Method of fabricating a miniaturized integrated circuit inductor and transformer fabrication

• US 20020097129A1
• Filed: 03/25/2002
• Published: 07/25/2002
• Est. Priority Date: 02/16/2000
• Status: Abandoned Application

• Current Assignee: Johnson, F. Scott
• Original Assignee: Johnson, F. Scott
• Inventors: Johnson, F. Scott
• Application Number:
  US10/105,690
• Publication Number:
  US 20020097129A1
• Time in Patent Office: Days
• US Class Current: 336/200
• CPC Class Codes: H01F 17/0006 Printed inductances printed coils for dynamo-electric machines H02K3/26; printed circuits H05K
• CPC Class Codes: H01F 17/0033 with the coil helically wound around a magnetic core
• CPC Class Codes: H01F 41/046 structurally combined with ferromagnetic material
• CPC Class Codes: H01L 27/08 including only semiconductor components of a single kind
• CPC Class Codes: H01L 28/10 Inductors

Abstract

A method for fabricating inductors and transformers on integrated circuits. A magnetic material is formed on the semiconductor substrate. The magnetic material comprises a suspension of magnetic material in an insulator. A metal film is formed that forms at least one coil around the magnetic material forming an inductor structure. Two adjacent coils can be linked with the magnetic material to form a transformer.

Claims

1. A method of forming an inductor in a semiconductor substrate with an upper surface, said method comprising the steps of:

forming a magnetic film on said upper surface of said semiconductor substrate;

patterning said second magnetic film using photolithography;

forming a metal film on said upper surface of said semiconductor substrate; and

patterning said metal film such that said metal film forms at least one coil around said magnetic film;

2. The method of claim 1, wherein said magnetic film comprises a material selected from the group consisting of:

Ni, Ni-Cu-Cr, Mn-Zn-Ferrite, and any combination thereof.

3. The method of claim 1 wherein said magnetic film comprises a stack of alternating layers of a magnetic film and an insulating film.

4. The method of claim 1 wherein said magnetic film comprises a suspension of a magnetic material in an insulating material.

5. A method of forming an inductor in a semiconductor substrate with an upper surface, said method comprising the steps of:

forming a first magnetic film on said upper surface of said semiconductor substrate wherein said first magnetic film has a upper surface;

forming a first insulating layer on said upper surface of said first magnetic film wherein said first insulating layer has an upper surface;

forming a second magnetic film on said upper surface of said first insulating layer;

patterning said second magnetic film using photolithography;

forming a metal film on the upper surface of said second first insulating layer;

patterning said metal film such that said metal film forms at least one coil around said second magnetic film;

forming a second insulating layer with an upper surface on said upper surface of said first insulating layer wherein said second insulating layer completely encases said second magnetic film and said metal film; and

forming a third magnetic film on said upper surface of said second insulating layer.

6. The method of claim 5, wherein said first magnetic film comprises a material selected from the group consisting of:

Ni, Ni-Cu-Cr, Mn-Zn-Ferrite, and any combination thereof.

7. The method of claim 5, wherein said second magnetic film comprises a material selected from the group consisting of:

Ni, Ni-Cu-Cr, Mn-Zn-Ferrite, and any combination thereof.

8. The method of claim 5, wherein said third magnetic film comprises a material selected from the group consisting of:

Ni, Ni-Cu-Cr, Mn-Zn-Ferrite, and any combination thereof.

9. The method of claim 5 wherein said first magnetic film comprises a stack of alternating layers of a magnetic film and an insulating film.

10. The method of claim 5 wherein said second magnetic film comprises a stack of alternating layers of a magnetic film and an insulating film.

11. The method of claim 5 wherein said third magnetic film comprises a stack of alternating layers of a magnetic film and an insulating film.

12. The method of claim 5 wherein said first magnetic film comprises a suspension of magnetic material in an insulating material.

13. The method of claim 5 wherein said second magnetic film comprises a suspension of magnetic material in an insulating material.

14. The method of claim 5 wherein said third magnetic film comprises a suspension of magnetic material in an insulating material.

16. The method of claim 15 wherein said magnetic film comprises a suspension of magnetic material in an insulating material.

17. The method of claim 15 wherein said magnetic film comprises a stack of alternating layers of a magnetic film and an insulating film.

18. The method of claim 15, wherein said magnetic film comprises a material selected from the group consisting of:

Ni, Ni-Cu-Cr, Mn-Zn-Ferrite, and any combination thereof.

20. The integrated circuit inductor of claim 18 further comprising;

a second magnetic film on said upper surface of said insulator layer; and

a third magnetic film on said lower surface of said insulator layer.

21. The integrated circuit of claim 19 wherein said first magnetic film comprises a suspension of magnetic material in a second insulator.

15. A method of forming an inductor in a semiconductor substrate with an upper surface, said method comprising:

forming a first metal film on said upper surface of said semiconductor substrate;

patterning said first metal film;

forming a magnetic layer above said first metal film;

patterning said magnetic film;

forming a second metal film above said magnetic film;

patterning said second metal film; and

forming electrically conducting contacts between said first metal film and said second metal film wherein said first metal film, said second metal film, and said electrically conducting contacts form at least one coil around said magnetic film.

19. An integrated circuit inductor in a semiconductor substrate comprising:

an insulator layer with an upper surface and a lower surface;

a first magnetic material contained within said insulator; and

a metal film contained within said insulator forming at least one coil around said first magnetic material.

22. An integrated circuit inductive coil in a semiconductor substrate comprising:

a first metal film with a first pattern;

a magnetic layer above said first metal film;

a second metal film above said magnetic film with a second pattern;

a plurality of electrically conducting contacts between said first metal film and said second metal film wherein said first metal film, said second metal film, and said electrically conducting contacts form at least one coil around said magnetic film.

25. The method of claim 24, wherein said magnetic film comprises a material selected from the group consisting of:

Ni, Ni-Cu-Cr, Mn-Zn-Ferrite, and any combination thereof.

26. The method of claim 24 wherein said magnetic film comprises a stack of alternating layers of a magnetic film and an insulating film.

27. The method of claim 24 wherein said magnetic film comprises a suspension of a magnetic material in an insulating material.

23. An integrated circuit transformer in a semiconductor substrate comprising:

a first metal film with a first pattern;

a continuous magnetic layer above said first metal film;

a second metal film above said magnetic film with a second pattern;

a plurality of electrically conducting contacts between said first metal film and said second metal film wherein said first metal film, said second metal film, and said electrically conducting contacts form two adjacent coils with each coil having at least one turn around said magnetic film.

24. A method of forming an inductor in a semiconductor substrate with an upper surface, said method comprising the steps of:

forming a magnetic structure on said semiconductor substrate; and

forming a metal structure on said upper surface of said semiconductor substrate such that a magnetic flux is induced in said magnetic film.

28. A method of forming an inductor in a semiconductor substrate with a upper surface, said method comprising the steps of:

forming a first magnetic structure on said semiconductor substrate;

forming a first insulating layer on said first magnetic film;

forming a second magnetic structure on said first insulating layer;

forming a metal structure on said second first insulating layer such that said metal film induces a magnetic flux in said second magnetic film;

forming a second insulating layer with an upper surface on said first insulating layer wherein said second insulating layer encases said second magnetic film and said metal film; and

forming a third magnetic film on said second insulating layer.