Dry Transfer of van der Waals Crystals to Noble Metal Surfaces To Enable Characterization of Buried Interfaces
| Autor: | Deep Jariwala, Thomas Darlington, Connor S. Bailey, Eric Pop, P. James Schuck, Kiyoung Jo, Andrey Krayev, Shuo Wang, Silvija Gradečak, Gang-yu Liu, Akshay Singh |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Materials science
Near and far field Nanotechnology 02 engineering and technology engineering.material 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Characterization (materials science) symbols.namesake symbols engineering General Materials Science Dry transfer Noble metal van der Waals force 0210 nano-technology Raman spectroscopy |
| Zdroj: | ACS Applied Materials & Interfaces. 11:38218-38225 |
| ISSN: | 1944-8252 1944-8244 |
| DOI: | 10.1021/acsami.9b09798 |
| Popis: | Two-dimensional (2D) transition-metal dichalcogenides (TMDCs) have been explored for many optoelectronic applications. Most of these applications require them to be on insulating substrates. However, for many fundamental property characterizations, such as mapping surface potential or conductance, insulating substrates are nonideal as they lead to charging and doping effects or impose the inhomogeneity of their charge environment on the atomically thin 2D layers. Here, we report a simple method of residue-free dry transfer of 2D TMDC crystal layers. This method is enabled via noble-metal (gold, silver) thin films and allows comprehensive nanoscale characterization of transferred TMDC crystals with multiple scanning probe microscopy techniques. In particular, intimate contact with underlying metal allows efficient tip-enhanced Raman scattering characterization, providing high spatial resolution (20 nm) for Raman spectroscopy. Further, scanning Kelvin probe force microscopy allows high-resolution mapping of surface potential on transferred crystals, revealing their spatially varying structural and electronic properties. The layer-dependent contact potential difference is clearly observed and explained by charge transfer from contacts with Au and Ag. The demonstrated sample preparation technique can be generalized to probe many different 2D material surfaces and has broad implications in understanding of the metal contacts and buried interfaces in 2D material-based devices. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|