The present disclosure is directed to a hybrid conductive ink including: silver nanoparticles and eutectic low melting point alloy particles, wherein a weight ratio of the eutectic low melting point alloy particles and the silver nanoparticles ranges from 1:20 to 1:5. Also provided herein are methods of forming an interconnect including a) depositing a hybrid conductive ink on a conductive element positioned on a substrate, wherein the hybrid conductive ink comprises silver nanoparticles and eutectic low melting point alloy particles, the eutectic low melting point alloy particles and the silver nanoparticles being in a weight ratio from about 1:20 to about 1:5; b) placing an electronic component onto the hybrid conductive ink; c) heating the substrate, conductive element, hybrid conductive ink and electronic component to a temperature sufficient i) to anneal the silver nanoparticles in the hybrid conductive ink and ii) to melt the low melting point eutectic alloy particles, wherein the melted low melting point eutectic alloy flows to occupy spaces between the annealed silver nanoparticles, d) allowing the melted low melting point eutectic alloy of the hybrid conductive ink to harden and fuse to the electronic component and the conductive element, thereby forming an interconnect. Electrical circuits including conductive traces and, optionally, interconnects formed with the hybrid conductive ink are also provided.

The present disclosure is directed to a hybrid conductive ink including: silver nanoparticles and eutectic low melting point alloy particles, wherein a weight ratio of the eutectic low melting point alloy particles and the silver nanoparticles ranges from 1:20 to 1:5. Also provided herein are methods of forming an interconnect including a) depositing a hybrid conductive ink on a conductive element positioned on a substrate, wherein the hybrid conductive ink comprises silver nanoparticles and eutectic low melting point alloy particles, the eutectic low melting point alloy particles and the silver nanoparticles being in a weight ratio from about 1:20 to about 1:5; b) placing an electronic component onto the hybrid conductive ink; c) heating the substrate, conductive element, hybrid conductive ink and electronic component to a temperature sufficient i) to anneal the silver nanoparticles in the hybrid conductive ink and ii) to melt the low melting point eutectic alloy particles, wherein the melted low melting point eutectic alloy flows to occupy spaces between the annealed silver nanoparticles, d) allowing the melted low melting point eutectic alloy of the hybrid conductive ink to harden and fuse to the electronic component and the conductive element, thereby forming an interconnect. Electrical circuits including conductive traces and, optionally, interconnects formed with the hybrid conductive ink are also provided.

The present disclosure is directed to a hybrid conductive ink including: silver nanoparticles and eutectic low melting point alloy particles, wherein a weight ratio of the eutectic low melting point alloy particles and the silver nanoparticles ranges from 1:20 to 1:5. Also provided herein are methods of forming an interconnect including a) depositing a hybrid conductive ink on a conductive element positioned on a substrate, wherein the hybrid conductive ink comprises silver nanoparticles and eutectic low melting point alloy particles, the eutectic low melting point alloy particles and the silver nanoparticles being in a weight ratio from about 1:20 to about 1:5; b) placing an electronic component onto the hybrid conductive ink; c) heating the substrate, conductive element, hybrid conductive ink and electronic component to a temperature sufficient i) to anneal the silver nanoparticles in the hybrid conductive ink and ii) to melt the low melting point eutectic alloy particles, wherein the melted low melting point eutectic alloy flows to occupy spaces between the annealed silver nanoparticles, d) allowing the melted low melting point eutectic alloy of the hybrid conductive ink to harden and fuse to the electronic component and the conductive element, thereby forming an interconnect. Electrical circuits including conductive traces and, optionally, interconnects formed with the hybrid conductive ink are also provided.

A Cu core ball and a method of manufacturing such a Cu core ball. Purity of the Cu internal ball is at least 99.9% and not greater than 99.995%. A total contained amount of Pb and/or Bi in impurity contained in the Cu ball is equal to or larger than 1 ppm. Its sphericity is at least 0.95. A solder plating film coated on the Cu ball is of Sn solder or a lead free solder alloy whose primary component is Sn. In the solder plating film, a contained amount of U is not more than 5 ppb and that of Th is not more than 5 ppb. A total alpha dose of the Cu ball and the solder plating film is not more than 0./0200 cph/cm2. An arithmetic average roughness of the Cu core ball is equal to or less than 0.3 m.

