In this work, we employ analytical models and TCAD simulations to investigate Hf 0.5 Zr 0.5 O 2 (HZO)-based ferroelectric capacitors with and without Al 2 O 3 interlayers, systematically examining the roles of Ginzburg–Landau-Khalatnikov (GLK) parameters, interface charge compensation, domain formation, and grain structure. We demonstrate that basic GLK models predict complete loss of ferroelectricity in the presence of oxide when using HZO parameters extracted from oxide-free devices, in dramatic disagreement with experimental reports showing robust ferroelectric behavior. Attempts to remedy the situation by simple reparametrization will lead to unphysical parameter values. Our results demonstrate that a realistic multi-grain model incorporating interface defect physics and modest variations in ferroelectric parameters is essential to accurately describe experimental devices. Specifically, interface charge compensation via defect traps stabilizes polarization by neutralizing depolarization fields, while multi-grain structures with grain-to-grain variations in coercive field reproduce the experimentally observed gradual switching and increased coercive voltage. This framework provides a physically motivated approach for predictive TCAD simulations of HZO-based ferroelectric devices for advanced computing applications.
Khan et al. (Wed,) studied this question.