US5428889A
Expired / Lapsed
US
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Method for manufacturing composite lead frame
Assignee: Hitachi Cable Ltd
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Filing: 1992-12-30
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Granted: 1995-07-04
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Expires: 2012-12-30
Abstract
Abstract An outer lead of a metal lead frame is connected to an inner lead of a flexible lead-patterned substrate via a Au-Sn alloy layer. The Au-Sn alloy layer contains Au of 10 to 40 weight %. An inner lead of a metal lead frame is connected to a patterned lead of a flexible lead-patterned substrate by a heating tool. The inner lead is coated on bottom and side surfaces of its tip portion. The bottom surface faces the patterned lead.
Inventors
- 👤 Mamoru Mita
- 👤 Tomio Murakami
- 👤 Shoji Takagi
- 👤 Hiroki Tanaka
- 👤 Kenji Yamaguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:59
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/456; H10W70/457; H10W70/421; H10W70/464; H10W70/468; H10W72/00; H10W72/071; H10W72/075; H10W72/07551; H10W72/07554; H10W72/50; H10W72/541; H10W72/5449; H10W72/547; H10W72/551; H10W72/552; H10W72/90; H10W72/951; H10W72/952; H10W90/00; H10W90/701; H10W90/751; H10W90/754; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49121
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
124 words
In a method for manufacturing a composite lead frame by joining an outer lead and an inner lead with a Au--Sn eutectic alloy, wherein the outer lead is of a metal frame and the inner lead is of a conductive lead pattern on an insulating film, the method comprising the steps of: providing a Sn-plating layer on a joining surface of one of said outer and inner leads; providing a Au-plating layer on a joining surface of a remaining one of said outer and inner leads; and applying heat and pressure to joining surfaces of said outer and inner leads in contact with each other to be joined with said Au--Sn eutectic alloy, said Au--Sn alloy containing 10 to 40 weight % of Au.
Claim 2
Dependent Claim
124 words
In a method for manufacturing a composite lead frame by joining an outer lead and an inner lead with a Au--Sn eutectic alloy, wherein the outer lead is of a metal frame and the inner lead is of a conductive lead pattern on an insulating film, the method comprising the steps of: providing a Sn-plating layer on a joining surface of one of said outer and inner leads; providing a Au-plating layer on a joining surface of a remaining one of said outer and inner leads; and applying heat and pressure to joining surfaces of said outer and inner leads in contact with each other to be joined with said Au--Sn eutectic alloy, said Au--Sn alloy containing 10 to 40 weight % of Au.
Claim 3
Dependent Claim
125 words
A method for manufacturing a composite lead frame according to claim 1, wherein said Sn-plating layer is provided on a bottom surface and a side surface of a tip portion of said inner lead, said an outer lead being supported by a frame member of the metal frame; and further comprising positioning said tip portion of said inner lead on a patterned lead of a flexible lead-patterned substrate, said bottom surface facing said patterned lead of said flexible lead-patterned substrate, and said lead-patterned substrate comprising said insulation film and a plurality of patterned leads including said patterned lead provided on said insulation film; and applying said heat and pressure across said tip portion of said inner lead and said patterned lead by a heating tool.
Claim 4
Dependent Claim
42 words
A method for manufacturing a composite lead frame, according to claim 2, wherein: said step of providing said Sn-plating layer includes providing said Sn-plating layer on said side surface excluding a limited portion adjacent to a top surface of said inner lead.
Claim 5
Dependent Claim
50 words
A method for manufacturing a composite lead frame, according to claim 2, further comprising the step of: providing a plating layer on said patterned lead, said plating layer comprising a first layer of Ni provided on said patterned lead, and a second layer of Au provided on said first layer.
Claim 6
Dependent Claim
115 words
In a method for manufacturing a composite lead frame by joining an outer lead and an inner lead with a Au--Sn eutectic alloy, wherein the outer lead is of a metal lead frame and the inner lead is of a conductive lead pattern on an insulating film, the method comprising the steps of: providing a Sn-plating layer on a joining surface of said outer lead; providing a Au-plating layer on a joining surface of said inner lead; and applying heat and pressure to joining surfaces of said outer and inner leads in contact with each other to be joined with said Au--Sn eutectic alloy, said Au--Sn alloy containing 10 to 40 weight % of Au.
Claim 7
Dependent Claim
115 words
In a method for manufacturing a composite lead frame by joining an outer lead and an inner lead with a Au--Sn eutectic alloy, wherein the outer lead is of a metal lead frame and the inner lead is of a conductive lead pattern on an insulating film, the method comprising the steps of: providing a Sn-plating layer on a joining surface of said outer lead; providing a Au-plating layer on a joining surface of said inner lead; and applying heat and pressure to joining surfaces of said outer and inner leads in contact with each other to be joined with said Au--Sn eutectic alloy, said Au--Sn alloy containing 10 to 40 weight % of Au.
Claim 8
Dependent Claim
124 words
A method for manufacturing a composite lead frame according to claim 5, wherein said Sn-plating layer is provided on a bottom surface and a side surface of a tip portion of said inner lead, said outer lead being supported by a frame member of the metal frame; and further comprising positioning said tip portion of said inner lead on a patterned lead of a flexible lead-patterned substrate, said bottom surface facing said patterned lead of said flexible lead-patterned substrate, and said lead-patterned substrate comprising said insulation film and a plurality of patterned leads including said patterned lead provided on said insulation film; and applying said heat and pressure across said tip portion of said inner lead and said patterned lead by a heating tool.
Claim 9
Dependent Claim
42 words
A method for manufacturing a composite lead frame, according to claim 6, wherein: said step of providing said Sn-plating layer includes providing said Sn-plating layer on said side surface excluding a limited portion adjacent to a top surface of said inner lead.
Claim 10
Dependent Claim
50 words
A method for manufacturing a composite lead frame, according to claim 6, further comprising the step of: providing a plating layer on said patterned lead, said plating layer comprising a first layer of Ni provided on said patterned lead, and a second layer of Au provided on said first layer.
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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) | 1998-07-03 | 1999-01-02 | 1999-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-07-03 | 2003-01-02 | 2003-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-07-03 | 2007-01-02 | 2007-07-04 | $7700.00 | Window Closed / Lapsed |