Anchor designs for thin film packages are disclosed that, in a preferred embodiment are a combination of SiGe-filled trenches and Si-oxide-filled spacing. Depending on the release process, additional manufacturing process steps are performed in order to obtain a desired mechanical strength. For aggressive release processes, additional soft sputter etch and a Ti—TiN interlayer in the anchor region may be added. The ratio of the total SiGe—SiGe anchor area to the SiO2—SiGe anchor area determines the mechanical strength of the anchor. If this ratio is larger than 1, the thin film package reaches the MIL-standard requirements.