Patent ID: 9278409
Filing Date: 2016-03-08
CPC Classification: B23K,C22C,C22F,H01B,H01L

Claim Text:
1. A core ball, comprising: a sphere-shaped metallic powder forming a core; and a solder plating film coating the surface of said metallic powder; wherein said metallic powder is a sphere in which a metallic degree of purity is equal to or higher than 99.9% but equal to or less than 99.995%, a total contained amount of Pb and/or Bi is equal to or larger than 1 ppm and its sphericity is equal to or higher than 0.95; said solder plating film is a Sn—Bi based Pb-free solder alloy including Bi in an amount of 40-60 mass percent and in which a contained amount of U and Th is equal to or less than 5 ppb respectively; and the alpha dose of said core ball is equal to or less than 0.0200 cph/cm