| AVS 65th International Symposium & Exhibition | |
| 2D Materials Focus Topic | Wednesday Sessions |
| Session 2D+AM+EM+NS-WeM |
| Session: | Dopants, Defects, and Interfaces in 2D Materials |
| Presenter: | Yanfu Lu, The Pennsylvania State University |
| Authors: | Y. Lu, The Pennsylvania State University F. Zhang, The Pennsylvania State University S. Sinnott, The Pennsylvania State University M. Terrones, The Pennsylvania State University |
| Correspondent: | Click to Email |
Doping of 2D transition metal dichalcogenides has been discovered to be an effective way to tune the electronic structure and modify the lattice structure at the surface. The n-type and p-type doping of monolayer MoS2/WS2 heterostructures may enable the fabrication of field-effect transistors of ultra-low thickness. Plasma enhanced chemical vapor deposition provides a stable and controllable approach for introducing carbon dopants to monolayer WS2. Photoluminescence measurement indicates that the band gap of C-doped WS2 decreases by 0.17 eV. Corresponding first principles calculations provide the correlation between the position and chemical saturation of the carbon dopants and the electronic structure of the system. To verify covalently bonded dopants, we use Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning transmission electron microscopy to examine the pristine sample and carbon-doped samples. Subsequent I-V characteristics measurements prove p-type doping and the energy band diagram. Finally, the mechanism associated with and, more importantly, the structure-property relationship of chalcogen doping are analyzed. The resulting new insights of transition metal dichalcogenide-based heterostructures and alloys are discussed.