(Anti)Ferroelectric HfZrO2: from non volatile memory to energy storage applications
Résumé
Fluorite-structured HfZrO2 and ZrO2 thin films are promising for both non-volatile memory and energy storage applications. Antiferroelectric (AFE) capacitors were fabricated by PE-ALD and annealed using BEOL-compatible thermal budgets. All devices exhibit AFE double hysteresis loops, with polarization strongly dependent on film thickness and annealing temperature. Phase-field modeling reveals thicknessdriven phase transitions enabling low-voltage, high-polarization operation. These characteristics are relevant for future AFE FET. Energy storage performances of linear dielectric (LD), ferroelectric (FE), and AFE films are compared. While FE films show high energy density but large losses, LDs offer high efficiency with low storage density. AFE ZrO2 provides an optimal balance, reaching up to 84 J/cm3 with 75% efficiency. These results position HfZrO2 as a multifunctional platform bridging memory and energy storage technologies.