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US5933708A
Expired / Lapsed
US
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Lead-on-chip semiconductor package and method for making the same
Assignee: Samsung Electronics Co Ltd
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Filing: 1997-04-17
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Granted: 1999-08-03
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Expires: 2017-04-17
Abstract
Abstract A method for bonding a semiconductor chip to a lead frame in a LOC type semiconductor package in which a plurality of inner leads are bonded to an active surface of the semiconductor chip. A semiconductor chip is prepared with a partially-cured polyimide layer on the active surface. One or more strips of polyimide tape is attached to the inner leads. The semiconductor chip is attached to the inner leads by making an intermediate pressure bond between the polyimide tape and the partially-cured polyimide coating layer on the active surface. The polyimide coating layer is then cured.
Inventors
- 👤 Sung Min Sim
- 👤 Young Hee Song
- 👤 Young Do Kweon
- 👤 Hai Jeong Sohn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:52
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/411; H10W70/415; H10W72/00; H10W72/071; H10W72/075; H10W72/30; H10W72/381; H10W72/50; H10W72/531; H10W72/536; H10W72/5363; H10W72/541; H10W72/5449; H10W72/551; H10W72/552; H10W72/5522; H10W72/59; H10W72/851; H10W72/853; H10W72/865; H10W72/90; H10W72/931; H10W72/932; H10W72/941; H10W72/944; H10W72/9445; H10W72/951; H10W74/00; H10W90/00; H10W90/701; H10W90/731; H10W90/734; H10W90/736; H10W90/751; H10W90/754; H10W90/756
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
88 words
A method for bonding a semiconductor chip to a lead frame in a lead-on-chip (LOC) type semiconductor package in which a plurality of inner leads are bonded to an active surface of the semiconductor chip, said method comprising: preparing a semiconductor chip with a partially-cured polyimide coating on the active surface of the chip; attaching one side of a polyimide film to the inner leads; pressing the other side of the polyimide film against the polyimide coating on the active surface of the chip; and curing the coating.
Claim 2
Independent Claim
88 words
A method for bonding a semiconductor chip to a lead frame in a lead-on-chip (LOC) type semiconductor package in which a plurality of inner leads are bonded to an active surface of the semiconductor chip, said method comprising: preparing a semiconductor chip with a partially-cured polyimide coating on the active surface of the chip; attaching one side of a polyimide film to the inner leads; pressing the other side of the polyimide film against the polyimide coating on the active surface of the chip; and curing the coating.
Claim 3
Dependent Claim
38 words
The method of claim 1 wherein preparing a semiconductor chip with a partially-cured polyimide coating comprises curing an uncured polyimide layer for 0.5 to 1 hour at a temperature in the range of 200° C. to 250° C.
Claim 4
Dependent Claim
29 words
The method of claim 1 wherein pressing the other side of the polyimide film against the polyimide coating comprises applying pressure of 2-4 Kgf/cm 2 to the inner leads.
Claim 5
Dependent Claim
35 words
The method of claim 3 wherein pressing the other side of the polyimide film against the polyimide coating comprises pressing a tool against the inner leads and wherein said method further comprises heating the tool.
Claim 6
Dependent Claim
25 words
The method of claim 4 wherein heating the tool comprises heating the tool to a temperature in the range of 380° C. to 420° C.
Claim 7
Dependent Claim
38 words
The method of claim 1 wherein the polyimide film has an adhesive layer on one side thereof and wherein attaching one side of the polyimide film to the inner leads comprises urging the adhesive layer against the leads.
Claim 8
Dependent Claim
46 words
The method of claim 1 wherein the polyimide film is partially-cured and wherein said method further comprises curing the polyimide film after attaching one side of the polyimide film to the inner leads and pressing the other side of the polyimide film against the polyimide coating.
Claim 9
Independent Claim
77 words
A method for bonding a semiconductor chip to a lead frame in a lead-on-chip (LOC) type semiconductor package in which a plurality of inner leads are bonded to an active surface of the semiconductor chip, said method comprising: preparing a partially-cured polyimide film; attaching one side of the polyimide film to the inner leads; pressing the other side of the polyimide film against a polyimide coating on the active surface of the chip; and curing the film.
Claim 10
Independent Claim
77 words
A method for bonding a semiconductor chip to a lead frame in a lead-on-chip (LOC) type semiconductor package in which a plurality of inner leads are bonded to an active surface of the semiconductor chip, said method comprising: preparing a partially-cured polyimide film; attaching one side of the polyimide film to the inner leads; pressing the other side of the polyimide film against a polyimide coating on the active surface of the chip; and curing the film.
Claim 11
Dependent Claim
34 words
The method of claim 8 wherein preparing a partially-cured polyimide film comprises curing an uncured polyimide layer for 0.5 to 1 hour at a temperature in the range of 200° C. to 250° C.
Claim 12
Dependent Claim
29 words
The method of claim 8 wherein pressing the other side of the polyimide film against the polyimide coating comprises applying pressure of 2-4 Kgf/cm 2 to the inner leads.
Claim 13
Dependent Claim
35 words
The method of claim 10 wherein pressing the other side of the polyimide film against the polyimide coating comprises pressing a tool against the inner leads and wherein said method further comprises heating the tool.
Claim 14
Dependent Claim
25 words
The method of claim 11 wherein heating the tool comprises heating the tool to a temperature in the range of 380° C. to 420° C.
Claim 15
Dependent Claim
38 words
The method of claim 8 wherein the polyimide film has an adhesive layer on one side thereof and wherein attaching one side of the polyimide film to the inner leads comprises urging the adhesive layer against the leads.
Claim 16
Dependent Claim
46 words
The method of claim 8 wherein the polyimide coating is partially-cured and wherein said method further comprises curing the polyimide coating after attaching one side of the polyimide film to the inner leads and pressing the other side of the polyimide film against the polyimide coating.
References Cited (Backward Citations)
US5286679A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2002-08-02 | 2003-02-01 | 2003-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-02 | 2007-02-01 | 2007-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-02 | 2011-02-01 | 2011-08-03 | $7700.00 | Window Closed / Lapsed |