EFFECT OF ULTRASONIC VIBRATION ON WIRE BONDING

In order to investigate the effect of ultraronic vibration on wire bonding, an apparatus which enabled compression tests under ultrasonic vibration in a wide range of frequency and amplitude was developed. High purity gold, aluminum and copper specimens were used for the compression test. The apparatus was applied also to the practical wire bonding. The results obtained are as follows. (1) The flow stress is reduced by superimposing the ultrasonic vibration. The stress reduction increases with the increase in frequency and amplitude. (2) The shear strength of wire-bonded interface increases also with the increase in frequency and amplitude. From these results, the effects of ultrasonic vibration on wire bonding are discussed.