On the physics of stiction and its impact on the reliability of microstructures

摘要

Stiction is a very well-known failure mode in micro-electromechanicla systems(MEMS).In this paper,a short overview is givne of the important physical aspects of sticton in microsystems.The surface forcescausing stiction are treated in some detail,and ways of preventing stiction failuresaereviewed from a reliability point of view.,A statistical calculation method to predict stiction failures isreviewed as well,and a more fundamental analysis of the prediction of stiction failures durignnormal operation is outlined.Degradation mechanisms in micro-electromechanicla systems (MEMS0ablejtocausestiction due to a lowering of the restoring force,such as creep and charging of dielectrics,are also discussed.It is difficult to conduct accelerated testing on adhesion,but it is shown that mehcanisms causing a change in the restoring force can be accelerated.Therefore,some stiction failure modes can well be investigatedby accelerated testing.