Patent US4770897A successfully refreshed from Google Patents.
US4770897A
Expired / Lapsed
US
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Multilayer interconnection system for multichip high performance semiconductor packaging
Assignee: Hewlett Packard Development Co LP
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Filing: 1987-05-05
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Granted: 1988-09-13
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Expires: 2007-05-05
Abstract
Abstract A method for fabricating a multilayer interconnection system that is fully planar with completely sealed and corrosion resistant conductors separated by dielectric material.
Inventors
- 👤 Andrew L. Wu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:14
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/10; H05K3/18; H05K3/181; H05K3/182; H05K3/184; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H05K3/14; H05K3/143
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
231 words
A method for fabricating a layer of a planar multilayer interconnection system comprising: (a) forming a dielectric sub-layer overlaying a base layer, said dielectric sub-layer being nonsoluble after said layer is cured; (b) forming a sacrificial sub-layer overlaying said dielectric sub-layer, said sacrificial sub-layer being soluble after said layer is cured; (c) removing a portion of said sacrificial sub-layer to expose a portion of said dielectric sub-layer; (d) removing said exposed portion of said dielectric sub-layer and a selected portion surrounding said exposed portion of said dielectric sub-layer to expose a portion of said base layer, removal of said selected portion leaving an exposed portion of said sacrificial sub-layer overhanging said exposed portion of said base layer; (e) depositing a first conductive adhesive sub-layer overlaying said dielectric and sacrificial sub-layers and said exposed area of said base layer without overlaying said exposed overhanging portion facing the base layer of said sacrificial sub-layer; (f) depositing a conductive seeding sub-layer overlaying said first conductive adhesive sub-layer; (g) removing said sacrificial sub-layer and said first conductive adhesive sub-layer and said conductive seeding sub-layer in contact with said sacrificial sub-layer; (h) forming a conductor sub-layer by electrolessly plating a conductor sub-layer onto said seeding sub-layer; and (i) forming a second conductive adhesive sub-layer by electrolessly plating said second adhesive sub-layer onto said conductor sub-layer to form a surface which is planar with said dielectric sub-layer.
Claim 2
Independent Claim
231 words
A method for fabricating a layer of a planar multilayer interconnection system comprising: (a) forming a dielectric sub-layer overlaying a base layer, said dielectric sub-layer being nonsoluble after said layer is cured; (b) forming a sacrificial sub-layer overlaying said dielectric sub-layer, said sacrificial sub-layer being soluble after said layer is cured; (c) removing a portion of said sacrificial sub-layer to expose a portion of said dielectric sub-layer; (d) removing said exposed portion of said dielectric sub-layer and a selected portion surrounding said exposed portion of said dielectric sub-layer to expose a portion of said base layer, removal of said selected portion leaving an exposed portion of said sacrificial sub-layer overhanging said exposed portion of said base layer; (e) depositing a first conductive adhesive sub-layer overlaying said dielectric and sacrificial sub-layers and said exposed area of said base layer without overlaying said exposed overhanging portion facing the base layer of said sacrificial sub-layer; (f) depositing a conductive seeding sub-layer overlaying said first conductive adhesive sub-layer; (g) removing said sacrificial sub-layer and said first conductive adhesive sub-layer and said conductive seeding sub-layer in contact with said sacrificial sub-layer; (h) forming a conductor sub-layer by electrolessly plating a conductor sub-layer onto said seeding sub-layer; and (i) forming a second conductive adhesive sub-layer by electrolessly plating said second adhesive sub-layer onto said conductor sub-layer to form a surface which is planar with said dielectric sub-layer.
Claim 3
Dependent Claim
22 words
The method according to claim 1 where said sacrificial sub-layer is selected from the group consisting of photosensitive soluble polyimide and photoresist.
Claim 4
Dependent Claim
30 words
The method according to claim 2 where in step (c), said sacrificial sub-layer is removed by masking a portion of said sacrificial sub-layer and exposing said layer to ultraviolet light.
