Based on the results of the spectroscopic studies, we can describe the exfoliation mechanism as follows. The strong dispersive interaction between the metal substrate and the 2D layer resulted in very strong adhesion between the metal substrate and the constituent elements of the layer, reducing the Mo-S binding energy. This strong adhesion and lattice mismatch at the interface produced a uniform biaxial strain field in the topmost layer of the bulk crystal as suggested by the softening of phonons, particularly the E mode around 380 cm -1 . However, the strain remained relaxed in the adjacent layer (i.e., the second layer) during the "contact period" of the exfoliation process, which was confirmed by the dominant appearance of unchanged E-mode phonons in the bilayer. This large difference of strain between adjacent layers reduces the magnitude of interlayer vdW forces. The dispersive interaction is hindered by the topmost layer due to the sandwich S-Mo-S geometry, as evidenced by the complete restoration of A1 phonons around 400 cm -1 in the bilayer. This synergistic influence of the generated strain and the adhesive force between the metal layer and the topmost MoS2 layer exceeds the interlayer vdW force between the first MoS2 layer on metal and the adjacent one during cleaving/retraction. This in turn enables the selectivity of the exfoliation of only monolayer MoS2. Furthermore, the UHV conditions prevent surface passivation, which cause uniform adhesion of the MoS2 layer with the substrate. The soft support of the crystal on the manipulator enables full contact between the substrate and the parent MoS2 crystal, resulting in an extremely large area of exfoliation.