  Resistive memory based on 2D WS2, MoS2, and h-BN materials has been studied,
including experiments and simulations. The influences with different active
layer thicknesses have been discussed, including experiments and simulations.
The thickness with the best On/Off ratio is also found for the 2D RRAM. This
work reveals fundamental differences between a 2D RRAM and a conventional oxide
RRAM. Furthermore, from the physical parameters extracted with the KMC model,
the 2D materials have a lower diffusion activation energy from the vertical
direction, where a smaller bias voltage and a shorter switching time can be
achieved. It was also found the diffusion activation energy from the CVD-grown
sample is much lower than the mechanical exfoliated sample. The result shows
MoS2 has the fastest switching speed among three 2D materials.
