US4908086A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-cost semiconductor device package process
Assignee: National Semiconductor Corp
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Filing: 1985-06-24
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Granted: 1990-03-13
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Expires: 2005-06-24
Abstract
Abstract An adhesive composition for attaching semiconductor die to a substate of a semiconductor device package includes a crosslinkable resinous polyimide, and an aminosilane cross-linking agent. For applications where backside contact to the semiconductor die is desired, the composition also contains finely divided conductive metal, such as silver flakes. When used in a novel process in which the adhesive composition is placed on the semiconductor device substrate prior to gelling, outgassed, a semiconductor die is placed on the outgassed composition, and the composition cured, the resulting semiconductor device package meets military specifications with a substantial cost reduction.
Inventors
- 👤 Gary B. Goodrich
- 👤 Jadish G. Belani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:50
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067; H; H01; H01B; H01B1/00; H01B1/20; H01B1/22; H10; H10W; H10W20/00; H10W20/40; H10W70/00; H10W70/60; H10W70/67; H10W70/68; H10W70/682; H10W72/00; H10W72/071; H10W72/073; H10W72/07331; H10W72/07336; H10W72/07337; H10W72/07338; H10W72/30; H10W72/351; H10W72/353; H10W72/354; H10W72/50; H10W72/531; H10W72/5363; H10W72/551; H10W72/552; H10W72/5524; H10W72/851; H10W72/874; H10W72/884; H10W90/00; H10W90/701; H10W90/731; H10W90/734; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
138 words
A process for encapsulating a semiconductor die, which comprises: adding an alkylaminotrialkoxysilane crosslinking agent to a crosslinkable resinous polyimide precursor which will cure to give a polyimide having a recurring unit of the formula: ##STR2## in which R 1 and R 2 are radicals of a tetravalent aromatic group and a divalent aromatic group, respectively, and n is a positive integer, degassing the resulting composition, applying the degassed composition to a substrate prior to gelling of the composition, positioning the semiconductor die on the substrate, curing the degassed composition to attach the semiconductor die to the substrate, applying an enclosure over the semiconductor die on the substrate, and hermetically sealing the attached semiconductor die by bonding the enclosure to the substrate over the semiconductor die through application of heat at a temperature of at least about 450° C.
Claim 2
Dependent Claim
138 words
A process for encapsulating a semiconductor die, which comprises: adding an alkylaminotrialkoxysilane crosslinking agent to a crosslinkable resinous polyimide precursor which will cure to give a polyimide having a recurring unit of the formula: ##STR2## in which R 1 and R 2 are radicals of a tetravalent aromatic group and a divalent aromatic group, respectively, and n is a positive integer, degassing the resulting composition, applying the degassed composition to a substrate prior to gelling of the composition, positioning the semiconductor die on the substrate, curing the degassed composition to attach the semiconductor die to the substrate, applying an enclosure over the semiconductor die on the substrate, and hermetically sealing the attached semiconductor die by bonding the enclosure to the substrate over the semiconductor die through application of heat at a temperature of at least about 450° C.
Claim 3
Dependent Claim
15 words
The process of claim 1 in which the degassing is carried out in a vacuum.
Claim 4
Dependent Claim
34 words
The process of claim 1 additionally comprising the step of adding a sufficient amount of a finely divided conductive metal to render the composition conductive in the cured state prior to degassing the composition.
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) | 1993-03-12 | 1993-09-11 | 1994-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-12 | 1997-09-11 | 1998-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-12 | 2001-09-11 | 2002-03-13 | $7700.00 | Window Closed / Lapsed |