Nonlinear effects and applications of AlN: A comprehensive physical formulation approach

Piezoelectric materials have nonlinear effects that can be used in 5G and IoT technologies. However, since most nonlinear problems in this area do not have analytic solutions, FEM simulations are an essential design tool. In this study, we have developed a stress-charge formulation for non-linear piezoelectric materials compatible with commonly used simulation tools in industry and research. FEM simulation results for AlN with three nonlinear phenomena are presented: variation of effective electrical permittivity, shift of the effective elasticity constants, and enhancement of electromechanical coupling factor. These simulations were conducted with the same material parameters, having great agreement with recent and important experimental results. The simulations allow us to deduce the values of the components of the high-order tensors for the first time as qr_331 = qr_333 = −1600 and g_333 = −80N/V m. The maximum percent errors obtained for the simulations of theeffective electrical permittivity and effective elasticity constants were 0.1% and 1.77%, respectively.