Abstract: In one embodiment of the present invention, inert nano-sized particles having dimensions from 1 nm to 1,000 nm are added into a solder ball. The inert nano-sized particles may comprise metal oxides, metal nitrides, metal carbides, metal borides, etc. The inert nano-sized particles may be a single compound, or may be a metallic material having a coating of a different material. In another embodiment of the present invention, a small quantity of at least one elemental metal that forms stable high melting intermetallic compound with tin is added to a solder ball. The added at least one elemental metal forms precipitates of intermetallic compounds with tin, which are dispersed as fine particles in the solder.

Abstract: In one embodiment of the present invention, inert nano-sized particles having dimensions from 1 nm to 1,000 nm are added into a solder ball. The inert nano-sized particles may comprise metal oxides, metal nitrides, metal carbides, metal borides, etc. The inert nano-sized particles may be a single compound, or may be a metallic material having a coating of a different material. In another embodiment of the present invention, a small quantity of at least one elemental metal that forms stable high melting intermetallic compound with tin is added to a solder ball. The added at least one elemental metal forms precipitates of intermetallic compounds with tin, which are dispersed as fine particles in the solder.

Abstract: In one embodiment of the present invention, inert nano-sized particles having dimensions from 1 nm to 1,000 nm are added into a solder ball. The inert nano-sized particles may comprise metal oxides, metal nitrides, metal carbides, metal borides, etc. The inert nano-sized particles may be a single compound, or may be a metallic material having a coating of a different material. In another embodiment of the present invention, a small quantity of at least one elemental metal that forms stable high melting intermetallic compound with tin is added to a solder ball. The added at least one elemental metal forms precipitates of intermetallic compounds with tin, which are dispersed as fine particles in the solder.

Abstract: An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting metallurgy 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: A solder joint comprising a solder capture pad on a substrate having a circuit; and a lead containing or a lead free solder selected from the group comprising Sn—Ag—Cu solder, Sn—Cu solder and Sn—Ag solder adhered to the solder capture pad; the solder selected from the group comprising between 0.1 and 6.0 percent by weight Zn. A solder joint, comprising a solder capture pad on a substrate having a circuit; and a Sn—Cu lead free solder adhered to the solder capture pad, the solder comprising between 0.1 and 6.0% by weight Zn. Formation of voids at an interface between the solder and the solder capture pad is suppressed. A method for forming solder joints using the solders.

Abstract: A solder joint comprising a solder capture pad on a substrate having a circuit; and a lead containing or a lead free solder selected from the group comprising Sn—Ag—Cu solder, Sn—Cu solder and Sn—Ag solder adhered to the solder capture pad; the solder selected from the group comprising between 0.1 and 6.0 percent by weight Zn. A solder joint, comprising a solder capture pad on a substrate having a circuit; and a Sn—Cu lead free solder adhered to the solder capture pad, the solder comprising between 0.1 and 6.0% by weight Zn. Formation of voids at an interface between the solder and the solder capture pad is suppressed. A method for forming solder joints using the solders.

Abstract: A solder joint comprising a solder capture pad on a substrate having a circuit; and a lead containing or a lead free solder selected from the group comprising Sn—Ag—Cu solder, Sn—Cu solder and Sn—Ag solder adhered to the solder capture pad; the solder selected from the group comprising between 0.1 and 6.0 per cent by weight Zn. A solder joint, comprising a solder capture pad on a substrate having a circuit; and a Sn—Cu lead free solder adhered to the solder capture pad, the solder comprising between 0.1 and 6.0% by weight Zn. Formation of voids at an interface between the solder and the solder capture pad is suppressed. A method for forming solder joints using the solders.

Abstract: An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting metallurgy 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: Briefly, a novel material process is disclosed wherein one or more nucleation modifiers are added, in trace amounts, to a lead-free tin-rich solder alloy to produce a solder composition with reduce or suppressed undercooling temperature characteristics. The modifier being a substance which facilitates the reduction of extreme anisotropic properties associated with body-centered-tetragonal tin based lead-free solder. The addition of the nucleation modifiers to the solder alloy does not materially effect the solder composition's melting point. As such, balls of solder with the nucleated composition freeze while other solder balls within the array remain in the melt. This effectively enables one substrate to be pinned to another substrate by one or more predetermined solder balls to secure the package while the remaining solder joints are in the liquid state.

Abstract: In one embodiment of the present invention, inert nano-sized particles having dimensions from 1 nm to 1,000 nm are added into a solder ball. The inert nano-sized particles may comprise metal oxides, metal nitrides, metal carbides, metal borides, etc. The inert nano-sized particles may be a single compound, or may be a metallic material having a coating of a different material. In another embodiment of the present invention, a small quantity of at least one elemental metal that forms stable high melting intermetallic compound with tin is added to a solder ball. The added at least one elemental metal forms precipitates of intermetallic compounds with tin, which are dispersed as fine particles in the solder.

