The ultrasonic wedge/wedge bonding process investigated using in situ real-time amplitudes from laser vibrometer and integrated force sensor

The ultrasonic transversal force transmitted to a chip during ultrasonic bonding is derived from measurements of the vibration amplitude at the tool tip and the die edge. To proof the derivation, the transversal force is measured as well by means of a microsensor, which is sensitive to the stress field in the silicon die. The force measured by the microsensor is further referred to as “y-force” To Al-metalized test pads with the integrated …