The effect of ultrasonic frequency on fine pitch aluminum wedge wirebond

This paper describes an analysis of the effect of ultrasonic frequency on aluminum wedge bonds. Wire tensile strength, initial bond force, and ultrasonic power were varied for processes using a standard 60 kHz and a new 120 kHz transducer. Responses measured included wire pull strength and the probability of wire pull lifts, bond width, and bond pad metal "splash". A comparison was made between the two transducers using the methods of designed experiments.