Optical Soldering of MoS₂ Layers for Defect Structure Formation with Induced Photoluminescence

Abstract

Local manipulation of the defect structures in 2D semiconducting transition metal dichalcogenide (2D TMD) opens rich research avenues harnessing their unique optoelectronic properties, where reliable defect structure formation methods are highly desirable. Here, the concept of optical soldering (OS) on few‐layer MoS2 to form site‐selective defect structures with induced photoluminescence (PL) is proposed and demonstrated. OS is initiated by optical heating of the top MoS2 layer to elevate the local temperature above the melting point of the underlying indium‐tin‐oxide nanoparticles (ITO‐NPs). In turn, thermally deformed ITO‐NPs pull the top MoS2 layer down to the substrate, forming the OS‐induced defect structure on the optically irradiated region. The OS‐induced defect structures on a few‐layer MoS2 show bright PL, which can be manipulated in peak positions by varying the incident optical power and irradiation time. OS is a facile method for local defect structure patterning on few‐layer MoS2 and manipulation of their optoelectronic properties while requiring low incidence optical power (≈2.5 mW) and fast process time (≈1 s), which are beneficial in the development of 2D TMD material‐based applications.