Packaging issues using FEA and experimental verification on a Si-based capacitive microrelay

A Si based capacitive microrelay has been packaged in a premolded package and the packaging issues has been studied and verified by FEA and experimental methods. A quasi-3D finite element modeling has been used to understand the thin cap warpage on the microrelay under different process conditions. Experimental verification on the cap warpage showed that thermal loading is not the only contributing parameter for the cap warpage. A modified model with air loading effect and thermal loading effect validated the experimental result. Solution to overcome this problem has been studied with a hole in the package and reinforcement of cap with epoxy.

[1]  Hiroshi Hosaka,et al.  Electromagnetic microrelays: concepts and fundamental characteristics , 1993, [1993] Proceedings IEEE Micro Electro Mechanical Systems.

[2]  Bernd Hillerich,et al.  Micromechanical relay with electrostatic actuation , 1997, Proceedings of International Solid State Sensors and Actuators Conference (Transducers '97).

[3]  David J. Bishop,et al.  Integration and packaging of MEMS relays , 2000, Design, Test, Integration, and Packaging of MEMS/MOEMS.

[4]  C. Lyden,et al.  The importance of molding compound chemical shrinkage in the stress and warpage analysis of PQFPs , 1995 .

[5]  E. Egan,et al.  PBGA warpage and stress prediction for efficient creation of the thermomechanical design space for package-level reliability , 1999, 1999 Proceedings. 49th Electronic Components and Technology Conference (Cat. No.99CH36299).

[6]  J. Schimkat,et al.  Contact materials for microrelays , 1998, Proceedings MEMS 98. IEEE. Eleventh Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Systems (Cat. No.98CH36176.