INDUCTOR COMPONENT AND PRINTED WIRING BOARD INCORPORATING INDUCTOR COMPONENT AND METHOD FOR MANUFACTURING INDUCTOR COMPONENT

• US 20120212919A1
• Filed: 01/27/2012
• Published: 08/23/2012
• Est. Priority Date: 02/18/2011
• Status: Active Grant

• Current Assignee: Ibiden Co., Ltd.
• Original Assignee: Ibiden Co., Ltd.
• Inventors: Kato, Shinobu, Kariya, Takashi, MANO, Yasuhiko
• Granted Patent: US 9,265,158 B2
• Time in Patent Office: Days
• US Class Current: 361/782
• CPC Class Codes: H01F 17/0033 with the coil helically wound around a magnetic core
• CPC Class Codes: H01F 2017/004 with the coil helically wound around an axis without a core
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01L 2924/15311 being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/3511 Warping
• 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 2201/1003 Non-printed inductor
• CPC Class Codes: H05K 2203/1469 Circuit made after mounting or encapsulation of the components
• CPC Class Codes: H05K 2203/1572 Processing both sides of a PCB by the same process; Providing a similar arrangement of components on both sides; Making interlayer connections from two sides
• CPC Class Codes: H05K 3/0032 of organic insulating material
• 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 29/4913 Assembling to base an electrical component, e.g., capacitor, etc.

Abstract

A printed wiring board includes a core substrate having a cavity and having first and second surfaces, an inductor component accommodated in the cavity, a filler resin filling a gap formed between the substrate and component in the cavity, and a buildup layer formed on the first surface of the substrate and the component. The component has a coil layer, a second insulation layer formed on the coil layer, an electrode formed on the substance layer, and a via conductor formed in the substance layer and connecting the coil layer and the electrode, the component is accommodated in the cavity such that the electrode faces the first surface of the substrate, and the buildup layer includes an interlayer insulation layer formed on the first surface of the substrate and the component, a conductive layer formed on the insulation layer, and a connection via conductor connecting the conductive layer and electrode.

Claims

1. A wiring board, comprising:

a substrate having a cavity portion;

a buildup layer formed on the substrate and comprising a plurality of conductive layers and a plurality of insulation layers; and

an inductor component accommodated in the cavity portion of the substrate and comprising a plurality of second insulation layers and a plurality of second conductive patterns,

wherein the substrate, the buildup layer and the inductor component satisfy that a ratio of P1/S1 is set greater than a ratio of P2/S2, where Si represents a cross-sectional area of the inductor component, P1 represents a sum of cross-sectional areas of the second conductive patterns, S2 represents a sum of cross sectional areas of the substrate and the buildup layer, P2 represents a sum of cross-sectional areas of the conductive layers, and the cross sectional areas is areas of cross sections taken in a thickness direction of the substrate, the buildup layer and the inductor component.

2. The wiring board according to claim 1, wherein a ratio of P1/S1 to P2/S2 is set 2 or greater and 3 or less.

3. The wiring board according to claim 1 or 2, wherein the ratio of P1/S1 is set 0.6 or greater and 0.9 or less.

4. The wiring board according to claim 1, wherein each of the second conductive patterns has a thickness which is set greater than a thickness of each of the conductive layers.

5. The wiring board according to claim 1, wherein the second conductive patterns of the inductor component are electrically connected to the conductive layers of the buildup layer through a plurality of via conductors.

6. The wiring board according to claim 1, wherein the plurality of second conductive patterns of the inductor component forms a plurality of inductors connected parallel to each other.

7. The wiring board according to claim 1, further comprising a chip capacitor accommodated in the substrate.

8. The wiring board according to claim 7, wherein the chip capacitor is electrically connected to the inductor component.

