Cu-In fine-pitch-interconnects: influence of processing conditions on the interconnection quality

Cu-In fine pitch interconnects are a promising approach for low-temperature technologies in 3D heterogeneous integration. With decreasing structure sizes, the solder material is consumed within little joining durations. The resulting interconnection zone completely exists of intermetallic compounds (IMCs). Due to the unqiue properties of Cu-In-IMCs the interconnection quality of Cu-In fine-pitch interconnects can be affected in a quite tremendous manner when processing conditions are altered. In this work, we address the influence of the bonding duration, the bonding pressure as well as the storage time of as-plated Cu-In microbumps prior to the bonding process.