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.

A Cu core ball is provided that prevents any soft errors and decreases any connection failure. The Cu core ball includes a solder plating film formed on the surface of a Cu ball that is a Sn solder plating film or is made of a lead-free solder alloy, a principal ingredient of which is Sn. The solder plating film contains U of 5 ppb or less and Th of 5 ppb or less. The Cu ball has a purity of not less than 99.9% Cu and not more than 99.995% Cu. Pb and/or Bi contents therein are at a total of 1 ppm or more. The sphericity thereof is 0.95 or more. The obtained Cu core ball has an dose of 0.0200 cph/cm.sup.2 or less.

A Cu core ball is provided that prevents any soft errors and decreases any connection failure. The Cu core ball includes a solder plating film formed on the surface of a Cu ball that is a Sn solder plating film or is made of a lead-free solder alloy, a principal ingredient of which is Sn. The solder plating film contains U of 5 ppb or less and Th of 5 ppb or less. The Cu ball has a purity of not less than 99.9% Cu and not more than 99.995% Cu. Pb and/or Bi contents therein are at a total of 1 ppm or more. The sphericity thereof is 0.95 or more. The obtained Cu core ball has an dose of 0.0200 cph/cm.sup.2 or less.

The present disclosure is directed to a hybrid conductive ink including: silver nanoparticles and eutectic low melting point alloy particles, wherein a weight ratio of the eutectic low melting point alloy particles and the silver nanoparticles ranges from 1:20 to 1:5. Also provided herein are methods of forming an interconnect including a) depositing a hybrid conductive ink on a conductive element positioned on a substrate, wherein the hybrid conductive ink comprises silver nanoparticles and eutectic low melting point alloy particles, the eutectic low melting point alloy particles and the silver nanoparticles being in a weight ratio from about 1:20 to about 1:5; b) placing an electronic component onto the hybrid conductive ink; c) heating the substrate, conductive element, hybrid conductive ink and electronic component to a temperature sufficient i) to anneal the silver nanoparticles in the hybrid conductive ink and ii) to melt the low melting point eutectic alloy particles, wherein the melted low melting point eutectic alloy flows to occupy spaces between the annealed silver nanoparticles, d) allowing the melted low melting point eutectic alloy of the hybrid conductive ink to harden and fuse to the electronic component and the conductive element, thereby forming an interconnect. Electrical circuits including conductive traces and, optionally, interconnects formed with the hybrid conductive ink are also provided.

The present disclosure is directed to a hybrid conductive ink including: silver nanoparticles and eutectic low melting point alloy particles, wherein a weight ratio of the eutectic low melting point alloy particles and the silver nanoparticles ranges from 1:20 to 1:5. Also provided herein are methods of forming an interconnect including a) depositing a hybrid conductive ink on a conductive element positioned on a substrate, wherein the hybrid conductive ink comprises silver nanoparticles and eutectic low melting point alloy particles, the eutectic low melting point alloy particles and the silver nanoparticles being in a weight ratio from about 1:20 to about 1:5; b) placing an electronic component onto the hybrid conductive ink; c) heating the substrate, conductive element, hybrid conductive ink and electronic component to a temperature sufficient i) to anneal the silver nanoparticles in the hybrid conductive ink and ii) to melt the low melting point eutectic alloy particles, wherein the melted low melting point eutectic alloy flows to occupy spaces between the annealed silver nanoparticles, d) allowing the melted low melting point eutectic alloy of the hybrid conductive ink to harden and fuse to the electronic component and the conductive element, thereby forming an interconnect. Electrical circuits including conductive traces and, optionally, interconnects formed with the hybrid conductive ink are also provided.