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US4707724A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor device and method of manufacturing thereof

Assignee: Hitachi Ltd
•
Filing: 1987-01-02
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Granted: 1987-11-17
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Expires: 2007-01-02
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Abstract

Abstract A nickel-alloy layer is formed on a lead frame made of a material which consists chiefly of copper as a base material, a pellet is then mounted, and a resin is applied thereto to form a package. Then, a copper layer or an alloy layer of copper and 0.05 to 0.2% by weight of zinc is formed on said nickel-containing alloy layer of the external lead portions. A solder layer is then formed on the copper layer or on the zinc-copper alloy layer that is formed on the external lead portions. With the thus formed semiconductor device, the resin exhibits increased adhesiveness relative to the tab and lead frame in the package. Therefore, peeling is prevented from occurring on the interface between the resin and the tab or lead frame. Further, no brittle intermetallic compound is formed by the heating in the metal layer such as the solder layer on the external lead portions. Accordingly, the metal layer is effectively prevented from peeling off.

Inventors

  • 👤 Akira Suzuki
  • 👤 Hideki Tanaka
  • 👤 Gen Murakami

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 18:50
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/40; H10W70/456; H10W70/457; H10W74/00; H10W74/10; H10W74/131; H10W76/00; H10W76/10; H10W76/17; H10W76/18; H10W90/00; H10W90/811; H10W72/00; H10W72/071; H10W72/075; H10W72/30; H10W72/321; H10W72/325; H10W72/351; H10W72/352; H10W72/353; H10W72/354; H10W72/50; H10W72/541; H10W72/5449; H10W72/551; H10W72/552; H10W72/851; H10W72/874; H10W72/884; H10W72/90; H10W72/951; H10W72/952; H10W90/701; H10W90/731; H10W90/736; H10W90/751; H10W90/756; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49121

