MEMS Vacuum Packaging Technology and Applications

Many MEMS (micro electro-mechanic systems) parts have to meet the requirements for vacuum packaging. In vacuum packaging, leakage and gas permeation, which affects the normal function of the components, are major problems. Hermetic sealing is one of the most important technologies for reliable vacuum packaging. In this paper, several hermetic sealing technologies for vacuum packaging was presented, including eutectic bonding, adhesive bonding, glass frit bonding, and silicon-glass anodic bonding. Furthermore, the author introduced two approaches to deal with sealing imperfect surface caused by electric feedthroughs, which link to the outside of the small cavity of MEMS sensors. The getter was discussed as it is essential to keep the vacuum environment inside the cavity of device since the inner walls might release gas after hermetic seal