Claim 5
Dependent Claim
31 words
The method according to claim 1 where in step (d), said selected portions are removed so as to provide an overhang of about 3 to about 7 micrometers in lateral depth.
Claim 6
Dependent Claim
14 words
The method according to claim 1 where said first conductive adhesive sub-layer is chromium.
Claim 7
Dependent Claim
13 words
The method according to claim 1 where said conductive seeding sub-layer is copper.
Claim 8
Dependent Claim
23 words
The method according to claim 1 where said first conductive adhesive sub-layer and said conductive seeding sub-layer are applied by cold sputtering deposition.
Claim 9
Dependent Claim
12 words
The method according to claim 1 where said conductor sub-layer is copper.
Claim 10
Dependent Claim
14 words
The method according to claim 1 where said second conductive adhesive sub-layer is nickel.
Claim 11
Dependent Claim
21 words
The method according to claim 1 where each layer of a multilayer interconnection system is fabricated using steps (a) through (i).
Claim 12
Independent Claim
288 words
A method for fabricating a layer of a planar multilayer interconnection system comprising: (a) forming a polyimide sub-layer overlaying a base layer, said polyimide sub-layer being nonsoluble after said layer is cured; (b) forming a metallic sub-layer overlaying said polyimide sub-layer; (c) forming a sacrificial sub-layer overlaying said metallic sub-layer, said sacrificial sub-layer being selected from polyimides which are soluble after said layer is cured; (d) removing a portion of said sacrificial sub-layer to expose a portion of said metallic sub-layer; (e) removing said exposed portion of said metallic sub-layer to expose a portion of said polyimide sub-layer; (f) removing said exposed portion of said polyimide sub-layer and a selected portion surrounding said exposed portion of said polyimide sub-layer to expose a portion of said base layer, removal of said selected portion leaving an exposed portion of said metallic sub-layer and said sacrificial sub-layer overhanging said exposed portion of said base layer; (g) removing said portion of said metallic sub-layer overhanging said exposed portion of said base layer; (h) depositing a first conductive adhesive sub-layer overlaying said polyimide and sacrificial sub-layers and said exposed area of said base layer without overlaying said exposed overhang portion facing said base layer of said sacrificial sub-layer; (i) depositing a conductive seeding sub-layer overlaying said first conductive adhesive sub-layer; (j) removing said sacrificial sub-layer and said first conductive adhesive sub-layer and said conductive seeding sub-layer in contact with said sacrificial sub-layer; (k) removing said metallic sub-layer; (1) forming a conductor sub-layer by electrolessly plating a conductor sub-layer onto said conductive seeding sub-layer; and (m) forming a second conductive adhesive sub-layer by electrolessly plating said second adhesive sub-layer onto said conductor sub-layer to form a surface which is planar with said polyimide sub-layer.
Claim 13
Independent Claim
288 words
A method for fabricating a layer of a planar multilayer interconnection system comprising: (a) forming a polyimide sub-layer overlaying a base layer, said polyimide sub-layer being nonsoluble after said layer is cured; (b) forming a metallic sub-layer overlaying said polyimide sub-layer; (c) forming a sacrificial sub-layer overlaying said metallic sub-layer, said sacrificial sub-layer being selected from polyimides which are soluble after said layer is cured; (d) removing a portion of said sacrificial sub-layer to expose a portion of said metallic sub-layer; (e) removing said exposed portion of said metallic sub-layer to expose a portion of said polyimide sub-layer; (f) removing said exposed portion of said polyimide sub-layer and a selected portion surrounding said exposed portion of said polyimide sub-layer to expose a portion of said base layer, removal of said selected portion leaving an exposed portion of said metallic sub-layer and said sacrificial sub-layer overhanging said exposed portion of said base layer; (g) removing said portion of said metallic sub-layer overhanging said exposed portion of said base layer; (h) depositing a first conductive adhesive sub-layer overlaying said polyimide and sacrificial sub-layers and said exposed area of said base layer without overlaying said exposed overhang portion facing said base layer of said sacrificial sub-layer; (i) depositing a conductive seeding sub-layer overlaying said first conductive adhesive sub-layer; (j) removing said sacrificial sub-layer and said first conductive adhesive sub-layer and said conductive seeding sub-layer in contact with said sacrificial sub-layer; (k) removing said metallic sub-layer; (1) forming a conductor sub-layer by electrolessly plating a conductor sub-layer onto said conductive seeding sub-layer; and (m) forming a second conductive adhesive sub-layer by electrolessly plating said second adhesive sub-layer onto said conductor sub-layer to form a surface which is planar with said polyimide sub-layer.
