US4400870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of hermetically encapsulating a semiconductor device by laser irradiation
Assignee: Texas Instruments Inc
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Filing: 1980-10-06
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Granted: 1983-08-30
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Expires: 2000-10-06
Abstract
Abstract A hermetic seal is formed without expensive precious metals by fusing two members of a semiconductor package together by scanning a laser beam along adjacent edges of the members. The compositions of the members which are fused together include ceramic, glass and metal. The method enables the formation of a hermetic seal at a relatively low temperature thereby greatly reducing the thermal stress on the semiconductor chip with resulting improvement in yields.
Inventors
- 👤 Safidul Islam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:01
CPC Classifications
H; H10; H10W; H10W95/00; H10W76/00; H10W76/10; H10W76/12; H10W76/15; H10W76/157; H10W70/00; H10W70/60; H10W70/67; H10W70/68; H10W70/682; H10W72/00; H10W72/50; H10W72/531; H10W72/536; H10W72/5363; H10W72/851; H10W72/874; H10W72/884; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
134 words
A method of hermetically sealing a semiconductor chip within a package comprising: providing a first ceramic member having a plurality of conductive paths hermetically sealed therein; providing a plurality of electrically conductive leads for making external connections to the conductive paths; bonding a semiconductor chip to a surface of the first ceramic member; forming electrical connections between regions of the semiconductor chip and the conductive paths; providing a second ceramic member in abutting relationship with portions of the first ceramic member so as to define a compartment therebetween in which the semiconductor chip resides; and exposing adjacent edges of the first and second ceramic members to a laser beam for a sufficient duration to fuse the adjacent edges together throughout a closed loop so as to hermetically seal the compartment from the surrounding atmosphere.
Claim 2
Independent Claim
134 words
A method of hermetically sealing a semiconductor chip within a package comprising: providing a first ceramic member having a plurality of conductive paths hermetically sealed therein; providing a plurality of electrically conductive leads for making external connections to the conductive paths; bonding a semiconductor chip to a surface of the first ceramic member; forming electrical connections between regions of the semiconductor chip and the conductive paths; providing a second ceramic member in abutting relationship with portions of the first ceramic member so as to define a compartment therebetween in which the semiconductor chip resides; and exposing adjacent edges of the first and second ceramic members to a laser beam for a sufficient duration to fuse the adjacent edges together throughout a closed loop so as to hermetically seal the compartment from the surrounding atmosphere.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein the first and second ceramic members comprise similar compositions of aluminum oxide and glass.
Claim 4
Dependent Claim
30 words
The method of claim 2 wherein the first and second ceramic members each comprise from about 70% to about 80% aluminum oxide and from about 20% to about 30% glass.
Claim 5
Dependent Claim
24 words
The method of claim 1 wherein the ceramic members are maintained at a temperature of about 200° C. during exposure to the laser beam.
References Cited (Backward Citations)
US4291815A
Cited
US4291815B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-29 | 1987-02-28 | 1987-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-29 | 1991-02-28 | 1991-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-29 | 1995-02-28 | 1995-08-30 | $7700.00 | Window Closed / Lapsed |