A practical model to analytically characterize the polarization hysteresis of ferroelectric capacitors

A simulation based comparative study of the polarization hysteresis of the ferroelectric capacitor using various ferroelectric models is presented. A 2-dimensional finite element device-level model was implemented using SILVACO´s ATLAS device simulator to generate the polarization hysteresis characteristics for Au/Poly(vinylidene fluoride-trifluoroethylene)/Au metal-insulator-metal (MIM) device. Landau free energy expression for electric field in terms of polarization is also implemented in the MATLAB to produce the polarization hysteresis curve of polycrystalline ferroelectrics. The main drawback of these models was their inability to predict polarization saturation at the same electric field limits for which the experimental device was saturating. A new model for ferroelectric hysteresis based on curve fitting algorithm is derived that forces the polarization to be saturated at desired electric field. The MATLAB simulation of this model and the experimental hysteresis is compared which shows an excellent level of agreement.