Integrated circuit inductors

• US 6,910,260 B2
• Filed: 03/18/2002
• Issued: 06/28/2005
• 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:
  US10/100,715
• Publication Number:
  US 20020095772A1
• Time in Patent Office: 1,198 Days
• Field of Search: 296/04, 296/05, 296/06, 296/021, 336/200, 336/223
• US Class Current: 29/604
• 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 inductor comprising:

a substrate having a plurality of holes and a plurality of surfaces;

a conductive material having a conductivity of at least copper and filling at least three of the plurality of holes to form a plurality of conductive segments; and

a plurality of conductive interconnects formed on at least one of the plurality of surfaces and coupling to the plurality of conductive segments to form a continuous conductive coil.

2. The inductor of claim 1, wherein the conductive material includes copper or gold.

3. The inductor of claim 1, wherein the continuous conductive coil has a triangular cross-section.

4. The inductor of claim 1, wherein the substrate includes one or more magnetic films at least partially surrounded by the coil.

5. The inductor of claim 4, wherein the one or more magnetic films comprises a magnetic oxide.

6. The inductor of claim 1, further including at least two leads connected to the coil.

7. The inductor of claim 6, further including a circuit connected to the at least two leads.

8. An inductor comprising:

a substrate having a plurality of holes connecting opposing substrate surfaces;

a conductive material having a conductivity equal to or greater than that of copper filling the plurality of holes to form a plurality of conductive segments; and

a plurality of conductive interconnects coupled to the plurality of conductive segments to form a continuous conductive coil that surrounds the opposing substrate surfaces.

9. The inductor of claim 8, further including a magnetic film formed between one of the substrate opposing surfaces and the plurality of conductive interconnects.

10. The inductor of claim 9, wherein the magnetic film comprises a magnetic oxide.

11. The inductor of claim 8, further including two or more leads connected to the coil.

12. The inductor of claim 11, further including a circuit connected to the two or more leads.

13. The inductor of claim 9, further including an insulator layer covering the magnetic film.

14. The inductor of claim 8, wherein the coil has a rectangular cross-section.

15. The inductor according to claim 8, wherein the conductive material has a conductivity equal to or greater than that of copper.

16. The inductor of claim 15, wherein the conductive material comprises copper or gold.

17. An inductor comprising:

a semiconductor substrate having a plurality of through holes and a plurality of layers;

copper filling the through holes to form a plurality of copper segments; and

a plurality of conductive interconnects coupled to the plurality of copper segments to form a continuous conductive coil surrounding the substrate and at least one of the plurality of layers.

18. The inductor of claim 17, wherein the plurality of layers includes a magnetic film.

19. The inductor of claim 18, wherein the plurality of layers includes an insulating layer covering the magnetic film.

20. The inductor of claim 18, wherein the magnetic film is surrounded by the conductive coil.

21. The inductor of claim 17, wherein the conductive interconnects are copper.

22. An inductor comprising:

a substrate having a plurality of holes connecting two of a plurality of substrate surfaces;

one or more layers of magnetic material formed on at least one of the substrate surfaces;

a conductive material filling the plurality of holes to form a corresponding plurality of conductive segments, the conductive material having a conductivity equal to or greater than that of copper; and

a plurality of conductive interconnects coupled to the plurality of conductive segments to form a continuous conductive coil that surrounds the substrate surfaces and at least one of the one or more layers.

23. The inductor of claim 22, further including at least two conductive leads connected to the coil.

24. The inductor of claim 23, further including a circuit connected to the at least two conductive leads.

25. The inductor of claim 24, wherein the circuit includes memory cells.

26. The inductor of claim 22, wherein the conductive material is copper.

27. The inductor of claim 22, wherein the conductive material is gold.