Microstructural characterization of Au/Sn solder for packaging in optoelectronic applications
1998; Elsevier BV; Volume: 29; Issue: 4 Linguagem: Inglês
10.1016/s0968-4328(97)00057-7
ISSN1878-4291
Autores Tópico(s)Intermetallics and Advanced Alloy Properties
ResumoPreliminary results on the feasibility of using co-evaporation of eutectic Au/Sn solder for semiconductor packaging are presented. Gold is electron beam evaporated, while Sn is thermally evaporated, onto Ti/Pt/Au metallized InP substrates. Electron microscopy is utilized to determine the composition and uniformity of the solder and to characterize interfacial reactions between the solder and the semiconductor metallization. Eutectic Au/Sn solder, several microns thick, can be deposited with intermittent substrate cooling. Heating of the solder during simulated reflow experiments results in dissolution of Au and Pt into the solder, with Pt going into substitutional solid solution in AuSn. Part of the Ti layer is consumed as well, forming Au4Ti containing Sn. Bonding tests, reveal solder joints with a uniform distribution of small pores, significantly less than 1 μm in size.
Referência(s)