Abstract: Briefly, a novel material process is disclosed wherein one or more nucleation modifiers are added, in trace amounts, to a lead-free tin-rich solder alloy to produce a solder composition with reduce or suppressed undercooling temperature characteristics. The modifier being a substance which facilitates the reduction of extreme anisotropic properties associated with body-centered-tetragonal tin based lead-free solder. The addition of the nucleation modifiers to the solder alloy does not materially effect the solder composition's melting point. As such, balls of solder with the nucleated composition freeze while other solder balls within the array remain in the melt. This effectively enables one substrate to be pinned to another substrate by one or more predetermined solder balls to secure the package while the remaining solder joints are in the liquid state.

Abstract: Briefly, a novel material process is disclosed wherein one or more nucleation modifiers are added, in trace amounts, to a lead-free tin-rich solder alloy to produce a solder composition with reduced or suppressed undercooling temperature characteristics. The modifier being a substance which facilitates the reduction of extreme anisotropic properties associated with body-centered-tetragonal tin based lead-free solder. The addition of the nucleation modifiers to the solder alloy does not materially effect the solder composition's melting point. As such, balls of solder with the nucleated composition freeze while other solder balls within the array remain in the melt. This effectively enables one substrate to be pinned to another substrate by one or more predetermined solder balls to secure the package while the remaining solder joints are in the liquid state.

Abstract: Solder balls, such as, low melt C4 solder balls undergo volume expansion during reflow. Where the solder balls are encapsulated, expansion pressure can cause damage to device integrity. A volume expansion region in the semiconductor chip substrate beneath each of the solder balls accommodates volume expansion. Air-cushioned diaphgrams, deformable materials and non-wettable surfaces may be used to permit return of the solder during cooling to its original site. A porous medium with voids sufficient to accommodate expansion may also be used.

Abstract: An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting metallurgy 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: A solder joint comprising a solder capture pad on a substrate having a circuit; and a lead free solder selected from the group comprising Sn—Ag—Cu solder and Sn—Ag solder adhered to the solder capture pad; the solder selected from the group comprising between 0.1 to 2.0% by weight Sb or Bi, and 0.5 to 3.0% Ag. Formation of voids at an interface between the solder and the solder capture pad is suppressed, by including Zn. Interlayer dielectric delamination is suppressed, and electromigration characteristics are greatly improved. Methods for forming solder joints using the solders.

Abstract: A solder joint comprising a solder capture pad on a substrate having a circuit; and a lead free solder selected from the group comprising Sn—Ag—Cu solder and Sn—Ag solder adhered to the solder capture pad; the solder selected from the group comprising between 0.1 to 2.0% by weight Sb or Bi, and 0.5 to 3.0% Ag. Formation of voids at an interface between the solder and the solder capture pad is suppressed, by including Zn. Interlayer dielectric delamination is suppressed, and electromigration characteristics are greatly improved. Methods for forming solder joints using the solders.

Abstract: Briefly, a novel material process is disclosed wherein one or more nucleation modifiers are added, in trace amounts, to a lead-free tin-rich solder alloy to produce a solder composition with reduce or suppressed undercooling temperature characteristics. The modifier being a substance which facilitates the reduction of extreme anisotropic properties associated with body-centered-tetragonal tin based lead-free solder. The addition of the nucleation modifiers to the solder alloy does not materially effect the solder composition's melting point. As such, balls of solder with the nucleated composition freeze while other solder balls within the array remain in the melt. This effectively enables one substrate to be pinned to another substrate by one or more predetermined solder balls to secure the package while the remaining solder joints are in the liquid state.

Abstract: A solder joint comprising a solder capture pad on a substrate having a circuit; and a lead containing or a lead free solder selected from the group comprising Sn—Ag—Cu solder, Sn—Cu solder and Sn—Ag solder adhered to the solder capture pad; the solder selected from the group comprising between 0.1 and 6.0 per cent by weight Zn. A solder joint, comprising a solder capture pad on a substrate having a circuit; and a Sn—Cu lead free solder adhered to the solder capture pad, the solder comprising between 0.1 and 6.0 % by weight Zn. Formation of voids at an interface between the solder and the solder capture pad is suppressed. A method for forming solder joints using the solders.

Abstract: An interconnection structure suitable for flip-chip attachment of microelectronic device chips to packages, comprising a two, three or four layer ball-limiting metallurgy 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: A ball-limiting metallurgy includes a substrate, a barrier layer formed over the substrate, an adhesion layer formed over the barrier layer, a first solderable layer formed over the adhesion layer, a diffusion barrier layer formed over the adhesion layer, and a second solderable layer formed over the diffusion barrier layer.