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DOE OSTI · 22395724

Electrostatically transparent graphene quantum-dot trap layers for efficient nonvolatile memory

Kim, Young Rae·Jo, Yong Eun·Sung, Yeo Hyun·Won, Ui Yeon·Shin, Yong Seon·Kang, Won Tae
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Abstract

In this study, we have demonstrated nonvolatile memory devices using graphene quantum-dots (GQDs) trap layers with indium zinc oxide (IZO) semiconductor channel. The Fermi-level of GQD was effectively modulated by tunneling electrons near the Dirac point because of limited density of states and weak electrostatic screening in monolayer graphene. As a result, large gate modulation was driven in IZO channel to achieve a subthreshold swing of 5.21 V/dec (300 nm SiO{sub 2} gate insulator), while Au quantum-dots memory shows 15.52 V/dec because of strong electrostatic screening in metal quantum-dots. Together, discrete charge traps of GQDs enable stable performance in the endurance test beyond 800 cycles of programming and erasing. Our study suggests the exciting potential of GQD trap layers to be used for a highly promising material in non-volatile memory devices.

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77 NANOSCIENCE AND NANOTECHNOLOGYDENSITY OF STATESELECTRONSFERMI LEVELGRAPHENEINDIUM COMPOUNDSLAYERSMEMORY DEVICESMODULATIONQUANTUM DOTSSEMICONDUCTOR MATERIALSSILICON OXIDESTRAPSTUNNEL EFFECTZINC OXIDES

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Kim, Young Rae, Jo, Yong Eun, Sung, Yeo Hyun, Won, Ui Yeon, Shin, Yong Seon, Kang, Won Tae. 2015-03-09. Electrostatically transparent graphene quantum-dot trap layers for efficient nonvolatile memory. https://doi.org/10.1063/1.4914306

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