17. The method of claim 16, further comprising exposing the organometallic material to a solvent after selectively heating the at least a portion of the organometallic material with the laser beam.

18. The method of claim 9, wherein selectively heating the at least a portion of the organometallic material comprises selectively heating a portion of the organometallic material adjacent to a boundary wall of the hole and forming a bore therewith.

19. The method of claim 18, wherein selectively heating the portion of the organometallic material adjacent to the boundary wall of the hole and forming the bore therewith comprises selectively heating a plurality of sequential layers of the organometallic material adjacent to the boundary wall of the hole.

20. A method of forming a conductive element onto a substrate, the method comprising:

depositing a flowable, uncured conductive material onto a surface of a substrate;

selectively curing the flowable, uncured conductive material over at least a portion of the surface thereof;

removing a portion of the cured conductive material.

21. The method of claim 20, wherein depositing the flowable, uncured conductive material onto the surface of the substrate comprises at least one of immersing, dipping, spin-coating, stamping, printing, and spraying.

22. The method of claim 20, wherein depositing the flowable, uncured conductive material onto the surface of the substrate comprises depositing the flowable, uncured conductive material onto the surface of the substrate by way of at least one of maskless mesoscale materials deposition, 3-D printing deposition, and micropen deposition.

23. The method of claim 20, wherein selectively curing the flowable, uncured conductive material over the at least a portion of the surface thereof comprises curing the flowable, uncured conductive material over substantially the entire surface of the substrate.

24. The method of claim 20, wherein removing the portion of the cured conductive material comprises removing the portion by etching.

25. The method of claim 20, wherein depositing the flowable, uncured conductive material onto the surface of the substrate comprises depositing a conductive photopolymer.

26. The method of claim 25, wherein depositing the conductive photopolymer onto the surface of the substrate comprises at least one of immersing, dipping, spin-coating, printing, and spraying.