EP0163548A2
Expired / Lapsed
EP
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Method for producing multilayer ceramic circuit board
Assignee: Fujitsu Ltd
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Filing: 1985-05-31
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Granted: —
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Expires: 2005-05-31
Abstract
Abstract A method for producing a multilayer ceramic circuit board includes the steps of forming a multilayer structure consisting of glass-ceramic layers and patterns of copper-based paste, the glass-ceramic layers consisting of a mixture of 10 per cent to 75 per cent by weight of α-alumina, 20 per cent to 60 per cent by weight of crystallisable or noncrystallisable glass which can be sintered at a temperature lower than the melting point of copper, and 5 per cent to 70 per cent by weight of quartz glass, based on the total weight of the glass-ceramic material present, blended with a binder containing a thermally depolymerisable resin; prefiring the multilayer structure in an inert atmosphere containing water vapour, the partial pressure of which is 0.005 to 0.3 atmosphere, at a temperature at which the thermally de-. polymerisable resin is eliminated from the structure; and firing the multilayer structure in an inert atmosphere containing no water vapour at a temperature below the melting point of copper so as to sinter the glass-ceramic layers.
Inventors
- 👤 Kazuaki Kurihara
- 👤 Nobuo Kamehara
- 👤 Hiromitsu Yokoyama
- 👤 Hiromi Ogawa
- 👤 Kishio Yokouchi
- 👤 Yoshihiko Imanaka
- 👤 Koichi Niwa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 06:03
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/46; H05K3/4644; H05K3/4664; H05K3/4667; C; C03; C03C; C03C10/00; C03C10/0009; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H05K3/4611; H05K3/4626; H05K3/4629; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H10W70/098; H10W70/60; H10W70/67; H10W70/69; H10W70/692; C03C2214/00; C03C2214/04; C03C2214/20; H05K1/09; H05K1/092; H05K2203/00; H05K2203/08; H05K2203/086; H05K2203/088; H05K2203/11; H05K2203/1126; H05K3/10; H05K3/12; H05K3/1283; H05K3/1291; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T428/00; Y10T428/24; Y10T428/24273; Y10T428/24322; Y10T428/24802; Y10T428/24917; Y10T428/24926; Y10T428/25; Y10T428/252
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
174 words
A method for producing a multilayer ceramic circuit board for use with copper conductors comprising the steps of: forming a multilayer structure consisting of glass-ceramic layers and patterns of copper-based paste, the glass-ceramic layers consisting of a mixture of 10 per cent to 75 per cent by weight of α-alumina, 20 per cent to 60 per cent by weight of crystallisable or noncrystallisable glass which can be sintered at a temperature lower than the melting point of copper, and 5 per cent to 70 per cent by weight of quartz glass, based on the total weight of the glass-ceramic material present, blended with a binder containing a thermally depolymerisable resin; prefiring the multilayer structure in an inert atmosphere containing water vapour, the partial pressure of which is 0.005 to 0.3 atmosphere, at a temperature at which the thermally depolymerisable resin is eliminated from the structure; and firing the multilayer structure in an inert atmosphere containing no water vapour at a temperature below the melting point of copper so as to sinter the glass-ceramic layers.
Claim 2
Independent Claim
174 words
A method for producing a multilayer ceramic circuit board for use with copper conductors comprising the steps of: forming a multilayer structure consisting of glass-ceramic layers and patterns of copper-based paste, the glass-ceramic layers consisting of a mixture of 10 per cent to 75 per cent by weight of α-alumina, 20 per cent to 60 per cent by weight of crystallisable or noncrystallisable glass which can be sintered at a temperature lower than the melting point of copper, and 5 per cent to 70 per cent by weight of quartz glass, based on the total weight of the glass-ceramic material present, blended with a binder containing a thermally depolymerisable resin; prefiring the multilayer structure in an inert atmosphere containing water vapour, the partial pressure of which is 0.005 to 0.3 atmosphere, at a temperature at which the thermally depolymerisable resin is eliminated from the structure; and firing the multilayer structure in an inert atmosphere containing no water vapour at a temperature below the melting point of copper so as to sinter the glass-ceramic layers.
Claim 3
Dependent Claim
14 words
A method according to claim 1, wherein said crystallisable glass comprises cordierite or spoduemene.
Claim 4
Dependent Claim
18 words
A method according to claim 1 or 2, wherein said noncrystallisable glass comprises borosilicate glass or aluminosilicate glass.
Claim 5
Dependent Claim
24 words
A method according to claim 1, 2 or 3, wherein said thermally depolymerisable resin comprises polymethacrylate ester, polytetrafluoroethylene, poly-a -methylstyrene, or a mixture thereof.
Claim 6
Independent Claim
49 words
A method according to any preceding claim wherein: said prefiring comprises a first prefiring step at 350 o C to 450 o C and a second prefiring step at 650°C to 900°C and said firing-is carried out at a temperature higher than 900 0 C and lower than 1083°C.
Claim 7
Independent Claim
21 words
A method according to any preceding claim, wherein said multilayer structure is formed by means of a laminated green sheet technique.
Claim 8
Independent Claim
25 words
A method according to any one of claims 1 to 5, wherein said multilayer structure is formed by means of a multilayer screen printing technique.
Claim 9
Dependent Claim
77 words
A multilayer ceramic circuit board for use with copper conductors comprising a sintered mixture of 10 per cent to 75 per cent by weight of α-alumina, 20 per cent to 60 per cent by weight of crystallisable or noncrystallisable glass which can be sintered at a temperature lower than the melting point of copper, and 5 per cent to 70 per cent by weight of quartz glass, based on the total weight of the glass-ceramic material present.
Claim 10
Dependent Claim
77 words
A multilayer ceramic circuit board for use with copper conductors comprising a sintered mixture of 10 per cent to 75 per cent by weight of α-alumina, 20 per cent to 60 per cent by weight of crystallisable or noncrystallisable glass which can be sintered at a temperature lower than the melting point of copper, and 5 per cent to 70 per cent by weight of quartz glass, based on the total weight of the glass-ceramic material present.
Claim 11
Dependent Claim
22 words
A multilayer ceramic circuit board for use with copper conductors according to claim 8, wherein said crystallisable glass comprises cordierite or spoduemene.
Claim 12
Dependent Claim
26 words
A multilayer ceramic circuit board for use with copper conductors according to claim 8 or 9, wherein said noncrystallisable glass comprises borosilicate glass or aluminosilicate glass.
References Cited (Backward Citations)
No citation records indexed.
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