US5672226A
Expired / Lapsed
US
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Process of forming multilayer circuit boards
Assignee: Delphi Technologies Inc
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Filing: 1995-10-11
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Granted: 1997-09-30
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Expires: 2015-10-11
Abstract
Abstract A process is provided for forming multilayer laminated circuit boards characterized by high circuit component density. The process generally employs a pair of plies, each of which is formed to include a dielectric prepreg bonded to a conductive foil. Vias are formed through the dielectric prepregs and conductive foils, and then filled with a conductive material, such as a conductive adhesive or conductive ink, such that the conductive material electrically contacts the conductive foils. Finally, the plies are laminated to opposing surfaces of a clad core laminate composed of a dielectric core between a pair of conductive claddings. The plies are laminated to the core laminate such that the prepregs overlay the conductive claddings of the core laminate. In so doing, the conductive material within the vias electrically contacts the pair of conductive claddings of the core laminate, thereby electrically interconnecting the conductive claddings of the core laminate with the conductive foils.
Inventors
- 👤 Joan Sharon Deardorf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:31
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/46; H05K3/4611; H05K3/4614; H05K3/4644; H05K3/4652; H05K2201/00; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0355; H05K2203/00; H05K2203/06; H05K2203/063; H05K3/40; H05K3/4038; H05K3/4053; H05K3/4069; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49126
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
154 words
A process for forming a multilayer laminated circuit board, the process comprising the steps of: providing a first dielectric layer bonded to a first conductive foil to form a first ply, and a second dielectric layer bonded to a second conductive foil to form a second ply; forming vias through the first and second dielectric layers and through the first and second conductive foils; filling the vias with a conductive material such that the conductive material electrically contacts the first and second conductive foils; and then laminating the first and second plies to opposing surfaces of a clad core laminate comprising a dielectric core between a pair of conductive claddings, the first and second plies being laminated to the clad core laminate such that the first and second dielectric layers overlay the pair of conductive claddings, the conductive material within the vias electrically contacting the pair of conductive claddings of the clad core laminate.
Claim 2
Dependent Claim
154 words
A process for forming a multilayer laminated circuit board, the process comprising the steps of: providing a first dielectric layer bonded to a first conductive foil to form a first ply, and a second dielectric layer bonded to a second conductive foil to form a second ply; forming vias through the first and second dielectric layers and through the first and second conductive foils; filling the vias with a conductive material such that the conductive material electrically contacts the first and second conductive foils; and then laminating the first and second plies to opposing surfaces of a clad core laminate comprising a dielectric core between a pair of conductive claddings, the first and second plies being laminated to the clad core laminate such that the first and second dielectric layers overlay the pair of conductive claddings, the conductive material within the vias electrically contacting the pair of conductive claddings of the clad core laminate.
Claim 3
Dependent Claim
24 words
A process as recited in claim 1 wherein the forming step includes forming the vias to extend through their respective first and second plies.
Claim 4
Dependent Claim
29 words
A process as recited in claim 1 wherein the first and second dielectric layers are formed from a material chosen from the group consisting of glass-reinforced epoxies and polyimides.
Claim 5
Dependent Claim
26 words
A process as recited in claim 1 wherein the first and second dielectric layers have a thickness of about twenty-five to about one hundred seventy-five micrometers.
Claim 6
Dependent Claim
28 words
A process as recited in claim 1 wherein the conductive material used to fill the vias is chosen from the group consisting of conductive adhesives and conductive inks.
Claim 7
Dependent Claim
27 words
A process as recited in claim 1 wherein the forming step includes forming the vias to have diameters of about one hundred to about three hundred micrometers.
Claim 8
Dependent Claim
16 words
A process as recited in claim 1 wherein the clad core laminate is a cured laminate.
Claim 9
Dependent Claim
31 words
A process as recited in claim 1 wherein the conductive material within the vias substantially prevents flow of the first and second dielectric layers into the vias during the laminating step.
Claim 10
Dependent Claim
174 words
A process for forming a multilayer laminated circuit board, the process comprising the steps of: providing a first uncured dielectric layer bonded to a first conductive foil to form a first ply, and a second uncured dielectric layer bonded to a second conductive foil to form a second ply; forming vias through the first and second plies so as to extend through the first and second conductive foils; filling the vias with a conductive material such that the conductive material electrically contacts the first and second conductive foils; providing a cured core laminate having a dielectric core between a pair of patterned conductive claddings each of the patterned conductive claddings defining at least one conductive runner; and then laminating the first and second plies to opposing surfaces of the cured core laminate such that the first and second dielectric layers overlay the pair of patterned conductive claddings and flow into voids adjacent the conductive runners, the conductive material within the vias electrically contacting the pair of patterned conductive claddings of the cured core laminate.
