The Top Electrode Tensile Stress Effect on Ferroelectricity of Hf0.5Zr0.5O2 Thin Films

In this report, we have investigated the effect of in-plane tensile stress on ferroelectricity of in Hf 0.5 Zr 0.5 O 2 films, by changing the thickness of TiN top electrode. As demonstrated by residual stress analysis, excessive tensile stress would promote phase transition from the tetragonal phase to the monoclinic phase, and thus degrade the ferroelectric properties in Hf 0.5 Zr 0.5 O 2 films. Our results suggest that there may be an optimal range of tensile stress to improve the ferroelectricity in HZO films.