| 摘要 |
PROBLEM TO BE SOLVED: To stably form a bump of high quality, by sparking to a tip part of a wire, forming a ball, transferring the ball cut out from the wire on a board, and bonding the ball to a circuit pattern of the board with pressure. SOLUTION: By sparking to a tip part of a wire 31 constituted of a metal thin wire, a ball 31a is formed on the tip part of the wire 31. The ball 31a is cut out from the wire 31, and the cut ball 31a is transferred on a circuit pattern of a board. The transferred ball 31a is bonded to the circuit pattern of the board with pressure, and a bump is formed. For example, the upper end part of the wire 31 is protruded in a short distance from a box 15, and a ball 31a is formed by sparking from a torch electrode 38. The ball 31a is set on a pedestal 15a, a tool 22 is brought into contact with the ball 31a, and the ball 31a is cut out from the wire 31 with cutters 36, 37. The upper part of the ball 31a is sucked with the tool 22, and the ball 31a is transferred to the board side. |
