Magnetic Film Enhanced Inductor

• US 20100259349A1
• Filed: 04/09/2009
• Published: 10/14/2010
• Est. Priority Date: 04/09/2009
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Li, Xia
• Application Number:
  US12/420,869
• Publication Number:
  US 20100259349A1
• Time in Patent Office: Days
• US Class Current: 336/200
• CPC Class Codes: H01F 19/04 Transformers or mutual inductances suitable for handling frequencies considerably beyond the audio range resonant circuits H03H
• 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 28/10 Inductors
• 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 2924/3011 Impedance
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor

Abstract

An integrated magnetic film enhanced transformer and a method of forming an integrated magnetic film enhanced transformer are disclosed. The integrated magnetic film enhanced transformer includes an transformer metal having a first portion and a second portion, a top metal coupled to the transformer metal, a bottom metal coupled to the transformer metal, and an isolation film disposed between the first portion and the second portion of the transformer metal. The isolation film includes a magnetic material that can enhance a magnetic flux density B of the transformer, increase an electromotive force (EMF) of the transformer, and increase a magnetic permeability of the transformer.

Claims

1. A transformer comprising:

a transformer metal having a first portion and a second portion; and

an isolation film interposing the first portion and the second portion of the transformer metal,

wherein the isolation film includes a magnetic material.

2. The integrated magnetic film enhanced transformer according to claim 1, wherein the magnetic material is a magnetic film.

3. The transformer according to claim 1, further comprising:

a top metal coupled to the transformer metal; and

a bottom metal coupled to the transformer metal.

4. The transformer according to claim 3, wherein a via interconnect couples the top metal to the transformer metal.

5. The transformer according to claim 3, wherein a via interconnect couples the bottom metal to the transformer metal.

6. The transformer according to claim 1, wherein the transformer is a cross comb type planar transformer.

7. The transformer according to claim 1, wherein the transformer is a serpent type planar self coupling transformer.

8. The transformer according to claim 1, wherein the transformer is a circular type planar self coupling transformer.

9. The transformer according to claim 1, wherein the transformer is a three-dimensional circular self coupling transformer.

10. The transformer according to claim 9, wherein the magnetic material extends along a longitudinal axis of the three-dimensional circular self coupling transformer.

11. The transformer according to claim 1 integrated in at least one semiconductor die.

12. The transformer according to claim 1, further comprising an electronic device, selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, and a computer, into which the transformer is integrated.

13. A transformer comprising:

a substrate;

a transformer metal having a plurality of turns formed on the substrate; and

a magnetic material disposed between adjacent portions of the plurality of turns of the transformer metal.

14. The transformer according to claim 13, wherein the magnetic material is a magnetic film.

15. The transformer according to claim 13, further comprising:

a top metal coupled to the transformer metal; and

a bottom metal coupled to the transformer metal.

16. The transformer according to claim 13 integrated in at least one semiconductor die.

17. The transformer according to claim 13, further comprising an electronic device, selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, and a computer, into which the transformer is integrated.

18. An integrated magnetic film enhanced three-dimensional circular self coupling transformer comprising:

a transformer metal having a plurality of top metal portions, a plurality of via interconnects, and a plurality of bottom metal portions extending along a longitudinal axis of the transformer; and

a magnetic material disposed between adjacent portions of the transformer metal.

19. The transformer according to claim 18, wherein the magnetic material is a magnetic film.

20. The transformer according to claim 18, wherein the magnetic material extends along the longitudinal axis of the transformer.

21. The transformer according to claim 18, wherein the plurality of top metal portions, the plurality of via interconnects, and the plurality of bottom metal portions form a plurality of U-shaped, interconnected elements extending along the longitudinal axis of the transformer.

22. The transformer according to claim 18, wherein a first top metal of the plurality of top metal portions is coupled in series to a first end of a first via interconnect of the plurality of via interconnects,

wherein a second end of the first via interconnect is coupled in series to a first end of a first bottom metal of the plurality of bottom metal portions,

wherein a second end of the first bottom metal is coupled in series to a first end of a second via interconnect of the plurality of via interconnects, and

wherein a second end of the second via interconnect is coupled in series to a first end of a second top metal of the plurality of top metal portions.

