Design space for stabilized negative capacitance in HfO2 ferroelectric-dielectric stacks based on phase field simulation

Polarization evolution with space and time in HfO2 based metal-ferroelectric-insulator-metal (MFIM) structure is studied on the phase field model by self-consistently solving two-dimensional time-dependent Ginzburg-Landau Poisson equations. Through examining domain wall electrostatic (depolarization) energies compared negative ferroelectric (FE) anisotropy energy, correlation between pattern (phase transition) capacitance (NC) effect revealed for different parameters material properties, including FE thickness gradient coefficient, dielectric permittivity thickness, operation frequency of applied voltage. The design stabilized NC (near) hysteresis-free accompanied voltage amplification limited transition, implying potentials limitations energy-efficient steep-slope devices.