As the demand of the cheap and thin electronic package is increasing, the need to get more reliable electronic package is also growing. In the past, the pop-corning between L/F and EMC is major cause of the electronic package failure during solder reflow. Since the method to avoid the pop-corning has been improved, the study on the delamination between chip and L/F is needed accordingly.
In this study, the experiments to measure the interfacial fracture toughness between chip and L/F were performed. The cantilever specimen, which is composed of chip, copper L/F and epoxy adhesive and has almost the same thickness as the electronic package used in industry, was prepared to get the load-displacement curve with various temperatures (25℃, 80℃, 150℃, 250℃) and under 85℃/85%RH environmental condition. The F.E.M. was employed to obtain the value of the energy release rate for the specimen at the load drop point appearing in each load-displacement curve. The value of the interfacial fracture toughness, between chip and L/F, is minimum around the $T_g$(130℃) of the chip attach adhesive and is increasing with the increase and decrease of the temperature. The value of the interfacial fracture toughness is decreasing with the increase of the exposure time under 85℃/85%RH environmental condition.
