US5239131A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic package having controlled epoxy flow
Assignee: Advanced Technology Interconnect Inc
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Filing: 1992-07-13
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Granted: 1993-08-24
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Expires: 2012-07-13
Abstract
Abstract There is provided an electronic package assembly having a die attach paddle bonded to the package base by a compliant adhesive. A recessed channel formed in the base is partially overlapped by the die attach paddle. During package sealing, excess adhesive accumulates in the recessed channel, eliminating bridging of the adhesive to the leadframe.
Inventors
- 👤 Paul R. Hoffman
- 👤 Linda E. Strauman
- 👤 Dexin Liang
- 👤 Sonny S. Pareno
- 👤 German J. Ramirez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:09
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/01; H10W70/04; H10W70/047; H10W72/00; H10W72/30; H10W72/50; H10W72/851; H10W72/01; H10W72/013; H10W72/01308; H10W72/071; H10W72/073; H10W72/07311; H10W72/381; H10W72/551; H10W72/552; H10W72/5522; H10W72/5524; H10W72/5525; H10W72/874; H10W72/884; H10W90/00; H10W90/701; H10W90/731; H10W90/736; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
69 words
An electronic package assembly, comprising: a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region; a base containing a channel; and a first polymer adhesive bonding said base to said leadframe and a compliant second polymer adhesive bonding said base to said die attach paddle with said channel disposed within said central region.
Claim 2
Dependent Claim
69 words
An electronic package assembly, comprising: a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region; a base containing a channel; and a first polymer adhesive bonding said base to said leadframe and a compliant second polymer adhesive bonding said base to said die attach paddle with said channel disposed within said central region.
Claim 3
Dependent Claim
18 words
The electronic package assembly of claim 1 wherein said channel is spaced apart from said inner lead ends.
Claim 4
Dependent Claim
27 words
The electronic package assembly of claim 2 wherein the space between said channel and said inner lead ends is from about 0.13 millimeters to about 0.4 millimeters.
Claim 5
Dependent Claim
27 words
The electronic package assembly of claim 3 wherein the space between said channel and said inner lead ends is from about 0.20 millimeters to about 0.3 millimeters.
Claim 6
Dependent Claim
69 words
An electronic package assembly, comprising: a base containing a recessed channel; a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region and at least partially overlapping said channel; and a first polymer adhesive bonding said base to said leadframe and a compliant second polymer adhesive bonding said base to said die attach paddle.
Claim 7
Dependent Claim
69 words
An electronic package assembly, comprising: a base containing a recessed channel; a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region and at least partially overlapping said channel; and a first polymer adhesive bonding said base to said leadframe and a compliant second polymer adhesive bonding said base to said die attach paddle.
Claim 8
Dependent Claim
23 words
The electronic package assembly of claim 5 wherein up to about 25 area percent of said die attach paddle overlaps said recessed channel.
Claim 9
Dependent Claim
25 words
The electronic package assembly of claim 6 wherein from about 10 to about 20 area percent of said die attach paddle overlaps said recessed channel.
Claim 10
Dependent Claim
20 words
The electronic package assembly of claim 6 wherein the depth of said recessed channel is up to about 1 millimeter.
Claim 11
Dependent Claim
22 words
The electronic package assembly of claim 8 wherein said recessed channel is stamped to a depth of up to about 0.25 millimeters.
Claim 12
Dependent Claim
23 words
The electronic package assembly of claim 9 wherein the depth of said recessed channel is from about 0.075 millimeters to about 0.175 millimeters.
Claim 13
Dependent Claim
119 words
An adhesively sealed metal electronic package, comprising: a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region; a metallic base component bonded to said leadframe with a first polymer adhesive and to said die attach paddle with a compliant second polymer adhesive, said base component having a recessed channel disposed in said central region such that the outer perimeter of said recessed channel is spaced from said inner lead ends and the inner perimeter of said recessed channel is overlapped by said die attach paddle; and a cover bonded to said metallic base by said first polymer adhesive with said leadframe disposed therebetween.
