Voltage and Temperature Acceleration of the Field-Induced Crystallization of Ferroelectric Hafnium Zirconium Oxide

The possibility of an electric field-induced crystallization of hafnium zirconium oxide into its ferroelectric phase enables new device concepts for hardware obfuscation and security applications. While first investigations into the physical mechanism of this effect have been reported, so far, device reliability has not been addressed in detail. In this work, we investigate the temperature and voltage dependence of the field-induced crystallization process as well as the endurance and retention of devices based on hafnium zirconium oxide under elevated temperatures. It is shown that temperature and voltage accelerate the field-induced crystallization. Subsequent endurance studies on the field-induced crystallized samples were conducted and compared to the thermally crystallized samples, even at annealed temperatures up to 200 °C. These findings allow to evaluate the applicability of this effect in future devices for hardware security in e.g. automotive applications. In addition, the field induced crystallization effect for an antiferroelectriclike phase has been shown for the first time.