Two-terminal nonvolatile memories based on single-walled carbon nanotubes

Area of Science:

• Materials Science
• Nanotechnology
• Electronics

Background:

• Semiconducting single-walled carbon nanotubes (SWCNTs) are promising for electronic applications.
• Reproducible current hysteresis is a key phenomenon for memory devices.
• Two-terminal configurations offer simplified device architectures.

Purpose of the Study:

• To investigate reproducible current hysteresis in SWCNTs without a gate electrode.
• To realize a two-terminal nonvolatile memory device based on observed hysteresis.
• To elucidate the mechanism behind the hysteresis and switching behavior.

Main Methods:

• Electrical characterization of SWCNTs in a two-terminal setup.
• Application of voltage pulses to induce switching.
• Analysis of current-voltage (I-V) characteristics.
• Correlation of switching behavior with SWCNT carrier types and interface properties.

Main Results:

• Observed reproducible current hysteresis in semiconducting SWCNTs.
• Successfully demonstrated a two-terminal nonvolatile memory device.
• Identified charge trapping at the SWCNT/SiO2 interface as the primary mechanism.
• Showcased a direct transition of hysteresis evolution due to changes in carrier type induced by air adsorbates.

Conclusions:

• Charge trapping at the SWCNT/SiO2 interface is responsible for reproducible hysteresis in SWCNTs.
• The developed two-terminal device functions as a nonvolatile memory.
• Device performance and hysteresis are sensitive to carrier type, which can be modulated by environmental factors like air adsorbates.