A computational study of monolayer hexagonal WTe2 to metal interfaces

Monolayer (ML) hexagonal (2H) WTe 2 is 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 WTe 2 typically have a contact with metal. We explore for the first time the interfacial properties between ML 2H WTe 2 and Sc, Ti, Pd, Pt, Ag, and Au by using ab initio electronic structure calculation and ab initio quantum transport simulations. The energy bands of ML 2H WTe 2 on Sc, Ti, Pd, and Pt substrates are destroyed strongly due to strong adhesion of ML 2H WTe 2 with metal substrates, and ML 2H WTe 2 –Sc, −Ti, −Pd, and −Pt systems are regarded as new metallic materials. Weak adhesion is formed between ML 2H WTe 2 and the Ag and Au surfaces, with the electronic energy band of ML 2H WTe 2 being identifiable. Ag and Au form n‐ type Schottky contact with ML 2H WTe 2 at the vertical direction with electron Schottky barrier height (SBH) of 0.24 and 0.49 eV, respectively. In contrast, Pd, Pt, and Ti form p‐ type Schottky contact with ML 2H WTe 2 in 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 WTe 2 –metal interfaces but also help in ML 2H WTe 2 based device design.