Influence of antiferroelectric-like behavior on tuning properties of ferroelectric HZO-based varactors

In this article, we investigate the capacitance-voltage (C-V) characteristics of Hf x Zr 1-x O 2 HfxZr1-xO2 metal-ferroelectric-metal (MFM) thin-film capacitors with various Zr doping for varactor applications. The impact of field cycling during the wake-up process on the capacitance was analyzed. In addition, the effect of antiferroelectric-like (AFE) behavior on tuning was investigated. The transition between ferroelectric (FE) and AFE regime is particularly interesting for varactor application, as a reduced bias is required for tuning. The cycle dependence of the FE and AFE properties at elevated temperatures was also investigated, where it was shown that with an increase of temperature, the tunability is reduced. Temperature measurements also comply with recent studies of ferroelastic nature of AFE behavior.