Electric element incorporating wiring board

• US 6,370,013 B1
• Filed: 11/21/2000
• Issued: 04/09/2002
• Est. Priority Date: 11/30/1999
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Iino, Yuji, Hayashi, Katsura, Iwachi, Hiromi
• Primary Examiner(s): Dinkins, Anthony
• Application Number:
  US09/717,541
• Time in Patent Office: 504 Days
• Field of Search: 361/306.3, 361/307, 361/308.3, 361/309, 361/313, 361/321.2, 361/329, 361/330, 361/306.1, 361/763, 361/811, 361/807, 361/809
• US Class Current: 361/306.3
• CPC Class Codes: H01G 4/2325 characterised by the material of the terminals
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/16235 the bump connector connecting to a via metallisation of the item
• CPC Class Codes: H01L 2224/82047 by mechanical means, e.g. severing, pressing, stamping
• CPC Class Codes: H01L 23/49822 Multilayer substrates multilayer metallisation on monolayer substrate H01L23/498
• CPC Class Codes: H01L 23/642 Capacitive arrangements H01L23/49589, H01L23/645, H01L23/647, H01L23/66 take precedence; capacitive effects between wiring layers on the semiconductor body H01L23/5222
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/01057 Lanthanum [La]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01327 Intermediate phases, i.e. intermetallics compounds
• CPC Class Codes: H01L 2924/10253 Silicon [Si]
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H05K 1/0231 Capacitors or dielectric substances
• CPC Class Codes: H05K 1/186 manufactured by mounting on or connecting to patterned circuits before or during embedding
• 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: H05K 3/4617 characterized by laminating only or mainly similar single-sided circuit boards

Abstract

A wiring board that incorporates electric element such as capacitor. The wiring board includes a dielectric substrate having electronic components mounting surface on the surface thereof, an electric element that is embedded in the dielectric substrate, a first conductive layer and a second conductive layer formed inside of the dielectric substrate, and via hole conductors that connect the first terminal electrode and the second terminal electrode of the electric element to the first conductive layer and the second conductive layer, respectively, and extend the surface of the dielectric substrate from the first and second conductive layers. In case both the first and the second terminal electrodes are provided in plurality, all of the plurality of first terminal electrodes are connected to the first conductive layer through the via hole conductors and all of the plurality of second terminal electrodes are connected to the second conductive layer through the via hole conductors.

Claims

1. An electric element incorporating wiring board comprising:

a dielectric substrate having an electronic component mounting surface on a surface thereof;

an electric element that has a first terminal electrode and a second terminal electrode and is incorporated in the dielectric substrate;

a first conductive layer and a second conductive layer formed while being insulated from each other between the surface of the dielectric substrate and the electric element in the dielectric substrate; and

via hole conductors that connect the first terminal electrode and the second terminal electrode to the first conductive layer and the second conductive layer, respectively, and extend the surface of the dielectric substrate from the first and second conductive layers.

2. An electric element incorporating wiring board according to claim 1, wherein the electric element is a capacitor.

3. An electric element incorporating wiring board according to claim 2, wherein the capacitor is a laminated ceramic capacitor.

4. An electric element incorporating wiring board according to claim 1, wherein the electric element has a plurality of first terminal electrodes and second terminal electrodes, while all of the first terminal electrodes are connected to the first conductive layer through the via hole conductors and all of the second terminal electrodes are connected to the second conductive layer through the via hole conductors.

5. An electric element incorporating wiring board according to claim 1, wherein thickness of an insulation layer disposed between the electric element and the surface of the dielectric substrate is 0.3 mm or less.

6. An electric element incorporating wiring board according to claim 1, wherein the dielectric substrate contains at least an organic resin.

7. An electric element incorporating wiring board according to claim 1, wherein the dielectric substrate has a laminated structure including a first insulation layer made up of a mixture of a thermosetting resin and an inorganic filler and a second insulation layer made by impregnating a fabric with a thermosetting resin.

8. An electric element incorporating wiring board according to claim 7, wherein the electric element is embedded in the first insulation layer and the difference in the thermal expansion coefficient between the electric element and the first insulation layer is 7×

10<sup>−

6</sup>/°

C. or less.

9. An electric element incorporating wiring board according to claim 7, wherein the electric element is embedded in the first insulation layer and the second insulation layer is disposed on an outermost layer of the dielectric substrate.

10. An electric element incorporating wiring board according to claim 7, wherein the first insulation layer includes 30 to 65% by volume of thermosetting resin and 35 to 70% by volume of inorganic filler.

11. An electric element incorporating wiring board according to claim 7, wherein the inorganic filler includes at least one kind of material selected from SiO₂Al₂O₃, AlN and Si₃N₄.

12. An electric element incorporating wiring board according to claim 7, wherein the thermosetting resin included in the first insulation layer and second insulation layer includes at least one kind of material selected from polyphenylene ether resin, epoxy resin and cyanate resin.

13. An electric element incorporating wiring board according to claim 1, wherein the via hole conductors are formed by filling via holes made in the dielectric substrate with a metal component.

14. An electric element incorporating wiring board according to claim 1, wherein the first and the second terminal electrodes of the electric element and the via hole conductors are directly connected to each other, while intermetallic compound of Cu and Sn exists in junctions between the first and second terminal electrodes and the respective via hole conductors.

15. An electric element incorporating wiring board according to claim 14, wherein the via hole conductors include Cu and Sn as metal components.

16. An electric element incorporating wiring board according to claim 15, wherein weight ratio Sn/(Cu+Sn) in the metal component is in a range from 0.5 to 0.95.

17. An electric element incorporating wiring board according to claim 14, wherein a conductive layer that includes at least Sn is formed on an outermost surface of the first and the second terminal electrodes of the electric element.

18. An electric element incorporating wiring board according to claim 1, wherein one of adjacent pair of via hole conductors is connected to the first conductive layer and another is connected to the second conductive layer.

19. An electric element incorporating wiring board according to claim 1, wherein a plurality of electric elements each having a first terminal electrode and a second terminal electrode are embedded in the dielectric substrate.

20. An electric element incorporating wiring board according to claim 19, wherein a pair of via hole conductors that are most proximate to each other between adjacent electric elements are connected to different ones of the first and second conductive layers, current flowing through the pair of via hole conductors in directions opposite to each other.

21. An electric element incorporating wiring board according to claim 20, wherein distance between a pair of via hole conductors that are most proximate to each other between the adjacent electric elements is 0.5 mm or less.

22. An electric element incorporating wiring board according to claim 19, wherein the plurality of electric elements include capacitors having different values of capacitance.

23. An electric element incorporating wiring board according to claim 1, wherein the first and second terminal electrodes are made by forming a conductive material on a principal surface of a body of the electric element.

24. An electric element incorporating wiring board according to claim 1, wherein surfaces of the electric element other than the first and second terminal electrodes are covered by a thermoplastic resin having a glass transition point not higher than 100°

C.

25. An electric element incorporating wiring board according to claim 24, wherein thickness of the coating layer of the thermoplastic resin is in a range from 5 to 150 μ

m.

26. An electric element incorporating wiring board according to claim 24, wherein the dielectric substrate includes an insulation layer that contains a PPE (polyphenylene ether) resin.

27. An electric element incorporating wiring board according to claim 24, wherein the thermoplastic resin consists of at least one selected from the groups of polyester resin, polyamide resin and polyurethane resin.