EP0133010A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Multilayered ceramic circuit board
Assignee: Hitachi Ltd
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Filing: 1984-07-24
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Granted: —
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Expires: 2004-07-24
Abstract
Abstract @ A multilayered ceramic circuit board in which conductive material 4 and ceramic material 5 are alternatingly laminated, and wiring between the conductive layers 4 is connected by conductive material 3 in through holes in the ceramic layers. So that the circuit board is less sensitive to cracks due to thermal stress, the conductive material has a coefficient of thermal expansion which is greater than the coefficient of thermal expansion of said ceramic material, the respective materials are selected so that the difference between the coefficients of thermal expansion of the conductive material and the ceramic material is less than 100 x 10 7 /°C. In particular, the conductive material comprises a metal and a glass composition which contains a SiO 2 - containing filler. The glass composition contains Si02 in an amount of 5 to 90% by weight, B 2 O 3 in an amount of 10 to 70% by weight and a refractory additive in an amount of 1 to 55% by weight.
Inventors
- 👤 Nobuyuki Ushifusa
- 👤 Satoru Ogihara
- 👤 Takanobu Noro
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 07:09
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/60; H10W70/611; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H10W70/62; H10W70/63; H10W70/635; H10W70/66; H10W70/666; H10W70/67; H10W70/69; H10W90/00; H10W90/701; H10W90/721; H10W90/724
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
165 words
A multilayered ceramic circuit board which comprises a plurality of ceramic layers (5) each having an electrically conductive layer (4) thereon, each ceramic layer being integrally bonded to the adjacent ceramic layer(s) and there being wiring means (3) electrically connecting the said conductive layers (4) via through-holes formed in the ceramic layers to form a desired circuit, wherein the conductive layers consist essentially of electro-conductive metal and a glass composition having a softening point in the range 600°C to 850°C and the ceramic layers each have a softening point in the range 600°C to 850°C and a dielectric constant of less than 5.7, the said glass composition comprising a glass component consisting essentially of Si0 2 in an amount of 5 to 90% by weight, B 2 O 3 in an amount of 10 to 70% by weight and a refractory additive in an amount of 1 to 55% by weight and further containing a filler in the form of an SiO 2 -containing additive.
Claim 2
Dependent Claim
165 words
A multilayered ceramic circuit board which comprises a plurality of ceramic layers (5) each having an electrically conductive layer (4) thereon, each ceramic layer being integrally bonded to the adjacent ceramic layer(s) and there being wiring means (3) electrically connecting the said conductive layers (4) via through-holes formed in the ceramic layers to form a desired circuit, wherein the conductive layers consist essentially of electro-conductive metal and a glass composition having a softening point in the range 600°C to 850°C and the ceramic layers each have a softening point in the range 600°C to 850°C and a dielectric constant of less than 5.7, the said glass composition comprising a glass component consisting essentially of Si0 2 in an amount of 5 to 90% by weight, B 2 O 3 in an amount of 10 to 70% by weight and a refractory additive in an amount of 1 to 55% by weight and further containing a filler in the form of an SiO 2 -containing additive.
Claim 3
Dependent Claim
95 words
A circuit board according to claim 1, wherein said glass component consists essentially of, by weight, SiO 2 in an amount of 10 to 80%, B 2 0 3 in an amount of 15 to 65%, A1 2 0 3 in an amount of 3 to 27%, up to 15% of MgO, up to 35% of BaO, up to 45% of AlPO 4 , up to 18% of MgF 2 , up to 10% of K 2 0, up to 5% of Na 2 O, and up to 17% of Bi 2 0 3 .
Claim 4
Dependent Claim
103 words
A circuit board according to claim 2, wherein the said glass component consists essentially of, by weight, SiO 2 in an amount of 30 to 50%, B 2 O 3 in an amount of 20 to 50%, A1 2 0 3 in an amount of 5 to 15%, up to 10% of MgO, up to 20% of BaO, up to 30% of AlPO 4 , up to 10% of MgF 2 , up to 10% of K 2 0, up to 5% of Na 2 0, and up to 10% of Bi203, and the glass composition has a softening point lower than 850°C.
Claim 5
Dependent Claim
38 words
A circuit board according to claim 1 or claim 2, wherein the said Sio 2 -containing additive has a linear thermal expansion coefficient of less than 100 x 10 -7 /°C over the temperature of 25 to 850°C.
Claim 6
Dependent Claim
35 words
A circuit board according to any one of claims 1 to 4, wherein the SiO 2 -containing additive is a member selected from the group consisting of quartz, quartz glass, cristoballite, tridymite and mixtures thereof.
Claim 7
Dependent Claim
56 words
A circuit board according to claim 1, wherein the glass composition consists essentially of 30 to 60 % of SiO 2 , 10 to 40% of B203, 5 to 15% of Al 2 O 3 , 2 to 15% of BaO and/or MgO, and up to 5% of Na 2 0 and/ or K 2 0.
Claim 8
Dependent Claim
66 words
A circuit board according to any one of the preceding claims, wherein said conductive layers have a coefficient of thermal expansion larger than that of said ceramic material, wherein the materials for the conductive layers and ceramic material are selected so that the difference between the coefficients of thermal expansion of the conductive layers and the ceramic material is less than 100 x 10 -7 /°C.
Claim 9
Dependent Claim
31 words
A circuit board according to any one of the preceding claims wherein said metal is a member selected from the group consisting of silver, copper, gold, their alloys and mixtures thereof.
Claim 10
Dependent Claim
31 words
A circuit board according to any one of the preceding claims wherein said ceramic layers have a coefficient of thermal expansion in the range 30 to 70 x 10 -7 /°C.
Claim 11
Dependent Claim
28 words
A multilayered ceramic circuit board according to claim 1, wherein said glass composition in said conductive layers is the same glass composition as that for said ceramic layers.
Claim 12
Dependent Claim
28 words
A circuit board according to any one of the preceding claims wherein said conductive layers have a coefficient of thermal expansion larger than that of said ceramic layers.
References Cited (Backward Citations)
No citation records indexed.
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