Electro-thermo-mechanical analytical modeling of multilayer cantilever microactuator

In this paper, we investigate a kind of multilayer cantilever microactuator (MCMA) actuated by Joule heating. The microactuator consists of three film layers, titanium, silicon dioxide and silicon. In light of non-uniform temperature distribution along the MCMA's length, an electro-thermo-mechanical analytical model is developed. The general analytical expression relating tip deflection with an applied voltage, the film thickness and the applied load at the tip is derived. The small deflection (less than 15%) is considered in the model. To evaluate the applicability of the analytical model, the analytical solution is compared with that from 3-D finite element analysis (FEA) and experimental results. The reliability of the analytical model is both device-dependant and temperature-dependant. In this study, the largest error of analytical model against FEA model and experimental data are approximately 13 and 31%, respectively.