Failure mechanisms of a MEMS actuator in very high vacuum

摘要: Abstract The tribochemical and mechanical origins of wear a microelectromechanical systems (MEMS) actuator (electrostatic lateral output motor) operated in very high vacuum (10 −7 torr) are reported this study. Failure mechanisms were determined then compared to those dry air, which is one the harshest environments for causing early failure. Durability was poor, even worse than that air. Poor durability related kinetics reformation native oxide at asperity contacts. Devices failed due catastrophic vacuum, more debris generated There fundamental difference morphology devices run In took form pulled-out polysilicon grains. an agglomerate smaller particles, largely comprised SiO 2 . An layer reformed quickly enough air mediated process provide some protection, but resulted oxygen rich debris. passivating removed exposing reactive areas on surface, led junction formation Si–Si It proposed interfacial bonds formed contacts stronger cohesive within polysilicon, grain pull-out adhesive process.