An SOI–MEMS technology using substrate layer and bonded glass as wafer-level package

Abstract We have developed a novel (silicon-on-insulator (SOI), microelectromechanical systems (MEMS)) SOI–MEMS technology combined with anodic bonding process. A metal layer on the glass substrate can provide out-of-plane electrodes and interconnects. More importantly, a wafer-level package of mechanical structures constructed by the top layer of the SOI wafer can be formed by the glass substrate and the substrate layer of the SOI wafer simultaneously. The package can protect fragile mechanical structures during post-release processes, such as dicing, mounting and wire bonding as an ordinary IC wafer. In addition, the wafer-level package can directly provide a specialized package, such as a vacuum package for gyroscopes. No special process other than micromachining is needed.

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