US4832761A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for manufacturing gallium arsenide monolithic microwave integrated circuits using nonphotosensitive acid resist for handling
Assignee: TE Connectivity Solutions GmbH
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Filing: 1987-09-08
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Granted: 1989-05-23
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Expires: 2007-09-08
Abstract
Abstract A process for manufacturing gallium arsenide microwave circuits makes use of a nonphotosensitive acid resist as an adhesive for holding the "front side" of a gallium arsenide wafer onto a substrate while operations such as etching "via holes" into the wafer are being performed on the "back side" of the wafer. The process comprises front side processing, spinning the nonphotosensitive acid resist onto the frontside of the GaAs wafer, baking the protective acid resist coating onto the wafer, spinning the acid resist onto a substrate, joining the wafer to the substrate, thinning the wafer, and performing backside processing.
Inventors
- 👤 Arthur E. Geissberger
- 👤 Philippe R. Claytor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:52
CPC Classifications
H; H10; H10P; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10P90/1914; H10P14/00; H10P14/60; H10P14/68; H10P14/683; H10P50/00; H10P50/20; H10P50/24; H10P50/246; H10W; H10W20/00; H10W20/01; H10W20/021; Y; Y10; Y10S; Y10S148/00; Y10S148/135; Y10S438/00; Y10S438/928; Y10S438/977
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
140 words
A process for manufacturing integrated circuits comprising the steps of: providing a semiconductor wafer having a front side including metal contact pads and having a back side opposite said front side; spinning a nonphotosensitive acid resist onto said front side and baking and spinning additional acid resist onto a temporary substrate; placing said front side on the wet surface of said temporary substrate and baking to harden the adhesive acid resist; thinning said wafer to a thickness of approximately 125 um-150 um by lapping and polishing said back side; aligning and patterning an etch mask having apertures therein on the back side of the wafer; using a plasma etch to form holes in the wafer extending to said contact pads and depositing metal in said holes in contact with said pads; and removing said temporary substrate and said acid resist.
Claim 2
Dependent Claim
140 words
A process for manufacturing integrated circuits comprising the steps of: providing a semiconductor wafer having a front side including metal contact pads and having a back side opposite said front side; spinning a nonphotosensitive acid resist onto said front side and baking and spinning additional acid resist onto a temporary substrate; placing said front side on the wet surface of said temporary substrate and baking to harden the adhesive acid resist; thinning said wafer to a thickness of approximately 125 um-150 um by lapping and polishing said back side; aligning and patterning an etch mask having apertures therein on the back side of the wafer; using a plasma etch to form holes in the wafer extending to said contact pads and depositing metal in said holes in contact with said pads; and removing said temporary substrate and said acid resist.
Claim 3
Dependent Claim
11 words
The process of claim 1 wherein said temporary substrate is sapphire.
Claim 4
Dependent Claim
23 words
The process of claim 1 wherein said acid resist is impervious to acid and does not change its chemical composition upon photographic exposure.
References Cited (Backward Citations)
US3647581A
Cited
US3621565A
Cited
US3846198A
Cited
US3959045A
Cited
US4025793A
Cited
US4118857A
Cited
US4147584A
Cited
US4142925A
Cited
US4293587A
Cited
US4329779A
Cited
US4621019A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-05-22 | 1992-11-21 | 1993-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-22 | 1996-11-21 | 1997-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-22 | 2000-11-21 | 2001-05-23 | $7700.00 | Window Closed / Lapsed |