Figure 6: Schottky barrier height, transition drain voltage and rectification ratio depending on the thickness of MoS2.
From: Ultimate thin vertical p–n junction composed of two-dimensional layered molybdenum disulfide

(a) The barrier height and DT–FNT transition voltage as functions of the MoS2 thickness and layer number. (b) Current rectification ratio as a function of the MoS2 thickness and layer number at various VD (±3, ±2 and ±1 V) levels, indicating a transition between the conventional rectification and reversed rectification at ~8 nm (red dot circle).