Nanowires plated on nanoparticles

Patent metadata

Field	Value
Publication number	US-11282807-B2
Application number	US-202016843559-A
Country	US
Kind code	B2
Filing date	Apr 8, 2020
Priority date	Apr 8, 2019
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

In some examples, a system comprises a set of nanoparticles and a set of nanowires extending from the set of nanoparticles.

First claim

What is claimed is:

1. A system, comprising:
a set of nanoparticles; and
a set of nanowires extending from the set of nanoparticles.

2. The system of claim 1 , wherein at least one nanowire of the set of nanowires has a length that is at least twice its diameter.

3. The system of claim 1 , wherein at least one nanowire of the set of nanowires has a diameter of no more than 1 micron.

4. The system of claim 1 , wherein at least one nanowire of the set of nanowires has a length of at least 2 microns.

5. The system of claim 1 , wherein the system comprises a metal layer on which the set of nanoparticles is positioned.

6. The system of claim 1 , wherein the set of nanoparticles comprises titanium and wherein the set of nanowires comprises gold.

7. The system of claim 1 , further comprising:
a first surface on which the set of nanoparticles is positioned;
a second surface on which a second set of nanoparticles is positioned; and
a second set of nanowires extending from the second set of nanoparticles,
wherein the set of nanowires and the second set of nanowires couple to each other.

8. The system of claim 1 , further comprising a first surface on which the set of nanoparticles is disposed, wherein the set of nanowires couples to a second surface, and wherein the first and second surfaces are positioned within a package.

9. The system of claim 1 , wherein the set of nanowires forms a heat sink coupled to a semiconductor die.

10. The system of claim 1 , further comprising:
a die, the set of nanoparticles positioned on a first surface of the die;
a busbar having a second set of nanoparticles positioned thereupon, a second set of nanowires extending from the second set of nanoparticles, the second set of nanowires fused to the set of nanowires;
a substrate coupled to a first metal layer, the first metal layer coupled to the die by way of a third set of nanowires; and
a second metal layer coupled to the substrate, the second metal layer coupled to a third metal layer by way of a fourth set of nanowires,
wherein the third metal layer comprises a fifth set of nanowires positioned external to a package housing the die, the first metal layer, and the second metal layer.

11. The system of claim 10 , further comprising a third set of nanoparticles positioned on the die and a fourth set of nanoparticles positioned on the first metal layer, the third set of nanowires extending from the third set of nanoparticles and a sixth set of nanowires extending from the fourth set of nanoparticles, the third and sixth sets of nanowires fused to each other.

12. The system of claim 10 , wherein the fifth set of nanowires and the fourth set of nanowires are positioned on opposing surfaces of the second metal layer.

13. The system of claim 10 , wherein the substrate comprises a ceramic substrate.

14. A system, comprising:
a first surface;
a first set of nanoparticles coupled to the first surface;
a first set of nanowires extending from the first set of nanoparticles;
a second surface;
a second set of nanoparticles coupled to the second surface; and
a second set of nanowires extending from the second set of nanoparticles, the first and second sets of nanowires fused to each other.

15. The system of claim 14 , wherein at least one of the first set of nanowires has length and diameter dimensions such that the at least one of the first set of nanowires has a melting point between 65 and 175 degrees Fahrenheit.

16. The system of claim 14 , wherein the first surface comprises a metal layer.

17. The system of claim 14 , wherein the first surface comprises a semiconductor.

18. The system of claim 14 , wherein at least one nanowire of the first set of nanowires has a length that is at least twice its diameter.

19. The system of claim 14 , wherein the first surface, the first set of nanoparticles, and the first set of nanowires are part of a semiconductor package, and wherein the second surface, the second set of nanoparticles, and the second set of nanowires are part of a printed circuit board (PCB).

20. The system of claim 14 , wherein the first surface is that of a semiconductor die and the second surface is that of a portion of a lead frame, and wherein the first and second surfaces are positioned within a semiconductor package.

21. The system of claim 20 , wherein the semiconductor die has a third surface opposite the first surface, a third set of nanoparticles positioned on the third surface, a third set of nanowires extending from the third set of nanoparticles, the third set of nanowires forming a heat sink exposed to an exterior of the semiconductor package.

22. The system of claim 14 , wherein the first surface is that of a die, and the second surface is that of a busbar, the system further comprising:
a metal layer coupled to the die by way of a third set of nanowires, the metal layer having a fourth set of nanowires positioned external to a semiconductor package housing the die.

23. The system of claim 22 , further comprising a third set of nanoparticles coupled to the die and a fourth set of nanoparticles coupled to the metal layer, the third set of nanowires coupled to the third and fourth sets of nanoparticles.

24. The system of claim 23 , further comprising a fifth set of nanowires coupled to the die, wherein the third set of nanowires couples to the metal layer, the third and fifth sets of nanowires fused to each other.

25. A method, comprising:
depositing a set of nanoparticles on a surface;
positioning a template over the set of nanoparticles, the template having a plurality of orifices extending perpendicular to the surface;
electroplating the set of nanoparticles to cause a set of nanowires to extend from the set of nanoparticles and through the plurality of orifices; and
removing the template from the surface.

26. The method of claim 25 , further comprising patterning a photoresist on the surface, the photoresist abutting at least one nanoparticle of the set of nanoparticles.

27. The method of claim 26 , further comprising abutting the template to the photoresist.

28. The method of claim 25 , wherein the surface comprises a metal layer.

29. The method of claim 28 , wherein the metal layer and the set of nanoparticles are composed of a same metal.

30. The method of claim 28 , wherein the metal layer and the set of nanoparticles are composed of different metals.

Assignees

• Texas Instruments Inc

Inventors

• Cook Benjamin Stassen
• Muenster Ralf Jakobskrueger
• Koduri Sreenivasan Kalyani

Classifications

• H10W72/551

  Materials of bond wires · CPC title

• H10W72/0198

  batch processes · CPC title

• H10W72/884

  Die-attach connectors and bond wires · CPC title

• H10W72/886

  Die-attach connectors and strap connectors · CPC title

• H10W72/952

  comprising metals or metalloids, e.g. PbSn, Ag or Cu · CPC title