Abstract: A semiconductor device has a leadframe with a structure made of a base metal (105), wherein the structure consists of a chip mount pad (402) and a plurality of lead segments (403). Covering the base metal are, consecutively, a nickel layer (301) on the base metal, and a continuous layer of noble metal, which consists of a gold layer (201) on the nickel layer, and an outermost palladium layer (202) on the gold layer. A semiconductor chip (410) is attached to the chip mount pad and conductive connections (412) span from the chip to the lead segments. Polymeric encapsulation compound (420) covers the chip, the connections, and portions of the lead segments. In QFN devices with straight sides (501), the compound forms a surface (421) coplanar with the outermost palladium layer (202) on the un-encapsulated leadframe surfaces.

Abstract: A metal interconnection for two workplaces such as a semiconductor chip and an insulating substrate. The first workpiece (101) has a first contact pad (201) with a gold stud (110); the second workplace (103) is covered with an insulating layer (213) and a window in the layer to a second contact pad (211). The interconnection between the second pad and the gold stud is a 278° C. eutectic structure (111) with about 80 weight percent gold and about 20 weight percent tin. The eutectic structure has a Young's modulus of 59.2 GPa and a lamellar micro-structure of the phases Au5Sn and AuSn. There is substantially no metallic tin at the second contact pad.

Abstract: A leadframe with a base metal structure (for example, copper) and first and second surfaces. A first metal layer, which is adhesive to polymeric materials such as molding compounds, is adherent to the first leadframe surface. The second leadframe surface is covered by a second metal layer for affinity to reflow metals such as tin alloy; this second metal layer has a different composition from the first metal layer. One example of the first surface is a nickel layer (201) in contact with the base metal (105), a palladium layer (202) in contact with the nickel layer, and an outermost tin layer (203) in contact with the palladium. Another example is an oxidized surface of the base metal. The second metal layer, on the second leadframe surface, comprises a nickel layer (201) in contact with the base metal (105), a palladium layer (202) in contact with the nickel layer, and an outermost gold layer (204) in contact with the palladium layer.

Abstract: A semiconductor device having a leadframe comprised of a base metal (110, e.g., copper), a chip mount pad (103) and a plurality of lead segments (104). Each of the segments has a first end (104a) near the mount pad and a second end (104b) remote from the mount pad. The device further has a semiconductor chip (103) attached to the mount pad and electrical interconnections (107) between the chip and the first segment ends. Encapsulation material (120) covers the chip, the bonding wires and the first segment ends, yet leaves the second segment ends exposed. At least portions of the second segment ends have the base metal covered by a layer of solderable metal (130, e.g., nickel) and by an outermost layer of noble metal (140, e.g., stack of palladium and gold).

Abstract: A leadframe for use in the assembly of integrated circuit chips comprising a base metal structure having an adherent layer of nickel covering said base metal; an adherent film of palladium on said nickel layer; and an adherent layer of palladium on said palladium film, selectively covering areas of said leadframe suitable for bonding wire attachment and solder attachment.

Abstract: A metal structure for a contact pad of a wafer or substrate (101), which have copper interconnecting traces (102) surrounded by a barrier metal layer (103). The wafer or substrate is protected by an insulating overcoat (104). In the structure, the barrier metal layer is selectively exposed by a window (110) in the insulating overcoat. A layer of copper (105), adherent to the barrier metal, conformally covers the exposed barrier metal. Preferably, the copper layer is deposited by sputtering using a shadow mask. A layer of nickel (106) is adherent to the copper layer and a layer of noble metal (106) is adherent to the nickel layer. The noble metal may be palladium, or gold, or a palladium layer with an outermost gold layer. Preferably, the nickel and noble metal layers are deposited by electroless plating.

Abstract: A post-mold plated semiconductor device has an aluminum leadframe (105) with a structure including a chip mount pad and a plurality of lead segments without cantilevered lead portions. A semiconductor chip (210) is attached to the chip mount pad, and conductive connections (212) span from the chip to the aluminum of the lead segments. Polymeric encapsulation material (220), such as a molding compound, covers the chip, the connections, and portions of the aluminum lead segments without leaving cantilevered segment portions. Preferably by electroless plating, a zinc layer (301) and a nickel layer (302) are on those portions of the lead segments, which are not covered by the encapsulation material including the aluminum segment surfaces (at 203b) formed by the device singulation step, and a layer (303) of noble metal, preferably palladium, is on the nickel layer.

