Boron nitride/resin composite circuit board, and circuit board including boron nitride/resin composite integrated with heat radiation plate

Patent metadata

Field	Value
Publication number	US-9516741-B2
Application number	US-201414911707-A
Country	US
Kind code	B2
Filing date	Aug 12, 2014
Priority date	Aug 14, 2013
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A boron nitride/resin composite circuit board having high heat dissipation characteristics and high reliability is provided. A boron nitride/resin composite circuit board, including: a plate-shaped resin-impregnated boron nitride sintered body having a plate thickness of 0.2 to 1.5 mm, the plate-shaped resin-impregnated boron nitride sintered body including 30 to 85 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally, the boron nitride particles having an average long diameter of 5 to 50 μm, and 70 to 15 volume % of a resin; and a metal circuit adhered onto both principal planes of the plate-shaped resin-impregnated boron nitride sintered body, the metal circuit being copper or aluminum, wherein: a ratio of a linear thermal expansion coefficient in a plane direction of the resin-impregnated boron nitride sintered body at 40 to 150° C. (CTE1) and a linear thermal expansion coefficient of the metal circuit at 40 to 150° C. (CTE2) (CTE1/CTE2) is 0.5 to 2.0.

First claim

The invention claimed is:

1. A boron nitride/resin composite circuit board, comprising:
a plate-shaped resin-impregnated boron nitride sintered body having a plate thickness of 0.2 to 1.5 mm, the plate-shaped resin-impregnated boron nitride sintered body comprising 30 to 85 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally, the boron nitride particles having an average long diameter of 5 to 50 μm, and 70 to 15 volume % of a resin; and
a metal circuit adhered onto both principal planes of the plate-shaped resin-impregnated boron nitride sintered body, the metal circuit being copper, aluminum, or alloys thereof; wherein:
a ratio of a linear thermal expansion coefficient in a plane direction of the resin-impregnated boron nitride sintered body at 40 to 150° C. (CTE1) and a linear thermal expansion coefficient of the metal circuit at 40 to 150° C. (CTE2) (CTE1/CTE2) is 0.5 to 2.0.

2. The boron nitride/resin composite circuit board of claim 1 , wherein a graphitization index (GI) of the resin-impregnated boron nitride sintered body by powder X-ray diffractometry is 4.0 or lower.

3. The boron nitride/resin composite circuit board of claim 1 , wherein a strength of the boron nitride/resin composite circuit board is 10 to 70 MPa, and a thermal conductivity in a plate thickness direction is 10 to 110 W/(m·K).

4. The boron nitride/resin composite circuit board of claim 1 , wherein the resin is a thermosetting resin.

5. The boron nitride/resin composite circuit board of claim 1 , wherein a plate thickness of the metal circuit is 0.05 to 1.5 mm.

6. The boron nitride/resin composite circuit board of claim 1 , wherein an adhesion layer provided between the resin-impregnated boron nitride sintered body and the metal circuit is an epoxy-resin composition comprising an epoxy resin and an inorganic filler.

7. The boron nitride/resin composite circuit board according to claim 1 , wherein with respect to the metal circuit provided on at least one principal plane of the plate-shaped resin-impregnated boron nitride sintered body, a ratio of a projected area A/a projected area B is 1 or larger, the projected areas A and B being projected areas observed from a direction perpendicular to a principal plane of the plate-shaped resin-impregnated boron nitride sintered body, the projected area A being a projected area of a profile of the metal circuit, the projected area B being a projected area of a profile of the plate-shaped resin-impregnated boron nitride sintered body.

8. A power module comprising the boron nitride/resin composite circuit board of claim 1 .

9. A circuit board including boron nitride/resin composite integrated with heat dissipation plate, comprising:
a resin-impregnated boron nitride sintered body comprising 30 to 85 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally, the boron nitride particles having an average long diameter of 5 to 50 μm, and 70 to 15 volume % of a resin;
a metal circuit having a thickness of 0.03 to 3.0 mm formed onto one principal plane of the resin-impregnated boron nitride sintered body with an intermediary of an adhesion layer; and
a metal heat dissipation plate having a thickness of 2.0 to 7.0 mm formed onto a rear surface of the resin-impregnated boron nitride sintered body with an intermediary of an adhesion layer.

10. The circuit board including boron nitride/resin composite integrated with heat dissipation plate of claim 9 , wherein the metal circuit and the metal heat dissipation plate comprises copper, aluminum, or an alloy thereof.

11. The circuit board including boron nitride/resin composite integrated with heat dissipation plate of claim 9 , wherein the metal circuit and the metal heat dissipation plate is a different metal.

12. The circuit board including boron nitride/resin composite integrated with heat dissipation plate of claim 9 , wherein a thermal conductivity of the resin-impregnated boron nitride sintered body in a plate thickness direction is 20 W/mK or more, and a thermal coefficient of linear expansion in a plane direction in a temperature range of 25 to 200° C. is 12 to 30 ppm/K.

13. A power module comprising the circuit board including boron nitride/resin composite integrated with heat dissipation plate of claim 9 .

Assignees

• Denka Company Ltd

Inventors

• Hirotsuru Hideki
• Nonaka Shuhei
• Mitsunaga Toshikatsu
• Ikarashi Koki
• Miyata Kouji
• Nishi Taiki
• Inoue Saori
• Kobayashi Fumiya

Classifications

• H05K1/0306

  Inorganic insulating substrates, e.g. ceramic, glass · CPC title

• H05K3/38

  Improvement of the adhesion between the insulating substrate and the metal · CPC title

• H05K2201/0104

  Properties and characteristics in general · CPC title

• H05K2201/066

  Heatsink mounted on the surface of the printed circuit board [PCB] · CPC title

• H05K1/0353 Primary

  consisting of two or more materials, e.g. two or more polymers, polymer + filler, + reinforcement · CPC title