Abstract:
A Cu core ball suppresses a soft error and its alpha dose is low. Its surface roughness does not affect a mounting process. A pure degree of the Cu ball as an internal ball is equal to or larger than 99.9% and equal to or less than 95%. 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 equal to or higher than 0.95. A solder plating film coated on the Cu ball is a Sn solder plating film or a solder plating film comprising a lead free solder alloy whose primary component is Sn. In the solder plating film, a contained amount of U is equal to or less than 5 ppb and that of Th is equal to or less than 5 ppb. A total alpha dose of the Cu ball and the solder plating film is equal to or less than 0.0200 cph/cm 2 . An arithmetic average roughness of the Cu core ball is equal to or less than 0.3 µm.
Abstract:
Processes for synthesizing metal nanoparticles, particularly copper nanoparticles, are described. The processes can involve reacting an insoluble complex of a metal salt with a reducing agent in a reaction mixture containing a primary amine first surfactant, a secondary amine second surfactant, and a diamine chelating agent third surfactant. More specifically, processes for forming copper nanoparticles can involve forming a first solution containing a copper salt, a primary amine first surfactant, a secondary amine second surfactant, and a diamine chelating agent third surfactant; allowing an insoluble complex of the copper salt to form from the first solution; combining a second solution containing a reducing agent with the insoluble complex; and forming copper nanoparticles from the insoluble complex. Such copper nanoparticles can be about 10 nm or smaller in size, more particularly about 3 nm to about 6 nm in size, and have a fusion temperature of about 200° C. or lower.
Abstract:
The invention relates to a method for preparing a conductive or semi-conductive element, comprising - providing a dispersion of an anisotropic particulate hybrid material in a continuous phase, which hybrid material comprises (a) anisotropic particles, and (b) a conductive or semi-conductive material or a precursor for a conductive or semi-conductive material; - applying the dispersion to a surface of a substrate; and - forming the conductive or semi-conductive element from the dispersion applied to the surface. Further the invention relates to materials useful for use in a method of the invention and an electronic device obtainable by a method according to the invention.
Abstract:
The present invention provides a powder blend or composite powder that is fed into a kinetic spray device, accelerated towards a substrate or part in order to form a composite solder with thermal and electrical properties better than existing solder. The other advantages of building a solder layer in this manner include a low oxide content to improve subsequent soldcrability, excellent control of the deposition thickness, excellent control of the deposition chemistry and lastly, high speed of manufacture.
Abstract:
A composition may have metal nanoparticles having a diameter of 20 nanometers or less and have a fusion temperature of less than about 220 0C. A method of fabricating the metal nanoparticles may include preparing a solvent, adding a precursor with a metal to the solvent, adding a first surfactant, mixing in a reducing agent, and adding in a second surfactant to stop nanoparticle formation. Copper and/or aluminum nanoparticle compositions formed may be used for lead-free soldering of electronic components to circuit boards. A composition may include nanoparticles, which may have a copper nanocore, an amorphous aluminum shell and an organic surfactant coating. A composition may have copper or aluminum nanoparticles. About 30-50% of the copper or aluminum nanoparticles may have a diameter of 20 nanometers or less, and the remaining 70-50% of the copper or aluminum nanoparticles may have a diameter greater than 20 nanometers.
Abstract:
A method of forming bimetallic core-shell metal nanoparticles including a core of a first metal material and a shell of a second metal material, the method including photochemically producing metallic nanoparticle cores of the first metal material, and forming a shell of the second metal material around the cores. The shell can be formed by adding shell-forming precursor materials to a solution or suspension of the cores and photochemically forming the shells around the cores, or by separately photochemically producing metallic nanoparticles of the second metal material and mixing the metallic nanoparticles of the second metal material and the metallic nanoparticle cores to cause the metallic nanoparticles of the second metal material to form a shell around the metallic nanoparticle cores.
Abstract:
The dielectric-forming composition according to the invention is characterized by consisting of:
composite particles for dielectrics in which part or all of the surfaces of inorganic particles with permittivity of 30 or greater are coated with a conductive metal or a compound thereof, or a conductive organic compound or a conductive inorganic material; and (B) a resin component constituted of at least one of a polymerizable compound and a polymer.
In addition, another dielectric-forming composition according to the invention is characterized by containing:
ultrafine particle-resin composite particles composed of (J) inorganic ultrafine particles with the average particle size of 0.1 µm or smaller, and (B) a resin component constituted of at least one of a polymerizable compound and a polymer, wherein part or all of the surfaces of the inorganic ultrafine particles (J) are coated with the resin component (B), and the ultrafine particle-resin composite particles contain 20% by weight or more of the inorganic ultrafine particles (J); and inorganic particles with the average particle size of 0.1 to 2 µm and permittivity of 30 or greater, or inorganic composite particles in which a conductive metal or a compound thereof, or a conductive organic compound or a conductive inorganic material is deposited on the part or all of the surfaces of the inorganic particles.