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US4937707A Expired / Lapsed US ⏱️ 0.0 years remaining

Flexible carrier for an electronic device

Assignee: International Business Machines Corp
•
Filing: 1988-05-26
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Granted: 1990-06-26
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Expires: 2008-05-26
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Abstract

Abstract The disclosure describes a form of packaging for an electronic device and a method of achieving it in order to overcome the problem of damage because of cycles in environmental temperature. A thin, flexible foil functioning as a carrier of electrically conductive material selected from the group including Invar, copper-Invar-copper and Kovar is coated with a preselected polyimide, on which is formed a thin metallized coating of chromium, in the order of 200 Angstroms, and copper, in the order of 80,000 Angstroms. A predetermined electrical circuit is formed out of this metallized coating by a photolithographic process and is connected electrically to the flexible metal foil by vias through the polyimide coating. At least one electronic device is bonded to the electrical circuit at a predetermined location to operate functionally with the circuit, and both the device and the circuit are connected electrically by the vias to the thin, metal carrier which functions as a power plane for the package.

Inventors

  • 👤 Donald G. McBride
  • 👤 Theron L. Ellis

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 03:59
CPC Classifications
H; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/05; H05K1/056; H10; H10W; H10W70/00; H10W70/40; H10W70/451; H10W90/00; H10W90/701; H10W90/721; H10W90/724

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 115 words
An electronic package assembly, comprising: a flexible carrier formed of a predetermined material that is electrically conductive and has a low coefficient of thermal expansion; a layer of electrically insulating material formed on and supported by said flexible carrier material; an electrical circuit formed on and supported by said layer of electrically insulating material, including conductors of electrically conductive material in a predetermined pattern; a predetermined electronic device bonded to said electrical circuit in a predetermined location to be operatively functional with said electrical circuit; and at least one path formed through said layer of electrically insulating material for connecting said electrical circuit at a preselected location to said flexible carrier of electrically conductive material.
Claim 2
Dependent Claim 115 words
An electronic package assembly, comprising: a flexible carrier formed of a predetermined material that is electrically conductive and has a low coefficient of thermal expansion; a layer of electrically insulating material formed on and supported by said flexible carrier material; an electrical circuit formed on and supported by said layer of electrically insulating material, including conductors of electrically conductive material in a predetermined pattern; a predetermined electronic device bonded to said electrical circuit in a predetermined location to be operatively functional with said electrical circuit; and at least one path formed through said layer of electrically insulating material for connecting said electrical circuit at a preselected location to said flexible carrier of electrically conductive material.
Claim 3
Dependent Claim 20 words
An electronic package assembly as described in claim 1 wherein said flexible carrier is formed from a material including NI/FE.
Claim 4
Dependent Claim 20 words
An electronic package assembly as described in claim 2 wherein said layer of electrically insulating material consists of a polyimide.
Claim 5
Dependent Claim 18 words
An electronic package assembly as described in claim 2 wherein said layer of electrically insulating material includes polytetrafluoroethylene.
Claim 6
Dependent Claim 61 words
An electronic package assembly as described in claim 3 wherein said layer consisting of a polyimide includes at least one via formed therethrough to connect said electrical circuit electrically to said flexible carrier; and said carrier is adapted to provide at least one terminal of electrical power to said electrical circuit and to said electronic device bonded to said electrical circuit.
Claim 7
Dependent Claim 20 words
An electronic package assembly as described in claim 1 wherein said flexible carrier is formed from a material including CU-NI/FE-CU.
Claim 8
Dependent Claim 20 words
An electronic package assembly as described in claim 1 wherein said flexible carrier is formed from a material including NI/CO/FE/MG.
Claim 9
Dependent Claim 20 words
An electronic package assembly as described in claim 1 wherein said flexible carrier is formed from a material including CU-NI/CO/FE/MG-CU.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-06-25 1993-12-25 1994-06-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-06-25 1997-12-25 1998-06-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-06-25 2001-12-25 2002-06-26 $7700.00 Window Closed / Lapsed

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