Laminated magnetic core inductor with insulating and interface layers

Patent metadata

Field	Value
Publication number	US-11064610-B2
Application number	US-201816006450-A
Country	US
Kind code	B2
Filing date	Jun 12, 2018
Priority date	Sep 11, 2012
Publication date	Jul 13, 2021
Grant date	Jul 13, 2021

Abstract

An inductor includes a planar laminated magnetic core and a conductive winding. The planar magnetic core includes an alternating sequence of a magnetic layer and a non-magnetic layer. The non-magnetic layer includes an insulating layer that is disposed between first and second interface layers. The conductive winding turns around in a generally spiral manner on the outside of the planar laminated magnetic core. The inductor can be integrated into a multilevel wiring network in a semiconductor integrated circuit to form a microelectronic device, such as a transformer, a power converter, or a microprocessor.

First claim

What is claimed is:

1. An inductor comprising:
a planar laminated magnetic core comprising an alternating sequence of a magnetic layer and a non-magnetic layer, wherein the non-magnetic layer comprises an insulating layer disposed between first and second interface layers; and
a conductive winding that turns around in a generally spiral manner on the outside of said planar laminated magnetic core,
wherein the non-magnetic layer comprises (a) silicon, tantalum, aluminum, chromium, cobalt, or titanium and (b) oxygen, and the first and second interface layers reduce a first root mean squared roughness and a second root mean squared roughness to less than or equal to 20 angstroms, the first root mean squared roughness at an interface between a first magnetic layer and the first interface layer, the second root mean squared roughness at an interface between a second magnetic layer and the second interface layer.

2. The inductor of claim 1 , wherein the first and second interface layers comprise a material and the insulating layer comprises a compound of (a) the material and (b) oxygen, nitrogen, or a combination thereof.

3. The inductor of claim 1 , wherein the first and second interface layers comprise a material that includes silicon, tantalum, aluminum, chromium, cobalt, titanium, or a combination of two or more of the foregoing.

4. The inductor of claim 3 , wherein the insulating layer comprises a compound of the material and oxygen.

5. The inductor of claim 3 , wherein the insulating layer comprises a compound of the material and nitrogen.

6. The inductor of claim 3 , wherein the insulating layer comprises a compound of the material, oxygen, and nitrogen.

7. The inductor of claim 1 , wherein the non-magnetic layer comprises (a) silicon, tantalum, aluminum, chromium, cobalt, or titanium and (b) oxygen and nitrogen.

8. The inductor of claim 1 , wherein the first and second interface layers inhibit a diffusion of oxygen, nitrogen, or a combination thereof from the insulating layer into a neighboring magnetic layer.

9. The inductor of claim 1 , wherein the magnetic layer comprises an anisotropic magnetic material having a hard axis of magnetization that is at least partially aligned with an axis of the conductive winding, the conductive winding extending along the axis of the conductive winding.

10. The inductor of claim 1 , further comprising:
a final magnetic layer disposed on a last non-magnetic layer, the last non-magnetic layer in the alternating sequence; and
a capping layer disposed on the final magnetic layer on a first side of the planar laminated magnetic core, wherein the capping layer and the first and second interface layers comprise the same material.

11. The inductor of claim 10 , further comprising an adhesion layer disposed below a final magnetic layer on a second side of the planar laminated magnetic core, wherein the adhesion layer and the first and second interface layers comprise the same material, and the first and second sides are on opposite sides of the planar laminated magnetic core.

12. A microelectronic device comprising:
a semiconductor integrated circuit comprising a multilevel wiring network; and
an inductor integrated into said multilevel wiring network, said inductor comprising a planar laminated magnetic core and a conductive winding that turns around in a generally spiral manner on the outside of said planar laminated magnetic core, said planar laminated magnetic core comprising an alternating sequence of a magnetic layer and a non-magnetic layer, wherein the non-magnetic layer comprises an insulating layer disposed between first and second interface layers,
wherein the non-magnetic layer comprises (a) silicon, tantalum, aluminum, chromium, cobalt, or titanium and (b) oxygen, and the first and second interface layers reduce a first root mean squared roughness and a second root mean squared roughness to less than or equal to 20 angstroms, the first root mean squared roughness at an interface between a first magnetic layer and the first interface layer, the second root mean squared roughness at an interface between a second magnetic layer and the second interface layer.

13. The microelectronic device of claim 12 , wherein the inductor and at least a portion of the semiconductor integrated circuit form a transformer.

14. The microelectronic device of claim 12 , wherein the inductor and at least a portion of the semiconductor integrated circuit form a power converter.

15. The microelectronic device of claim 12 , wherein the inductor and at least a portion of the semiconductor integrated circuit form a microprocessor.

16. The microelectronic device of claim 12 , wherein the magnetic layer comprises an anisotropic magnetic material having a hard axis of magnetization that is at least partially aligned with an axis of the conductive winding, the conductive winding extending along the axis.

17. The microelectronic device of claim 12 , wherein the first and second interface layers comprise a material and the insulating layer comprises a compound of (a) the material and (b) oxygen, nitrogen, or a combination thereof.

18. The microelectronic device of claim 12 , wherein the first and second interface layers comprise a material that includes silicon, tantalum, aluminum, chromium, cobalt, titanium, or a combination of two or more of the foregoing.

19. The microelectronic device of claim 18 , wherein the insulating layer comprises a compound of the material and oxygen.

20. The microelectronic device of claim 18 , wherein the insulating layer comprises a compound of the material and nitrogen.

21. The microelectronic device of claim 18 , wherein the insulating layer comprises a compound of the material, oxygen, and nitrogen.

22. The microelectronic device of claim 12 , wherein the non-magnetic layer comprises (a) silicon, tantalum, aluminum, chromium, cobalt, or titanium and (b) oxygen and nitrogen.

23. The microelectronic device of claim 12 , wherein the first and second interface layers inhibit a diffusion of oxygen, nitrogen, or a combination thereof from the insulating layer into a neighboring magnetic layer.

24. The microelectronic device of claim 12 , further comprising:
a final magnetic layer disposed on a last non-magnetic layer, the last non-magnetic layer in the alternating sequence; and
a capping layer disposed on the final magnetic layer on a first side of the planar laminated magnetic core, wherein the capping layer and the first and second interface layers comprise the same material.

25. The microelectronic device of claim 24 , further comprising an adhesion layer disposed on a first magnetic layer on a second side of the planar laminated magnetic core, the second side of the planar magnetic core disposed closer to a semiconductor substrate in the semiconductor integrated circuit than the first side of the planar magnetic core, the adhesion layer and the first and second interface layers comprising the same material.

26. A microelectronic device comprising:
a semiconductor integrated circuit comprising a multilevel wiring network; and
an inductor integrated into said multilevel wiring network, said inductor comprising a planar laminated magnetic core and a conductive winding that turns around in a generally spiral manner on the outside of said planar laminated magnetic core, said planar laminated magnetic core comprising an alternating sequence of a magnetic layer an

Assignees

• Ferric Inc

Inventors

• Sturcken Noah
• Davies Ryan
• Lekas Michael

Classifications

• H10D1/20 Primary

  Inductors · CPC title

• H05K1/0306

  Inorganic insulating substrates, e.g. ceramic, glass · CPC title

• Y10T29/4913

  Assembling to base an electrical component, e.g., capacitor, etc. · CPC title

• H01F41/02

  for manufacturing cores, coils, or magnets (H01F41/14 takes precedence; for dynamo-electric machines H02K15/00) · CPC title

• H05K1/0298

  Multilayer circuits · CPC title