The present disclosure relates to a MEMS device with a hermetic sealing structure, and an associated method. In some embodiments, a first die and a second die are bonded at a bond interface region to form a chamber. A conformal thin film structure is disposed covering an outer sidewall of the bond interface region to provide hermetic sealing. In some embodiments, the conformal thin film structure is a continuous thin layer covering an outer surface of the second die and a top surface of the first die. In some other embodiments, the conformal thin film structure comprises several discrete thin film patches disposed longitudinal.