Abstract: A method (300) for fabricating a lead frame (100), comprising forming a plurality of external leads (122) in a lead frame material (108), plating a metal (222) on all surfaces of the lead frame material (108), and subsequently forming a plurality of internal leads (124) in the lead frame material (108). The lead frame material (108) may comprise of a portion of a contiguous metal sheeting (204) rolled upon a first coil (202), wherein the contiguous metal sheeting (204) is fed into an external lead stamping apparatus (206), thus forming the external leads (122), and rolled onto a second coil (215). The portion is fed into a plating apparatus and plated with the metal (222), and rolled onto a third coil (218) prior to forming the plurality of internal leads (124). The third coil (218) can be unrolled into an internal lead stamping apparatus (226), thus forming the internal leads (124) of a lead frame (100).

Abstract: An apparatus comprising an insulating substrate having first and second surfaces and a plurality of metal-filled vias extending from the first to the second surface. The first and second surfaces have contact pads, each one comprising a connector stack to at least one of the vias. The stack comprises a seed metal layer in contact with the via metal capable of providing an adhesive and conductive layer for electroplating on its surface, a first electroplated support layer secured to the seed metal layer, a second electroplated support layer, and at least one reflow metal bonding layer on the second support layer. The electrolytic plating process produces support layers substantially pure (at least 99.0%), free of unwanted additives such as phosphorus or boron, and exhibiting closely controlled grain sizes. Reflow metal connectors provide attachment to chip contact pads and external parts.

Abstract: A semiconductor device comprising a semiconductor chip (101) assembled on a first copper cuboid (110); the cuboid has sides of a height (111). The device further has a plurality of second copper cuboids (120) suitable for wire bond attachment; the second cuboids have sides of a height (121) substantially equal to the height of the first cuboid. The back surfaces of all cuboids are aligned in a plane (130). Encapsulation compound (140) is adhering to and embedding the chip, the wire bonds, and the sides of all cuboids so that the compound forms a first surface (140b) aligned with the plane of the back cuboid surfaces and a second surface (140a) above the embedded wires. For devices intended for stacking, the devices further comprise a plurality of vias (160) through the encapsulation compound from the first to the second compound surfaces; the vias are filled with copper, and the via locations are matching between the devices-to-be-stacked.

Abstract: A semiconductor device has a leadframe with a structure made of a base metal (105), wherein the structure consists of a chip mount pad (402) and a plurality of lead segments (403). Covering the base metal are, consecutively, a nickel layer (301) on the base metal, and a continuous layer of noble metal, which consists of a gold layer (201) on the nickel layer, and an outermost palladium layer (202) on the gold layer. A semiconductor chip (410) is attached to the chip mount pad and conductive connections (412) span from the chip to the lead segments. Polymeric encapsulation compound (420) covers the chip, the connections, and portions of the lead segments. In QFN devices with straight sides (501), the compound forms a surface (421) coplanar with the outermost palladium layer (202) on the un-encapsulated leadframe surfaces.

Abstract: A metal structure (100) for a contact pad of a semiconductor device, which has interconnecting traces of a first copper layer (102). The substrate is protected by an insulating overcoat (104). In the structure, the first copper layer of first thickness and first crystallite size is selectively exposed by a window (110) in the insulating overcoat. A layer of second copper (105) of second thickness covers conformally the exposed first copper layer. The second layer is deposited by an electroless process and consists of a transition zone, adjoining the first layer and having copper crystallites of a second size, and a main zone having crystallites of the first size. The second thickness is selected so that the distance a void from the second layer can migrate during the life expectancy of the structure is smaller than the combined thicknesses of the first and second layers. A layer of nickel (106) is on the second copper layer, and a layer of noble metal (107) is on the nickel layer.

Abstract: A metal structure for a contact pad of a wafer or substrate (101), which have copper interconnecting traces (102) surrounded by a barrier metal layer (103). The wafer or substrate is protected by an insulating overcoat (104). In the structure, the barrier metal layer is selectively exposed by a window (110) in the insulating overcoat. A layer of copper (105), adherent to the barrier metal, conformally covers the exposed barrier metal. Preferably, the copper layer is deposited by sputtering using a shadow mask. A layer of nickel (106) is adherent to the copper layer and a layer of noble metal (106) is adherent to the nickel layer. The noble metal may be palladium, or gold, or a palladium layer with an outermost gold layer. Preferably, the nickel and noble metal layers are deposited by electroless plating.

