A Compact Model for Degradation Behaviors in Hf0.2Zr0.8O2 Anti-Ferroelectric Devices

A compact model is developed to describe degradation behaviors of the polarization-voltage (P–V) and current-voltage (I–V) characteristics in Hf0.2Zr0.8O2 (HZO) anti-ferroelectric (AFE) capacitors. It is confirmed that, during field cycling, the evolution of both P–V and I–V characteristics follows the similar rule related to the Kohlrausch-Williams/Watts (KWWs) random-walk relaxation behavior of the switching polarization. The opposite but similar behavior of voltage shift in both characteristics suggests that charge injection should be an underlying mechanism for the observed polarization imprint. The degradation is attributed to the increasing charge defects at the interface between interfacial layer (IL) and the electrode.