Dry Filmpackage for Systemin Packagemolding Process

The stability of packages to protect a MEMS device against molding conditions is simulated and experimentally verified. A finite element method is used to predict the displacement of the cover of the package under influence of molding temperature and pressure. The model is verified using all organic packages of two different materials: ConforMask of Rohm-Haas and TMMF of Tokyo Ohka Kogyo Co. Ltd. The packages are made on wafer scale with a simple two layer dry film process. The process is inexpensive and compatible with CMOS processing. The experimental results were in good agreement with the modeling: the TMMF package (with relatively high Young modulus) withstands the molding pressure.