Micro-electro-mechanical Systems (MEMS) are miniature electro-mechanical sensor and actuator systems developed from the mature batch-fabricated processes of VLSI technologies. Advances in MEMS design tools and process technologies have resulted in a growth in MEMS applications. This research is exploring testing methodologies for systematically addressing issues of MEMS quality, and a comprehensive MEMS testing methodology is being developed. The approach uses MEMS process simulation to predict the effects that spot contamination has on the physical properties of surface micro-machined sensing devices. Perturbed device properties are mapped to their corresponding faulty behaviors and are used to classify the likelihood and nature of deviant behavior. The resulting MEMS-based fault models are used to develop testing strategies, design-for testability (DFT) techniques, and methods for effective defect diagnosis. Also, testing methods developed for regular CPU circuits, along with techniques from analog and mixed signal testing are being adapted to MEMS testing.
