Improving the ferroelectric properties of Lu doped Hf_0.5Zr_0.5O₂thin films by capping a CeO_xlayer

Lu doped Hf_0.5Zr_0.5O₂(HZO) ferroelectric films were prepared on Pt/TiN/SiO₂/Si substrate by chemical solution deposition method, and an interfacial engineering strategy for improving the ferroelectric property was explored by capping the Lu doped HZO films with a cerium oxide layer. Compared with the Lu doped HZO film without the CeO_xcoating layer, the Lu doped HZO film with the CeO_xcoating layer has a larger remanent polarization (2P_r= 34.72µC cm^-2) and presents weaker wake-up behavior, which result from the higher orthogonal phase ratio and the lower oxygen vacancy of the CeO_xcoated Lu doped HZO film. In addition, the CeO_xcoating can remarkably improve the fatigue resistance and retention performance of the Lu doped HZO films. It is hoped that the results can provide an effective approach for the realization of high-performance and highly reliable hafnium oxide based ferroelectric thin films.