EP0265340A2
Expired / Lapsed
EP
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Multilayer ceramic copper circuit board
Assignee: Fujitsu Ltd
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Filing: 1987-10-20
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Granted: —
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Expires: 2007-10-20
Abstract
Abstract A multilayer ceramic copper circuit board was produced by forming a multilayer structure comprising layers of copper-based paste patterns and layers of glass-ceramic. The glass-ceramic consisted of a mixture of 3% to 75% by weight of mullite, 25% to 97% by weight of borosilicate glass having a softening temperature of at least 720°C, and 0% to 70% by weight of quartz glass, based on the total weight of the glass-ceramic, and blended with a binder composition containing a thermally depolymerizable resin. The multilayer structure was prefired in an inert atmosphere containing water vapor and having a partial pressure of 0.005 to 0.3 atmosphere, at a temperature at which the thermally depolymerizable resin was eliminated, the multilayer structure was then fired in an inert atmosphere containing no water vapor at a temperature below the melting temperature of copper, to sinter the glass-ceramic.
Inventors
- 👤 Shigenori Aoki
- 👤 Yoshihiko Imanaka
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 04:31
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/46; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H05K3/4611; H05K3/4626; H05K3/4629; H05K3/4644; H05K3/4673; H05K3/4676; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24917; Y10T428/31504; Y10T428/31678
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
143 words
A method for producing a multilayer ceramic copper circuit board comprising the steps of: forming a multilayer structure comprising layers of copper-based paste patterns and layers of glass-ceramic, the glass-ceramic consisting of a mixture of 3% to 75% by weight of mullite, 25% to 97% by weight of borosilicate glass having a softening temperature of at least 720°C, and 0% to 70% by weight of quartz glass, based on a total weight of the glass-ceramic, blended with a binder composition containing a thermally depolymerizable resin; prefiring the multilayer structure in an inert atmosphere containing water vapor, and having a partial pressure of 0.005 to 0.3 atmosphere, at a temperature at which the thermally depolymerizable resin is eliminated; and firing the multilayer structure in an inert atmosphere containing no water vapor at a temperature below the melting temperature of copper, to sinter the glass-ceramic.
Claim 2
Independent Claim
143 words
A method for producing a multilayer ceramic copper circuit board comprising the steps of: forming a multilayer structure comprising layers of copper-based paste patterns and layers of glass-ceramic, the glass-ceramic consisting of a mixture of 3% to 75% by weight of mullite, 25% to 97% by weight of borosilicate glass having a softening temperature of at least 720°C, and 0% to 70% by weight of quartz glass, based on a total weight of the glass-ceramic, blended with a binder composition containing a thermally depolymerizable resin; prefiring the multilayer structure in an inert atmosphere containing water vapor, and having a partial pressure of 0.005 to 0.3 atmosphere, at a temperature at which the thermally depolymerizable resin is eliminated; and firing the multilayer structure in an inert atmosphere containing no water vapor at a temperature below the melting temperature of copper, to sinter the glass-ceramic.
Claim 3
Dependent Claim
20 words
A method according to claim 1, wherein said thermally depolymerizable resin comprises polymethacrylate esters, polytetrafluoroethylene, poly-α-methylstyrene, or a mixture thereof.
Claim 4
Dependent Claim
43 words
A method according to claim 1, wherein said prefiring comprises a first prefiring step at 350°C to 450°C and a second prefiring step at 750°C to 900°C; and said firing is carried out at a temperature higher than 900°C and lower than 1083°C.
Claim 5
Dependent Claim
18 words
A method according to claim 1, wherein said multilayer structure is formed by a laminated green sheet technique.
Claim 6
Dependent Claim
18 words
A method according to claim 1, wherein said multilayer structure is formed by a multilayer screen printing technique.
Claim 7
Dependent Claim
72 words
A multilayer ceramic copper circuit board comprising layers of copper conductor patterns and layers of a glass-ceramic mixture of 5% to 75% by weight of mullite, 25% to 95% by weight of borosilicate glass having a softening temperature of at least 720°C, and 0% to 70% by weight of quartz glass, based on the total weight of the glass-ceramic, said glass-ceramic being sintered, the amount of residual carbon being less than 100ppm.
Claim 8
Dependent Claim
72 words
A multilayer ceramic copper circuit board comprising layers of copper conductor patterns and layers of a glass-ceramic mixture of 5% to 75% by weight of mullite, 25% to 95% by weight of borosilicate glass having a softening temperature of at least 720°C, and 0% to 70% by weight of quartz glass, based on the total weight of the glass-ceramic, said glass-ceramic being sintered, the amount of residual carbon being less than 100ppm.
References Cited (Backward Citations)
No citation records indexed.
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