Effect of La and Y on Crystallization Temperatures of Hafnia and Zirconia

Abstract

Crystallization of amorphous Y- and La-doped HfO2 and ZrO2 nanophase powders was studied using thermal analysis and high-temperature x-ray diffraction. Substantial increase of crystallization temperature of amorphous hafnium and zirconium oxides could be achieved by alloying with La2O3. The crystallization temperature of Hf2La2O7 composition is higher than 900 °C, which makes it a candidate for advanced gate dielectrics. In contrast, Y-doping did not significantly raise the crystallization temperature.