Abstract: A method (300) for fabricating a lead frame (100), comprising forming a plurality of external leads (122) in a lead frame material (108), plating a metal (222) on all surfaces of the lead frame material (108), and subsequently forming a plurality of internal leads (124) in the lead frame material (108). The lead frame material (108) may comprise of a portion of a contiguous metal sheeting (204) rolled upon a first coil (202), wherein the contiguous metal sheeting (204) is fed into an external lead stamping apparatus (206), thus forming the external leads (122), and rolled onto a second coil (215). The portion is fed into a plating apparatus and plated with the metal (222), and rolled onto a third coil (218) prior to forming the plurality of internal leads (124). The third coil (218) can be unrolled into an internal lead stamping apparatus (226), thus forming the internal leads (124) of a lead frame (100).

Abstract: A leadframe with a structure made of a base metal (105), wherein the structure has a plurality of surfaces. On each of these surfaces are metal layers in a stack adherent to the base metal. The stack comprises a nickel layer (201) in contact with the base metal, a palladium layer (202) in contact with the nickel layer, and an outermost tin layer (203) in contact with the palladium layer. In terms of preferred layer thicknesses, the nickel layer is between about 0.5 and 2.0 ?m thick, the palladium layer between about 5 and 150 nm thick, and the tin layer less than about 5 nm thick, preferably about 3 nm. At this thinness, the tin has no capability of forming whiskers, but offers superb adhesion to polymeric encapsulation materials, improved characteristics for reliable stitch bonding as well as affinity to reflow metals (solders).

Abstract: A leadframe with a base metal structure (for example, copper) and first and second surfaces. A first metal layer, which is adhesive to polymeric materials such as molding compounds, is adherent to the first leadframe surface. The second leadframe surface is covered by a second metal layer for affinity to reflow metals such as tin alloy; this second metal layer has a different composition from the first metal layer. One example of the first surface is a nickel layer (201) in contact with the base metal (105), a palladium layer (202) in contact with the nickel layer, and an outermost tin layer (203) in contact with the palladium. Another example is an oxidized surface of the base metal. The second metal layer, on the second leadframe surface, comprises a nickel layer (201) in contact with the base metal (105), a palladium layer (202) in contact with the nickel layer, and an outermost gold layer (204) in contact with the palladium layer.

Abstract: A semiconductor device having a leadframe comprised of a base metal (110, e.g., copper), a chip mount pad (103) and a plurality of lead segments (104). Each of the segments has a first end (104a) near the mount pad and a second end (104b) remote from the mount pad. The device further has a semiconductor chip (103) attached to the mount pad and electrical interconnections (107) between the chip and the first segment ends. Encapsulation material (120) covers the chip, the bonding wires and the first segment ends, yet leaves the second segment ends exposed. At least portions of the second segment ends have the base metal covered by a layer of solderable metal (130, e.g., nickel) and by an outermost layer of noble metal (140, e.g., stack of palladium and gold).

Abstract: A leadframe for use in the assembly of integrated circuit chips comprising a base metal structure having an adherent layer of nickel covering said base metal; an adherent film of palladium on said nickel layer; and an adherent layer of palladium on said palladium film, selectively covering areas of said leadframe suitable for bonding wire attachment and solder attachment.

Abstract: An apparatus comprising an insulating substrate (101) having first and second surfaces (101a, 101b) and a plurality of metal-filled vias (102) extending from the first to the second surface. The first and second surfaces have contact pads (103, 104), each one comprising a connector stack to at least one of the vias. The stack comprises a seed metal layer (110, copper) in contact with the via metal capable of providing an adhesive and conductive layer for electroplating on its surface, a first electroplated support layer (111a, copper) secured to the seed metal layer, a second electroplated support layer (111b, nickel), and at least one reflow metal bonding layer (112, palladium, gold) on the second support layer. The electrolytic plating process produces support layers substantially pure (at least 99.0%), free of unwanted additives such as phosphorus or boron, and exhibiting closely controlled grain sizes. Reflow metal connectors (220, 230) provide attachment to chip contact pads and external parts.

Abstract: The invention relates to a tire having a rubber tread comprised of cap/base construction where the tread cap layer provides the running surface of the tread and the tread base layer underlies the tread cap layer and thereby provides a transition between the tread cap layer and the tire carcass. For this invention, the tread cap layer is comprised of a plurality of individual circumferential load-bearing zones of rubber compositions, which exhibit graduated physical properties, and which extend from the outer running surface of the tread cap layer radially inward to said tread base layer. In one aspect, the zoned rubber tread cap layer and rubber tread base layer are co-extruded together to form a unit as an integral tread rubber composite.