COIL COMPONENT AND METHOD FOR PRODUCING SAME

• US 20130222101A1
• Filed: 10/14/2011
• Published: 08/29/2013
• Est. Priority Date: 10/21/2010
• Status: Active Grant

• Current Assignee: TDK Corporation
• Original Assignee: TDK Corporation
• Inventors: Ito, Tomokazu, Ohkubo, Hitoshi, Maeda, Yoshihiro, Morita, Makoto, Anbo, Toshiyuki, Ohta, Manabu, Tonoyama, Kyohei
• Granted Patent: US 9,236,171 B2
• Time in Patent Office: Days
• US Class Current: 336/83
• CPC Class Codes: H01F 17/04 with magnetic core
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 27/255 made from particles H01F27/26 takes precedence
• CPC Class Codes: H01F 27/324 Insulation between coil and core, between different winding sections, around the coil; Other insulation structures
• CPC Class Codes: H01F 3/08 made from powder powder coatings on sheets H01F3/02; on strips or ribbons H01F3/04; on wires H01F3/06
• CPC Class Codes: H01F 41/04 for manufacturing coils coils for transformer or inductances H01F27/28
• CPC Class Codes: H01F 5/003 Printed circuit coils
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49075 including permanent magnet or core

Abstract

A coil component includes: an insulating resin layer provided between a first planar spiral conductor formed on a back surface of a first substrate and a second planer spiral conductor formed on a back surface of a second substrate; an upper core covering a third second planer spiral conductor formed on a front surface of the first substrate on which the insulating resin layer is formed; and a lower core covering a fourth planer spiral conductor formed on a front surface of the second substrate on which the insulating resin layer is formed. One of the upper and lower cores is formed of a metal-magnetic-powder-containing resin. The coil component includes connecting portions disposed respectively at center and outside portions of each of the first and second substrates so as to physically connect the upper and lower cores.

Claims

1. A coil component comprising:

a first substrate;

a second substrate disposed such that a top surface of the second substrate faces a back surface of the first substrate;

first and second planar spiral conductors formed, by electrolytic plating, on the top and back surfaces of the first substrate, respectively, an inner peripheral end of the first planar spiral conductor and an inner peripheral end of the second planar spiral conductor being connected to each other through a first through hole conductor penetrating the first substrate;

third and fourth planar spiral conductors formed, by electrolytic plating, on the top and back surfaces of the second substrate, respectively, an inner peripheral end of the third planar spiral conductor and an inner peripheral end of the fourth planar spiral conductor being connected to each other through a second through hole conductor penetrating the second substrate;

an insulating layer formed between the second planer spiral conductor and third planar spiral conductor;

a first external electrode connected to an outer peripheral end of the first planar spiral conductor and an outer peripheral end of the fourth planar spiral conductor;

a second external electrode connected to an outer peripheral end of the second planar spiral conductor and an outer peripheral end of the third planar spiral conductor;

a first insulating resin layer covering the first planar spiral conductor;

an upper core covering the top surface of the first substrate on which the first insulating resin layer is formed;

a second insulating resin layer covering the second planar spiral conductor; and

an lower core covering the back surface of the second substrate on which the second insulating resin layer is formed, wherein

at least one of the upper and lower cores is formed of a metal-magnetic-powder-containing resin, and

the coil component further includes connecting portions disposed respectively at center and outside portions of each of the first and second substrates so as to physically connect the upper and lower cores.

2. The coil component according to claim 1, wherein

film thicknesses of innermost and outermost turns of each of the second and third planar spiral conductors are larger than film thicknesses of the other turns of each of the second and third planar spiral conductors, and

a top surface of the innermost turns of the second planer spiral conductor and a top surface of the innermost turn of the third planar spiral conductor penetrate the insulating layer to be brought into contact with each other,

a top surface of the outermost turn of the second planer spiral conductor and a top surface of the outermost turn of the third planar spiral conductor penetrate the insulating layer to be brought into contact with each other, and

top surfaces of turns of the second planar spiral conductor other than the innermost and outermost turns and top surfaces of turns of the third planar spiral conductor other than the innermost and outermost turns are electrically isolated from each other by the insulating layer.