Claim 14
Dependent Claim
15 words
The method according to claim 11 where said polyimide sub-layer is a photosensitive nonsoluble polyimide.
Claim 15
Dependent Claim
12 words
The method according to claim 11 where said metallic sub-layer is titanium.
Claim 16
Independent Claim
228 words
A method for fabricating a layer of a planar multilayer interconnection system comprising: (a) forming a silicon dioxide sub-layer overlaying a base layer; (b) forming a sacrificial sub-layer overlaying said silicon dioxide sub-layer, said sacrificial sub-layer being soluble after said layer is cured; (c) removing a portion of said sacrificial sub-layer to expose a portion of said silicon dioxide sub-layer; (d) removing said exposed portion of said silicon dioxide sub-layer and a selected portion surrounding said exposed portion of said silicon dioxide sub-layer to expose a portion of said base layer, removal of said selected portion leaving an exposed portion of said sacrificial sub-layer overhanging said exposed portion of said base layer; (e) depositing a first conductive adhesive sub-layer overlaying said silicon dioxide and sacrificial sub-layers and said exposed area of said base layer without overlaying said exposed overhang portion facing said base layer of said sacrificial sub-layer; (f) depositing a conductive seeding sub-layer overlaying said first conductive adhesive sub-layer; (g) removing said sacrificial sub-layer and said first conductive adhesive sub-layer and said conductive seeding sub-layer in contact with said sacrificial sub-layer; (h) forming a conductor sub-layer by electrolessly plating a conductor sub-layer onto said seeding sub-layer; and (i) forming a second conductive adhesive sub-layer by electrolessly plating said second adhesive sub-layer onto said conductor sub-layer to form a surface which is planar with said silicon dioxide sub-layer.
Claim 17
Independent Claim
228 words
A method for fabricating a layer of a planar multilayer interconnection system comprising: (a) forming a silicon dioxide sub-layer overlaying a base layer; (b) forming a sacrificial sub-layer overlaying said silicon dioxide sub-layer, said sacrificial sub-layer being soluble after said layer is cured; (c) removing a portion of said sacrificial sub-layer to expose a portion of said silicon dioxide sub-layer; (d) removing said exposed portion of said silicon dioxide sub-layer and a selected portion surrounding said exposed portion of said silicon dioxide sub-layer to expose a portion of said base layer, removal of said selected portion leaving an exposed portion of said sacrificial sub-layer overhanging said exposed portion of said base layer; (e) depositing a first conductive adhesive sub-layer overlaying said silicon dioxide and sacrificial sub-layers and said exposed area of said base layer without overlaying said exposed overhang portion facing said base layer of said sacrificial sub-layer; (f) depositing a conductive seeding sub-layer overlaying said first conductive adhesive sub-layer; (g) removing said sacrificial sub-layer and said first conductive adhesive sub-layer and said conductive seeding sub-layer in contact with said sacrificial sub-layer; (h) forming a conductor sub-layer by electrolessly plating a conductor sub-layer onto said seeding sub-layer; and (i) forming a second conductive adhesive sub-layer by electrolessly plating said second adhesive sub-layer onto said conductor sub-layer to form a surface which is planar with said silicon dioxide sub-layer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-13 | 1992-03-14 | 1992-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-13 | 1996-03-14 | 1996-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-13 | 2000-03-14 | 2000-09-13 | $7700.00 | Window Closed / Lapsed |