This research studied the thermal fatigue life for eutectic solder balls of thermally enhanced flip-chip plastic ball grid array (FC-PBGA) packages with different lib materials under thermal cycling tests. Three FC-PBGA packages with different lid materia This research studied the thermal fatigue life for eutectic solder balls of thermally enhanced flip-chip plastic ball grid array (FC-PBGA) packages with different lib materials under thermal cycling tests. Three FC-PBGA packages with different lid materia