▎ 摘 要
Reduced graphene oxide (RGO) thin film was used to improve the performance of a low-temperature bonding process based on Cu microcones and Sn/Cu bumps (diameter: 25 mu m), which has potential applications in high-density packaging. Under bonding conditions of a weight of 1500 g applied to each wafer for 10 min at a temperature of 120 A degrees C, and incorporating a thin RGO layer, a compact bonding structure was obtained without interface voids. The RGO interlayer served as a barrier against interatomic diffusion of metals under zero applied pressure, and the formation of intermetallic compounds at the interface was thereby effectively reduced after bonding. Probable mechanisms for this bonding process are discussed. The investigation used standard 25 mu m-diameter Sn/Cu bumps to simulate realistic industrial production.