Improving the ferroelectric properties of Lu doped Hf0.5Zr0.5O2 thin films by capping a CeO x layer

Lu doped Hf0.5Zr0.5O2 (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 CeOx coating layer, the Lu doped HZO film with the CeOx coating layer has a larger remanent polarization (2P(r) = 34.72 mu C cm(-2)) and presents weaker wake-up behavior, which result from the higher orthogonal phase ratio and the lower oxygen vacancy of the CeOx coated Lu doped HZO film. In addition, the CeOx coating 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.