Influence of liquid surface tension on stiction of SOI MEMS

Stiction during the release step is one of the most important problems in micro-electromechanical systems (MEMS). This phenomenon, due to capillary forces and molecular adhesion, appears during drying after wet etching. This force is directly proportional to the surface tension of the last liquid used before drying. In this paper, we present firstly an experimental study of the influence of the liquid surface tension on the stiction of the SOI microstructure. In a second part we show how a new industrial bath process is able to perform the complete release step (etching, rinsing and drying).