A Computational Study of Monolayer 2H WTe2 - Metal Interfaces
A Computational Study of Monolayer 2H WTe2 - Metal Interfaces
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单层 2H WTe2 - 金属界面的计算研究
DOI：
10.1002/pssb.201600837
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Jing Lu
中科院分区：
文献类型：
--
作者：
Chol So;Han Zhang;Yangyang Wang;Meng Ye;Yuanyuan Pan;Jing Lu
单层（ML）六方（2 H）WTe 2被预测为ML过渡金属二硫族化物中隧道场效应晶体管（TFET）和金属氧化物半导体场效应晶体管（MOSFET）的最佳沟道材料。基于2 H WTe 2的实际器件通常与金属接触。首次用从头算电子结构计算和量子输运模拟方法研究了ML 2 H WTe 2与Sc，Ti，Pd，Pt，Ag和Au的界面性质.由于ML 2 H WTe 2与金属基底的强粘附性，ML 2 H WTe 2在Sc，Ti，Pd，Pt基底上的能带被强烈破坏，ML 2 H WTe 2-Sc，-Ti，-Pd，-Pt体系被认为是新的金属材料。ML 2 H WTe 2与Ag和Au表面之间形成弱粘附，ML 2 H WTe 2的电子能带可识别。Ag和Au在垂直方向上与ML 2 H WTe 2形成n-型肖特基接触，电子肖特基势垒高度（SBH）分别为0.24和0.49 eV。相比之下，Pd、Pt和Ti在横向方向上与ML 2 H WTe 2形成p-型肖特基接触，空穴SBH分别为0.26、0.40和0.63 eV。我们的研究不仅提供了一个理论上的洞察ML 2 H WTe 2-金属界面，但也有助于ML 2 H WTe 2为基础的器件设计。
Monolayer (ML) hexagonal (2H) WTe2is predicted to be the best channel material of tunnel field effect transistor (TFET) and metal–oxide–semiconductor field effect transistor (MOSFET) among ML transition‐metal dichalcogenides. Actual devices based on 2H WTe2typically have a contact with metal. We explore for the first time the interfacial properties between ML 2H WTe2and Sc, Ti, Pd, Pt, Ag, and Au by usingab initioelectronic structure calculation andab initioquantum transport simulations. The energy bands of ML 2H WTe2on Sc, Ti, Pd, and Pt substrates are destroyed strongly due to strong adhesion of ML 2H WTe2with metal substrates, and ML 2H WTe2–Sc, −Ti, −Pd, and −Pt systems are regarded as new metallic materials. Weak adhesion is formed between ML 2H WTe2and the Ag and Au surfaces, with the electronic energy band of ML 2H WTe2being identifiable. Ag and Au formn‐type Schottky contact with ML 2H WTe2at the vertical direction with electron Schottky barrier height (SBH) of 0.24 and 0.49 eV, respectively. In contrast, Pd, Pt, and Ti formp‐type Schottky contact with ML 2H WTe2in the lateral direction with hole SBH of 0.26, 0.40, and 0.63 eV, respectively. Our study not only presents a theoretical insight into the ML 2H WTe2–metal interfaces but also help in ML 2H WTe2based device design.