Gold metallizations for eutectic bonding of silicon wafers
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Gold eutectic bonding of silicon wafers is a good candidate for wafer level vacuum packaging of vibrating MEMS: in this paper we investigated several e-beam evaporated metallizations stacks including a titanium adhesion layer, an optional diffusion barrier (Ni or Pt) and a gold film for eutectic bonding on Si and SiO2/Si wafers. Interdiffusion in the multilayers for annealing temperatures (380–430°C) larger than the Au–Si eutectic temperature (363°C) and times corresponding to a bonding process was characterized by RBS, roughness and resistivity measurements. Au/Pt/Ti and Au/Ti/SiO2 were found to have the best characteristics for bonding. This was confirmed by bonding experiments.
KeywordsSilicon Wafer Gold Film Rutherford Backscatter Spectroscopy Gold Metallization Wafer Bonding
- Plössl A, Kräuter G (1998) Wafer direct bonding: tailoring adhesion between brittle materials. Mater Sci Eng R25:1–88Google Scholar