PRINTED WIRING BOARD AND METHOD FOR MANUFACTURING PRINTED WIRING BOARD

• US 20140020940A1
• Filed: 07/10/2013
• Published: 01/23/2014
• Est. Priority Date: 07/18/2012
• Status: Active Grant

• Current Assignee: Ibiden Co., Ltd.
• Original Assignee: Ibiden Co., Ltd.
• Inventors: MANO, Yasuhiko, YOSHIKAWA, Kazuhiro, KARIYA, Takashi
• Granted Patent: US 9,307,645 B2
• Time in Patent Office: Days
• US Class Current: 174/258
• CPC Class Codes: H01L 2924/3511 Warping
• CPC Class Codes: H05K 1/0233 Filters, inductors or a magnetic substance
• CPC Class Codes: H05K 1/165 incorporating printed inductors
• CPC Class Codes: H05K 1/186 manufactured by mounting on or connecting to patterned circuits before or during embedding
• CPC Class Codes: H05K 2201/0209 Inorganic, non-metallic particles
• CPC Class Codes: H05K 3/0032 of organic insulating material
• CPC Class Codes: H05K 3/30 Assembling printed circuits with electric components, e.g. with resistor
• CPC Class Codes: H05K 3/4676 Single layer compositions
• CPC Class Codes: H05K 3/4697 having cavities, e.g. for mounting components H05K3/4691 takes precedence
• 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, a first buildup layer formed on a first surface of the core substrate and including an insulation layer and a conductive layer, a second buildup layer formed on a second surface of the core substrate on the opposite side with respect to the first buildup layer and including an insulation layer and a conductive layer, and an inductor device positioned in the second buildup layer and including a resin insulation layer and a coil layer formed on the resin insulation layer. The second buildup layer has a cavity in which the inductor device is accommodated.

Claims

1. A printed wiring board, comprising:

a core substrate;

a first buildup layer formed on a first surface of the core substrate and comprising an insulation layer and a conductive layer;

a second buildup layer formed on a second surface of the core substrate on an opposite side with respect to the first buildup layer and comprising an insulation layer and a conductive layer; and

an inductor device positioned in the second buildup layer and comprising a resin insulation layer and a coil layer formed on the resin insulation layer,

wherein the second buildup layer has a cavity in which the inductor device is accommodated.

2. The printed wiring board according to claim 1, wherein the inductor device has the resin insulation layer in a plurality, the coil layer in a plurality and a plurality of via conductors formed in the plurality of resin insulation layers such that the via conductors are formed in the resin insulation layers and connecting the coil layers through the resin insulation layers.

3. The printed wiring board according to claim 2, wherein the core substrate has a through-hole conductor formed through the core substrate, the cavity of the second buildup layer is formed such that the cavity is exposing a portion of the second surface of the core substrate and an end portion of the through-hole conductor on the portion of the second surface of the core substrate, and the inductor device has an electrode connected to the end portion of the through-hole conductor.

4. The printed wiring board according to claim 2, wherein the resin insulation layer of the inductor device has a thickness which is less than a thickness of the insulation layer of the second buildup layer.

5. The printed wiring board according to claim 2, wherein the insulation layer in the second buildup layer is formed in a plurality, and the inductor device has the plurality of resin insulation layers in a number greater than a number of the plurality of insulation layers in the second buildup layer.

6. The printed wiring board according to claim 2, further comprising a filler resin material filling a gap formed around the inductor device in the cavity of the second buildup layer.

7. The printed wiring board according to claim 6, wherein the filler resin material includes magnetic particles.

8. The printed wiring board according to claim 6, wherein the filler resin material is filling a space formed between the second surface of the core substrate and the inductor device.

9. The printed wiring board according to claim 1, further comprising a cover insulation layer formed on the second buildup layer such that the cover insulation layer is covering the inductor device and the second buildup layer, wherein the cover insulation layer has a portion directly on the inductor device, and the portion of the cover insulation layer directly on the inductor device has no conductive circuit formed thereon.

10. The printed wiring board according to claim 1, further comprising a solder-resist layer formed on the second buildup layer such that the solder-resist layer is covering the inductor device.

11. The printed wiring board according to claim 3, further comprising a conductive member connecting the electrode of the inductor device and the end portion of the through-hole conductor.

12. The printed wiring board according to claim 1, further comprising a chip capacitor mounted on the second buildup layer.

13. A method for manufacturing a printed wiring board, comprising:

forming on a first surface of a core substrate a first buildup layer comprising an insulation layer and a conductive layer;

forming on a second surface of the core substrate on an opposite side with respect to the first buildup layer a second buildup layer comprising an insulation layer and a conductive layer;

forming in the second buildup layer a cavity for accommodating an inductor device comprising a resin insulation layer and a coil layer formed on the resin insulation layer; and

accommodating the inductor device in the cavity of the second buildup layer such that the inductor device is positioned in the cavity of the second buildup layer.

14. The method for manufacturing a printed wiring board according to claim 13, further comprising:

filling a filler resin material into a gap formed around the inductor device in the cavity of the second buildup layer.

15. The method for manufacturing a printed wiring board according to claim 14, wherein the filler resin material includes magnetic particles.

16. The method for manufacturing a printed wiring board according to claim 13, further comprising:

forming a cover insulation layer on the second buildup layer such that the cover insulation layer is covering the inductor device and the second buildup layer; and

forming a conductive circuit on the cover insulation layer such that the conductive circuit is not formed on a portion of the cover insulation layer directly on the inductor device.

17. The method for manufacturing a printed wiring board according to claim 13, further comprising:

forming a solder-resist layer on the second buildup layer such that solder-resist layer is covering the inductor device.

18. The method for manufacturing a printed wiring board according to claim 13, wherein the forming of the cavity comprises forming a cavity in the second buildup layer such that the cavity exposes a portion of the second surface of the core substrate.

19. The method for manufacturing a printed wiring board according to claim 13, wherein the core substrate has a through-hole conductor formed through the core substrate, the forming of the cavity comprises forming a cavity in the second buildup layer such that the cavity exposes an end portion of the through-hole conductor and a portion of the second surface of the core substrate, and the accommodating of the inductor device includes connecting the end portion of the through-hole conductor and an electrode of the inductor device.

20. The method for manufacturing a printed wiring board according to claim 13, further comprising:

mounting a chip capacitor on the second buildup layer.