An all two-dimensional vertical heterostructure graphene/CuInP₂S₆/MoS₂for negative capacitance field effect...

Area of Science:

• Materials Science
• Semiconductor Physics
• Nanotechnology

Background:

• Scaling down transistors increases power dissipation challenges.
• The Boltzmann limit restricts sub-threshold swing (SS) to 60 mV/decade, hindering lower operating voltages.
• Negative capacitance (NC) offers a route to surpass this limit.

Purpose of the Study:

• To demonstrate a NC-FET using an all-2D material heterostructure.
• To break the 'Boltzmann tyranny' and achieve SS below 60 mV/decade.
• To explore the potential of 2D materials for steep slope transistors.

Main Methods:

• Fabrication of a vertical heterostructure using Graphene/CuInP2S6/MoS2.
• Utilizing the negative capacitance effect of CuInP2S6.
• Characterization of the device's electrical performance, focusing on sub-threshold swing.

Main Results:

• Demonstrated a NC-FET with an all-2D material composition.
• Achieved sub-threshold swing values below the Boltzmann limit (< 60 mV/decade), reaching as low as < 10 mV/decade.
• Observed steep switching over three orders of magnitude in source-drain current.

Conclusions:

• The Graphene/CuInP2S6/MoS2 heterostructure successfully implements NC-FET functionality.
• The device breaks the 'Boltzmann tyranny', enabling ultra-steep switching.
• This work presents a promising pathway for developing advanced, low-power steep slope FETs based entirely on 2D materials.