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US5451813A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor device with lead frame having different thicknesses

Assignee: Rohm Co Ltd
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Filing: 1994-03-09
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Granted: 1995-09-19
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Expires: 2014-03-09
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Abstract

Abstract A semiconductor device includes a lead frame which has an island portion on which a semiconductor chip is mounted and which is coated with a sealing resin, inner lead portions which are connected to electrodes of the semiconductor chip and are coated with the sealing resin; and outer lead portions which are continuously extended from the inner lead portions and are not coated with the sealing resin. The island portion and inner lead portions are formed to be smaller in thickness than the outer lead portions by, for example, rolling a roller along a material for the lead frame.

Inventors

  • 👤 Shibata Kazutaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 07:57
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/01; H10W70/04; H10W70/048; H10W70/40; H10W70/421; H10W70/424

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 101 words
A semiconductor device comprising a lead frame, wherein said lead frame comprises an island portion and inner lead portions coated with a sealing resin; and outer lead portions which are integral with and continuously extend from corresponding inner lead portions and are not coated with said sealing resin, wherein said island portion and inner lead portions and outer lead portions are unitary segments of the same sheet of material and the island portion and inner lead portions are smaller in thickness than said outer lead portions and have a surface which is coplanar with a surface of the outer lead portions.
Claim 2
Dependent Claim 101 words
A semiconductor device comprising a lead frame, wherein said lead frame comprises an island portion and inner lead portions coated with a sealing resin; and outer lead portions which are integral with and continuously extend from corresponding inner lead portions and are not coated with said sealing resin, wherein said island portion and inner lead portions and outer lead portions are unitary segments of the same sheet of material and the island portion and inner lead portions are smaller in thickness than said outer lead portions and have a surface which is coplanar with a surface of the outer lead portions.
Claim 3
Dependent Claim 126 words
A semiconductor device comprising a lead frame, wherein said lead frame comprises an island portion on which a semiconductor chip is mounted and which is coated with a sealing resin, inner lead portions which are connected to electrodes of said semiconductor chip and are coated with said sealing resin; and outer lead portions which are integral with and continuously extend from corresponding inner lead portions and are not coated with said sealing resin, wherein said island portion and inner lead portions and outer lead portions are unitary segments of the same sheet of material and the island portion and inner lead portions are smaller in thickness than said outer lead portions and have a surface which is coplanar with a surface of the outer lead portions.
Claim 4
Dependent Claim 126 words
A semiconductor device comprising a lead frame, wherein said lead frame comprises an island portion on which a semiconductor chip is mounted and which is coated with a sealing resin, inner lead portions which are connected to electrodes of said semiconductor chip and are coated with said sealing resin; and outer lead portions which are integral with and continuously extend from corresponding inner lead portions and are not coated with said sealing resin, wherein said island portion and inner lead portions and outer lead portions are unitary segments of the same sheet of material and the island portion and inner lead portions are smaller in thickness than said outer lead portions and have a surface which is coplanar with a surface of the outer lead portions.

References Cited (Backward Citations)

US3947867A Cited
US4099200A Cited
JPS62177953A Cited
US4663651A Cited
US4717700A Cited
US4771330A Cited
US4872260A Cited
JPH0325252A Cited
US5014113A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-09-18 1999-03-20 1999-09-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-09-18 2003-03-20 2003-09-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-09-18 2007-03-20 2007-09-19 $7700.00 Window Closed / Lapsed

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