Tunable electronic properties and Schottky barrier in graphene/WSe2 heterostructure under out-of-plane strain and electric field

Tuning the electrical transport behavior and reducing the Schottky barrier height of nanoelectronic devices remain a great challenge. To solve this issue, the electronic properties and Schottky barrier of the graphene/WSe2 heterostructure are investigated by the first-principles method under out-of-plane strain and electric field. Our results show that the WSe2 monolayer and graphene could form a stable van der Walls heterostructure and the intrinsic electronic properties are well preserved. Further, a transformation of Schottky contact from n-type to p-type occurs at d = 3.87 A and E = +0.06 V/A. In addition, an Ohmic contact is formed with E = -0.50, ±0.60 V/A. Lastly, the effective masses of electron and hole are calculated to be 0.057 m0 and -0.055 m0 at the equilibrium state, respectively, indicating that the heterostructure has a high carrier mobility. Our research will provide promising approaches for future design and development the graphene/WSe2 nano-field effect transistors.