Cutting, Nanoexfoliation,\nand Reshaping of Multilayer\nMoS<sub>2</sub> Using Atomic Force Microscopy-Based Thermomechanical\nScratch

Atomically thin two-dimensional (2D) layered materials,\nsuch as\nmolybdenum disulfide (MoS<sub>2</sub>), are candidates for next-generation\nnanoelectronic and optoelectronic devices. Patterning 2D materials\ninto finite nanostructures is essential for system integration and\nwafer-scale manufacturing but remains a major challenge. Herein, a\nthermomechanical nanolithography technique is demonstrated that allows\nfor the direct cutting, nanoexfoliation, and reshaping of multilayer\nMoS<sub>2</sub> on a flexible poly(methyl methacrylate) (PMMA) substrate\nusing a heated atomic force microscope nanotip. Using a constant force\nof 735 nN, a 3.8 nm-thick MoS<sub>2</sub> was cut to form notches,\nnanoexfoliated, and reshaped under the heating temperatures of 120\nto 170 °C induced by the great tensile stress produced via thermomechanical\ncleaving of the thermosensitive PMMA underneath the MoS<sub>2</sub>. However, under given parameters of 735 nN and 170 °C, the\nthickness of 4.4 nm was the limit thickness that MoS<sub>2</sub> can\nbe cut, peeled, and reshaped due to the markedly increased bending\nstiffness and strain energy with the enlarged thickness. The proposed\ndirect manipulation technique of multilayer MoS<sub>2</sub> is a promising\ntool for precisely tailoring nanopatterns on 2D materials for future\napplications in flexible nanoelectronic and optoelectronic devices.