Evaluation of Packaging Effect on MEMS Performance: Simulation and Experimental Study

The thermal cure required for die attach during microelectro-mechanical systems (MEMS) packaging causes thermal mismatch that induces undesirable stresses and strains in surface micromachined structures, which may adversely affect the performance and reliability of the packaged component. Understanding the influence of the packaging process is, therefore, critical for successful device design. This paper analyzes the influence of the die attach process on the electromechanical behavior of doubly-anchored surface micromachined beams. A number of different adhesive materials were considered, and the results of parametric studies on the effects of die attach on the pull-in behavior of beams of various lengths, widths, and anchor types are presented. An upward shift in pull-in voltage of the studied devices was observed in both simulation and experiment; modelled and measured data were found to correlate closely.