US5384155A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silver spot/palladium plate lead frame finish
Assignee: Texas Instruments Inc
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Filing: 1992-06-04
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Granted: 1995-01-24
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Expires: 2012-06-04
Abstract
Abstract The invention is to a method of spot plating parts of a plated semiconductor lead frame. The entire lead frame is first plated. Then parts of the lead frame, internal to the subsequent encapsulating package, are spot plated prior to encapsulating the semiconductor device. A spot of silver is plated in the mount and/or bond area of the lead frame.
Inventors
- 👤 Donald C. Abbott
- 👤 Robert M. Fritzsche
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:47
CPC Classifications
C; C23; C23C; C23C28/00; C23C28/02; C23C28/023; H; H10; H10W; H10W70/00; H10W70/40; H10W70/456; H10W70/457; H10W72/00; H10W72/071; H10W72/075; H10W72/50; H10W72/551; H10W72/552; H10W72/5522; H10W72/59; H10W72/90; H10W72/951; H10W72/952; H10W90/00; H10W90/701; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
60 words
A method for spot plating the parts of the lead frame internal to the plastic package prior to encapsulating a semiconductor device, comprising the steps of: plating the entire lead frame with a first metal; and spot plating selected portions of the lead frame, which portions are within the plastic package after encapsulation, over said first plated metal, with silver.
Claim 2
Independent Claim
60 words
A method for spot plating the parts of the lead frame internal to the plastic package prior to encapsulating a semiconductor device, comprising the steps of: plating the entire lead frame with a first metal; and spot plating selected portions of the lead frame, which portions are within the plastic package after encapsulation, over said first plated metal, with silver.
Claim 3
Dependent Claim
26 words
The method according to claim 1, including the step of plating the selected portions of the lead frame with copper prior to spot plating with silver.
Claim 4
Dependent Claim
17 words
The method according to claim 1, wherein the lead frame is plated with an alloy of palladium.
Claim 5
Dependent Claim
20 words
The method according to claim 3, wherein the first metal is selected from the group consisting of palladium and palladium-nickel.
Claim 6
Dependent Claim
25 words
The method according to claim 1, wherein the ends of the lead frame leads to be attached to a semiconductor device are plated with silver.
Claim 7
Independent Claim
56 words
A method for spot plating the parts of the lead frame internal to the plastic package prior to encapsulating a semiconductor device, comprising the steps of: plating the entire lead frame with palladium; and spot plating selected portions of the palladium plated lead frame leads, which portions are within the plastic package after encapsulation, with silver.
Claim 8
Independent Claim
56 words
A method for spot plating the parts of the lead frame internal to the plastic package prior to encapsulating a semiconductor device, comprising the steps of: plating the entire lead frame with palladium; and spot plating selected portions of the palladium plated lead frame leads, which portions are within the plastic package after encapsulation, with silver.
Claim 9
Dependent Claim
28 words
The method according to claim 6, including the step of spot plating the selected portions of the lead frame leads with copper prior to the plating with silver.
Claim 10
Dependent Claim
22 words
The method according to claim 6, wherein the lead frame is plated with a palladium alloy prior to spot plating with silver.
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) | 1998-01-23 | 1998-07-25 | 1999-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-01-23 | 2002-07-25 | 2003-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-01-23 | 2006-07-25 | 2007-01-24 | $7700.00 | Window Closed / Lapsed |