Reliability of wafer level thin film MEMS packages during wafer backgrinding

With the ever-growing number of MEMS resonator applications, an research effort is required. One important step to consider in the design and evaluation phase is the packaging of such a resonator. Packaging has proven to be a problem and this research focuses on the backgrinding of wafers. Backgrinding introduces a tape application and removal step on the active side of the wafer. This paper shows the induced stress profiles on a Wafer Level Thin Film Package (WLTFP) during the tape application step, the stress profiles during removal and evaluates several options to lower the forces acting on the WLTFP in order to increase the survivability.