Electroresistance effect in MoS2-Hf0.5Zr0.5O2 heterojunctions

Abstract

Pairing two-dimensional semiconductors with ferroelectric films may allow for the development of hybrid electronic devices that would not only exhibit a combination of the functional properties of both material groups but would also reveal unusual characteristics emerging from coupling between these properties. Here, we report the observation of a considerable (up to 10³ at 0.8 V read bias) polarization-mediated tunneling electroresistance (TER) effect in Hf₀.₅Zr₀.₅O₂ (HZO) ferroelectric tunnel junctions (FTJs) employing MoS₂ as one of the electrodes. It was found that for this type of hybrid FTJs, a change in resistance upon polarization reversal could be described by Fowler–Nordheim tunneling. The underlying mechanism for the enhanced TER effect is a polarization-mediated accumulation or depletion of the majority carriers at the MoS₂/HZO interface, which results in a change in the effective barrier shape seen by the tunneling electrons. Given the compatibility of HfO₂-family ferroelectrics with CMOS technology and a possibility of large scale growth and transfer of MoS₂ films, our results provide a pathway for fabrication of high-density nonvolatile memory and data storage systems based on hybrid FTJs.