US5256598A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shrink accommodating lead frame
Assignee: Micron Technology Inc
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Filing: 1992-04-15
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Granted: 1993-10-26
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Expires: 2012-04-15
Abstract
Abstract A lead frame design which can be used with a number of different die sizes is described. To customize the lead frame, a punch excises an amount of lead finger material to form a void between the lead fingers for receiving a die. The amount of material removed is greater for larger sized die. A material, such as an adhesive tape, attaches the die to the lead frame. The bond pads on the die are then wire bonded to the lead fingers. The adhesive tape also locks the lead fingers into place, thereby preventing movement which could detach the bond wires from the die or lead frame.
Inventors
- 👤 Warren M. Farnworth
- 👤 Alan G. Wood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:39
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/411; H10W70/415; H10W72/00; H10W72/01; H10W72/0198; H10W72/50; H10W72/541; H10W72/5449; H10W72/551; H10W72/552; H10W72/5522; H10W72/851; H10W72/853; H10W72/865; H10W72/874; H10W72/884; H10W72/90; H10W72/931; H10W72/932; H10W90/00; H10W90/701; H10W90/731; H10W90/736; H10W90/751; H10W90/756; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49121
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
94 words
A method of forming a semiconductor assembly, comprising the steps of: a) selecting a semiconductor die of a specific size for assembly; b) excising a portion of lead fingers from a lead frame to establish an inset of the lead fingers and to produce a paddleless lead frame, whereby the established inset of the lead fingers conforms to external dimensions of the selected die such that the selected die may be located within the inset, the amount of lead finger material excised depending on the size of a semiconductor die to be attached thereto.
Claim 2
Independent Claim
94 words
A method of forming a semiconductor assembly, comprising the steps of: a) selecting a semiconductor die of a specific size for assembly; b) excising a portion of lead fingers from a lead frame to establish an inset of the lead fingers and to produce a paddleless lead frame, whereby the established inset of the lead fingers conforms to external dimensions of the selected die such that the selected die may be located within the inset, the amount of lead finger material excised depending on the size of a semiconductor die to be attached thereto.
Claim 3
Dependent Claim
41 words
The method of forming a semiconductor assembly according to claim 1, further comprising the steps of: a) attaching a carrier material to said lead fingers, thereby sufficiently immobilizing said lead fingers; and b) attaching said semiconductor die to said carrier material.
Claim 4
Dependent Claim
27 words
The method of forming a semiconductor assembly according to claim 2, further comprising the step of electrically coupling bond pads on said die and said lead fingers.
Claim 5
Dependent Claim
27 words
The method of forming a semiconductor assembly according to claim 3, further comprising the step of encapsulating said lead fingers and said die with an encapsulation material.
Claim 6
Dependent Claim
25 words
The method of forming a semiconductor assembly according to claim 3 wherein said bond pads and said lead fingers are coupled with a bond wire.
Claim 7
Dependent Claim
25 words
The method of forming a semiconductor assembly according to claim 5 wherein said carrier material has a void therein, and said bond wires pass therethrough.
Claim 8
Independent Claim
122 words
A method of forming a semiconductor assembly, comprising the steps of: a) selecting a semiconductor die of a specific size for assembly; b) excising a portion of lead fingers from a lead frame with a punch to establish an inset of the lead fingers and to produce a paddleless lead frame, whereby the established inset of the lead fingers conforms to external dimensions of the selected die such that the selected die may be located within the inset, the amount of lead finger material excised depending on the size of a semiconductor die to be attached thereto; c) attaching a carrier material to said lead fingers, thereby sufficiently immobilizing said lead fingers; and d) attaching said semiconductor die to said carrier material.
Claim 9
Independent Claim
122 words
A method of forming a semiconductor assembly, comprising the steps of: a) selecting a semiconductor die of a specific size for assembly; b) excising a portion of lead fingers from a lead frame with a punch to establish an inset of the lead fingers and to produce a paddleless lead frame, whereby the established inset of the lead fingers conforms to external dimensions of the selected die such that the selected die may be located within the inset, the amount of lead finger material excised depending on the size of a semiconductor die to be attached thereto; c) attaching a carrier material to said lead fingers, thereby sufficiently immobilizing said lead fingers; and d) attaching said semiconductor die to said carrier material.
Claim 10
Dependent Claim
27 words
The method of forming a semiconductor assembly according to claim 7, further comprising the step of electrically coupling bond pads on said die and said lead fingers.
Claim 11
Dependent Claim
27 words
The method of forming a semiconductor assembly according to claim 8, further comprising the step of encapsulating said lead fingers and said die with an encapsulation material.
Claim 12
Dependent Claim
25 words
The method of forming a semiconductor assembly according to claim 8, wherein said bond pads and said lead fingers are coupled with a bond wire.
Claim 13
Dependent Claim
22 words
The method of forming a semiconductor assembly according to claim 10 wherein carrier material void therein and said bond wires pass therethrough.
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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) | 1996-10-25 | 1997-04-26 | 1997-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-10-25 | 2001-04-26 | 2001-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-10-25 | 2005-04-26 | 2005-10-26 | $7700.00 | Window Closed / Lapsed |