3. A coil component comprising:

at least one insulating substrate;

a spiral conductor formed on at least one main surface of the insulating substrate,

an upper core covering the one main surface of the insulating substrate; and

a lower core covering the other main surface of the insulating substrate, wherein

at least one of the upper and lower cores is formed of a metal-magnetic-powder-containing resin, and

the coil component further includes connecting portions disposed respectively at center and outside portions of the insulating substrate so as to physically connect the upper and lower cores.

4. The coil component according to claim 3, wherein both the upper and lower cores are formed of the metal-magnetic-powder-containing resin.

5. The coil component according to claim 3, wherein one of the upper and lower cores is formed of the metal-magnetic-powder-containing resin and the other one of the upper and lower cores is formed of a ferrite substrate.

6. The coil component according to claim 3, wherein the connecting portions each connecting the upper and lower cores are disposed at a center portion and respective four corner portions of the insulating substrate.

7. The coil component according to claim 6, wherein the connecting portions at the respective four corners are disposed in contact with an edge of each of the corner portions of the insulating substrate.

8. The coil component according to claim 6, wherein the connecting portions at the respective four corners are disposed inward of an edge of each of the corner portions of the insulating substrate.

9. The coil component according to claim 3, further comprising a plating conductor pattern formed on the one main surface of the insulating substrate, wherein

one end of the plating conductor pattern is electrically connected to the spiral conductor,

the other end of the plating conductor pattern extends up to the edge of the insulating substrate, and

the plating conductor pattern, at the mass production time when a plurality of coil components are formed on a single substrate, constitutes a part of a short-circuiting pattern electrically connecting the spiral conductors of adjacent coil components.

10. The coil component according to claim 3, further comprising:

a pair of terminal electrodes formed on outer peripheral surfaces of a laminated body constituted by the insulating substrate and the upper and lower cores; and

an insulating film covering surfaces of the upper and lower cores, wherein

the insulating film is interposed between the pair of terminal electrodes and the upper and lower cores.

11. The coil component according to claim 10, wherein the insulating film is an insulating layer obtained by chemical conversion treatment using iron phosphate, zinc phosphate, or zirconia dispersed solution.

12. The coil component according to claim 11, wherein the insulating film is formed of an Ni-based-ferrite-containing resin.

13. The coil component according to claim 3, comprising a plurality of the insulating substrates, wherein

the plurality of insulating substrates are preferably laminated substantially without intervention of the metal-magnetic-powder-containing resin, and

the spiral conductors formed on the respective insulating substrates are connected in parallel or in series through the pair of terminal electrodes.

14. A coil component comprising:

a first substrate;

a second substrate disposed such that a top surface of the second substrate faces to a back surface of the first substrate;

first and second planar spiral conductors formed, by electrolytic plating, on the top and back surfaces of the first substrate, respectively, an inner peripheral end of the first planar spiral conductor and an inner peripheral end of the second planar spiral conductor being connected to each other through a first through hole conductor penetrating the first substrate;

third and fourth planar spiral conductors formed, by electrolytic plating, on the top and back surfaces of the second substrate, respectively, an inner peripheral end of the third planar spiral conductor and an inner peripheral end of the fourth planar spiral conductor being connected to each other through a second through hole conductor penetrating the second substrate;

an insulating layer formed between the second planer spiral conductor and third planar spiral conductor;

a first external electrode connected to an outer peripheral end of the first planar spiral conductor and an outer peripheral end of the fourth planar spiral conductor; and

a second external electrode connected to an outer peripheral end of the second planar spiral conductor and an outer peripheral end of the third planar spiral conductor.

15. The coil component according to claim 14, wherein

film thicknesses of innermost and outermost turns of each of the second and third planar spiral conductors are larger than those of the other turns of each of the second and third planar spiral conductors,

a top surface of the innermost turn of the second planer spiral conductor and a top surface of the innermost turn of the third planar spiral conductor penetrate the insulating layer to be brought into contact with each other,

a top surface of the outermost turn of the second planer spiral conductor and a top surface of the outermost turn of the third planar spiral conductor penetrate the insulating layer to be brought into contact with each other, and

top surfaces of turns of the second planar spiral conductor other than the innermost and outermost turns and top surfaces of turns of the third planar spiral conductor other than the innermost and outermost turns are electrically isolated from each other by the insulating layer.

