EP0425148A2
Expired / Lapsed
EP
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Method of forming multilayer thick film circuits
Assignee: AT&T Inc
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Filing: 1990-10-12
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Granted: —
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Expires: 2010-10-12
Abstract
Abstract Disclosed is a method of forming multilayer thick film circuits. Each layer is formed from a ceramic green sheet (10-13) with appropriate conductive patterns (14) on the surface. The sheets are laminated by means of an isostatic pressure process which uses a gas as the pressing medium. The layers are subsequently co-fired to form the final article.
Inventors
- 👤 Mark Steven O'brien
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 02:34
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/46; H05K3/4611; H05K3/4626; H05K3/4629; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H05K1/00; H05K1/02; H05K1/03; H05K1/0306; H05K1/09; H05K1/092; H05K1/16; H05K2203/00; H05K2203/06; H05K2203/068
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
77 words
A method of fabricating multilayer thick film circuits comprising the steps of: providing a plurality of ceramic green sheets (10-13) each with conductive patterns (14) on at least one major surface thereof; and CHARACTERIZED in the steps of stacking said sheets within a chamber (33) and introducing therein a gas which provides sufficient pressure isostatically to said sheets to cause adherence between the sheets; and subsequently heating the resulting structure to sinter together the plurality of sheets.
Claim 2
Independent Claim
77 words
A method of fabricating multilayer thick film circuits comprising the steps of: providing a plurality of ceramic green sheets (10-13) each with conductive patterns (14) on at least one major surface thereof; and CHARACTERIZED in the steps of stacking said sheets within a chamber (33) and introducing therein a gas which provides sufficient pressure isostatically to said sheets to cause adherence between the sheets; and subsequently heating the resulting structure to sinter together the plurality of sheets.
Claim 3
Dependent Claim
19 words
The method according to claim 1 wherein the gas is selected from the group consisting of air and nitrogen.
Claim 4
Dependent Claim
17 words
The method according to claim 1 wherein the pressure is within the range 150 to 250 Kg/cm².
Claim 5
Dependent Claim
23 words
The method according to claim 1 wherein, prior to applying the pressure isostatically, the stack of sheets is subjected to a uniaxial pressure.
Claim 6
Dependent Claim
18 words
The method according to claim 4 wherein the uniaxial pressure is within the range 25 to 75 Kg/cm².
Claim 7
Dependent Claim
21 words
The method according to claim 1 wherein the sheets are stacked within the chamber without any compliant bag surrounding the sheets.
Claim 8
Dependent Claim
38 words
The method according to claim 3 wherein the stacks are held at a temperature within the range 50 degrees C to 110 degrees C and pressure is applied for a time within the range 5 to 15 minutes.
References Cited (Backward Citations)
No citation records indexed.
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