Thermosonic flip chip bonding using lateral vibration with anisotropic conductive film (ACF)

In this paper, a new aspect of thermosonic (TS) bonding with anisotropic conductive film (ACF) is presented to take into account the fast curing of ACF. For quick bonding process with ACF, the lateral ultrasonic vibration is applied in parallel to thermocompression (TC) process. The feasibility of TS bonding is demonstrated by experiments for chip-on-glass (COG) bonding. To understand the curing characteristics of the adopted ACF, the measurements with differential scanning calorimeter (DSC) are performed. Moreover, the in-situ temperatures of ACF during TC and TS bonding are measured to show the effect of additional heat generation by lateral ultrasonic vibration.