Integrated circuit inductors

• US 6,825,747 B2
• Filed: 03/18/2002
• Issued: 11/30/2004
• Est. Priority Date: 07/09/1999
• Status: Expired due to Term

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Ahn, Kie Y., Forbes, Leonard
• Primary Examiner(s): Nguyen, Viet Q.
• Application Number:
  US10/100,710
• Publication Number:
  US 20020095771A1
• Time in Patent Office: 988 Days
• Field of Search: 336/173, 336/186, 336/83, 336/84, 336/98, 336/147, 296/04, 296/05
• US Class Current: 336/173
• CPC Class Codes: H01F 17/0033 with the coil helically wound around a magnetic core
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H01F 37/00 Fixed inductances not covered by group H01F17/00
• CPC Class Codes: H01L 27/08 including only semiconductor components of a single kind
• CPC Class Codes: Y10S 257/924 with passive device, e.g. capacitor, or battery, as integral part of housing or housing element, e.g. cap
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49037 Using reference point/surface to facilitate measuring
• CPC Class Codes: Y10T 29/49069 Data storage inductor or core
• CPC Class Codes: Y10T 29/49071 by winding or coiling
• CPC Class Codes: Y10T 29/49073 by assembling coil and core
• CPC Class Codes: Y10T 29/49075 including permanent magnet or core

Abstract

The invention relates to an inductor comprising a plurality of interconnected conductive segments interwoven with a substrate. The inductance of the inductor is increased through the use of coatings and films of ferromagnetic materials such as magnetic metals, alloys, and oxides. The inductor is compatible with integrated circuit manufacturing techniques and eliminates the need in many systems and circuits for large off chip inductors. A sense and measurement coil, which is fabricated on the same substrate as the inductor, provides the capability to measure the magnetic field or flux produced by the inductor. This on chip measurement capability supplies information that permits circuit engineers to design and fabricate on chip inductors to very tight tolerances.

Claims

1. An integrated circuit comprising:

a substrate having a coating;

a circuit formed on the substrate; and

a conductive path operable for creating a magnetic field in the coating, and coupled to the circuit.

2. The integrated circuit of claim 1, wherein the coating includes a film of magnetic material.

3. The integrated circuit of claim 2, wherein the magnetic material includes a magnetic oxide.

4. The integrated circuit of claim 2, wherein the coating includes an insulating layer formed atop the film of magnetic material.

5. The integrated circuit of claim 1, wherein the substrate is a semiconductor.

6. The integrated circuit of claim 1, wherein the conductive path passes through the substrate.

7. An integrated circuit comprising:

a substrate having a first region with a coating formed in the first region;

a circuit formed on a second region of the substrate;

a conductive path formed through the substrate, the conductive path having a portion that traverses the coating and operable to create a magnetic field in the coating; and

wherein the circuit is coupled to the conductive path.

8. The integrated circuit of claim 7, wherein the conductive path is in the form of a coil having a rectangular cross-section.

9. The integrated circuit of claim 7, wherein the conductive path is in the form of a coil having a triangular cross-section.

10. The integrated circuit of claim 7, wherein the conductive path comprises a plurality of metal conductors.

11. The integrated circuit of claim 10, wherein the conductors include at least two conductors selected from the group of conductors consisting of:

gold, aluminum and copper.

12. An integrated circuit comprising:

a substrate;

a coating covering a portion of the substrate;

a conductive coil surrounding the portion of the substrate, with a portion of the coil traversing a portion of the coating so as to create a magnetic field in the portion of the coating; and

a circuit formed on the substrate and connected to the coil.

13. The integrated circuit of claim 12, wherein said portion of the coil is a magnetic film.

14. The integrated circuit of claim 13, wherein the coating includes an insulating layer covering the magnetic film.

15. The integrated circuit of claim 12, wherein the coil passes through holes formed in the substrate.

16. The integrated circuit of claim 12, further including a sense inductor formed on the substrate and magnetically coupled to the conductive coil.

17. The integrated circuit of claim 12, further including a sense inductor formed in the substrate and magnetically coupled to the conductive coil.

18. An integrated circuit comprising:

a semiconductor substrate having a magnetic film;

a circuit formed on the substrate spaced apart from the magnetic film;

a conductive coil formed in the substrate and magnetically coupled to the magnetic film to create a magnetic field in the magnetic film;

leads connected to the coil; and

wherein the circuit is electrically connected to the leads.

19. The integrated circuit of claim 18, wherein the semiconductor substrate comprises one of silicon, germanium, gallium arsenide and silicon carbide.

20. The integrated circuit of claim 18, wherein the magnetic film includes nickel and iron.

21. The integrated circuit of claim 18, wherein the coil comprises at least one of gold, copper and aluminum.

22. The integrated circuit of claim 18, wherein the magnetic film is covered by an insulating layer.

23. An integrated circuit comprising:

a substrate having first and second sides;

first and second magnetic films formed the first and second sides, respectively;

a circuit formed on the first side of the substrate; and

a conductive path traversing the first and second magnetic films and passing through the substrate, the conductive path operable to create a magnetic field in the first and second magnetic films; and

wherein the circuit is connected to the conductive path.

24. The integrated circuit of claim 23, wherein the conductive path is in the form of a coil passing through holes formed in the substrate that connect the first and second sides.

25. The integrated circuit of claim 24, wherein the first and second magnetic films include nickel.

26. The integrated circuit of claim 25, wherein the first and second magnetic films include iron.

27. The integrated circuit of claim 26, wherein the first and second magnetic films are covered by respective first and second insulating layers.

28. The integrated circuit of claim 23, wherein the conductive path comprises at least one of gold, aluminum and copper.

29. The integrated circuit of claim 28, wherein the conductive path includes first segments comprising copper and second segments comprising aluminum.

30. An integrated circuit comprising:

a substrate having a planar surface with a coating formed on a portion of the planar surface;

a conductive path in the form of a triangular coil having first segments that traverse the coating, the triangular coil designed to create a magnetic field in a portion of the coating when an electrical current passes through the coil; and

a circuit formed on the substrate and operatively coupled to coil.

31. The integrated circuit of claim 30, wherein the triangular coil includes second segments that pass through the substrate and connect to the first segments.

32. The integrated circuit of claim 30, wherein the coating includes a magnetic film.

33. The integrated circuit of claim 30, wherein the coating includes an insulating layer.

34. An integrated circuit comprising:

a planar substrate;

a coating formed on a portion of the planar substrate;

a coil having first segments passing through the substrate adjacent the coating and second segments traversing the coating and connecting the first segments, the coil operative to form a magnetic field in the coating; and

a circuit formed integral with the substrate and operatively connected to the coil.

35. The integrated circuit of claim 34, wherein the coil has a rectangular cross-section.

36. The integrated circuit of claim 34, wherein the coating includes a magnetic film.

37. The integrated circuit of claim 34, further including a sense inductor formed integral with the substrate and magnetically coupled to the coil.