Ambipolar device simulation based on the drift-diffusion model in ion-gated transition metal dichalcogenide transistors
Ambipolar device simulation based on the drift-diffusion model in ion-gated transition metal dichalcogenide transistors
复制标题
基于离子门控过渡金属二硫化物晶体管漂移扩散模型的双极器件模拟
DOI：
10.1038/s41524-020-0314-9
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发表时间：
2020
影响因子：
9.7
通讯作者：
Y. Iwasa
中科院分区：
文献类型：
--
作者：
A. Ueda;Y. J. Zhang;N. Sano;H. Imamura;Y. Iwasa
离子门控被认为是研究从低压晶体管操作到栅极感应电子相位控制（包括超导性）的电子功能的有力工具。二维材料是典型的通道材料之一，具有多种栅极诱导现象。然而，这种离子门控晶体管器件的器件模拟从未被报道过，尽管它对未来器件结构的设计很重要。在本文中，我们在附着离子液体的二维材料wse2单层上建立了漂移-扩散（DD）模型，并成功地模拟了晶体管结构中的输运性质、电位分布、载流子密度分布。特别是，模拟解释了与带隙能量相当的栅极电压的双极性行为，以及在几篇实验论文中报道的沟道中p-n结的形成。这种奇特的行为是由于离子门控使肖特基势垒处的势谱发生了巨大变化而成为可能的。目前的结果表明，结合泊松方程的DD模型是一个很好的解释和预测离子门控晶体管进一步功能的平台，包括自旋、谷和光学自由度。
Ionic gating is known as a powerful tool for investigation of electronic functionalities stemming from low voltage transistor operation to gate-induced electronic phase control including superconductivity. Two-dimensional (2D) material is one of the archetypal channel materials which exhibit a variety of gate-induced phenomena. Nevertheless, the device simulations on such ion-gated transistor devices have never been reported, despite its importance for the future design of device structures. In this paper, we developed a drift-diffusion (DD) model on a 2D material, WSe2monolayer, attached with an ionic liquid, and succeeded in simulating the transport properties, potential profile, carrier density distributions in the transistor configuration. In particular, the simulation explains the ambipolar behavior with the gate voltage comparable to the band gap energy, as well as the formation of p-n junctions in the channel reported in several experimental papers. Such peculiar behavior becomes possible by the dramatic change of the potential profiles at the Schottky barrier by the ionic gating. The present result indicates that the DD model coupled to the Poisson equation is a fascinating platform to explain and predict further functionalities of ion-gated transistors through including the spin, valley, and optical degrees of freedom.