| AVS 63rd International Symposium & Exhibition | |
| 2D Materials Focus Topic | Monday Sessions |
| Session 2D+MI+SA-MoM |
| Session: | 2D Materials Characterization including Microscopy and Spectroscopy |
| Presenter: | Rudresh Ghosh, University of Texas at Austin |
| Authors: | R. Ghosh, University of Texas at Austin S.K. Banerjee, University of Texas at Austin D. Akinwande, University of Texas at Austin |
| Correspondent: | Click to Email |
Over the last decade, since the demonstration of exceptional physical, chemical and electrical properties of graphene, there has been a lot of interest in two-dimensional materials. Of these new materials significant effort has been focused on transition metal dichalcogenides (TMDs) due to their various possible applications. Initial work on TMDs, similar to that of graphene, has depended on exfoliated samples. In this work we present controlled large-area synthesis of highly crystalline few to monolayers of various TMDs (MoS2, WS2, WSe2) using both solid and gas precursors. Characterization of the TMDs are done using a combination of conventional techniques such as Raman and Photoluminescence spectroscopy, Atomic force microscopy, scanning and transmission electron microscopy. Shifts in Raman and PL spectra as a function of strain shows obvious differences between exfoliated and CVD grown material. New characterization tools with the capability of localized dielectric mapping (Microwave impedance microscopy) also show us a way to analyze defects that are inherent during CVD growth processes. Elemental identification of individual layers and their interfaces (using Time of Flight SIMS) are demonstrated as extremely useful for studying these 2d heterostructuress. Electrical device characterization and paths of optimization are also presented. Electrical characterization of the devices on various substrates is also presented.