INDUCTOR AND ELECTRIC POWER SUPPLY USING IT

• US 20100117779A1
• Filed: 01/25/2010
• Published: 05/13/2010
• Est. Priority Date: 05/08/2006
• Status: Active Grant

• Current Assignee: Ibiden Co., Ltd.
• Original Assignee: Ibiden Co., Ltd.
• Inventors: Kato, Shinobu, Kariya, Takashi, MANO, Yasuhiko
• Granted Patent: US 7,868,728 B2
• 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 17/06 with core substantially closed in itself, e.g. toroid
• CPC Class Codes: H01F 2017/002 Details of via holes for interconnecting the layers
• CPC Class Codes: H01F 2017/065 Core mounted around conductor to absorb noise, e.g. EMI filter
• CPC Class Codes: H01F 41/046 structurally combined with ferromagnetic material
• CPC Class Codes: H01L 2224/05568 the whole external layer protruding from the surface
• CPC Class Codes: H01L 2224/05573 Single external layer
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16235 the bump connector connecting to a via metallisation of the item
• CPC Class Codes: H01L 23/645 Inductive arrangements H01L23/647, H01L23/66 take precedence
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01087 Francium [Fr]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/15312 being a pin array, e.g. PGA
• CPC Class Codes: H01L 2924/1532 the connection portion being formed on the die mounting surface of the substrate
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding
• CPC Class Codes: H05K 1/0233 : Filters, inductors or a magnetic substance
• CPC Class Codes: H05K 1/115 : Via connections; Lands around holes or via connections H05K1/112 takes precedence
• CPC Class Codes: H05K 1/185 : Components encapsulated in the insulating substrate of the printed circuit or incorporated in internal layers of a multilayer circuit semiconductor chips encapsulated by interconnect and support structures H01L23/5389, H01L24/00
• CPC Class Codes: H05K 2201/086 : for inductive purposes, e.g. printed inductor with ferrite core
• CPC Class Codes: H05K 2201/09581 : Applying an insulating coating on the walls of holes
• CPC Class Codes: H05K 3/4046 : using auxiliary conductive elements, e.g. metallic spheres, eyelets, pieces of wire
• CPC Class Codes: H05K 3/42 : Plated through-holes or plated via connections
• CPC Class Codes: H05K 3/4602 : characterized by a special circuit board as base or central core whereon additional circuit layers are built or additional circuit boards are laminated
• CPC Class Codes: Y10T 29/4902 : Electromagnet, transformer or inductor

Abstract

An inductor embedded in a printed wiring board includes a conductor extending in the thickness direction of a printed circuit board and a magnetic body that is in contact with the conductor with no gap therebetween. For example, the magnetic body is composed of ferrite having a cylindrical tubular shape. The conductor is composed of a copper film formed by plating on an inner peripheral surface of the cylindrical tubular ferrite. The inductor is inserted in the thickness direction of the printed wiring board.

Claims

1. A printed wiring board comprising:

a core substrate;

conductive circuits formed on top and bottom surfaces of the core substrate, respectively;

a through-hole conductor formed in the core substrate and electrically connecting the conductive circuits;

an inductor formed in the core substrate; and

a build-up layer formed on the core substrate and consisting of alternately laminated insulating layers and conductive circuits, the conductive circuits provided on different layers electrically connected each other through a via hole conductor;

wherein said inductor includes a magnetic body that extends in the thickness direction of the core substrate and that has a through-hole and a conductor provided on an inner surface of the through-hole.

2. The printed wiring according to claim 1, further comprising:

a via conductor provided on the inductor.

3. The printed wiring board according to claim 1, wherein the conductor is composed of copper.

4. The printed wiring board according to claim 1, wherein the conductor is composed of copper and has a substantially cylindrical shape.

5. The printed wiring board according to claim 1, wherein the conductor is composed of copper and has a substantially hollow cylindrical shape.

6. The printed wiring board according to claim 1, wherein the magnetic body surrounds the side face of the conductor.

7. The printed wiring board according to claim 1, wherein the magnetic body is composed of ferrite.

8. The printed wiring board according to claim 1, wherein the magnetic body is composed of a composite material containing a magnetic material and a nonmagnetic material.

9. The printed wiring board according to claim 1, wherein the magnetic body is composed of a composite material containing a magnetic powder and a resin.

10. The printed wiring board according to claim 1, wherein the magnetic body is composed of a composite material containing a carbonyl iron powder and a resin.

11. The printed wiring board according to claim 1, further comprising:

a dielectric material,

wherein the dielectric material surrounds the side face of the magnetic body.

12. The printed wiring board according to claim 1, further comprising:

a dielectric material,

wherein the dielectric material is composed of an under-fill material having low thermal expansion characteristics.