Claim 14
Dependent Claim
119 words
An adhesively sealed metal electronic package, comprising: a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region; a metallic base component bonded to said leadframe with a first polymer adhesive and to said die attach paddle with a compliant second polymer adhesive, said base component having a recessed channel disposed in said central region such that the outer perimeter of said recessed channel is spaced from said inner lead ends and the inner perimeter of said recessed channel is overlapped by said die attach paddle; and a cover bonded to said metallic base by said first polymer adhesive with said leadframe disposed therebetween.
Claim 15
Dependent Claim
144 words
A metal electronic package, comprising: a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region; an aluminum alloy base component bonded to said leadframe with a first polymer adhesive and to said die attach paddle with a compliant second polymer adhesive, said aluminum alloy base component having a recessed channel disposed in said central region such that the outer perimeter of said recessed channel is spaced from said inner lead ends and the inner perimeter of said recessed channel is overlapped by said die attach paddle; and an aluminum alloy cover bonded to said aluminum alloy base by said first polymer adhesive with said leadframe disposed therebetween, wherein both said aluminum alloy base component and said aluminum alloy cover are at least partially coated with an anodization layer.
Claim 16
Dependent Claim
144 words
A metal electronic package, comprising: a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region; an aluminum alloy base component bonded to said leadframe with a first polymer adhesive and to said die attach paddle with a compliant second polymer adhesive, said aluminum alloy base component having a recessed channel disposed in said central region such that the outer perimeter of said recessed channel is spaced from said inner lead ends and the inner perimeter of said recessed channel is overlapped by said die attach paddle; and an aluminum alloy cover bonded to said aluminum alloy base by said first polymer adhesive with said leadframe disposed therebetween, wherein both said aluminum alloy base component and said aluminum alloy cover are at least partially coated with an anodization layer.
Claim 17
Dependent Claim
23 words
The metal electronic package of claim 12 wherein the depth of said recessed channel is from about 0.075 millimeters to about 0.175 millimeters.
Claim 18
Dependent Claim
32 words
The metal electronic package of claim 13 wherein the space between said outer perimeter of said recessed channel and said inner lead ends is from about 0.13 millimeters to about 0.40 millimeters.
Claim 19
Dependent Claim
25 words
The metal electronic package of claim 14 wherein the area percent of said die attach paddle overlapping said recessed channel is up to about 25%.
Claim 20
Dependent Claim
27 words
The metal electronic package of claim 15 wherein the area percent of said die attach paddle overlapping said recessed channel is from about 10% to about 20%.
Claim 21
Dependent Claim
127 words
An adhesively sealed metal electronic package, comprising: a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region; a metallic base component adhesively bonded to said leadframe and to said die attach paddle with a polymer adhesive, said base component having a recessed channel disposed in said central region such that the outer perimeter of said recessed channel is spaced from said inner lead ends and the inner perimeter of said recessed channel is overlapped by said die attach paddle; a window frame having first and second sides, said first side bonded to said base with said leadframe disposed therebetween; and a cover bonded to said second side of said window frame.
Claim 22
Dependent Claim
127 words
An adhesively sealed metal electronic package, comprising: a leadframe having a plurality of leads, the inner lead ends of which define a central region; a die attach paddle located within said central region; a metallic base component adhesively bonded to said leadframe and to said die attach paddle with a polymer adhesive, said base component having a recessed channel disposed in said central region such that the outer perimeter of said recessed channel is spaced from said inner lead ends and the inner perimeter of said recessed channel is overlapped by said die attach paddle; a window frame having first and second sides, said first side bonded to said base with said leadframe disposed therebetween; and a cover bonded to said second side of said window frame.
Claim 23
Dependent Claim
20 words
The metal electronic package of claim 17 wherein the depth of said recessed channel is up to about 0.25 millimeters.
Claim 24
Dependent Claim
28 words
The metal electronic package of claim 18 wherein the space between said recessed channel and said inner lead ends is from about 0.13 millimeters to about 0.40 millimeters.
Claim 25
Dependent Claim
25 words
The metal electronic package of claim 19 wherein the area percent of said die attach paddle overlapping said recessed channel is less than about 25%.
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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) | 1996-08-23 | 1997-02-22 | 1997-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-23 | 2001-02-22 | 2001-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-23 | 2005-02-22 | 2005-08-24 | $7700.00 | Window Closed / Lapsed |