An electrical interconnect structure includes a bond pad having a substantially planar bonding surface, and a solder enhancing structure that is disposed on the bonding surface and includes a plurality of raised spokes that are each elevated from the bonding surface. Each of the raised spokes has a lower wettability relative to a liquefied solder material than the bonding surface. Each of the raised spokes extend radially outward from a center of the solder enhancing structure.

A method for producing a joined structure according to the present invention includes: a reflow step of heating a first member and a solder material while keeping them in contact with each other in a reflow chamber to melt a solder alloy constituting the solder material, the reflow step including: a first reflow step of melting the solder alloy with an atmosphere in the reflow chamber reduced to a first pressure P.sub.1 lower than the atmospheric pressure; and a second reflow step of, after the first reflow step, melting the solder alloy with the atmosphere in the reflow chamber reduced to a second pressure P.sub.2 lower than the first pressure P.sub.1.

A method for producing a joined structure according to the present invention includes: a reflow step of heating a first member and a solder material while keeping them in contact with each other in a reflow chamber to melt a solder alloy constituting the solder material, the reflow step including: a first reflow step of melting the solder alloy with an atmosphere in the reflow chamber reduced to a first pressure P.sub.1 lower than the atmospheric pressure; and a second reflow step of, after the first reflow step, melting the solder alloy with the atmosphere in the reflow chamber reduced to a second pressure P.sub.2 lower than the first pressure P.sub.1.

There is provided a conductive particle including a core particle containing a resin material, and a surface layer that covers a surface of the core particle and contains a solder material, in which a melting point of the solder material is equal to or lower than a softening point of the resin material.

Embodiments herein may relate to an apparatus with a package that includes a first substrate soldered to a second substrate via solder comprising an off-eutectic solder material. The off-eutectic solder material may form a joint between the first substrate and the second substrate. The off-eutectic solder material may be any suitable material that melts over a range of temperatures, which may provide a relatively slow collapse of the off-eutectic solder material during a melting process. The relatively slow collapse may provide a sufficient amount of time for gases to escape prior to collapse, and thus, the joint between the first substrate and the second substrate may have less voids compared to joints formed using eutectic solder materials. Other embodiments may be described and/or claimed.

Embodiments herein may relate to an apparatus with a package that includes a first substrate soldered to a second substrate via solder comprising an off-eutectic solder material. The off-eutectic solder material may form a joint between the first substrate and the second substrate. The off-eutectic solder material may be any suitable material that melts over a range of temperatures, which may provide a relatively slow collapse of the off-eutectic solder material during a melting process. The relatively slow collapse may provide a sufficient amount of time for gases to escape prior to collapse, and thus, the joint between the first substrate and the second substrate may have less voids compared to joints formed using eutectic solder materials. Other embodiments may be described and/or claimed.

A conductive connecting member formed on a bonded face of an electrode terminal of a semiconductor or an electrode terminal of a circuit board, the conductive connecting member comprising a porous body formed in such manner that a conductive paste containing metal fine particles (P) having mean primary particle diameter from 10 to 500 nm and an organic solvent (S), or a conductive paste containing the metal fine particles (P) and an organic dispersion medium (D) comprising the organic solvent (S) and an organic binder (R) is heating-treated so as for the metal fine particles (P) to be bonded, the porous body being formed by bonded metal fine particles (P) having mean primary particle diameter from 10 to 500 nm, a porosity thereof being from 5 to 35 volume %, and mean pore diameter being from 1 to 200 nm.

A conductive connecting member formed on a bonded face of an electrode terminal of a semiconductor or an electrode terminal of a circuit board, the conductive connecting member comprising a porous body formed in such manner that a conductive paste containing metal fine particles (P) having mean primary particle diameter from 10 to 500 nm and an organic solvent (S), or a conductive paste containing the metal fine particles (P) and an organic dispersion medium (D) comprising the organic solvent (S) and an organic binder (R) is heating-treated so as for the metal fine particles (P) to be bonded, the porous body being formed by bonded metal fine particles (P) having mean primary particle diameter from 10 to 500 nm, a porosity thereof being from 5 to 35 volume %, and mean pore diameter being from 1 to 200 nm.

Produced is a metal ball which suppresses an emitted dose. Contained are the steps of melting a pure metal by heating the pure metal at a temperature which is higher than a boiling point of an impurity to be removed, higher than a melting point of the pure metal, and lower than a boiling point of the pure metal, the pure metal containing a U content of 5 ppb or less, a Th content of 5 ppb or less, purity of 99.9% or more and 99.995% or less, and a Pb or Bi content or a total content of Pb and Bi of 1 ppm or more, and the pure metal having the boiling point higher than the boiling point at atmospheric pressure of the impurity to be removed; and sphering the molten pure metal in a ball.

Produced is a metal ball which suppresses an emitted dose. Contained are the steps of melting a pure metal by heating the pure metal at a temperature which is higher than a boiling point of an impurity to be removed, higher than a melting point of the pure metal, and lower than a boiling point of the pure metal, the pure metal containing a U content of 5 ppb or less, a Th content of 5 ppb or less, purity of 99.9% or more and 99.995% or less, and a Pb or Bi content or a total content of Pb and Bi of 1 ppm or more, and the pure metal having the boiling point higher than the boiling point at atmospheric pressure of the impurity to be removed; and sphering the molten pure metal in a ball.