Development of Au/Pt/Ti multilayers for wafer-level packaging and residual gas gettering

We demonstrated that Au/Pt/Ti (from top to bottom) metal multilayers enables wafer-level packaging of degassed assemblies and residual gas gettering. A hermetic sealing was fabricated by Au surfaces after degassing annealing at 200°C. In addition, the Ti underlayer atoms diffused to the internal surface by annealing at 450°C, enabling the gas in the package. As the Au/Pt/Ti layers have the functions of the bonding layer and gas getter, the proposed packaging technique can potentially simplify a vacuum sealing process.