State Key Laboratory of Surface Physics and Department of Physics, Fudan University , Shanghai 200433, China.
ACS Nano. 2015 Jan 27;9(1):612-9. doi: 10.1021/nn5059419. Epub 2014 Dec 17.
Charge-trap memory with high-κ dielectric materials is considered to be a promising candidate for next-generation memory devices. Ultrathin layered two-dimensional (2D) materials like graphene and MoS2 have been receiving much attention because of their fantastic physical properties and potential applications in electronic devices. Here, we report on a dual-gate charge-trap memory device composed of a few-layer MoS2 channel and a three-dimensional (3D) Al2O3/HfO2/Al2O3 charge-trap gate stack. Because of the extraordinary trapping ability of both electrons and holes in HfO2, the MoS2 memory device exhibits an unprecedented memory window exceeding 20 V. Importantly, with a back gate the window size can be effectively tuned from 15.6 to 21 V; the program/erase current ratio can reach up to 10(4), allowing for multibit information storage. Moreover, the device shows a high endurance of hundreds of cycles and a stable retention of ∼ 28% charge loss after 10 years, which is drastically lower than ever reported MoS2 flash memory. The combination of 2D materials with traditional high-κ charge-trap gate stacks opens up an exciting field of nonvolatile memory devices.
具有高介电常数材料的电荷俘获存储器被认为是下一代存储器件的有前途的候选者。由于其出色的物理性质和在电子器件中的潜在应用，像石墨烯和 MoS2 这样的超薄层二维 (2D) 材料受到了广泛关注。在这里，我们报告了一种由几层 MoS2 沟道和三维 (3D) Al2O3/HfO2/Al2O3 电荷俘获栅堆叠组成的双栅电荷俘获存储器器件。由于 HfO2 中电子和空穴的非凡俘获能力，MoS2 存储器器件表现出超过 20V 的前所未有的存储窗口。重要的是，通过背栅，可以有效地将窗口尺寸从 15.6V 调谐到 21V；编程/擦除电流比可高达 10(4)，允许进行多位信息存储。此外，该器件具有数百个循环的高耐久性，并且在 10 年后保留了约 28%的电荷损失，这大大低于以往报道的 MoS2 闪存。二维材料与传统的高介电常数电荷俘获栅堆叠的结合为非易失性存储器件开辟了一个令人兴奋的领域。
