Figure 4.

Comparison between pristine and laser structured 2D materials by X-ray photoelectron spectroscopy (XPS). (a) Characteristic Pt 4f spectrum of pristine PtSe₂ with the Pt 4f doublet binding energies at 73.3 eV for 4f_7/2 and 76.6 eV for 4f_5/2. (b) Pt 4f orbital of PtSe₂ film exposed using a high-density nanohole pattern (300 nm hole-to-hole pitch) and using low pulse energy (20 pJ). (c) Pt 4f orbital of PtSe₂ film exposed using a low-density nanohole array (1 μm hole-to-hole pitch) and high pulse energy (500 pJ). (d) Characteristic Mo 3d spectrum of the transferred MoS₂ film with the Mo 3d doublet binding energies at 229.4 eV for 3d_5/2 and 232.5 eV for 3d_3/2. (e) Mo 3d orbital of MoS₂ film exposed using a high-density nanohole pattern (300 nm hole-to-hole pitch) and using low pulse energy (100 pJ). (f) Mo 3d orbital of MoS₂ film exposed using a low-density nanohole array (4 μm hole-to-hole pitch) and high pulse energy (500 pJ). (g) Carbon 1s spectrum of the pristine graphene layer with the asymmetric C–C sp² band binding energy at 284.5 eV. (h) Carbon 1s orbital of graphene exposed using a high-density nanohole pattern (300 nm hole-to-hole pitch) and using low pulse energy (150 pJ). (i) C 1s orbital of graphene exposed using a low-density nanohole array (4 μm hole-to-hole pitch) and high pulse energy (500 pJ).