Application of flip-chip-bonders in AuSn solder processes to achieve high after bonding accuracy for optoelectronic modules

The application of AuSn solder processes to achieve high after bonding accuracy for optoelectronic modules using a high accuracy flip-chip bonder was investigated. The different requirements of the modules were matched by adjusting the metallization layers of the bond pads, the solder deposition and the bonding parameters. The -phase contact was obtained under Au80Sn20 reflow conditions. Working with -phase offers the possibility to work with the fluxfree Au80Sn20 metallurgy on different assembly levels of optoelectronic modules without remelting the interconnections soldered at previous assembly steps.