Chemical vapor deposition growth of monolayer Er-doped molybdenum disulfide for efficient optoelectronic injection

Abstract The doping strategy of two-dimensional (2D) transition metal dichalcogenides has been widely used to modify intrinsic properties to satisfy potential applications in electronics, photonics and magnetics. Rare-earth elements with abundant optical properties are ideal dopants to endow 2D materials with improved optoelectronic properties. However, the large atomic size of rare-earth elements makes it difficult to substitute them into 2D lattices. Here we report the chemical vapor deposition growth of erbium (Er) substitutional doped monolayer molybdenum disulfide (MoS 2 ) with a doping concentration of 0.3%. An analysis of photoluminescent mapping was developed to evaluate the variance of uniformity of Er doping in MoS 2 to be 0.003 eV. The density functional theory calculation demonstrates the existence of impurity state in band gap caused by Er doping. The modification of electronic structure accelerates the opto-electron injection efficiency and improves the optoelectronic performance of the Er-MoS 2 field effect transistor. This work develops an easy approach to estimate the degree of doping uniformity of monolayer 2D materials and demonstrates their applications in optoelectronics.