Stress-Induced Device Degradation Due to Die-Attachment Process after Area Bump Formation

This paper presents the effect of stress on device degradation in metal-oxide-semiconductor field-effect transistors (MOSFETs) due to the die-attachment process after area bump formation. Device degradation increases with increasing stress induced by die-attachment onto an area bump sample. The degradation results mainly from interface trap generation at the Si-SiO2 interface and also from electron trapping in the gate oxide. It is clarified that post-baking at 300°C eliminates the degradation. However, the degradation due to the potting material appears again after post-baking. Therefore, in order to decrease the amount of device degradation due to the packaging process, both the post-baking condition and potting material need to be taken into account when a packaging technology with area bump formation is used.