FEM study on the effects of flip chip packaging induced stress on MEMS

Packaging induced stress may have considerable effect on performance of MEMS devices. This paper is focused on the performance change of MEMS devices after flip chip package. The warpage and stress distribution on die surface of flip chip package with different bumps layout are investigated using finite element method (FEM). Package of 4times4 all-array pattern is first studied. Then a comparison study between packages with bumps of 2times2,4times4 and 6times6 all-array patterns and one-circle 4times4, one-circle 6times6 and two-circle 6times6 peripheral patterns are presented. According to the FEM results, the packaging effect on the natural frequency of a flip-chipped microcbridge is case studied finally.