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 157 words
In a semiconductor device comprising a pellet in which is formed a semiconductor integrated circuit with semiconductor elements as main elements, a plurality of leads that are electrically connected to a plurality of bonding pads of said pellet via fine metal wires, and a resinous sealing body which seals said pellet, said fine metal wires, and portions of said plurality of leads to which said fine metal wires are connected, the improvement wherein a base member of each of said leads is a copper alloy consisting chiefly of copper, an alloy layer consisting of nickel and tin or iron is formed on the whole surface of the base member of each of said leads, a metal plated layer consisting chiefly of copper is formed on portions of the leads exposed from said resinous sealing body, and a solder layer is formed on surfaces of the metal plated layer on the leads exposed from said resinous sealing body.
Claim 2
Dependent Claim 157 words
In a semiconductor device comprising a pellet in which is formed a semiconductor integrated circuit with semiconductor elements as main elements, a plurality of leads that are electrically connected to a plurality of bonding pads of said pellet via fine metal wires, and a resinous sealing body which seals said pellet, said fine metal wires, and portions of said plurality of leads to which said fine metal wires are connected, the improvement wherein a base member of each of said leads is a copper alloy consisting chiefly of copper, an alloy layer consisting of nickel and tin or iron is formed on the whole surface of the base member of each of said leads, a metal plated layer consisting chiefly of copper is formed on portions of the leads exposed from said resinous sealing body, and a solder layer is formed on surfaces of the metal plated layer on the leads exposed from said resinous sealing body.
Claim 3
Dependent Claim 43 words
A semiconductor device according to claim 1, wherein a base member of each of the leads is a copper alloy which consists chiefly of copper, and an alloy layer consisting of tin and nickel is formed on the surface of the base member.
Claim 4
Dependent Claim 43 words
A semiconductor device according to claim 1, wherein a base member of each of the leads is a copper alloy which consists chiefly of copper, and an alloy layer consisting of iron and nickel is formed on the surface of the base member.
Claim 5
Dependent Claim 31 words
A semiconductor device according to claim 1, wherein the metal plated layer consisting chiefly of copper is a copper plated layer which consists of copper and impurities that are inevitably introduced.
Claim 6
Dependent Claim 45 words
A semiconductor device according to claim 1, wherein the metal plated layer consisting chiefly of copper is an alloy plated layer of zinc and copper, which contains 0.05 to 0.2% by weight of zinc, and the balance being copper and impurities that are inevitably introduced.
Claim 7
Dependent Claim 20 words
A semiconductor device according to claim 1, wherein the semiconductor device is of the PLCC (plastic leaded chip carrier) type.
Claim 8
Dependent Claim 19 words
A semiconductor device according to claim 1, wherein the semiconductor device is of the FPP (flat plastic package) type.
Claim 9
Independent Claim 155 words
A method of manufacturing semiconductor devices comprising: a step for bonding a pellet in which is formed a semiconductor integrated circuit with semiconductor elements as main elements, onto a lead frame made of a base member of copper alloy that consists chiefly of copper, the entire surface of said base member being covered with an alloy layer consisting of nickel and tin or iron; a step for bonding the bonding pads of said pellet to corresponding portions of said lead frame via fine metal wires; a step for forming a resinous sealing body by sealing the pellet and peripheries thereof with a resin; a step for forming a copper layer or a copper alloy layer containing 0.05 to 0.2% by weight of zinc on surfaces of the lead frame that are exposed from the resinous sealing body; and a step for forming a solder layer on said copper layer or on said copper alloy layer.
Claim 10
Independent Claim 155 words
A method of manufacturing semiconductor devices comprising: a step for bonding a pellet in which is formed a semiconductor integrated circuit with semiconductor elements as main elements, onto a lead frame made of a base member of copper alloy that consists chiefly of copper, the entire surface of said base member being covered with an alloy layer consisting of nickel and tin or iron; a step for bonding the bonding pads of said pellet to corresponding portions of said lead frame via fine metal wires; a step for forming a resinous sealing body by sealing the pellet and peripheries thereof with a resin; a step for forming a copper layer or a copper alloy layer containing 0.05 to 0.2% by weight of zinc on surfaces of the lead frame that are exposed from the resinous sealing body; and a step for forming a solder layer on said copper layer or on said copper alloy layer.
Claim 11
Dependent Claim 31 words
A method of manufacturing a semiconductor device according to claim 8, wherein said copper layer is formed by plating with copper that consists of copper and impurities which are inevitably introduced.
Claim 12
Dependent Claim 50 words
A method of manufacturing a semiconductor device according to claim 8, wherein said copper alloy layer consisting chiefly of copper is formed by plating an alloy of zinc and copper, which contains 0.05 to 0.2% by weight of zinc, and the balance being copper and impurities that are inevitably introduced.
Claim 13
Dependent Claim 161 words
In a semiconductor device comprising a pellet in which a semiconductor integrated circuit with semiconductor elements as main elements is formed, a plurality of leads that are electrically connected to a plurality of bonding pads of said pellet via fine metal wires, and a resinous sealing body which seals said pellet, said fine metal wires, and portions of said plurality of leads to which said fine metal wires are connected, the improvement wherein a base member of each of said leads is a copper alloy consisting chiefly of copper, an alloy layer composed of a tin-nickel alloy layer or iron-nickel alloy layer is formed on the substantially whole surface of the base member of each of said leads, a metal plated layer consisting chiefly of copper is formed on portions of the leads exposed from said resinous sealing body, and a solder layer is formed on surfaces of the metal plated layer on the leads exposed from said resinous sealing body.
Claim 14
Dependent Claim 161 words
In a semiconductor device comprising a pellet in which a semiconductor integrated circuit with semiconductor elements as main elements is formed, a plurality of leads that are electrically connected to a plurality of bonding pads of said pellet via fine metal wires, and a resinous sealing body which seals said pellet, said fine metal wires, and portions of said plurality of leads to which said fine metal wires are connected, the improvement wherein a base member of each of said leads is a copper alloy consisting chiefly of copper, an alloy layer composed of a tin-nickel alloy layer or iron-nickel alloy layer is formed on the substantially whole surface of the base member of each of said leads, a metal plated layer consisting chiefly of copper is formed on portions of the leads exposed from said resinous sealing body, and a solder layer is formed on surfaces of the metal plated layer on the leads exposed from said resinous sealing body.
Claim 15
Dependent Claim 31 words
A semiconductor device according to claim 11, wherein the metal plated layer consisting chiefly of copper is a copper plated layer which consists of copper and impurities that are inevitably introduced.
Claim 16
Dependent Claim 45 words
A semiconductor device according to claim 11, wherein the metal plated layer consisting chiefly of copper is an allow plated layer of zinc and copper, which contains 0.05 to 0.2% by weight of zinc, and the balance being copper and impurities that are inevitably introduced.
Claim 17
Dependent Claim 20 words
A semiconductor device according to claim 11, wherein the semiconductor device is of the PLCC (plastic leaded chip carrier) type.
Claim 18
Dependent Claim 19 words
A semiconductor device according to claim 11, wherein the semiconductor device is of the FPP (flat plastic package) type.

References Cited (Backward Citations)

JPS522170A Cited
JPS5481777A Cited
JPS54129976A Cited
JPS5567155A Cited
JPS5816044A Cited
JPS5853700A Cited
JPS5958833A Cited
US4441118A Cited
JPS58175852A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-11-16 1991-05-18 1991-11-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-11-16 1995-05-18 1995-11-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-11-16 1999-05-18 1999-11-17 $7700.00 Window Closed / Lapsed

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