US4187599A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device having a tin metallization system and package containing same
Assignee: Motorola Solutions Inc
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Filing: 1978-05-22
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Granted: 1980-02-12
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Expires: 1998-05-22
Abstract
Abstract An improved metallization system for semiconductor substrates comprising successive layers of at least one barrier metal and tin is disclosed. A semiconductor package comprising a housing of impervious material, a semiconductor device having the metallization system of this invention disposed in the housing and conductor means bonded to the tin on the semiconductor device is also disclosed. The system is of particular usefulness in double stud diode packages.
Inventors
- 👤 Dervin L. Flowers
- 👤 Richard L. Greeson
- 👤 V. Louise Rice
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:50
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/01; H10W72/012; H10W76/00; H10W76/10; H10W76/12; H10W76/13; H10W76/138; H10W76/161; H10W72/019; H10W72/20; H10W72/251; H10W72/90; H10W72/921; H10W72/923; H10W72/951; H10W72/952
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
164 words
A method of encapsulating a semiconductor device comprising: providing a semiconductor device comprising a body of a first conductivity type, having first and second major surfaces, a region of second conductivity type in said body at a first major surface and forming a PN junction at said first surface, and an insulating layer covering said body and said PN junction at said first surface, a barrier metal on said second region at said first surface, and a barrier metal on said second major surface; selectively electroplating a layer of silver on said barrier metal using said insulator as a mask, said silver forming a bump extending above said insulator; selectively electroplating a layer of tin on said silver bump using said insulating layer as a mask; providing a glass housing and conductor means for making electrical contacts external to said housing; and heating said assembly to metallurgically bond said conductor means to said tin layer and simultaneously said semiconductor device in said glass housing.
Claim 2
Independent Claim
164 words
A method of encapsulating a semiconductor device comprising: providing a semiconductor device comprising a body of a first conductivity type, having first and second major surfaces, a region of second conductivity type in said body at a first major surface and forming a PN junction at said first surface, and an insulating layer covering said body and said PN junction at said first surface, a barrier metal on said second region at said first surface, and a barrier metal on said second major surface; selectively electroplating a layer of silver on said barrier metal using said insulator as a mask, said silver forming a bump extending above said insulator; selectively electroplating a layer of tin on said silver bump using said insulating layer as a mask; providing a glass housing and conductor means for making electrical contacts external to said housing; and heating said assembly to metallurgically bond said conductor means to said tin layer and simultaneously said semiconductor device in said glass housing.
Claim 3
Dependent Claim
35 words
The process of claim 1 further including simultaneously electroplating a layer of tin over said silver bump and over said barrier metal on said second major surface by providing an A.C. component during said electroplating.
Claim 4
Independent Claim
25 words
The method of claims 1 or 2, further including masking the barrier metal on said second major surface during the electroplating of said silver bump.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-02-11 | 1983-08-13 | 1984-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-11 | 1987-08-13 | 1988-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-11 | 1991-08-13 | 1992-02-12 | $7700.00 | Window Closed / Lapsed |