title: Tuning the electronic properties of Ti-MoS2 contacts through introducing vacancies in monolayer MoS2.
abstract: The effect of vacancies in monolayer MoS2 on the electronic properties of a Ti-MoS2 top contact has been investigated using first-principles calculations. A Mo-vacancy is easier to form than a S-vacancy in a Ti-MoS2 top contact, especially under oxidation conditions. A Mo-vacancy eliminates the Schottky barrier of the Ti-MoS2 top contact, and a S-vacancy reduces the Schottky barrier from 0.28 to 0.15 eV. Mo-vacancies are beneficial for obtaining a high quality p-type Ti-MoS2 top contact, whereas S-vacancies are favorable to achieve a high quality n-type Ti-MoS2 top contact. Moreover, defective Ti-MoS2 top contacts have stronger dipole layers, a higher potential step and more transferred charges than a perfect ones. The electronic properties of Ti-MoS2 top contacts can be tuned by intrinsic vacancies in monolayer MoS2. Our findings provide important insights into the future design and fabrication of novel nanoelectronic devices with monolayer MoS2.
authors: State Key Lab of Solidification Processing, College of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, People's Republic of China. lpfeng@nwpu.edu.cn.
authors: Li-ping
authors: LP
authors: Feng
authors: Jie
authors: J
authors: Su
authors: Da-peng
authors: DP
authors: Li
authors: Zheng-tang
authors: ZT
authors: Liu