Thermal-Assisted Vertical Electron Injections in Few-Layer Pyramidal-Structured MoS₂ Crystals

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Atomically thin two-dimensional (2D) materials, like molybdenum disulfide (MoS2), are vital for advanced electronics and optoelectronics.
• Understanding interlayer screening and charge transport is key, but largely unexplored in chemical vapor deposition (CVD)-grown MoS2.

Purpose of the Study:

• To investigate interlayer screening effects and charge conduction mechanisms in CVD-grown MoS2 crystals.
• To characterize controllable CVD-grown monolayer and pyramidal-structured MoS2 crystals.

Main Methods:

• Controlled synthesis of monolayer and pyramidal-structured MoS2 using CVD with an oxidized Mo foil precursor.
• Electrical measurements and analysis of vertical charge transport mechanisms.

Main Results:

• Demonstrated controllable CVD growth of MoS2 structures.
• Identified Richardson-Schottky (RS) emission as the dominant charge transport mechanism for bias voltages less than 1V.
• Showed that the Fowler-Nordheim (FN) tunneling model does not adequately explain the observed electrical behavior.

Conclusions:

• The study provides a fundamental understanding of charge conduction in CVD-grown MoS2.
• Findings challenge the applicability of the FN model for these specific MoS2 interfaces.
• The results are crucial for the future development of MoS2-based electronic and optoelectronic devices.