Inductor element, inductor element manufacturing method, and semiconductor device with inductor element mounted thereon

• US 8,339,230 B2
• Filed: 08/01/2007
• Issued: 12/25/2012
• Est. Priority Date: 08/01/2006
• Status: Active Grant

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: Renesas Electronics Corporation
• Inventors: Hijioka, Kenichiro, Tanabe, Akira, Hayashi, Yoshihiro
• Primary Examiner(s): Musleh, Mohamad
• Assistant Examiner(s): Chan, Tsz
• Application Number:
  US12/375,944
• Publication Number:
  US 20090315662A1
• Time in Patent Office: 1,973 Days
• Field of Search: 336/200, 336/232, 296/021
• US Class Current: 336/200
• CPC Class Codes: H01F 17/0013 with stacked layers
• CPC Class Codes: H01F 2017/002 Details of via holes for interconnecting the layers
• CPC Class Codes: H01F 2017/004 with the coil helically wound around an axis without a core
• CPC Class Codes: H01F 2017/0086 on semiconductor substrate
• CPC Class Codes: H01F 27/34 Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
• CPC Class Codes: H01F 41/041 Printed circuit coils apparatus or processes for manufacturing printed circuits in general H05K3/00
• CPC Class Codes: H01L 28/10 Inductors
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49071 by winding or coiling

Abstract

An inductor element is formed in a multiple layer lead structure including a lead, an insulative layer that insulates leads above and below, and a via provided in the insulative layer and connecting leads above and below wherein lead layers are multiply laminated layers, characterized in that: at least a portion of at least a pair of vertically adjacent leads are coiled leads; the coiled leads are connected in series, wherein current directions of vertically adjacent coiled leads are the same by a via provided on an end portion thereof, and form a serial inductance; and an inter-lead capacitance of the vertically adjacent coiled leads is larger than an inter-lead capacitance between other coiled leads formed in the same lead layer.

Claims

1. An inductor element formed in a multiple layer lead structure comprising:

a lead,

an insulative layer that insulates leads above and below, and

a via provided in the insulative layer and connecting leads above and below,

wherein lead layers are multiply laminated layers, comprising at least a portion of at least a pair of vertically adjacent leads which are coiled leads;

wherein the coiled leads are connected in series,

wherein at least two of the coiled leads comprise a shape having one wind;

wherein a shape having said one wind does not completely coil around and has a notch in a portion thereof;

wherein current directions of vertically adjacent coiled leads are the same by a via provided on an end portion thereof, and form a serial inductance; and

wherein an inter-lead capacitance of the vertically adjacent coiled leads is larger than an inter-lead capacitance between other coiled leads formed in the same lead layer.

2. The inductor element according to claim 1, wherein the vertically adjacent coiled leads are provided in not less than three lead layers, and not less than three layers of the coiled leads are connected in series by the via to make flow directions of currents the same.

3. The inductor element according to claim 1, wherein a lead width of the coiled leads is larger than a lead height of the coiled leads.

4. The inductor element according to claim 1, wherein spacing between other coiled leads formed in the same lead layer is equal to or larger than spacing between the vertically adjacent coiled leads.

5. The inductor element according to claim 4, wherein an effective relative dielectric constant of an insulative film that insulatively separates leads of the vertically adjacent coiled leads is larger than an effective relative dielectric constant of an insulative film that insulatively separates other coiled leads formed in the same lead layer.

6. The inductor element according to claim 1, wherein:

at least one of the coiled leads comprises a shape having two winds;

a coiled lead other than the coiled lead having two winds comprises a shape having the one wind; and

at least two coiled leads comprising the one-wind shape are formed in the same lead layer.

7. The inductor element according to claim 1, wherein the inductor element is formed by at least two layers of coiled leads.

8. The inductor element according to claim 1, wherein at least one of the coiled leads positioned in the uppermost layer comprises a shape having two winds in the same lead layer.

9. The inductor element according to claim 1, wherein at least one of the coiled leads positioned in the lowermost layer comprises a shape having two winds in the same lead layer.

10. The inductor element according to claim 1, wherein all of the lead heights of the coiled leads are substantially the same.

11. The inductor element according to claim 1, wherein at least one of draw out leads connected to an end portion of the coiled lead for electrically connecting to an external element is formed in a lead layer different than a lead layer wherein the coiled lead is formed.

12. The inductor element according to claim 11, further comprising a plurality of slits equidistantly formed with respect to each other in the coiled leads and the draw out lead.

13. The inductor element according to claim 1, wherein at least one of draw out leads connected to an end portion of the coiled lead for electrically connecting to an external element is formed by an elongation of any lead positioned at an outermost circumference of the coiled lead.

14. The inductor element according to claim 1, wherein distances between other coiled leads formed in the same lead layer are all substantially the same in the same lead layer.

15. The inductor element according to claim 1, wherein the coiled leads comprise a slit.

16. The inductor element according to claim 11, wherein the draw out lead comprises a slit.

17. The inductor element according to claim 1, wherein dummy metal is multiply formed in a lead layer wherein the coiled leads are formed, and a density of the dummy metal of a side proximal to the coiled leads is lower than a density of the dummy metal of a side distal to the coiled leads.

18. The inductors element according to claim 17, wherein the dummy metal is formed at the outside in a radial direction of the coiled leads, not inside in the radial direction of the coiled leads.

19. The inductor element according to claim 1, wherein dummy metal is multiply formed in a lead layer positioned in a layer above or below a lead layer wherein the coiled leads are formed, and a density of the dummy metal of a side proximal to the coiled leads is lower than a density of the dummy metal of a side distal to the coiled leads.

20. A semiconductor device comprising the inductor element according to claim 1.

21. The inductor element according to claim 1, wherein the coiled leads include inner circumference coiled leads and outer circumference coiled leads.

22. A semiconductor device wherein the inductor element recited in claim 1 and a transistor is connected with each other.

23. The semiconductor device according to claim 1, comprising a ground lead provided around the inductor element.

24. A semiconductor device comprising fixed potential leads having a mesh-like shape around the inductor element according to claim 1.

25. The inductor element according to claim 1, wherein said leads are completely covered by the insulative.

26. A semiconductor device comprising the inductor element according to claim 1, formed on a semiconductor substrate that is formed of a transistor.

27. A method for manufacturing an inductor element, comprising:

forming a lead layer wherein a coiled lead on an insulative film and a via that connects coiled leads are provided;

laminating lead layers wherein an inter-lead capacitance of the vertically adjacent coiled leads is larger than an inter-lead capacitance between other coiled leads formed in the same lead layer; and

forming a draw out lead for electrically connecting the coiled lead to an external element,

wherein at least two of the coiled leads comprise a shape having one wind; and

wherein a shape having said one wind does not completely coil around and has a notch in a portion thereof.