Figure 2.

Device characteristics and band diagram of the ultrafast flexible MoS₂ memory. a) Schematic illustration of device structure for electrical measurement. b) Transfer characteristics of MoS₂ memory under different V _CG sweeping ranges (3, 4, 5, 6, and 7 V) and V _DS = 500 mV. c) Memory window extracted from transfer curve with large hysteresis. d) Program and e) erase speed of device demonstrated using different pulse width of V _CG (1 ms, 100 µs, 10 µs, 1 µs, 100 ns) after initialization (V _CG = ±6 V, 1 ms). f) Endurance characteristics of the flexible MoS₂ memory for 1000 cycles under programming (8.5 V, 100 ns) and erase (−7 V, 100 ns) operations at room temperature, where V _DS = 500 mV. g) Retention behavior of device after programming and erasing with a 100 ns pulse, where V _DS = 500 mV. h) Comparison of operation speed of 2D material memories with silicon and flexible substrates. i–k) Schematic band diagram of the MoS₂ memory under i) flat band state, j) program operation (V _CG > 0), and k) erase operation(V _CG < 0). Φ, χ, and E _g represent the work function, the electron affinity, and band gap, respectively.