Performance study of an ultrasonic transducer used for wire bonding

In-situ studies on the performance of an ultrasonic wire-bonding transducer (about 60 kHz) are presented and discussed in this paper in order to optimize the bonding process. The resonant frequencies and vibration mode shapes of the transducer were computed using finite element method (FEM) and were compared with the experimental resonant frequencies and displacement distributions. Good agreements between the computed and experimental results were obtained. The desirable second axial mode was found and proven to be the dominant mode of the transduces that facilitates the bonding process. Characteristics of the transducer under different input power were also studied. Results show that its performance is good and high quality bonds can be formed.