| 摘要 |
PURPOSE:To provide a wire bonding device which controls the crystal structure of a ball formed at the leading edge of wire. CONSTITUTION:A timer circuit 11 is driven by a trigger signal from a control circuit 10 and a high-frequency oscillator 12 oscillates. Based on the oscillation of the high-frequency oscillator 12, switching transistors Q1 and Q2 are alternately turned on and the primary side coil 15 of a step up transformer 14 is supplied with high-frequency current. The secondary side output of the step up transformer 14 is superimposed with direct current bias supplied from a constant current circuit 18 or 21 to be applied between wire 7 and a discharge electrode 9 and electric discharge is performed between the leading edge of the wire 7 protruded from the edge of a capillary 8 and the discharge electrode 9. At that time, spark operation is changed in response to the quantity of the direct current bias and the crystal structure of a ball being formed at the leading edge of the wire is controlled. |
