Mechanical stability and adhesion of microstructures under capillary forces. II. Experiments

For pt.I see ibid., vol.2, p. 33 (1993). Strong capillary forces are developed in the fabrication process of surface micromachined structures during the wet etch of sacrificial layers. The magnitude of these forces is in some cases sufficient to deform and pin these structures to the substrate resulting in device failure. The deflection, mechanical stability, and adhesion of thin micromechanical structure under capillary forces are examined. Microstructure adhesion is considered and experimental data for polycrystalline silicon microstructures are presented.>