| 摘要 |
PROBLEM TO BE SOLVED: To manufacture solder ball electrodes easily at low cost by moving pellet-shaped solder pieces which are punched from a long and thin solder plate onto lands and melting them by reflow. SOLUTION: Pellet-shaped solder pieces 18 are punched from a long and thin solder plate (solder ribbon 15) which is easy to manufacture and handle using a punching die (die head 17) which corresponds to the arrangement of electrodes (arrangement of lands) of a BGA package 1. After that, the pellet- shaped solder pieces 18 are moved onto lands of the BGA package 1. At that time, the die head 17 can be used as a suction head. Finally, the solder pieces are melted by reflow. By this method, solder ball electrodes 2 of a desired shape can be formed. In order to form solder balls of 0.76m in diameter, the pellet-shaped solder pieces 18 of 0.8552mm in diameter should be punched at a pitch of 1.27mm if the thickness of the solder ribbon 15 is 0.4mm. |
