Abstract:
The present invention relates to an inorganic powder having a frequency-size distribution with multiple peaks, wherein the peaks are present at least in the particle size regions from 0.2 to 2 µm and from 2 to 63 µm, preferably with the maximum particle size being 63 µm or less, the average particle size being from 4 to 30 µm, and the mode size being from 2 to 35 µm. The inorganic powder of the present invention is useful as a filler for a high thermally conductive member in electronic component-mounted circuit board required to have electrical insulating property and heat radiating performance, in that a heat radiating member comprising the powder can have thermal conductivity, the powder can provide a resin composition having excellent withstand voltage characteristics for forming an insulative composition into a thin film and can be filled in the resin composition at a high density so as to improve heat radiating performance of the resin composition.
Abstract:
The present invention aims at providing a high-temperature lead-free solder material which can form a solder joint of improved heat resistance and reliability, and is suitable for application to dual-temperature solder connection, and a method of soldering an electronic part. According to the invention a solder cream is obtained by kneading an Sn-Ag-Cu alloy with a flux, wherein the Sn-Ag-Cu alloy comprises a mixture of a first powder alloy containing 10 to 30% by weight of Ag and 2 to 20% by weight of Cu with a balance consisting of Sn and unavoidable impurities, and a second powder alloy containing smaller compositions (% by weight) of Ag and Cu than the first powder alloy, and having a melting point lower than that of the first powder alloy, the mixture containing a total of not more than 35% by weight of Ag and Cu.
Abstract:
The invention relates to conductive inks obtained by combining AQCs and metal nanoparticles. Atomic quantum clusters (AQCs), which melt at temperatures of less than 150°C, are used as low-temperature "flux" for the formulation of conductive inks. The combination of AQCs with bimodal and trimodal mixtures of nanoparticles of various sizes guarantees the elimination of free volumes in the final sintering of the nanoparticles in order to achieve electronic structures with very low resistivity (close to that of the bulk material) with low-temperature thermal treatments (
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:
Die Erfindung betrifft ein Verfahren zum Herstellen von Kontaktstellen (10) aus einer Leitpaste (2) auf einem Träger (1), insbesondere einer Leiterkarte, wobei die Leitpaste (2) ein Flussmittel und zumindest einen leitenden Werkstoff aufweist, der als Körner (11) in der Leitpaste (2) enthalten ist, mit den folgenden Schritten: Anbringen einer Schablone (3) mit Öffnungen (6,14), die die Kontaktstellen auf dem Träger (1) festlegen, Einbringen der Leitpaste (2) in die Öffnungen (6,14) der Schablone (3), wobei mithilfe eines Rakels (9) die Leitpaste (2) auf der Schablone (3) verteilt und in die Öffnungen (6,14) gedrückt wird und Aufschmelzen der Leitpaste (2), wobei eine verschmolzene Schicht auf dem Träger (1) ausgebildet wird. Die Leitpaste weist Körner auf, deren Durchmesser überwiegend, insbesondere wenigstens zu 80 Prozent, im Bereich von 15 bis 40 Mikrometer liegt, und die Schablone weist im Bereich der Öffnungen (6,14) eine Dicke bis zu 50 Mikrometer auf.