| 摘要 |
PROBLEM TO BE SOLVED: To provide a solder paste capable of properly holding the height of standoff of electronic components, to provide a method for manufacturing spheres for a solder paste, and to provide a method for manufacturing the solder paste. SOLUTION: The dimension and the dispersion distribution of the metallic spheres contained in the solder paste are essentially required to be regulated more strictly. Metallic spheres, which have a melting point higher than a solder constituting a matrix, are dispersed in the solder paste. The mean diameter of the metallic spheres is 50-300μm, and the standard deviation of the diameter distribution is≤2.0μm. The spheres are efficiently obtained at an industrial level by the following suitable method: a metallic chip that has a melting point of≥400°C and quantitatively cut off is introduced into thermal plasma 3; the metallic chip is melted and made spheric in the thermal plasma; and then the formed metallic sphere is cooled and solidified 9 in an inert gas atmosphere as it falls. COPYRIGHT: (C)2005,JPO&NCIPI
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