Atomic force microscopy (AFM) and scanning probe lithography can be used for the mechanical treatment of various surfaces,
including polymers, metals, and semiconductors. The technique of nanoshaving, in which materials are removed using
the AFM tip, is employed in this work to produce nanopatterns of self-assembled monolayers (SAMs) on two-dimensional
(2D) materials. The materials used are monolayers of transition metal dichalcogenides (TMDs), namely, MoS
2
and WS
2,
which are noncovalently functionalized with perylene diimide (PDI), a perylene derivative. The approach involves rastering
an AFM probe across the surface at a controlled increased load in ambient conditions. As a result of the strong bond between
PDI SAM and TMD, loads in excess of 1 μN are required to pattern the monolayer. Various predefined patterns, including
a grating pattern with feature sizes below 250 nm, are demonstrated. Results indicate the high precision of nanoshaving as
an accurate and nondestructive lithographic technique for 2D materials. The work functions of shaved heterostructures are
also examined using Kelvin probe force microscopy.
«Atomic force microscopy (AFM) and scanning probe lithography can be used for the mechanical treatment of various surfaces,
including polymers, metals, and semiconductors. The technique of nanoshaving, in which materials are removed using
the AFM tip, is employed in this work to produce nanopatterns of self-assembled monolayers (SAMs) on two-dimensional
(2D) materials. The materials used are monolayers of transition metal dichalcogenides (TMDs), namely, MoS
2
and WS
2,
which are noncovale...
»