An in-situ technique for measuring Young´s modulus and residual stress of each layer for multi-layer film

The paper presents an approach to characterize the material properties of multi-layered films using the electrostatic pull-in test structure. The structure is composed of a multi-layered fixed-fixed beam with different widths. An analytical model for the pull-in voltage of the multi-layered fixed-fixed beam with different widths is first presented. The model is then fitted using numerical analysis to improve its accuracy further. Based on this model, a novel in-situ method for simultaneously extracting Young´s modulus and the residual stress of each layer for the multi-layered films is reported. Validation and accuracy of the extracting method have been confirmed by FEM simulation and experiments.