| 摘要 |
PURPOSE:To enhance the reliability of a bonded part by a method wherein, in a method to form a ball of a composite bonding wire, an electric torch is situated at a position avoiding a region just under the tip of the composite bonding wire and an electric discharge is generated so that the ball whose eccentricity has been retained can be formed at the tip part of the composite bonding wire. CONSTITUTION:An electric torch 4 and a wire 1 are arranged in such a way that the tip part of the wire 1 is situated at the obliquely upper part with refer ence to the electric torch 4 and that the axis of the wire 1 is made vertical. It is arranged that the torch 4 does not exist at the vertically lower part of the wire 1 and that an arc is not formed in a vertical direction. When an arc discharge is generated by arranging the wire 1 and the torch 4 in this manner, the tip part of the wire 1 is fused once; a ball whose eccentricity with reference to the axis of the wire is extremely small can be formed at the tip of the wire 1. |
