EP0186550B1
Expired / Lapsed
EP
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Process for producing multilayer ceramic circuit board with copper
Assignee: Fujitsu Ltd
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Filing: 1985-11-27
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Granted: 1992-03-25
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Expires: 2005-11-27
Abstract
No abstract record available.
Inventors
- 👤 Yoshihiko Imanaka
- 👤 Hiromi Ogawa
- 👤 Mineharu Tsukada
- 👤 Etsuro Udagawa
- 👤 Kazuaki Kurihara
- 👤 Hiromitsu Yokoyama
- 👤 Nobuo Kamehara
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 04:20
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H10W70/098; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H05K1/09; H05K1/092; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49144; Y10T29/49155; Y10T29/49158
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
129 words
A process for producing a multilayer ceramic circuit board with copper comprising the steps of : forming green sheets by doctoring a slurry of an organic solvent system which comprises 100 parts by weight of glass ceramic particles, 5 to 20 parts by weight of a thermally depolymerizable resin binder, 2 to 10 parts by weight of a plasticizer, and 0.5 to 2 parts by weight of a fatty acid ethylene oxide adduct type defloculant, said glass ceramic comprising 20 to 70% by weight of alumina; and 30 to 80% by weight of SiO₂-B₂O₃ type glass; forming via holes through said green sheets; screen-printing a copper paste on said green sheets; laminating said green sheets, thereby forming a multilayer structure; and firing said multilayer structure in a non-oxidizable atmosphere.
Claim 2
Dependent Claim
31 words
A process according to claim 1, wherein said defloculant is a fatty acid ethylene oxide adduct, preferably, an unsaturated fatty acid ethylene oxide adduct, most preferably, oleic acid ethylene oxide adduct.
Claim 3
Dependent Claim
26 words
A process according to claim 1, wherein said thermally depolymerizable resin is a polymethacrylate resin, a polytetrafluorethylene resin, a poly-α-methyl styrene resin or a mixture thereof.
Claim 4
Dependent Claim
53 words
A process according to claim 1, wherein said SiO₂-B₂O₃ type glass contains a first component having a softening point higher than the melting point of copper and, the slurry comprises as a second component, at least one of non-crystallizable and crystallizable glasses having a softening point lower than the melting point of copper.
Claim 5
Dependent Claim
14 words
A process according to claim 4, wherein said non-crystallizable glass is borosilicate or aluminoborosilicate.
Claim 6
Dependent Claim
14 words
A process according to claim 4, wherein said crystallizable glass is cordierite or spodumene.
Claim 7
Dependent Claim
107 words
A process according to claim 1, wherein said firing comprises the steps of : prefiring said multilayer structure in an inert atmosphere containing water vapor, the partial pressure of which is 5·10² - 3·10⁴ Pa (0.005 to 0.3 atmosphere), first at a temperature of 350°C to 450°C where said binder resin thermally depolymerizes, then at a temperature of 650°C to 900°C where residual organic substance which was not burnt out in the first steps reacts with water vapor to be eliminated; and firing said multilayer structure in an inert atmosphere without water vapor at a temperature higher than 950°C and lower than the melting point of copper.
Claim 8
Dependent Claim
23 words
A process according to claim 1 or 2, wherein said fatty acid ethylene oxide adduct has a molecular weight of 150 to 800.
References Cited (Backward Citations)
No citation records indexed.
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