Abstract
The purpose of this study is to clarify the joint behavior during ultrasonic flip chip bonding using the in-situ bonding monitoring method with the semiconductor strain sensor. Some characteristic tendencies related with the bonding strength ware extracted from the strain waves below the joint region. The higher the bonding strength was, the bigger reduction of the vertical compression strain during applying ultrasonic vibration was. Furthermore, the joint status was found to be correlated with the change in the amplitude and harmonic components of the horizontal strain with time. Especially, the difference in harmonic components of each wave was very useful as the future value of the machine learning algorithms for judging bonding qualities.
