| 摘要 |
PROBLEM TO BE SOLVED: To provide a metallic ball which can keep the soldered strength, and can lower the melting point in soldering. SOLUTION: The metallic ball 10 comprises a core ball 1, a reaction suppressing layer 2, and a plated layer 3. The core ball 1 is made of copper (Cu), and has a diameter within the range from 50μm to 1,000μm. The reaction suppressing layer 2 is made of nickel (Ni), and has a film thickness within the range from 0.1μm to 5μm. The plated layer 3 is made of tin-indium (Sn-In alloy), and has a film thickness within the range from 0.1μm to 100μm. Further, the plated layer 3 is formed by the electroplating in such a manner that the content of tin (Sn) decreases from its innermost periphery toward its outermost periphery, and the content of indium (In) increases from its innermost periphery toward its outermost periphery. COPYRIGHT: (C)2007,JPO&INPIT
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