Defect-Engineered Semiconducting van der Waals Thin Film at Metal-Semiconductor Interface of Field-Effect Transistors

Area of Science:

• Materials Science
• Electronics Engineering
• Nanotechnology

Background:

• Metal-semiconductor interfaces are crucial for electronic device performance.
• Substituting contact metals with semiconductors offers new device functionalities.
• Field-effect transistors (FETs) are key electronic components.

Purpose of the Study:

• To propose a scalable fabrication method for metal-oxide-semiconductor (channel)-semiconductor (interfacial layer) FETs.
• To introduce additional functionalities into FETs by using semiconducting interfacial layers.
• To explore the potential of these devices for multivalued logic and nonvolatile memory.

Main Methods:

• Utilizing solution-processed semiconducting single-walled carbon nanotubes (SWCNTs) as the channel.
• Employing molybdenum disulfide (MoS2) as the interfacial semiconducting layer.
• Modulating the work function of MoS2 by controlling sulfur vacancy concentration via chemical treatment.

Main Results:

• Achieved distinctive energy band alignments within a single device.
• Demonstrated multivalued transistor characteristics and multibit nonvolatile memory (NVM) behavior.
• Developed artificial synaptic devices with 88.9% accuracy in MNIST image recognition.

Conclusions:

• Solution-processed semiconductors offer a scalable route to advanced FETs.
• Tunable interfacial layers enable multi-functional electronic devices.
• These devices show promise for neuromorphic computing applications.