| 摘要 |
PURPOSE:To reduce the variations of the bonding strengths of respective pads, by storing the frequency of an ultrasonic wave in the case of the bonding of the last time, and by so performing the bondings of the adjacent pads in succession that the stored frequency is used as the starting frequency of the bonding of the next time. CONSTITUTION:In case of the bonding of a pad, a driving unit 10 outputs a pulse signal at such a frequency that its voltage and current phases are made constant respectively, and also, in case of the bonding of each pad, it update- stores in its memory the frequency of the pulse signal every bonding. A bonding tool 5 is subjected to such a positional control that the bondings of the adjacent pads are performed in succession. The driving unit 10 so outputs the pulse signal that the frequency stored in its memory in case of the completion of each bonding is used as the starting frequency of the bonding of the next time, and thereafter, it so controls the frequency of this pulse signal that the voltage and current phases of this pulse signal have a predetermined relation. Thereby, the bonding strengths of the respective pads to respective wires can be made uniform. |
