Patent EP0446656A1 successfully refreshed from Google Patents.
EP0446656A1
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Method of manufacturing a multilayer circuit board
Assignee: Rogers Corp
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Filing: 1991-02-19
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Granted: —
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Expires: 2011-02-19
Abstract
Abstract Methods of fabricating multilayer circuits are presented. In accordance with the present invention, a plurality of circuit layers comprised of a dielectric substrate having a circuit formed thereon are stacked, one on top of the other. The dielectric substrate is composed of a polymeric material capable of undergoing fusion bonding such as a fluoropolymeric based substrate. Fusible conductive bonding material (e.g. solder) is applied in selected exposed circuit traces (prior to the stacking step) whereupon the entire stack-up is subjected to lamination under heat and pressure to simultaneously fuse all of the substrate and conductive layers together to form an integral multilayer circuit having solid conductive interconnects.
Inventors
- 👤 Robert Daigle
- 👤 Samuel Malbaurn
- 👤 David Noddin
- 👤 G. Robert Traut
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 20:08
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/46; H05K3/4611; H05K3/4626; H05K3/4632; H05K3/4614; H05K3/4617; H05K2201/00; H05K2201/01; H05K2201/0104; H05K2201/0129; H05K2201/0137; H05K2201/015; H05K2201/03; H05K2201/0302; H05K2201/0305; H05K2201/09; H05K2201/09209; H05K2201/095; H05K2201/09563; H05K2203/00; H05K2203/15; H05K2203/1572; H05K3/10; H05K3/20; H05K3/205; H05K3/22; H05K3/28; H05K3/40; H05K3/4038; H05K3/42; H05K3/423; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49126; Y10T29/49155; Y10T29/49158; Y10T29/53; Y10T29/5313; Y10T29/53174; Y10T428/00; Y10T428/31504; Y10T428/3154; Y10T428/31544
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
162 words
A method of making a multilayer circuit comprising the steps of : providing at least two circuit boards wherein said first circuit board comprises a first substrate of fusible dielectric material and a first conductive circuit formed thereon and said second circuit board comprises a second substrate of fusible dielectric material and a second conductive circuit formed thereon and wherein at least said first conductive circuit includes fusible conductive material provided on at least one selected location thereof; stacking said at least two circuit boards one on top of the other so that said fusible conductive material on said first circuit aligns with a selected location on said second circuit; laminating said stacked circuit boards under heat and pressure effective to fuse both said fusible dielectric material and said fusible conductive material so as to form a cohesive multilayer circuit having a solid conductive interconnect between said first and second circuits, said solid conductive interconnect being defined by said fusible conductive material.
Claim 2
Dependent Claim
93 words
A method in accordance with claim 1 wherein at least one of said two circuit boards are formed using the steps of : forming a circuit pattern; forming a fusible dielectric substrate having opposed first and second surfaces, said circuit pattern being located on said first surface of said substrate; forming at least one access opening through said second surface of said substrate to expose a selected location in said circuit pattern; filling said access opening with conductive material wherein at least an upper portion of said filled access opening comprises fusible material.
Claim 3
Dependent Claim
20 words
A method in accordance with claim 2 wherein : a lower portion of said access opening comprises non-fusible conductive material.
Claim 4
Dependent Claim
29 words
A method in accordance with claim 2 including the step of : forming said circuit pattern on a mandrel prior to forming said dielectric substrate on said circuit pattern.
Claim 5
Dependent Claim
24 words
A method in accordance with claim 4 including the step of : removing the mandrel subsequent to filling the access opening with conductive material.
Claim 6
Dependent Claim
35 words
A method in accordance with claim 1 including the step of : forming said fusible conductive material as a plug in a sheet of fusible dielectric material which is sandwiched between said two circuit boards.
Claim 7
Dependent Claim
38 words
A method in accordance with claim 1 wherein : said access opening is formed by at least one of the opening formation techniques selected from the group consisting of laser drilling, mechanical drilling, plasma etching and ion etching.
Claim 8
Dependent Claim
17 words
A method in accordance with claim 1 wherein : said fusible dielectric material comprises a fluoropolymeric material.
Claim 9
Dependent Claim
17 words
A method in accordance with claim 8 wherein : said fluoropolymeric material comprises a polytetrafluoroethylene based material.
Claim 10
Dependent Claim
19 words
A method in accordance with claim 1 wherein : said fusible conductive material comprises a metal or metal alloy.
Claim 11
Dependent Claim
22 words
A method in accordance with claim 10 wherein : said fusible conductive material has a melting point of less than 482 °C;
Claim 12
Dependent Claim
21 words
A method in accordance with claim 1 wherein said heat is in the temperature range of 325 °C to 425 °C.
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