Strain-dependent doping behavior of WSe₂ monolayer: A first-principle calculation

Abstract

Control and enhancement of doping concentration in two-dimensional (2D) semiconductors is a critical issue. Here, we investigate the strain-dependent behavior of dopant formation energy (Eform) for transition metal-doped-WSe2 monolayer using Density functional theory (DFT) calculations. We found the Eform tends to reduce under tensile and compressive strain for the rhenium (Re), and vanadium (V) dopants, where the change in volume (ΔV) due to substitution is negligible. However, the Eform is energetically more favorable under tensile strain for niobium (Nb) and tantalum (Ta) dopants, where the ΔV is significantly larger. This suggests strain engineering can be used to enhance the doping concentration in 2D semiconductors.