Structural and ferroelectric properties of Pr doped HfO2 thin films fabricated by chemical solution method

HfO 2 thin films with different praseodymium doping contents (Pr:HfO 2 ) were fabricated by chemical solution deposition (CSD) method at ambient conditions. The chemical bonding and the composition of Pr doped HfO 2 thin film were characterized by X-ray photoelectron spectroscopy (XPS), while the structural properties were investigated by glancing incidence X-ray diffraction (GIXRD) and high resolution transmission electron microscopy (HRTEM). It is found that the ferroelectric orthorhombic phase was induced in the HfO 2 based thin films by Pr doping. The combined results of P–E (polarization–electrical field) and C–V (capacitance–voltage) measurements demonstrated that the 5 mol% Pr doped HfO 2 film exhibited a distinct ferroelectricity, with a maximum remanent polarization ( P r ) of 6.9 µC/cm 2 and a coercive field ( E c ) of 1.2 MV/cm. Notably, the polarization did not show obvious degradation over 1 × 10 8 switching cycles, suggesting good endurance performance of the Pr doped HfO 2 thin film. These results indicate that Pr dopant could effectively induce ferroelectricity in HfO 2 thin films, thereby becoming a new member of dopants for HfO 2 based ferroelectrics.