Achieving Quasi Intrinsic MoS₂ Performance via Liquid-Based Neutralization of Material and Interface Defects with H⁺...

Area of Science:

• Materials Science
• Semiconductor Physics
• Surface Chemistry

Background:

• Semiconductor fabrication creates defects like dangling bonds and charge traps.
• Miniaturization and low-dimensional materials complicate defect mitigation due to potential secondary damage from high-energy treatments.
• Ionized hydrogen in liquid phase offers a potential solution for neutralizing defects via chemical reactions.

Purpose of the Study:

• To verify the mechanism and impact of bis(trifluoromethanesulfonyl)imide (H-TFSI) solution on molybdenum disulfide (MoS₂) field-effect transistors (FETs).
• To distinguish the influence of surface versus gate dielectric interface defects.
• To provide a detailed analysis of interface traps using low-frequency noise characteristics.

Main Methods:

• Treatment of monolayer and multilayer MoS₂ FETs with H-TFSI solution.
• Direct current (DC) measurements for device performance analysis.
• Low-frequency noise measurements to characterize interface traps.

Main Results:

• H-TFSI treatment of multilayer MoS₂ resulted in over a 2-fold increase in carrier mobility.
• Applying negative gate voltage further enhanced mobility by over 3-fold, reaching 128.3 cm²/V s.
• Decreased interface trap density and a positive shift in threshold voltage were observed.

Conclusions:

• Hydrogen ions from H-TFSI effectively heal surface and interface defects in MoS₂ devices.
• H-TFSI demonstrates superior performance in passivating interface traps and neutralizing material defects.
• The study validates the use of H-TFSI for improving MoS₂-based electronic devices.