Wafer-level high vacuum packaging using titanium thin film as bonding and gettering material

Resonant MEMS sensors such as vibratory gyroscope require wafer-level high vacuum packaging to reduce air damping for enhancing a quality factor. Gettering materials such as titanium which adsorb residual gases in the sealed cavity are generally encapsulated inside a package to achieve higher vacuum. In this paper, we propose titanium thin-film for bonding frame as well as gettering material. Wafer-level high vacuum packaging was achieved by the Ti-Ti bonding when thickness of native oxide on Ti surface is well controlled.