Effect of La and Y on crystallization temperatures of hafnia and zirconia

摘要

Crystallization of amorphous Y- and La-doped HfO_2 and ZrO_2 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 La_O_3. The crystallization temperature of Hf2_La_2O_7 composition is higher than 900 deg C, which makes it a candidate for advanced gate dielectrics. In contrast, Y-doping did not significantly raise the crystallization temperature.