Constitutive modeling of thin films under thermal cycling

A methodology to derive the elasto-plastic behavior of thin films under thermal cycling is presented. This approach utilizes wafer curvature characterization technique and finite element simulations. The material behavior is modeled with continuum plasticity, and includes Bauschinger effect and cyclic behavior. In order to determine the material parameters, Monte Carlo simulations are performed. The validity of the parameter set is assessed by comparing stress-temperature measurements with the simulated results. This methodology is applied on aluminum thin films to determine the material model parameters and the results are presented here. The developed approach is efficient due to the use of single column of elements in the finite element simulation, which reduces the computational time required for non-linearity and multiple thermal cycle simulations.