摘要
In electronic packaging, underfill materials are commonly applied to fill the gap between chips and substrates, thereby providing additional mechanical support and thermal stability. These different materials within packages resulted in the formation of multiple heterogeneous interfaces, including the underfill/solder interface. Recently, the development of advanced packaging has led to the miniaturization of solder joints and an increase in input/output density, so the interfacial area of underfill/solder interfaces has dramatically increased. In this study, the investigation of interface quality between epoxy and solder was assessed. Atmospheric-pressure plasma was employed to alter the surface properties of solder and improve the interface quality. Additionally, the formation and propagation of cracks can indicate the interface quality of solder joints after the thermal treatment, so a thermal cycling test was adopted to evaluate the reliability of joints after plasma treatment. The results implied that proper plasma treatment could effectively improve the bonding between epoxy and solder interface, yet prolonged plasma treatment could degrade the interface quality.