| 摘要 |
PURPOSE:To prevent the oxidation of balls, and to contrive the improvement in workability by keeping a discharge part in a perfect gas atmosphere by a method wherein a ball is formed by locating the tip of a wire on the end of a discharge electrode through movement of a capillery. CONSTITUTION:When bonding to the pad of a pellet 4 and the lead 5 finishes, the capillery 2 rises. Thereafter, the capillery 2 moves onto the end 1a of a discharge electrode, thus locating the tip of the wire 3 immediately on the end 1a of a discharge electrode, and a required voltage is impressed between the tip of the wire 3 and the end 1a. A discharge generates thereby, and a ball 3a is formed at the tip of the wire 3. As above, the discharge electrode 1 does not move during ball formation, but the capillery moves; therefore, the discharge part above the end 1a is in a perfect gas atmosphere. Since discharge occurs in a perfect gas atmosphere in such a manner, the oxidation of the ball 3a can be prevented. |
