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US4640723A Expired / Lapsed US ⏱️ 0.0 years remaining

Lead frame and method for manufacturing the same

Assignee: Toshiba Corp
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Filing: 1983-12-20
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Granted: 1987-02-03
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Expires: 2003-12-20
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Abstract

Abstract A lead frame consists of a copper alloy containing 0.1 to 1% by weight of chromium and 0.001 to 0.5% by weight of zirconium and having a precipitate with a grain size of 0.5 to 50 mu m distributed therein at a rate of 1,000 to 10,000 grains/mm2. The lead frame is manufactured by casting a copper alloy containing 0.1 to 1% by weight of chromium and 0.001 to 0.5% by weight of zirconium by continuous casting, and performing rolling, a solution treatment, a cold working, and an age-hardening. The lead frame has an excellent bonding performance with an Au wire, hardness and bending strength, and is inexpensive.

Inventors

  • 👤 Shinzo Sugai
  • 👤 Shigemi Yamane
  • 👤 Takashi Kuze

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 18:07
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/456; C; C22; C22C; C22C9/00; C22F; C22F1/00; C22F1/08; H10W72/00; H10W72/01; H10W72/0198; H10W72/50; H10W72/531; H10W72/536; H10W72/5363; H10W72/551; H10W72/552; H10W72/5522; H10W72/851; H10W72/874; H10W72/884; H10W74/00; H10W90/00; H10W90/701; H10W90/731; H10W90/736; H10W90/751; H10W90/756

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 48 words
A lead frame comprising a copper alloy containing 0.1 to 1% by weight of chromium and 0.001 to 0.5% by weight of zirconium and having a precipitate with a grain size from 0.5 to 50 μm distributed therein at a rate of 1,000 to 10,000 grains/mm 2 .
Claim 2
Dependent Claim 48 words
A lead frame comprising a copper alloy containing 0.1 to 1% by weight of chromium and 0.001 to 0.5% by weight of zirconium and having a precipitate with a grain size from 0.5 to 50 μm distributed therein at a rate of 1,000 to 10,000 grains/mm 2 .
Claim 3
Dependent Claim 45 words
A lead frame according to claim 1, wherein the copper alloy further contains not more than 1% by weight of at least one member selected from the group consisting of magnesium, silicon, tin, nickel, iron, zinc, manganese, phosphorus, boron, silver, beryllium, cobalt, titanium and yttrium.
Claim 4
Dependent Claim 116 words
A lead frame comprising a copper alloy containing 0.1 to 1% by weight of chromium and 0.001 to 0.5% by weight of zirconium and having a precipitate with a grain size from 0.5 to 50 μm distributed therein at a rate of 1,000 to 10,000 grains/mm 2 , wherein the copper alloy further contains not more than 1% by weight of at least one member selected from the group consisting of magnesium, silicon, tin, nickel, iron, zinc, manganese, phosphorus, boron, silver, beryllium, cobalt, titanium and yttrium, said copper alloy being formed by the sequential steps of continuously casting the alloy, rolling the cast alloy, solution treating the alloy, cold working the alloy, and age-hardening the alloy.
Claim 5
Dependent Claim 116 words
A lead frame comprising a copper alloy containing 0.1 to 1% by weight of chromium and 0.001 to 0.5% by weight of zirconium and having a precipitate with a grain size from 0.5 to 50 μm distributed therein at a rate of 1,000 to 10,000 grains/mm 2 , wherein the copper alloy further contains not more than 1% by weight of at least one member selected from the group consisting of magnesium, silicon, tin, nickel, iron, zinc, manganese, phosphorus, boron, silver, beryllium, cobalt, titanium and yttrium, said copper alloy being formed by the sequential steps of continuously casting the alloy, rolling the cast alloy, solution treating the alloy, cold working the alloy, and age-hardening the alloy.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-02-02 1990-08-04 1991-02-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-02-02 1994-08-04 1995-02-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-02-02 1998-08-04 1999-02-03 $7700.00 Window Closed / Lapsed

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