Effect of tool drop on the performance of a high-frequency piezoelectric wire-bonding transducer system

This work describes a method to determine a suitable tool drop for clamping the bonding tool in a high-frequency (130 kHz) piezoelectric horn transduc er used for wire bonding. Effect of different tool drops on four critical p arameters, namely, the resonant frequency, the electrical impedance, the ph ase angle, and the tool tip displacement amplitude, were studied with the t ransducer system being driven at normal bonding power. Strong interdependen ce was observed among these parameters. The results were interpreted from t he system stability and other physical point of views. Appropriate ranges o f tool drop were found. With the tool drop in these ranges, it can produce desirable characteristics for the wire bonding.