Robust giant tunnel electroresistance and negative differential resistance in 2D semiconductor/α-In${}_2$Se${}_3$ ferroelectric tunnel junctions

Ferroelectric tunnel junctions (FTJs) have gained substantial attention as emerging electronic devices such as nonvolatile memory and artificial synapse, owing to their low power consumption and nonvolatile properties. In this work, a 2D semiconductor (2DS)/α-In${}_2$Se${}_3$/metal FTJ structure is proposed that combines a semiconductor ferroelectric material and a semiconducting electrode. The incorporation of 2DS not only enhances the barrier height modulation but also provides an effective approach to mitigate the thermionic current leakage. Notably, the proposed MoS${}_2$/α-In${}_2$Se${}_3$/Ti FTJs exhibit both room-temperature negative differential resistance (NDR) effect and high tunnel electroresistance (TER) exceeding 10${}^4$ simultaneously. Furthermore, the versatility of this structure extends to several 2DS (including MoS${}_2$, PdSe${}_2$, and SnSe${}_2$) and graphene electrodes to rationalize both tunneling and thermionic current transport mechanisms. The proposed 2DS/α-In${}_2$Se${}_3$/metal FTJs present great superiority over existing structures in terms of robustness, temperature independence, high TER, and versatility for various potential application scenarios. (© 2024 Wiley‐VCH GmbH)