16. The coil component according to claim 14, wherein

the film thicknesses of the turns of the second planar spiral conductors are made uniform, and

the film thicknesses of the turns of the third planar spiral conductors are made uniform.

17. The coil component according to claim 16, wherein

the film thicknesses of the turns of the first planar spiral conductor are made uniform, and

the film thicknesses of the turns of the fourth planar spiral conductor are made uniform.

18. The coil component according to claim 14, further comprising:

an insulating resin layer covering the first and fourth planar spiral conductors, and

a metal-magnetic-powder-containing resin layer covering the top surface of the first substrate and the back surface of the second substrate on each of which the insulating resin layer is formed.

19. A manufacturing method of a coil component comprising:

a conductor formation step of forming first and second planar spiral conductors on respective top and back surfaces of a first substrate by electrolytic plating, forming a first through hole conductor penetrating the first substrate so as to connect an inner peripheral end of the first planar spiral conductor and an inner peripheral end of the second planar spiral conductor, forming third and fourth planar spiral conductors on respective top and back surfaces of the second substrate by the electrolytic plating, and forming a second through hole conductor penetrating the second substrate so as to connect an inner peripheral end of the third planar spiral conductor and an inner peripheral end of the fourth planar spiral conductor;

an insulating resin layer formation step of forming a first insulating resin layer covering top surfaces of turns of the second planar spiral conductor other than at least the outermost and innermost turns and forming a second insulating resin layer covering top surfaces of turns of the third planar spiral conductor other than at least the outermost and innermost turns;

a lamination step of laminating the first and second substrates such that the back surface of the first substrate and the top surface of the second substrate face each other; and

an external electrode formation step of forming a first external electrode connecting an outer peripheral end of the first planar spiral conductor and an outer peripheral end of the fourth planar spiral conductor and a second external electrode connecting an outer peripheral end of the second planar spiral conductor and an outer peripheral end of the third planar spiral conductor.

20. The manufacturing method of a coil component according to claim 19, wherein

the first insulating resin layer covers also the top surfaces of the outermost and innermost turns of the second planar spiral conductor,

the second insulating resin layer covers also the top surfaces of the outermost and innermost turns of the third planar spiral conductor,

the insulating resin layer formation step includes a grinding step of applying grinding to the surface of the first insulating resin layer to expose the top surfaces of the outermost and innermost turns of the second planar spiral conductor from the surface of the first insulating resin layer and applying grinding to the surface of the second insulating resin layer to expose the top surfaces of the outermost and innermost turns of the third planar spiral conductor from the surface of the second insulating resin layer, and

the lamination step laminates the first and second substrates in a state where the top surfaces of the outermost and innermost turns of the second planar spiral conductor are exposed from the surface of the first insulating resin layer and where the top surfaces of the outermost and innermost turns of the third planar spiral conductor are exposed from the surface of the second insulating resin layer.

21. The manufacturing method of a coil component according to claim 19, wherein

the insulating resin layer formation step including:

a grinding step of applying grinding to the surface of the first insulating resin layer to expose the top surfaces of respective turns of the second planar spiral conductor from the surface of the first insulating resin layer and applying grinding to the surface of the second insulating resin layer to expose the top surfaces of respective turns of the third planar spiral conductor from the surface of the second insulating resin layer; and

a step of forming a third insulating resin layer covering at least one of the surfaces of the first and second insulating resin layers, and

the top surfaces of the respective turns of the second planar spiral conductor and top surfaces of the respective turns of the third planar spiral conductor are electrically isolated from each other by the third insulating resin layer.

22. The manufacturing method of a coil component according to claim 19, wherein

the insulating resin layer formation step may further include a step of forming the first insulating resin layer so as to cover also the first planar spiral conductor, forming the second insulating resin layer so as to cover the fourth planar spiral conductor,

the method further comprises:

a step of forming a metal-magnetic-powder-containing resin layer covering the surfaces the first and fourth planar spiral conductors on which the first and second insulating resin layers are formed; and

a step of forming an insulating layer on a surface of the metal-magnetic-powder-containing resin layer, and

the external electrode formation step forms the first and second external electrodes after the formation of the insulating layer.