| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve such problems that some of copper-nucleus soldered balls made from conventional copper balls are unmounted on an adsorption device of a loader, because they can not be adsorbed due to the low sphericity, and when they are bonded to an electronic component by means of melting the solder of the outer coating, the bonding strength is reduced because of fragile intermetallic compounds formed by Sn in the solder and Cu in the copper ball. <P>SOLUTION: The copper micro-ball includes 0.01-0.5 mass% Zn in Cu. Then, the Zn prevents Sn in the solder from combining with Cu in the copper ball, and the bonding strength from lowering. In addition, the method for manufacturing the copper ball is characterized by melting a small piece of an alloy with a large surface tension consisting of 0.5-40 mass% Zn and the balance Cu at a temperature not lower than the melting point of Cu higher, to make spherodized balls. <P>COPYRIGHT: (C)2003,JPO |
