Tunable Multi-Bit Nonvolatile Memory Based on Ferroelectric Field-Effect Transistors

Ferroelectric field-effect transistors (FeFETs) with 2D semiconductors as channel materials have been fabricated to achieve miniaturized size, high storage, and low power consumption. The FeFETs are studied based on few-layer MoS₂ sheets on the non-lead Bi_0.85La_0.15Fe_0.92Mn_0.08O₃ (BLFMO) ferroelectric films with a large remnant polarization (P_r ≈36 μC cm⁻²). In FeFETs, the conductivity states of the 2D semiconductor can be tuned by the ferroelectric polarization. It is found that the MoS₂-based FeFETs display a large memory windows exceeding 25 V, a high on/off ratio (>10⁵), remarkable program/erase ratio (≈10⁴), competitive retention, endurance, and high-speed performance. Moreover, the 2D based FeFETs exhibit switchable multi-bit data storage by applying different amplitudes of negative gate voltage pulses to enhance the data storage density. On the basis of these characteristics, the 2D-FeFETs are potentially able to meet the need for scalability, capacity, retention, and endurance of nonvolatile memory.