Micromagnetic device having an anisotropic ferromagnetic core and method of manufacture therefor

• US 6,191,495 B1
• Filed: 04/16/1999
• Issued: 02/20/2001
• Est. Priority Date: 06/10/1997
• Status: Expired due to Term

• Current Assignee: Bell Semiconductor, LLC (Hilco Inc. (d/b/a Hilco Global))
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Lotfi, Ashraf W., Steigerwald, Michael L., Kossives, Dean P., Van Dover, R. Bruce, Schneemeyer, Lynn F.
• Primary Examiner(s): Fahmy, Wael
• Assistant Examiner(s): Berezny, Neal
• Application Number:
  US09/292,860
• Time in Patent Office: 676 Days
• Field of Search: 257/421, 257/798, 438/3, 438/22, 365/131, 365/140, 365/141, 365/145, 365/156, 365/157, 427/548, 360/313, 360/318, 360/328, 360/123, 360/125, 360/126
• US Class Current: 257/798
• CPC Class Codes: H01F 17/0006 Printed inductances printed coils for dynamo-electric machines H02K3/26; printed circuits H05K
• CPC Class Codes: H01F 41/046 structurally combined with ferromagnetic material
• CPC Class Codes: H01L 23/5227 Inductive arrangements or effects of, or between, wiring layers other inductive arrangements H01L23/645
• CPC Class Codes: H01L 23/645 Inductive arrangements H01L23/647, H01L23/66 take precedence
• CPC Class Codes: H01L 27/016 Thin-film circuits
• CPC Class Codes: H01L 27/08 including only semiconductor components of a single kind
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/3011 Impedance

Abstract

For use with an integrated circuit having a substrate and an insulator coupled to the substrate, a micromagnetic device and method of manufacturing therefor. In one embodiment, the micromagnetic device includes an adhesive coupled to the insulator and a ferromagnetic core, coupled to the adhesive that forms a bond between the insulator and the ferromagnetic core, having an anisotropic property.

Claims

1. For use with an integrated circuit having a substrate and an insulator coupled to said substrate, a micromagnetic device, comprising:

an adhesive coupled to said insulator; and

a ferromagnetic core, of said micromagnetic device, coupled to said adhesive that forms a bond between said insulator and said ferromagnetic core, having an anisotropic property.

2. The micromagnetic device as recited in claim 1 wherein said ferromagnetic core comprises an easy axis and a hard axis.

3. The micromagnetic device as recited in claim 1 wherein said ferromagnetic core comprises an easy axis substantially transverse to a hard axis.

4. The micromagnetic device as recited in claim 1 wherein said adhesive is a metallic adhesive.

5. The micromagnetic device as recited in claim 1 wherein said ferromagnetic core contains an alloy material.

6. The micromagnetic device as recited in claim 1 wherein said insulator includes an organic polymer.

7. The micromagnetic device as recited in claim 1 wherein said micromagnetic device further comprises a winding surrounding at least a portion of said ferromagnetic core.

8. A micromagnetic device for use with an integrated circuit having a substrate, comprising:

a first conductive winding layer formed over said substrate;

a first insulative layer formed over said first conductive winding layer;

a metallic adhesive formed over said first insulative layer; and

a ferromagnetic core, of said micromagnetic device, formed over said metallic adhesive and having an anisotropic property, said metallic adhesive forming a bond between said first insulative layer and said ferromagnetic core to secure said ferromagnetic core to said substrate.

9. The micromagnetic device as recited in claim 8 further comprising a passivation layer interposed between said substrate and said first conductive winding layer.

10. The micromagnetic device as recited in claim 8 further comprising a second insulative layer formed over said ferromagnetic core.

11. The micromagnetic device as recited in claim 10 further comprising a second conductive winding layer formed over said second insulative layer.

12. The micromagnetic device as recited in claim 11 further comprising a third insulative layer formed over said second conductive winding layer.

13. The micromagnetic device as recited in claim 12 further comprising at least one terminal formed in said third insulative layer.

14. The micromagnetic device as recited in claim 8 wherein said metallic adhesive comprises a layer that contains a material selected from the group consisting of:

zirconium; and

hafnium.

15. The micromagnetic device as recited in claim 8 wherein said metallic adhesive comprises a layer that contains a material selected from the group consisting of:

vanadium;

niobium; and

tantalum.

16. The micromagnetic device as recited in claim 8 wherein said metallic adhesive comprises a layer that contains a material selected from the group consisting of:

chromium;

molybdenum; and

tungsten.

17. The micromagnetic device as recited in claim 8 wherein said metallic adhesive comprises a layer that contains a material selected from the group consisting of:

gold;

silver;

platinum;

palladium; and

copper.

18. The micromagnetic device as recited in claim 8 wherein said ferromagnetic core contains an alloy material.

19. The micromagnetic device as recited in claim 8 wherein said first insulative layer includes an organic polymer.