Aluminum leadframes with two nickel layers
AssigneeTexas Instruments Incorporated
InventorJohn P. Tellkamp
Life of this patent
Estimating the term…
Abstract
A leadframe for use with integrated circuit chips comprising a leadframe base made of aluminum or aluminum alloy having a surface layer of zinc; a first layer of nickel on said zinc layer, said first nickel layer deposited to be compatible with aluminum and zinc; a layer of an alloy of nickel and a noble metal on said first nickel layer; a second layer of nickel on said alloy layer, said second nickel layer deposited to be suitable for lead bending and solder attachment; and an outermost layer of noble metal, whereby said leadframe is suitable for solder attachment to other parts, for wire bonding, and for corrosion protection.
Claims21
A leadframe for use with integrated circuit chips comprising:
- a leadframe base made of aluminum or aluminum alloy having a surface layer of zinc;
- a first layer of nickel on said zinc layer;
- a layer of an alloy of nickel and a noble metal on said first nickel layer;
- a second layer of nickel on said alloy layer, said second;
- and
- an outermost layer of noble metal.
A leadframe for use with integrated circuit chips comprising:
- a leadframe base made of aluminum or aluminum alloy having a surface layer of zinc;
- a first layer of electroless nickel on said zinc layer;
- a second layer of electroplated nickel on said first layer of nickel;
- and
- an outermost layer of noble metal.
A semiconductor device comprising:
- a leadframe comprising a chip mount pad for an integrated circuit chip and a plurality of lead segments having their first end near said mount pad and their second end remote from said mount pad;
- said leadframe made of aluminum or aluminum alloy having a surface layer of zinc, a first layer of nickel, a layer of an alloy of nickel and a noble metal, a second layer of nickel and an outermost layer of noble metal;
- an integrated circuit chip attached to said mount pad;
- and bonding wires interconnecting said chip and said first ends of said lead segments.
A semiconductor device comprising:
- a leadframe comprising a chip mount pad for an integrated circuit chip and a plurality of lead segments having their first end near said mount pad and their second end remote from said mount pad;
- said leadframe made of aluminum or aluminum alloy having a surface layer of zinc, a first layer of nickel over said zinc layer, a layer of an alloy of nickel and a noble metal over said first nickel layer, a second layer of nickel over said alloy layer, and an outermost layer of noble metal over said second layer of nickel;
- an integrated circuit chip attached to said mount pad;
- and
- bonding wires interconnecting said chip and said first ends of said lead segments.
A semiconductor device comprising:
- a leadframe comprising a chip mount pad for an integrated circuit chip and a plurality of lead segments having their first end near said mount pad and their second end remote from said mount pad;
- said leadframe made of aluminum or aluminum alloy having a surface layer of zinc, a first layer of electroless nickel over said zinc layer, a second layer of electroplated nickel over said first layer of nickel, and an outermost layer of noble metal over said second layer of nickel;
- an integrated circuit chip attached to said mount pad;
- and bonding wires interconnecting said chip and said first ends of said lead segments.
Dependencies are inferred from the claim text.