Patent US5672547A successfully refreshed from Google Patents.
US5672547A
Expired / Lapsed
US
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Method for bonding a heat sink to a die paddle
Assignee: Transpacific IP Ltd
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Filing: 1996-01-31
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Granted: 1997-09-30
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Expires: 2016-01-31
Abstract
Abstract A method of bonding an integrated circuit die to a heat sink by first providing a lead frame that has a die paddle portion having a top surface, a bottom surface, and at least one aperture therethrough, positioning a heat sink abutting the bottom surface of the die paddle portion, and then pressing an integrated circuit die against the top surface of the die paddle portion with an adhesive material sandwiched therein between such that the adhesive flows through at least one aperture in the die paddle portion to bond the integrated circuit die and the heat sink together.
Inventors
- 👤 Jian Dih Jeng
- 👤 Hsing Seng Wang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:14
CPC Classifications
H; H10; H10W; H10W40/00; H10W40/70; H10W40/77; H10W40/778; H10W70/00; H10W70/40; H10W70/411; H10W72/00; H10W72/071; H10W72/073; H10W72/07331; H10W72/07337; H10W72/07351; H10W72/07353; H10W72/30; H10W72/331; H10W72/334; H10W72/351; H10W72/353; H10W72/354; H10W72/851; H10W72/874; H10W72/884; H10W72/90; H10W72/931; H10W74/00; H10W90/00; H10W90/701; H10W90/731; H10W90/736; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
135 words
A method of bonding an integrated circuit die to a heat sink, comprising the steps of: providing a lead frame having a die paddle portion, said die paddle portion having a top surface, a bottom surface, and at least one aperture therethrough, positioning a heat sink abutting said bottom surface of said die paddle portion wherein said heat sink has recessed areas in the surface facing said die paddle portion at locations corresponding to the locations of said at least one aperture when said heat sink and said die paddle portion are bonded together, and pressing an integrated circuit die against the top surface of said die paddle portion with an adhesive sandwiched therein between such that the adhesive flows through said at least one aperture of said die paddle adhering to said heat sink.
Claim 2
Independent Claim
135 words
A method of bonding an integrated circuit die to a heat sink, comprising the steps of: providing a lead frame having a die paddle portion, said die paddle portion having a top surface, a bottom surface, and at least one aperture therethrough, positioning a heat sink abutting said bottom surface of said die paddle portion wherein said heat sink has recessed areas in the surface facing said die paddle portion at locations corresponding to the locations of said at least one aperture when said heat sink and said die paddle portion are bonded together, and pressing an integrated circuit die against the top surface of said die paddle portion with an adhesive sandwiched therein between such that the adhesive flows through said at least one aperture of said die paddle adhering to said heat sink.
Claim 3
Dependent Claim
17 words
A method according to claim 1, wherein said heat sink being made of a heat conducting material.
Claim 4
Dependent Claim
36 words
A method according to claim 1, wherein said heat sink being made of a material selected from the group consisting of Cu, Cu alloys, Al, Al alloys and any other high thermal conductivity metals and alloys.
Claim 5
Dependent Claim
26 words
A method according to claim 1, wherein said heat sink after a subsequent plastic encapsulation process has a surface exposed to ambient to facilitate heat dissipation.
Claim 6
Dependent Claim
13 words
A method according to claim 1, wherein said adhesive is a dielectric material.
Claim 7
Dependent Claim
13 words
A method according to claim 1, wherein said adhesive is a polymeric material.
Claim 8
Dependent Claim
18 words
A method according to claim 1, wherein said adhesive is a dielectric material filled with a metal powder.
Claim 9
Dependent Claim
25 words
A method according to claim 1, wherein said integrated circuit die and said die paddle portion are pressed together in a pair of metal platen.
Claim 10
Independent Claim
176 words
A method of fabricating a plastic molded package of an electronic device, comprising the steps of: positioning a lead frame having a die paddle portion in a mold cavity, said die paddle portion having a top surface and a bottom surface and at least one aperture therethrough, positioning a non-adhesive backed heat sink abutting the bottom surface of said die paddle portion wherein said heat sink has recessed areas in the surface facing said paddle portion at locations corresponding to the locations of said at least one aperture when said heat sink and said paddle portion are bonded together, pressing an integrated circuit die against the top surface of said die paddle with an adhesive therein between such that the adhesive is pushed through the apertures of said paddle portion to contact said heat sink, wire bonding said integrated circuit die to said lead frame, and injecting a plastic material into said mold cavity to encapsulate said lead frame, said integrated circuit die, said die paddle, and said heat sink together forming a plastic molded package.
Claim 11
Independent Claim
176 words
A method of fabricating a plastic molded package of an electronic device, comprising the steps of: positioning a lead frame having a die paddle portion in a mold cavity, said die paddle portion having a top surface and a bottom surface and at least one aperture therethrough, positioning a non-adhesive backed heat sink abutting the bottom surface of said die paddle portion wherein said heat sink has recessed areas in the surface facing said paddle portion at locations corresponding to the locations of said at least one aperture when said heat sink and said paddle portion are bonded together, pressing an integrated circuit die against the top surface of said die paddle with an adhesive therein between such that the adhesive is pushed through the apertures of said paddle portion to contact said heat sink, wire bonding said integrated circuit die to said lead frame, and injecting a plastic material into said mold cavity to encapsulate said lead frame, said integrated circuit die, said die paddle, and said heat sink together forming a plastic molded package.
Claim 12
Dependent Claim
16 words
A method according to claim 9, wherein said heat sink being made of a heat conducting.
Claim 13
Dependent Claim
36 words
A method according to claim 9, wherein said heat sink being made of a material selected from the group consisting of Cu, Cu alloys, Al, Al alloys and any other high thermal conductivity metals and alloys.
Claim 14
Dependent Claim
24 words
A method according to claim 9, wherein said heat sink encapsulated in said plastic molded package has at least one surface exposed to ambient.
Claim 15
Dependent Claim
13 words
A method according to claim 9, wherein said adhesive is a dielectric material.
Claim 16
Dependent Claim
18 words
A method according to claim 9, wherein said adhesive is a dielectric material filled with a metal powder.
Claim 17
Dependent Claim
25 words
A method according to claim 9, wherein said integrated circuit die and said die paddle portion are pressed together in a pair of metal platen.
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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) | 2000-09-29 | 2001-03-31 | 2001-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-09-29 | 2005-03-31 | 2005-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-09-29 | 2009-03-31 | 2009-09-30 | $7700.00 | Window Closed / Lapsed |