Passive devices for determining fracture strength of MEMS structural materials

摘要

In microelectromechanical systems (MEMS) device design and fabrication there exists a need for rapid determination of fracture strength. This report describes several passive devices that use the residual stresses contained within structural MEMS materials to determine fracture strength. Stress concentrations of varying degrees are generated at micromachined notch roots, and the critical stress required for failure indicates the fracture strength. A variety of devices have been fabricated from materials such as polysilicon, silicon nitride, and aluminum, with widely varying residual stresses, including devices with both tensile and compressive residual stresses.