Abstract: The specification describes a method for attaching semiconductor components to a substrate wafer by solder bump bonding using gold tin eutectic solder bumps. The process involves first forming solder stacks by blanket evaporation of a stack layer comprising a first layer of gold, a layer of tin and a second layer of gold, and patterning the stack layer by lift-off to form individual solder stacks. Attachment is effected by reflow of the solder stacks to bump bond the components to the substrate wafer. The quality of the bump bond is improved by annealing the multilayer stack, prior to reflow, to diffuse tin toward the stack surface.