Patterned Growth of Transition Metal Dichalcogenide Monolayers and Multilayers for Electronic and Optoelectronic...

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• 2D transition metal dichalcogenides (TMDs) possess unique electronic and optical properties.
• Precise patterning of TMDs is crucial for advanced device fabrication.
• Existing methods for TMDs patterning can be complex and costly.

Purpose of the Study:

• To develop a simple, large-area, and cost-effective soft lithographic method for patterned growth of high-quality 2D TMDs.
• To demonstrate the fabrication and performance of electronic and optoelectronic devices using patterned TMDs.
• To explore the potential of patterned TMDs in novel device applications like memristors.

Main Methods:

• Utilizing micromolding in capillaries to pattern liquid precursors (Na2MoO4 aqueous solution) on a substrate.
• Employing chemical vapor deposition to convert precursor patterns into monolayer, few-layer, or bulk TMDs.
• Characterizing patterned TMDs using optical microscopy, AFM, Raman, XPS, SEM, and PL spectroscopy.

Main Results:

• Successful patterned growth of high-quality 2D TMDs with controllable thickness.
• Fabrication of field-effect transistors and photodetectors from patterned TMDs.
• Photodetectors exhibited high responsivity (7674 A W-1) and EQE (1.49 × 10^6 %).
• Patterned TMDs with grain boundaries enabled memtransistor fabrication.

Conclusions:

• The presented soft lithography technique offers a scalable and economical approach for 2D TMDs patterning.
• Patterned TMDs are suitable for high-performance optoelectronic devices and novel applications like memtransistors.
• This technique holds promise for fabricating large-scale TMDs-based device arrays and heterostructures.