Ferroelectric and antiferroelectric properties of Si-doped HfO2 thin films

Ferroelectric and antiferroelectric HfO2 nano-films were prepared by changing silicon doping concentration, and their basic properties were compared in terms of polarization hysteresis, capacitance-voltage and leakage-voltage behavior, as well as the effect of temperature on phase stability. Antiferroelectric thin film exhibits a higher dielectric constant than the ferroelectric film, and is characterized by the double polarization hysteresis loops due to reversible antiferroelectric-ferroelectric phase transition induced during loading and unloading processes of electric field. No antiferroelectric-paraelectric phase transition is observed at measuring temperatures up to 185 degrees C. The negative differential resistivity effect observed in leakage measurements is attributed to the contributions from slow response mechanisms like polarization relaxation.