Preparation and characterization of hafnium-zirconium oxide ceramics as a CMOS compatible material for non-volatile memories

Hf_xZr_1-xO₂ (HZO) ceramics with x = 0.25, 0.50 and 0.75 were prepared by conventional solid-state reaction technique. Structural studies of the synthesized stoichiometric compounds were done by X-ray diffraction. The microstructure/morphology and composition of ceramics were obtained with field emission-scanning electron microscopy and energy dispersive X-ray, respectively. Impedance spectroscopic studies were done to study the temperature-dependent and frequency-dependent dielectric properties. The dielectric constants at 10 kHz of Hf_xZr_1-xO₂ ceramics were increased from 17 to 40 with Hf varying from 0.25 to 0.75 at ambient conditions. Ferroelectric studies were also done on these compositions with the help of a polarization-electric field plot and are discussed. (author)