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arXiv · 1511.07619

Charge Trap Memory Based on Few-Layered Black Phosphorus

Qi Feng·Faguang Yan·Wengang Luo·Kaiyou Wang?
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Abstract

Atomically thin layered two-dimensional materials, including transition-metal dichacolgenide (TMDC) and black phosphorus (BP), (1) have been receiving much attention, because of their promising physical properties and potential applications in flexible and transparent electronic devices . Here, for the first time we show non-volatile chargetrap memory devices, based on field-effect transistors with large hysteresis, consisting of a few-layer black phosphorus channel and a three dimensional (3D) Al2O3 /HfO2 /Al2O3 charge-trap gate stack. An unprecedented memory window exceeding 12 V is observed, due to the extraordinary trapping ability of HfO2. The device shows a high endurance and a stable retention of ?25% charge loss after 10 years, even drastically lower than reported MoS2 flash memory. The high program/erase current ratio, large memory window, stable retention and high on/off current ratio, provide a promising route towards the flexible and transparent memory devices utilising atomically thin two-dimensional materials. The combination of 2D materials with traditional high-k charge-trap gate stacks opens up an exciting field of nonvolatile memory devices.

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Qi Feng, Faguang Yan, Wengang Luo, Kaiyou Wang?. 2015-11-24. Charge Trap Memory Based on Few-Layered Black Phosphorus. https://doi.org/10.1039/c5nr08065g

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