Novel Au-Based Solder Alloys: A Potential Answer for Electrical Packaging Problem

With the development of electronical technology and the construction of the fifth-generation cellular networks, electronic devices with higher integrated level and power are widely applied. Hence, greater demands are being placed on electronic packaging materials. High-Pb solder alloys were widely used for low- and medium-temperature soldering for the past decades but have been prohibited due to toxicity. Au-based solder alloys with proper melting and mechanical properties show great potential to replace high-Pb solder alloys and are being emphasized recently. But in comparison with Pb-containing solder alloys, the investigation on novel Au-based solder alloys is quite insufficient, and their performance and reliability are still unclear. In this paper, the recent research studies on Au-based solder alloys with low temperature and medium temperature were reviewed and their microstructure, mechanical performance, and reliability were introduced and analyzed. Moreover, the novel processing technologies of Au-based solder alloys were discussed and compared