Ferroelectric transistors based on shear-transformation-mediated rhombohedral-stacked molybdenum disulfide

To develop low-power, non-volatile computing-in-memory device using ferroelectric transistor technologies, ferroelectric channel materials with scaled thicknesses are required. Two-dimensional semiconductors, such as molybdenum disulfide (MoS₂), equipped with sliding ferroelectricity could provide an answer. However, achieving switchable electric polarization in epitaxial MoS₂ remains challenging due to the absence of mobile domain boundaries. Here we show that polarity-switchable epitaxial rhombohedral-stacked (3R) MoS₂ can be used as a ferroelectric channel in ferroelectric memory transistors. We show that a shear transformation can spontaneously occur in 3R MoS₂ epilayers, producing heterostructures with stable ferroelectric domains embedded in a highly dislocated and unstable non-ferroelectric matrix. This diffusionless phase transformation process produces mobile screw dislocations that enable collective polarity control of 3R MoS₂ via an electric field. Polarization–electric-field measurements reveal a switching field of 0.036 V nm⁻¹ for shear-transformed 3R MoS₂. Our sliding ferroelectric transistors are non-volatile memory units with thicknesses of only two atomic layers and exhibit an average memory window of 7 V with an applied voltage of 10 V, retention times greater than 10⁴ seconds and endurance greater than 10⁴ cycles.