| 摘要 |
PURPOSE:To surely detect cut wire or Au-ball formation failure by a method wherein light emitted at the time of Au-ball formation by discharge is detected, and it is judged as wire cut when the amount of light is less than a set value. CONSTITUTION:A timing signal is fed from a bonding controller 1 to the spark power source 2, when a discharge occurs between an Au fire wire tip 6 and the electrode 7. When discharge occurs, a high temperature generates, and an Au ball is formed by the fusion of the tip 6, and at the same time a light is emitted. A light receiving element 9 converts light into voltage by sensing the emitted light. This element 9 is strongly directive, and a detection amplifying unit 10 has the function of sensitivity adjustment and transmits detection signals only when detecting a portion of light over a set amount at the position where discharge can occur. As a result, since this unit 10 does not transmit detection signals to the bonding controller 1 when becoming short in the amount of generated light on account of wire cuts of Au-ball formation failure, the bonding controller 1 judged as wire cuts and stops bonding not to transfer to the next bonding process. |