23. The transformer according to claim 22, wherein the first top metal is parallel to the second top metal,

wherein the first via interconnect is parallel to the second via interconnect,

wherein the first via interconnect and the second via interconnect are perpendicular to the first top metal and the second top metal,

wherein the first via interconnect and the second via interconnect are perpendicular to the first bottom metal, and

wherein the first bottom metal is perpendicular to each of the first via interconnect, the second via interconnect, the first top metal, and the second top metal.

24. The transformer according to claim 18 integrated in at least one semiconductor die.

25. The transformer according to claim 18, further comprising an electronic device, selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, and a computer, into which the transformer is integrated.

26. A method of forming a transformer, the method comprising:

depositing and patterning a transformer metal having a first portion and a second portion; and

depositing and patterning a magnetic material between the first portion and the second portion of the transformer metal.

27. The method according to claim 26, wherein the magnetic material is a magnetic film.

28. The method according to claim 26, wherein the magnetic material is a shape anisotropic magnetic film.

29. The method according to claim 26, further comprising:

forming a bottom metal coupled to the transformer metal; and

forming a top metal coupled to the transformer metal.

30. The method according to claim 26, wherein a thickness of the magnetic material is selected to reduce an eddy current and a skin effect inside the magnetic material to reduce magnetic field loss.

31. The method according to claim 26, further comprising:

performing a magnetic anneal process to align a magnetic field axis of the transformer along an easy axis of the magnetic material.

32. The method according to claim 26, further comprising:

depositing a cap layer on the transformer metal to self-align the magnetic material between the first portion and the second portion of the transformer metal.

33. The method according to claim 26, wherein the transformer is applied in an electronic device, selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, and a computer, into which the transformer is integrated.

34. A method of forming a transformer, the method comprising:

depositing and patterning a bottom metal using a metal deposit/photo/etching process;

depositing a first inter layer dielectric (ILD) on the first metal and performing a chemical mechanical planarization (CMP) process on the inter layer dielectric;

depositing a bottom cap film on the first inter layer dielectric (ILD);

depositing an transformer metal on the bottom cap film and patterning the transformer metal using a photo/etching process;

depositing a top cap film above the transformer metal and performing a chemical mechanical planarization (CMP) process on the top cap film;

performing a photo/etching process to the top cap film to form a plurality of holes between portions of the transformer metal;

depositing a magnetic material over the top cap film and the plurality of holes and etching the magnetic material back to a top of the top cap film such that the magnetic material is interposed between the portions of the transformer metal;

depositing a second inter layer dielectric (ILD) above the magnetic material and performing a chemical mechanical planarization (CMP) process on the second inter layer dielectric (ILD); and

performing a vertical magnetic anneal to align a magnetic field axis of the transformer along an easy axis of the magnetic material.

35. The method according to claim 34, further comprising:

patterning a first via opening in the first inter layer dielectric (ILD) using a photo/etching process and filling the first via opening with a metal to form a bottom via interconnect that couples the transformer metal to the bottom metal.

36. The method according to claim 34, further comprising:

depositing and patterning a top metal above the second inter layer dielectric (ILD) using a metal deposit/photo/etching process; and

patterning a second via opening in the second inter layer dielectric (ILD) using a photo/etching process and filling the second via opening with a metal to form a top via interconnect that couples the transformer metal to the top metal.

37. The method according to claim 34, wherein the magnetic material is a magnetic film.

38. The method according to claim 34, wherein the magnetic material is a shape anisotropic magnetic film.

39. The method according to claim 34, wherein a thickness of the magnetic material is selected to reduce an eddy current and a skin effect inside the magnetic material to reduce magnetic field loss.

40. The method according to claim 34, wherein the transformer is applied in an electronic device, selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, and a computer, into which the transformer is integrated.

