Two-Terminal Nonvolatile Memories Based on Single-Walled Carbon Nanotubes

Reproducible current hysteresis is observed in semiconducting single-walled carbon nanotubes (SWCNTs) measured in a two-terminal configuration without a gate electrode. On the basis of this hysteresis, a two-terminal nonvolatile memory is realized by applying voltage pulses of opposite polarities across the SWCNT. Charge trapping at the SWCNT/SiO(2) interface is proposed to account for the observed phenomena; this explanation is supported by the direct correlation between the switching behaviors and SWCNT carrier types. In particular, a change in dominant carrier type induced by adsorbates in air leads to the direct transition of hysteresis evolution in the same device, providing further evidence for the proposed mechanism.