Patent US4924291A successfully refreshed from Google Patents.
US4924291A
Expired / Lapsed
US
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Flagless semiconductor package
Assignee: NXP USA Inc
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Filing: 1988-10-24
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Granted: 1990-05-08
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Expires: 2008-10-24
Abstract
Abstract A molded semiconductor package having a flagless leadframe wherein a semiconductor die is disposed in or above a die opening of a leadframe. This allows for thin, symmetrical packages and packages having a minimum number of material interfaces to be manufactured because no leadframe flags and minimal die bond material are employed. The present invention further includes guard rings to protect high stress areas of the semiconductor die from damage and heat spreaders to more effectively spread heat dissipated by the semiconductor die.
Inventors
- 👤 Israel A. Lesk
- 👤 George W. Hawkins
- 👤 Ronald E. Thomas
- 👤 William L. Hunter
- 👤 James J. Casto
- 👤 Michael B. McShane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:34
CPC Classifications
H; H10; H10W; H10W90/00; H10W90/811; H10W70/00; H10W70/40; H10W70/461; H10W40/00; H10W40/10; H10W40/70; H10W40/77; H10W40/778; H10W70/411; H10W70/417; H10W70/421; H10W74/00; H10W74/10; H10W74/111; H10W76/00; H10W76/40; H10W90/701; H10W90/731; H10W90/736
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
76 words
A molded semiconductor package having a flagless leadframe comprising: a semiconductor die having a first surface, a second surface, sides and corners; a flagless leadframe including leads and a die opening, said leadframe being physically bonded to said semiconductor die and further,, said leads of said leadframe being wire bonded to said semiconductor die in a selective manner; and an encapsulation disposed about said semiconductor die and said leadframe except for said leads which protrude therefrom.
Claim 2
Dependent Claim
76 words
A molded semiconductor package having a flagless leadframe comprising: a semiconductor die having a first surface, a second surface, sides and corners; a flagless leadframe including leads and a die opening, said leadframe being physically bonded to said semiconductor die and further,, said leads of said leadframe being wire bonded to said semiconductor die in a selective manner; and an encapsulation disposed about said semiconductor die and said leadframe except for said leads which protrude therefrom.
Claim 3
Dependent Claim
34 words
The molded semiconductor package of claim 1 wherein the die opening is larger than the semiconductor die disposed therein, the leadframe is essentially coplanar with said semiconductor die and said package is substantially symmetrical.
Claim 4
Dependent Claim
29 words
The molded semiconductor package of claim 2 wherein the leadframe is bonded to one or both of the sides and corners of the semiconductor die by an organic adhesive.
Claim 5
Dependent Claim
32 words
The molded semiconductor package of claim 2 further comprising a guard ring being disposed about the semiconductor die, said guard ring being a part of the leadframe or separate from said leadframe.
Claim 6
Dependent Claim
42 words
The molded semiconductor package of claim 4 wherein the guard ring is disposed between the leadframe and the semiconductor die and is bonded to at least one or both of the sides and corners of said semiconductor die by an organic adhesive.
Claim 7
Dependent Claim
34 words
The molded semiconductor package of claim 1 wherein the die opening is smaller than the semiconductor die and the second surface of said semiconductor die is bonded to the leadframe above said die opening.
Claim 8
Dependent Claim
28 words
The molded semiconductor package of claim 1 further comprising a thermally conductive heat spreader coupled to the second surface of the semiconductor die by an insulating adhesive material.
Claim 9
Dependent Claim
26 words
The molded semiconductor package of claim 7 wherein the thermally conductive heat spreader is coupled to the leads of the leadframe by an insulating adhesive material.
Claim 10
Dependent Claim
20 words
The molded semiconductor package of claim 7 wherein the thermally conductive heat spreader is not completely encapsulated by the encapsulation.
Claim 11
Dependent Claim
80 words
A substantially symmetrical molded semiconductor package having a flagless leadframe comprising: a semiconductor die having a first surface, a second surface, sides and corners; a flagless leadframe including leads and a die opening, said leadframe being disposed about and bonded to said semiconductor die, said leadframe further being essentially coplanar with and wire bonded to said semiconductor die in a selective manner; and an encapsulation disposed about said semiconductor die and said leadframe except for said leads which protrude therefrom.
Claim 12
Dependent Claim
80 words
A substantially symmetrical molded semiconductor package having a flagless leadframe comprising: a semiconductor die having a first surface, a second surface, sides and corners; a flagless leadframe including leads and a die opening, said leadframe being disposed about and bonded to said semiconductor die, said leadframe further being essentially coplanar with and wire bonded to said semiconductor die in a selective manner; and an encapsulation disposed about said semiconductor die and said leadframe except for said leads which protrude therefrom.
Claim 13
Dependent Claim
29 words
The molded semiconductor package of claim 10 wherein the leadframe is bonded to one or both of the sides and corners of the semiconductor die by an organic adhesive.
Claim 14
Dependent Claim
53 words
The molded semiconductor package of claim 10 further comprising a guard ring disposed between the leadframe and the semiconductor die, said guard ring being a part of the leadframe or separate from the leadframe and bonded to at least one of the sides or corners of said semiconductor die by an organic adhesive.
Claim 15
Dependent Claim
28 words
The molded semiconductor package of claim 10 further comprising a thermally conductive heat spreader coupled to the second surface of the semiconductor die by an insulating adhesive material.
Claim 16
Dependent Claim
26 words
The molded semiconductor package of claim 13 wherein the thermally conductive heat spreader is coupled to the leads of the leadframe by an insulating adhesive material.
Claim 17
Dependent Claim
20 words
The molded semiconductor package of claim 13 wherein the thermally conductive heat spreader is not completely encapsulated by the encapsulation.
Claim 18
Dependent Claim
88 words
A molded semiconductor package having a flagless leadframe comprising: a semiconductor die having a first surface, a second surface, sides and corners; a flagless leadframe including leads and a die opening, said die opening being smaller than said semiconductor die and said second surface of said semiconductor die being bonded to said leadframe above said opening said semiconductor die further being selectively wire bonded to said leads of said leadframe; and an encapsulation disposed about said semiconductor die and said leadframe except for said leads which protrude therefrom.
Claim 19
Dependent Claim
88 words
A molded semiconductor package having a flagless leadframe comprising: a semiconductor die having a first surface, a second surface, sides and corners; a flagless leadframe including leads and a die opening, said die opening being smaller than said semiconductor die and said second surface of said semiconductor die being bonded to said leadframe above said opening said semiconductor die further being selectively wire bonded to said leads of said leadframe; and an encapsulation disposed about said semiconductor die and said leadframe except for said leads which protrude therefrom.
Claim 20
Dependent Claim
28 words
The molded semiconductor package of claim 16 further comprising a thermally conductive heat spreader coupled to the second surface of the semiconductor die by an insulating adhesive material.
Claim 21
Dependent Claim
26 words
The molded semiconductor package of claim 17 wherein the thermally conductive heat spreader is coupled to the leads of the leadframe by an insulating adhesive material.
Claim 22
Dependent Claim
20 words
The molded semiconductor package of claim 17 wherein the thermally conductive heat spreader is not completely encapsulated by the encapsulation.
References Cited (Backward Citations)
US3902148A
Cited
US3716761A
Cited
US4578697A
Cited
US4466183A
Cited
US4489465A
Cited
US4595945A
Cited
US4612564A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-07 | 1993-11-06 | 1994-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-07 | 1997-11-06 | 1998-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-07 | 2001-11-06 | 2002-05-08 | $7700.00 | Window Closed / Lapsed |