Magnetic core for use in an integrated circuit, an integrated circuit including such a magnetic core, a transformer and an inductor fabricated as part of an integrated circuit

Patent metadata

Field	Value
Publication number	US-9484136-B2
Application number	US-201313927459-A
Country	US
Kind code	B2
Filing date	Jun 26, 2013
Priority date	Sep 4, 2012
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

A magnetic core is provided for an integrated circuit, the magnetic core comprising: a plurality of layers of magnetically functional material; a plurality of layers of a first insulating material; and at least one layer of an secondary insulating material; wherein layers of the first insulating material are interposed between layers of the magnetically functional material to form subsections of the magnetic core, and the at least one layer of second insulating material is interposed between adjacent subsections.

First claim

What is claimed is:

1. A magnetic core for use in an integrated circuit, the magnetic core comprising:
a plurality of subsections, wherein each subsection of the plurality of subsections comprises a plurality of layers of magnetically functional material, and first insulating layers, wherein each of the first insulating layers is formed of a first insulating material, and wherein adjacent layers of the first insulating layers are interposed between adjacent layers of the layers of the magnetically functional material in each subsection of the plurality of subsections; and
at least one second insulating layer formed of a second insulating material and interposed between adjacent subsections of the plurality of subsections, wherein the second insulating material is different from the first insulating material, and wherein the magnetic core is a single magnetic core that includes the plurality of subsections and the at least one second insulating layer.

2. A magnetic core as claimed in claim 1 , in which a thickness of the at least one second insulating layer is greater than a thickness of a first insulating layer.

3. A magnetic core as claimed in claim 1 , in which the first insulating material acts as a growth substrate for the formation of the magnetically functional material.

4. A magnetic core as claimed in claim 3 , in which the first insulating material is an insulating nitride.

5. A magnetic core as claimed in claim 1 , in which the first insulating material is aluminum nitride or aluminum oxide.

6. A magnetic core as claimed in claim 1 , in which a plurality of layers of magnetically functional material are arranged in an alternating sequence with the first insulating layers to form a subsection of the plurality of subsections.

7. A magnetic core as claimed in claim 1 , in which at least one second insulating layer is bounded on a first side by one of the first insulating layers.

8. A magnetic core as claimed in claim 7 , in which the at least one second insulating is bounded on a second side by a layer of the first insulating layers.

9. A magnetic core as claimed in claim 1 , in which the at least one second insulating layer comprises N- 1 second insulating layers, the plurality of subsections comprises N subsections, and the N- 1 second insulating layers are disposed in the magnetic core so as to divide the magnetic core into N subsections.

10. A magnetic core as claimed in claim 9 , in which the plurality of subsections each comprise substantially equal numbers of layers of magnetically active material.

11. A magnetic core as claimed in claim 1 , in which the magnetically functional material is a ferromagnetic material.

12. A magnetic core as claimed in claim 11 , in which the ferromagnetic material is magnetically soft.

13. A magnetic core as claimed in claim 1 , in which the magnetically functional material is a combination of nickel and iron, or iron and cobalt, or nickel and cobalt or cobalt, zirconium and tantalum.

14. A magnetic core as claimed in claim 1 , in which the second insulating material is a silicon compound.

15. A magnetic core as claimed in claim 1 , in which the second insulating material is a semiconductor oxide.

16. A magnetic core as claimed in claim 1 , in which capacitive coupling between the adjacent subsections is reduced compared to capacitive coupling between adjacent layers of the magnetically functional material in a subsection of the adjacent subsections.

17. A semiconductor substrate having a magnetic core as claimed in claim 1 .

18. An integrated circuit including a magnetic core as claimed in claim 1 .

19. A transformer comprising a magnetic core as claimed in claim 1 .

20. An inductor including a magnetic core a magnetic core as claimed in claim 1 .

21. A magnetic core, as claimed in claim 1 , wherein the at least one second insulating layer comprises two second insulating layers, and wherein a subsection of the plurality of subsections is disposed between the two second insulating layers.

22. A magnetic core comprising:
a plurality of subsections, wherein each subsection of the plurality of subsections comprises a plurality of layers of magnetically functional material and first insulating layers, wherein each of the first insulating layers is formed of a first insulating material, and wherein adjacent layers of the first insulating layers are interposed between adjacent layers of the layers of the magnetically functional material in each subsection of the plurality of subsections; and
at least one second insulating layer formed of a second insulating material and interposed between adjacent subsections of the plurality of subsections, wherein the second insulating material is different from the first insulating material and a permittivity of the second insulating material, is less than a permittivity of the first insulating material, and wherein the magnetic core is a single magnetic core that includes the plurality of subsections and the at least one second insulating layer.

23. A magnetic core for use in an integrated circuit, the magnetic core comprising:
layers of magnetically functional material;
first insulating layers formed of a first insulating material; and
two second insulating layers formed of a second insulating material, wherein the second insulating material is different than the first insulating material;
wherein the magnetic core comprises a subsection between the two second insulating layers, wherein the subsection comprises two or more layers of the magnetically functional material that are each interposed between layers of the first insulating layers, and wherein capacitive coupling between the subsection and an adjacent subsection of the magnetic core is reduced compared to capacitive coupling between adjacent layers of the magnetically functional material of the subsection.

24. A magnetic core as claimed in claim 23 , wherein a permittivity of the second insulating material is less than a permittivity of the first insulating material.

25. A magnetic core as claimed in claim 23 , further comprising two additional subsections.

26. A magnetic core as claimed in claim 23 , wherein the two second insulating materials each has a thickness that is greater than a thickness of any of the first insulating layers.

Assignees

• Analog Devices Global

Inventors

• Morrissey Michael Noel
• Kubik Jan
• Geary Shane Patrick
• Mcguinness Patrick Martin
• O'Sullivan Catriona Marie

Classifications

• H01F27/245

  made from sheets, e.g. grain-oriented (H01F27/26 takes precedence) · CPC title

• H01F27/2804

  Printed windings · CPC title

• H01F2027/2809

  on stacked layers · CPC title

• H01F3/00 Primary

  Cores, Yokes, or armatures (magnetic materials H01F1/00; permanent magnets H01F7/02) · CPC title

• H01F27/24 Primary

  Magnetic cores · CPC title