In this contribution, an innovative deposition and patterning technique for AuSn layer deposition is presented. The
technique allows the deposition of alloys in the Au-Sn-system with a broad range of composition and melting points to
address various chip metallizations and solder hierarchies. The layers can be patterned with high precision
photolithography down to feature sizes of twenty microns at a thickness of up to five microns. For the use in submounts the
solder layers are applied to thin film metallized substrates with different substrate materials, e. g. Al2O3, AlN and Si. The
fabrication method for the layers is presented as well as the methods for quality control in a volume production. Various
applications for AuSn thin film solder layers are shown.