Fabrication and modeling of 3-D self-assembled SOI MEMS controlled by thermal and plastic strains

Multilayered self-assembled structures are processed based on thin film SOI technology. The assembly relies on the control of the residual stresses building up in multilayered structures undergoing a complete thermal process, including deposition and specific annealing steps. The deflection of multilayered structures made of both elastic and plastic thin films result from the thermal expansion coefficient mismatches and the plastic flow of metallic layers. Finite element simulations confirmed experimental and theoretical results. The process was successfully applied to 3D self-assembled microstructures such as suspended meander inductors and flow sensors.