Via for magnetic core of inductive component

Patent metadata

Field	Value
Publication number	US-2018358166-A1
Application number	US-201816003621-A
Country	US
Kind code	A1
Filing date	Jun 8, 2018
Priority date	Jun 9, 2017
Publication date	Dec 13, 2018
Grant date	—

Abstract

Techniques for fabricating low-loss magnetic vias within a magnetic core are provided. According to some embodiments, vias with small, well-defined sizes may be fabricated without reliance on precise alignment of layers. According to some embodiments, a magnetic core including a low-loss magnetic via can be wrapped around conductive coils of an inductor. The low-loss magnetic vias can improve performance of an inductive component by improving the quality factor relative to higher loss magnetic vias.

First claim

What is claimed is:

1 . A magnetic core of an integrated circuit, the magnetic core comprising:
a first layer of the magnetic core; a second layer of the magnetic core, wherein the first layer and the second layer of the magnetic core each comprise layers of magnetic material and at least one lamination layer; and a via magnetically coupling the first layer to the second layer, wherein the via extends through an insulating layer.

2 . The magnetic core of claim 1 , wherein the insulating layer has a width that is less than 5 times a thickness of the first layer.

3 . The magnetic core of claim 1 , wherein the via has a width that is narrower than other portions of magnetic material coupling the first layer to the second layer.

4 . The magnetic core of claim 1 , further comprising a lamination layer at an interface between the first layer of the magnetic core and the via.

5 . The magnetic core of claim 1 , further comprising a plurality of additional vias magnetically coupling the first layer and the second layer.

6 . The magnetic core of claim 1 , wherein the via has a width that is smaller than twice a thickness of the first layer.

7 . An inductor comprising the magnetic core of claim 1 and a coil extending through the magnetic core.

8 . A transformer for transferring power and providing galvanic isolation, the transformer comprising:
a primary coil and a secondary coil; and a magnetic core comprising a first layer of the magnetic core, a second layer of the magnetic core, and a via coupling the first layer of the magnetic core to the second layer of the magnetic core; wherein at least a portion of the primary coil, at least a portion of the secondary coil, and insulation layers are disposed between the first layer and the second layer; and wherein the via passes through a separation layer to provide a pathway for magnetic flux between the first layer and the second layer; wherein the separation layer is between the first layer and the second layer on opposing sides of the via; and wherein the separation layer is thinner than a combination of thicknesses of the portion of the primary coil, the portion of the secondary coil, and the insulating layers.

9 . The transformer of claim 8 , wherein the via has width that is narrower than a width the first layer of the magnetic core that extends substantially parallel to the second layer of the magnetic core.

10 . The transformer of claim 8 , wherein the first layer is coupled to a semiconductor substrate, and wherein a distance from separation layer to the semiconductor substrate is smaller than a distance from either the primary or secondary coil to the semiconductor substrate.

11 . The transformer of claim 8 , further comprising a lamination layer at an interface coupling the first layer to the via.

12 . The transformer of claim 11 , wherein a thickness of the lamination layer is 10 nm or smaller.

13 . The transformer of claim 8 , wherein the via passes through the separation layer at a sloped angle.

14 . The transformer of claim 8 , further comprising a plurality of vias arranged in at least two rows.

15 . The transformer of claim 8 , further comprising additional vias arranged in a row with the via.

16 . The transformer of claim 8 , wherein at least one of the primary coil or the secondary coil has a non-uniform turns density configured to compensate for magnetic core saturation non-uniformity of the magnetic core.

17 . A transformer for transferring power and providing galvanic isolation, the transformer comprising:
an upper layer of a magnetic core; a lower layer of the magnetic core; a first conductor coil at least part of which is arranged between the upper layer and the lower layer; a second conductor coil at least part of which is arranged between the upper layer and the lower layer; and a via comprising magnetic material, the via providing a pathway for magnetic flux between the upper layer and the lower layer.

18 . The transformer of claim 17 , wherein the via has substantially the same width along the entirety of the via.

19 . The transformer of claim 17 , wherein the lower layer of the magnetic core is disposed on a substrate, and wherein at least some of the first or second conductor coils are located in a trench between a first and a second raised substrate step.

20 . The transformer of claim 17 , wherein at least one of the first conductor coil or the second conductor coil has a non-uniform turns density configured to compensate for magnetic core saturation non-uniformity of the magnetic core.

Assignees

• Analog Devices Global Unlimited Co

Inventors

• Kubik Jan
• Stenson Bernard Patrick
• Morrissey Michael

Classifications

• H01F27/263 Primary

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• H01F2027/2809

  on stacked layers · CPC title

• H01F2027/348

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