Ohmic contacts between monolayer WSe2 and two-dimensional titanium carbides
Ohmic contacts between monolayer WSe2 and two-dimensional titanium carbides
复制标题
单层WSe2和二维碳化钛之间的欧姆接触
DOI：
10.1016/j.carbon.2018.04.043
复制
发表时间：
2018-08-01
期刊：
影响因子：
10.9
通讯作者：
Lu, Jing
中科院分区：
文献类型：
--
作者：
Li, Qiuhui;Yang, Jie;Lu, Jing
欧姆接触的形成对于在基于二维 (2D) 材料的晶体管中实现高器件性能至关重要。通过从头算电子结构计算和量子输运模拟，我们揭示了二维碳化钛作为单层（ML）WSe2器件电极材料的巨大潜力。在垂直方向上，ML WSe2/Ti2C 和 ML WSe2/Ti2CY2（Y = F 和 OH）这三种混合异质结构中均不存在隧道势垒和肖特基势垒，这意味着垂直载流子注入效率较高。在横向上，虽然原始Ti2C和ML WSe2形成电子势垒为0.40 eV的肖特基接触，但Ti2CF2/ML WSe2和Ti2C(OH)(2)/ML WSe2分别形成p型准欧姆接触和n型欧姆接触。因此，通过适当控制表面官能团，二维碳化钛可以成为ML WSe2晶体管电极材料的有希望的候选者。 (C) 2018 Elsevier Ltd. 保留所有权利。
Formation of Ohmic contact is crucial for achieving high device performance in two-dimensional (2D) materials based transistors. By using ab initio electronic structure calculations and quantum transport simulations, we reveal the great potential of 2D titanium carbides as the electrode materials for monolayer (ML) WSe2 device. In the vertical direction, both tunnel barrier and Schottky barrier are absent in all the three hybrid heterostructures of ML WSe2/Ti2C and ML WSe2/Ti2CY2 (Y = F and OH), implying a high vertical carrier injection efficiency. In the lateral direction, although pristine Ti2C and ML WSe2 form a Schottky contact with electron barrier of 0.40 eV, Ti2CF2/ML WSe2 and Ti2C(OH)(2)/ML WSe2 form p-type quasi-Ohmic and n-type Ohmic contacts, respectively. Therefore, 2D titanium carbides can be promising candidates as electrode materials for the ML WSe2 transistors by proper controlling of the surface functional group. (C) 2018 Elsevier Ltd. All rights reserved.