Switching dynamics of ferroelectric Zr-doped HfO2

Abstract

Ferroelectric Zr-doped HfO2 (HZO) is a promising candidate for steep slope transistors and memory technology. For these applications, it is essential to understand and optimize the switching dynamics of the ferroelectric film. In this work, we characterize the polarization reversal of an 8 nm-thick HZO film deposited by atomic layer deposition with voltage pulses varying in amplitude (0.8 to 2 V) and duration (200 ns to 7.6 ms).We show that the measurements are well described by a nucleation limited switching model, which enables extraction of the minimum switching time and the probability distribution of local electric field variations in the polycrystalline film. The close model fit spanning 5 orders of magnitude in pulse duration indicates the applicability of this model to HZO. This characterization framework can be used to quantify, compare and optimize the switching dynamics of ferroelectric HZO.