Evolution of Intermetallic Compound at the Interface between AuSn Solder and Metallization Layer

Abstract:

This paper investigates the intermetallic compound on the interface between AuSn solder and Au or Au/Ni metallization layer after laser soldering by SEM and EDX analysis. The effects of laser power and heating time on the evolution of intermetallic compounds on the interface are discussed. The results show that the components of Jntermetallic compound depart from the eutectic arrest due to Au dissolving quickly into the solder near the interface and forming a stable AusSn at the interface on the condition of laser heating and cooling quickly. With the increase of laser power and heating time, the undissolved Au layer becomes thinner and the AusSn grows into the solder.

Key words:AuSn solder; laser soldering; intermetallic compounds