41. A method of forming a transformer, the method comprising:

depositing and patterning a bottom metal using a dual damascene process;

depositing a first inter layer dielectric (ILD) on the first metal;

depositing a bottom cap film on the first inter layer dielectric (ILD);

depositing a second inter layer dielectric (ILD) on the bottom cap film;

forming a plurality of trenches in the second inter layer dielectric (ILD) using photolithography and etching techniques;

plating a copper layer over at least the plurality of trenches and polishing the copper layer down to the surface of the second inter layer dielectric (ILD) to form an transformer metal;

depositing a top cap film above the second inter layer dielectric (ILD) and the transformer metal;

forming a plurality of holes in the top cap film and the second inter layer dielectric (ILD) using photolithography and etching techniques;

depositing a magnetic material layer over at least the plurality of holes;

depositing a third inter layer dielectric (ILD) above the magnetic material and performing a chemical mechanical planarization (CMP) process on the third inter layer dielectric (ILD); and

performing a vertical magnetic anneal to align a magnetic field axis of the transformer along an easy axis of the magnetic material.

42. The method according to claim 41, further comprising:

patterning a first via opening in the first inter layer dielectric (ILD) using a damascene process and filling the first via opening with a metal to form a bottom via interconnect that couples the transformer metal to the bottom metal.

43. The method according to claim 41, further comprising:

depositing and patterning a top metal above the third inter layer dielectric (ILD) using a damascene process; and

patterning a second via opening in the third inter layer dielectric (ILD) using a damascene process and filling the second via opening with a metal to form a top via interconnect that couples the transformer metal to the top metal.

44. The method according to claim 41, wherein the magnetic material is a magnetic film.

45. The method according to claim 41, wherein the magnetic material is a shape anisotropic magnetic film.

46. The method according to claim 41, wherein a thickness of the magnetic material is selected to reduce an eddy current and a skin effect inside the magnetic material to reduce magnetic field loss.

47. The method according to claim 41, wherein the transformer is applied in an electronic device, selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, and a computer, into which the transformer is integrated.

48. A transformer comprising:

transformer means for generating a magnetic field, the transformer means having a first portion and a second portion; and

isolating means for magnetically isolating the first portion and the second portion of the transformer means, the isolating means interposing the first portion and the second portion of the transformer means,

wherein the isolating means includes a magnetic material.

49. The integrated magnetic film enhanced transformer according to claim 48, wherein the magnetic material is a magnetic film.

50. The transformer according to claim 48, further comprising:

top metal means for electrically connecting the transformer coupled to the transformer means; and

bottom metal means for electrically connecting the transformer coupled to the transformer means.

51. The transformer according to claim 50, further comprising:

first via interconnecting means for coupling the top metal means to the transformer means.

52. The transformer according to claim 50, further comprising:

second via interconnecting means for coupling the bottom metal means to the transformer means.

53. The transformer according to claim 48, wherein the transformer is a cross comb type planar transformer.

54. The transformer according to claim 48, wherein the transformer is a serpent type planar self coupling transformer.

55. The transformer according to claim 48, wherein the transformer is a circular type planar self coupling transformer.

56. The transformer according to claim 48, wherein the transformer is a three-dimensional circular self coupling transformer.

57. The transformer according to claim 56, wherein the magnetic material extends along a longitudinal axis of the three-dimensional circular self coupling transformer.

58. The transformer according to claim 48 integrated in at least one semiconductor die.

59. The transformer according to claim 48, further comprising an electronic device, selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, and a computer, into which the transformer is integrated.

60. A method of forming a transformer, the method comprising:

step for depositing and patterning a transformer metal having a first portion and a second portion; and

step for depositing and patterning a magnetic material between the first portion and the second portion of the transformer metal.

61. The method according to claim 60, wherein the magnetic material is a magnetic film.

62. The method according to claim 60, wherein the magnetic material is a shape anisotropic magnetic film.

63. The method according to claim 60, further comprising:

step for forming a bottom metal coupled to the transformer metal; and

step for forming a top metal coupled to the transformer metal.

64. The method according to claim 60, wherein a thickness of the magnetic material is selected to reduce an eddy current and a skin effect inside the magnetic material to reduce magnetic field loss.

65. The method according to claim 60, further comprising:

performing a magnetic anneal process to align a magnetic field axis of the transformer along an easy axis of the magnetic material.

66. The method according to claim 60, further comprising:

step for depositing a cap layer on the transformer metal to self-align the magnetic material between the first portion and the second portion of the transformer metal.

67. The method according to claim 60, wherein the transformer is applied in an electronic device, selected from the group consisting of a set top box, music player, video player, entertainment unit, navigation device, communications device, personal digital assistant (PDA), fixed location data unit, and a computer, into which the transformer is integrated.