Three Dimensional Wafer-level Vacuum Packaging of MEMS Resonant Accelerometer

In this work, a novel approach for wafer-level vacuum packaging of MEMS resonant accelerometer is presented and experimentally demonstrated. 3D composite glass-silicon wafer based on glass reflow process is designed and fabricated as carrier wafer. The through glass via (TGV) which is integrated in the composite carrier wafer enables hermetically vertical electrical interconnection for the vacuum packaged MEMS resonant accelerometer. The three dimensional glass lid wafer contains several micro foaming glass caps. The fabricated micro glass caps realize a 2.5mm vertical space for packaged device. The experimental results indicate that utilizing 3D glass cap and composite carrier wafer for vacuum packaging potentially offer a low-cost and effective solution for high performance MEMS resonant accelerometers packaging.