Abstract: An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting composition including an adhesion/reaction barrier layer, and having a solder wettable layer reactive with components of a tin-containing lead free solder, so that the solderable layer can be totally consumed during soldering, but a barrier layer remains after being placed in contact with the lead free solder during soldering. One or more lead-free solder balls is selectively situated on the solder wetting layer, the lead-free solder balls comprising tin as a predominant component and one or more alloying components.

Abstract: An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting composition including an adhesion/reaction barrier layer, and having a solder wettable layer reactive with components of a tin-containing lead free solder, so that the solderable layer can be totally consumed during soldering, but a barrier layer remains after being placed in contact with the lead free solder during soldering. One or more lead-free solder balls is selectively situated on the solder wetting layer, the lead-free solder balls comprising tin as a predominant component and one or more alloying components.

Abstract: An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting composition including an adhesion/reaction barrier layer, and having a solder wettable layer reactive with components of a tin-containing lead free solder, so that the solderable layer can be totally consumed during soldering, but a barrier layer remains after being placed in contact with the lead free solder during soldering. One or more lead-free solder balls is selectively situated on the solder wetting layer, the lead-free solder balls comprising tin as a predominant component and one or more alloying components.

Abstract: Methods of forming an aluminum-free wire bond pad and the pad so formed are disclosed. In one embodiment, the method includes forming an opening through a dielectric layer to a last metal of a chip; forming a tantalum nitride (TaN) layer over the chip and over the opening; removing the tantalum nitride (TaN) layer outside of the opening; forming a passivation mask layer over the chip including a passivation mask opening over the last metal; forming a titanium tungsten (TiW) layer and a copper (Cu) layer over the chip; forming a mask layer over the chip including a mask opening to the copper (Cu) layer over the last metal; forming a nickel (Ni) layer and a copper (Cu) layer and then a gold (Au) layer in the mask opening; and removing the mask.

Abstract: Via stack structures are disclosed. In one embodiment, a structure includes a via stack including: a first substantially cross-shaped line in a first dielectric layer; a second substantially cross-shaped line set in a second dielectric layer, and a via stud coupling the first substantially cross-shaped line to the second substantially cross-shaped line. In another embodiment, a structure includes a first via stack, and a second via stack, wherein the first via stack and the second via stack extend in a divergent manner from one another. Each via stack structure is useful for support, for example, in under wire bond applications. The via stack structures can be mixed with other via stack structures and selectively placed within a layout to replace conventional metal plate and via stud array configurations.

Abstract: An electrical structure and method comprising a first substrate electrically and mechanically connected to a second substrate. The first substrate comprises a first electrically conductive pad and a second electrically conductive pad. The second substrate comprises a third electrically conductive pad, a fourth electrically conductive pad, and a first electrically conductive member. The fourth electrically conductive pad comprises a height that is different than a height of the first electrically conductive member. The electrically conductive member is electrically and mechanically connected to the fourth electrically conductive pad. A first solder ball connects the first electrically conductive pad to the third electrically conductive pad. The first solder ball comprises a first diameter. A second solder ball connects the second electrically conductive pad to the first electrically conductive member. The second solder ball comprises a second diameter. The first diameter is greater than said second diameter.

Abstract: The present invention relates to a method for fabricating a semiconductor device with a last level copper-to-C4 connection that is essentially free of aluminum. Specifically, the last level copper-to-C4 connection comprises an interfacial cap structure containing CoWP, NiMoP, NiMoB, NiReP, NiWP, and combinations thereof. Preferably, the interfacial cap structure comprises at least one CoWP layer. Such a CoWP layer can be readily formed over a last level copper interconnect by a selective electroless plating process.

Abstract: A method is provided for removing exposed seed layers in the fabrication of solder interconnects on electronic components such as semiconductor wafers without damaging the interconnects or underlying wafer substrate and with a high wafer yield. The solder interconnects are lead free or substantially lead free and typically contain Sn. An oxalic acid solution is used to contact the wafer after an etching step to remove part of the seed layer. The seed layer is typically a Cu containing layer with a lower barrier layer containing barrier metals such as Ti, Ta and W. The lower barrier layer remains after the etch and the oxalic acid solution inhibits the formation of Sn compounds on the barrier layer surface which compounds may mask the barrier layer and the barrier layer etchant resulting in incomplete barrier layer removal on the wafer surface. Any residual conductive barrier layer can cause shorts and other wafer problems and result in a lower wafer yield.