Reliability studies of bent-beam electro-thermal actuators

This paper reports on the first lifetime studies of the recently developed bent-beam electro-thermal microactuators. Measurements of p/sup ++/ Si bulk micromachined devices under varying operating conditions reveal that device lifetimes and degradation patterns are linked to actuation conditions as well as certain dimensional parameters. Device lifetimes in excess of 30 million cycles are observed. A model similar to that used for fatigue of steel is shown to be very suitable for predicting performance degradation. The model parameters are explored as a function of operating conditions.