9. A method for manufacturing the wiring board, comprising:

preparing an inductor component having a plurality of second insulation layers and a plurality of second conductive patterns;

accommodating the inductor component into a cavity portion of a substrate; and

forming on the substrate a buildup layer comprising a plurality of conductive layers and a plurality of insulation layers,

wherein the substrate, the buildup layer and the inductor component satisfy that a ratio of P1/S1 is set greater than a ratio of P2/S2, where Si represents a cross-sectional area of the inductor component, P1 represents a sum of cross-sectional areas of the second conductive patterns, S2 represents a sum of cross sectional areas of the substrate and the buildup layer, P2 represents a sum of cross-sectional areas of the conductive layers, and the cross sectional areas is areas of cross sections taken in a thickness direction of the substrate, the buildup layer and the inductor component.

10. A printed wiring board, comprising:

a core substrate having a cavity portion and having a first surface and a second surface on an opposite side of the first surface;

an inductor component accommodated in the cavity portion of the core substrate;

a filler resin filling a gap formed between the core substrate and the inductor component in the cavity portion of the core substrate; and

a first buildup layer formed on the first surface of the core substrate and on the inductor component,

wherein the inductor component comprises at least one coil layer forming a wiring pattern on a plane, at least one second insulation layer formed on the coil layer, an electrode formed on the second insulation layer, and a via conductor formed in the second insulation layer and connecting the coil layer and the electrode, the inductor component is accommodated in the cavity portion of the core substrate such that the electrode faces the first surface of the core substrate, and the first buildup layer includes a first interlayer resin insulation layer formed on the first surface of the core substrate and on the inductor component, a conductive layer formed on the first interlayer resin insulation layer, and a connection via conductor connecting the conductive layer and the electrode in the inductor component.

11. The printed wiring board according to claim 10, wherein the inductor component comprises a plurality of the coil layers and a plurality of the second insulation layers, the plurality of second insulation layers includes an uppermost second insulation layer, the coil layers and the second insulation layers are alternately laminated, the inductor component comprises a plurality of via conductors formed in the second insulation layers and connecting the coil layers through the second insulation layers, and the electrode is formed on the uppermost second insulation layer.

12. The printed wiring board according to claim 11, wherein the plurality of second insulation layers includes a lowermost second insulation, the plurality of coil layers include a lowermost coil layer, and the lowermost coil layer is formed on the lowermost second insulation layer.

13. The printed wiring board according to claim 10, wherein each of the second insulation layers comprises an insulating resin and magnetic-substance particles dispersed in the insulating resin.

14. The printed wiring board according to claim 10, wherein the inductor component is covered with one of a magnetic-substance film and a coating layer comprising magnetic-substance particles.

15. The printed wiring board according to claim 11, further comprising an uppermost coil layer forming a wiring pattern on the uppermost second insulation layer, wherein the electrode is formed on an end portion of the uppermost coil layer.

16. The printed wiring board according to claim 11, further comprising an uppermost coil layer forming a wiring pattern on the uppermost second insulation layer, wherein the electrode is formed on the uppermost coil layer.

17. A method for manufacturing an inductor component, comprising:

forming a lowermost insulation layer on a support sheet;

forming a coil layer having a wiring pattern on the lowermost insulation layer;

forming a second insulation layer on the coil layer and the lowermost insulation layer;

forming in the second insulation layer a via-conductor opening reaching to the coil layer;

forming an electrode on the second insulation layer;

forming a via conductor in the via-conductor opening such that the electrode is connected to the coil layer; and

separating the support body from the lowermost insulation layer.

18. The method for manufacturing an inductor component according to claim 17, wherein the forming of the electrode comprises forming a second coil layer forming a wiring pattern on the second insulation layer, and the electrode is formed at an end portion of the second coil layer.

19. The method for manufacturing an inductor component according to claim 17, wherein the second insulation layer comprises an insulating resin and magnetic-substance particles dispersed in the insulating resin.

20. An inductor component for being incorporated into a printed wiring board, manufactured by the method for manufacturing an inductor component according to claim 17.