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US4743568A Expired / Lapsed US ⏱️ 0.0 years remaining

Multilevel interconnect transfer process

Assignee: NXP USA Inc
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Filing: 1987-07-24
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Granted: 1988-05-10
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Expires: 2007-07-24
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Abstract

Abstract A method for processing multilevel interconnect lines separately from the multichip module on which they are to be employed. An oxide layer (16) is grown on a silicon wafer (14) and followed by a polyimide layer (18). Then a metal layer (20) is deposited and patterned. This is followed by another polyimide layer (24) having vias and another patterned metal layer (28). The vias allow for connections to be made between metal layers. Many polyimides and metal layers may be processed to allow for the desired number of levels of interconnect lines. After a last polyimide layer (32) is deposited, the oxide layer is etched to separate the multilevel interconnect line transfer (34) from the silicon wafer. After the processing of the multilevel interconnect lines, the multilevel interconnect line transfer is adhered to the multichip module in a predetermined relationship and electrical connections are made between them. In an alternative embodiment, a boron nitride layer (46) is bonded on a surface of silicon wafer (14). Stabilizing ring (44) is bonded on a second surface of the silicon wafer. Exposed regions of the wafer are etched away. The processing of multilevel interconnect line transfer (34) occurs on boron nitride layer (46) in the same manner as previously described.

Inventors

  • 👤 Thomas E. Wood

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 18:03
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/70; H10P72/74; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/069; H10W20/40; H10W70/00; H10W70/60; H10W70/611; H10W70/614; H10P72/7424; Y; Y10; Y10S; Y10S148/00; Y10S148/135

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 89 words
A method of processing and transferring multilevel interconnect lines for use in a module having a plurality of electrical contacts incorporated therein comprising the steps of: providing a substrate; forming a separation layer on said substrate; forming multilevel interconnect lines on said separation layer; separating, at least partially, said substrate and said multilevel interconnect lines; adhering said multilevel interconnect lines and a module having a plurality of electrical contacts in a predetermined relationship; and electrically connecting said multilevel interconnect lines and said plurality of electrical contacts of said module.
Claim 2
Independent Claim 89 words
A method of processing and transferring multilevel interconnect lines for use in a module having a plurality of electrical contacts incorporated therein comprising the steps of: providing a substrate; forming a separation layer on said substrate; forming multilevel interconnect lines on said separation layer; separating, at least partially, said substrate and said multilevel interconnect lines; adhering said multilevel interconnect lines and a module having a plurality of electrical contacts in a predetermined relationship; and electrically connecting said multilevel interconnect lines and said plurality of electrical contacts of said module.
Claim 3
Dependent Claim 20 words
The method of claim 1 wherein the step of separating includes completely separating the substrate and the multilevel interconnect lines.
Claim 4
Dependent Claim 15 words
The method of claim 1 wherein the separation layer is comprised of a thermal oxide.
Claim 5
Dependent Claim 15 words
The method of claim 3 wherein the step of separating includes etching the separation layer.
Claim 6
Dependent Claim 50 words
The method of claim 3 further including the steps of: adhering stabilizing means to the multilevel interconnect lines after said multilevel interconnect lines have been partially separated from the substrate; etching the separation layer further to completely separate said multilevel interconnect lines from said substrate; and removing said stabilizing means.
Claim 7
Dependent Claim 131 words
The method of claim 1 wherein the forming multilevel interconnect lines step further includes the steps of: forming a first polymer layer on the separation layer of the substrate; forming a first conductor layer on said first polymer layer; patterning a first resist layer on said first conductor layer; etching said first conductor layer using said first resist layer as an etch mask; removing said first resist layer; forming a second polymer layer, said second polymer layer having vias which extend to said first conductor layer; forming a second conductor layer on said second polymer layer; patterning a second resist layer on said second conductor layer; etching said second conductor layer using said second resist layer as an etch mask; removing said second resist layer; and forming a last polymer layer.
Claim 8
Dependent Claim 40 words
The method of claim 6 wherein the steps of forming a second polymer layer, forming a second conductor layer, patterning a second resist layer, etching said second conductor layer and removing said second resist layer are performed more than once.
Claim 9
Dependent Claim 26 words
The method of claim 4 wherein the step of separating includes employing an etchant consisting essentially of HCl, HF, HNO 3 and distilled H 2 O.
Claim 10
Dependent Claim 28 words
The method of claim 8 wherein the etchant consists essentially of 75 parts HCl, 50 parts HF, 125 parts HNO 3 and 305 parts distilled H 2 O.
Claim 11
Independent Claim 125 words
A method of processing and transferring multilevel interconnect lines for use in a module having a plurality of electrical contacts incorporated therein comprising the steps of: providing a substrate having a first surface and a second surface; forming a boron nitride layer on said first surface of said substrate; bonding stabilizing means on said second surface of said substrate; removing the portions of said substrate left exposed by said stabilizing means; forming multilevel interconnect lines on said boron nitride layer; adhering said multilevel interconnect lines including said boron nitride layer and said stabilizing means to a module having a plurality of electrical contacts, said multilevel interconnect lines and said module being in a predetermined relationship; and electrically connecting said multilevel interconnect lines and said module.
Claim 12
Independent Claim 125 words
A method of processing and transferring multilevel interconnect lines for use in a module having a plurality of electrical contacts incorporated therein comprising the steps of: providing a substrate having a first surface and a second surface; forming a boron nitride layer on said first surface of said substrate; bonding stabilizing means on said second surface of said substrate; removing the portions of said substrate left exposed by said stabilizing means; forming multilevel interconnect lines on said boron nitride layer; adhering said multilevel interconnect lines including said boron nitride layer and said stabilizing means to a module having a plurality of electrical contacts, said multilevel interconnect lines and said module being in a predetermined relationship; and electrically connecting said multilevel interconnect lines and said module.
Claim 13
Dependent Claim 14 words
The method of claim 10 further comprising the step of removing the stabilizing means.
Claim 14
Dependent Claim 29 words
The method of claim 11 wherein the step of forming multilevel interconnect lines is performed before the steps of bonding stabilizing means and removing the portions of said substrate.
Claim 15
Dependent Claim 130 words
The method of claim 10 wherein the step of forming multilevel interconnect lines further includes the steps of: forming a first polymer layer on the boron nitride layer; forming a first conductive layer on said first polymer layer; patterning a first resist layer on said first conductive layer; etching said first conductive layer using said first resist layer as an etch mask; removing said first resist layer; forming a second polymer layer, said second polymer layer having vias which extend to said first conductive layer; forming a second conductive layer on said second polymer layer; patterning a second resist layer on said second conductive layer; etching said second conductive layer using said second resist layer as an etch mask; removing said second resist layer; and forming a last polymer layer.
Claim 16
Dependent Claim 40 words
The method of claim 13 wherein the steps of forming a second polymer layer, forming a second conductive layer, patterning a second resist layer, etching said second conductive layer and removing said second resist layer are performed more than once.

References Cited (Backward Citations)

US4251852A Cited
US4377316A Cited
US4420203A Cited
US4446477A Cited
US4480288A Cited
US4630096A Cited
US4698662A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-05-10 1991-11-09 1992-05-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-05-10 1995-11-09 1996-05-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-05-10 1999-11-09 2000-05-10 $7700.00 Window Closed / Lapsed

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