Claim 11
Dependent Claim
174 words
A process for forming a multilayer laminated circuit board, the process comprising the steps of: providing a first uncured dielectric layer bonded to a first conductive foil to form a first ply, and a second uncured dielectric layer bonded to a second conductive foil to form a second ply; forming vias through the first and second plies so as to extend through the first and second conductive foils; filling the vias with a conductive material such that the conductive material electrically contacts the first and second conductive foils; providing a cured core laminate having a dielectric core between a pair of patterned conductive claddings each of the patterned conductive claddings defining at least one conductive runner; and then laminating the first and second plies to opposing surfaces of the cured core laminate such that the first and second dielectric layers overlay the pair of patterned conductive claddings and flow into voids adjacent the conductive runners, the conductive material within the vias electrically contacting the pair of patterned conductive claddings of the cured core laminate.
Claim 12
Dependent Claim
29 words
A process as recited in claim 9 wherein the first and second dielectric layers are formed from a material chosen from the group consisting of glass-reinforced epoxies and polyimides.
Claim 13
Dependent Claim
26 words
A process as recited in claim 9 wherein the first and second dielectric layers have a thickness of about twenty-five to about one hundred seventy-five micrometers.
Claim 14
Dependent Claim
41 words
A process as recited in claim 9 wherein the conductive material used to fill the vias is a conductive adhesive and wherein the forming step includes forming the vias to have diameters of about two hundred to about three hundred micrometers.
Claim 15
Dependent Claim
41 words
A process as recited in claim 9 wherein the conductive material used to fill the vias is a conductive ink and wherein the forming step includes forming the vias to have diameters of about one hundred to about three hundred micrometers.
Claim 16
Dependent Claim
31 words
A process as recited in claim 9 wherein the conductive material within the vias substantially prevents flow of the first and second dielectric layers into the vias during the laminating step.
Claim 17
Dependent Claim
253 words
A process for forming a multilayer laminated circuit board, the process comprising the steps of: providing a first uncured dielectric layer bonded to a first conductive foil to form a first ply, and a second uncured dielectric layer bonded to a second conductive foil to form a second ply, the first and second uncured dielectric layers being formed from an epoxy resin and having thicknesses of about twenty-five to about one hundred seventy-five micrometers, the first and second conductive foils having thicknesses of at least about eighteen micrometers; drilling vias through the first and second plies so as to extend through the first and second conductive foils, the vias having diameters of about one hundred to about three hundred micrometers; filling the vias with a conductive material containing a metal chosen from the group consisting of silver, gold, nickel and copper, the conductive material electrically contacting the first and second conductive foils; providing a cured core laminate having a dielectric core between a pair of patterned conductive claddings, each of the patterned conductive claddings defining at least one conductive runner; and then laminating the first and second plies to opposing surfaces of the cured core laminate such that the first and second dielectric layers overlay the pair of patterned conductive claddings and flow into voids adjacent the conductive runners, the conductive material within the vias electrically contacting the pair of patterned conductive claddings of the cured core laminate while simultaneously preventing flow of the first and second uncured dielectric layers into the vias.
Claim 18
Dependent Claim
253 words
A process for forming a multilayer laminated circuit board, the process comprising the steps of: providing a first uncured dielectric layer bonded to a first conductive foil to form a first ply, and a second uncured dielectric layer bonded to a second conductive foil to form a second ply, the first and second uncured dielectric layers being formed from an epoxy resin and having thicknesses of about twenty-five to about one hundred seventy-five micrometers, the first and second conductive foils having thicknesses of at least about eighteen micrometers; drilling vias through the first and second plies so as to extend through the first and second conductive foils, the vias having diameters of about one hundred to about three hundred micrometers; filling the vias with a conductive material containing a metal chosen from the group consisting of silver, gold, nickel and copper, the conductive material electrically contacting the first and second conductive foils; providing a cured core laminate having a dielectric core between a pair of patterned conductive claddings, each of the patterned conductive claddings defining at least one conductive runner; and then laminating the first and second plies to opposing surfaces of the cured core laminate such that the first and second dielectric layers overlay the pair of patterned conductive claddings and flow into voids adjacent the conductive runners, the conductive material within the vias electrically contacting the pair of patterned conductive claddings of the cured core laminate while simultaneously preventing flow of the first and second uncured dielectric layers into the vias.
References Cited (Backward Citations)
US5463191A
Cited
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